DIGITAL CAMERA

Digital Camera Patent Abstract
A digital camera of the present invention includes a receiving portion 155 that receives a control signal from a remote controller, and a microcomputer 110 having a live view mode controlling so that image data generated by a CMOS sensor 130 or image data obtained by subjecting the image data generated by the CMOS sensor 130 to predetermined processing is displayed on a liquid crystal monitor 150 as a moving image in real time, wherein when the receiving portion 155 receives the control signal from the remote controller, the microcomputer 110 controls so as to shift the digital camera to a live view mode. Due to this configuration, in a digital camera that includes a movable mirror and is capable of displaying a subject image in a live view through an electronic viewfinder, the operability thereof can be enhanced.

Digital Camera Patent Claims
1. A digital camera having a movable mirror provided so as to enter or retract with respect to an optical path of an image pickup optical system for purpose of guiding a subject image to an optical viewfinder, comprising: an image pickup element that captures the subject image formed by the image pickup optical system to generate image data; a display portion that displays the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing; a receiving portion that receives a control signal from a remote controller; and a control portion having a live view mode controlling so that the image data generated by the image pickup element or the image data obtained by subjecting the image data generated by the image pickup element to predetermined processing is displayed on the display portion as a moving image in real time, wherein when the receiving portion receives the control signal from the remote controller, the control portion controls so as to shift the digital camera to a live view mode.

2. A digital camera having a movable mirror provided so as to enter or retract with respect to an optical path of an image pickup optical system for purpose of guiding a subject image to an optical viewfinder, comprising: an image pickup element that captures the subject image formed by the image pickup optical system to generate image data; a display portion that displays the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing; a tripod fixing portion for fixing the digital camera to a tripod; and a control portion having a live view mode controlling so that the image data generated by the image pickup element or the image data obtained by subjecting the image data generated by the image pickup element to predetermined processing is displayed on the display portion as a moving image in real time, wherein when the digital camera is fixed to the tripod by the tripod fixing portion, the control portion controls so as to shift the digital camera to a live view mode.

3. The digital camera according to claim 2, further comprising: a distance-measuring portion that receives the subject image and obtains information on a distance from the subject to the digital camera in a state where the movable mirror enters the optical path; and an autofocus portion that adjusts a focus of the subject image by adjusting the image pickup optical system in accordance with measurement results of the distance-measuring portion, wherein when the digital camera is fixed to the tripod by the tripod fixing portion, the control portion controls the autofocus portion first so that an autofocus operation is performed immediately after the digital camera is fixed to the tripod or after a predetermined time elapses from the time when the digital camera is fixed to the tripod, and thereafter, the control portion controls so that the digital camera is shifted to the live view mode.

4. The digital camera according to claim 3, further comprising a setting portion that sets the control portion in the live view mode, wherein when the digital camera is fixed to the tripod by the tripod fixing portion, the control portion controls so as to shift the digital camera to the live view mode after controlling the autofocus portion first so that the autofocus operation is performed, in accordance with setting of the live view mode by the setting portion.

5. The digital camera according to claim 2, further comprising an autofocus portion that adjusts a focus of the subject image by adjusting the image pickup optical system, using contrast of the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing, wherein when the digital camera is fixed to the tripod by the tripod fixing portion, the control portion controls the autofocus portion so that the autofocus operation is operated immediately after the digital camera is fixed to the tripod by the tripod fixing portion or after a predetermined time elapses from the time when the digital camera is fixed to the tripod.

6. The digital camera according to claim 5, further comprising a setting portion that sets the control portion in the live view mode, wherein when the digital camera is fixed to the tripod by the tripod fixing portion, the control portion controls so as to shift the digital camera to the live view mode and controls the autofocus portion so that the autofocus operation is performed, in accordance with setting of the live view mode by the setting portion.

7. A digital camera having a movable mirror provided so as to enter or retract with respect to an optical path of an image pickup optical system for purpose of guiding a subject image to an optical viewfinder, comprising: an image pickup element that captures the subject image formed by the image pickup optical system to generate image data; a display portion that displays the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing; a shaking detecting portion that detects shaking of the digital camera; and a control portion having a live view mode controlling so that the image data generated by the image pickup element or the image data obtained by subjecting the image data generated by the image pickup element to predetermined processing is displayed on the display portion as a moving image in real time, wherein the control portion controls so as to shift the digital camera to a live view mode in accordance with detection results of the shaking detecting portion.

8. The digital camera according to claim 7, further comprising: a distance-measuring portion that receives the subject image and obtains information on a distance from the subject to the digital camera in a state where the movable mirror enters the optical path; and an autofocus portion that adjusts a focus of the subject image by adjusting the image pickup optical system in accordance with measurement results of the distance-measuring portion, wherein the control portion controls so as to shift the digital camera to the live view mode after controlling the autofocus portion first so that an autofocus operation is performed, in accordance with the detection results of the shaking detecting portion.

9. The digital camera according to claim 8, further comprising a setting portion that sets the control portion in the live view mode, wherein the control portion controls so as to shift the digital camera to the live view mode after controlling the autofocus portion first so that the autofocus operation is performed, in accordance with the detection results of the shaking detecting portion and setting of the live view mode by the setting portion.

10. The digital camera according to claim 7, further comprising an autofocus portion that adjusts a focus of the subject image by adjusting the image pickup optical system, using contrast of the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing, wherein the control portion controls the autofocus portion so that an autofocus operation is performed in accordance with the detection results of the shaking detecting portion.

11. The digital camera according to claim 10, further comprising a setting portion that sets the control portion in the live view mode, wherein the control portion controls so as to shift the digital camera to the live view mode and controls the autofocus portion so that the autofocus operation is performed, in accordance with the detection results of the shaking detecting portion and setting of the live view mode by the setting portion.

Digital Camera Patent Description
BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a digital camera. In particular, the present invention relates to a digital camera having a movable mirror, which enables a subject image to be observed through an electronic viewfinder.

[0003] 2. Description of Related Art

[0004] A digital single-lens reflex camera has an electronic viewfinder and an optical viewfinder, so that a subject image formed by an image pickup optical system is switched with a movable mirror, and can be observed through the optical viewfinder. Because of this, displacement does not occur between a subject image in a recording image and a subject image displayed with the optical viewfinder, whereby an image pickup manipulation can be performed satisfactorily.

[0005] However, the digital single-lens reflex camera needs to switch the movable mirror in accordance with an operation state. This requires a user's manual manipulation, and a time therefor needs to be kept. Particularly, in a camera with a "live view mode" in which an image generated by an image pickup element is displayed on a display portion in real time, the movable mirror needs to be switched frequently in accordance with an autofocus operation, a diaphragm adjustment operation, and an image pickup operation.

[0006] A digital single-lens reflex camera with a live view mode is disclosed by, for example, Patent Document 1 (JP 2001-272593 A).

[0007] However, in the digital single-lens reflex camera disclosed by Patent Document 1, the operability involved in switching of the movable mirror is not improved sufficiently. Therefore, even if the live view mode is set to be executable, it is difficult for a user to use it, and consequently, the user captures an image while observing it with the optical viewfinder.

SUMMARY OF THE INVENTION

[0008] The object of the present invention is to provide a digital camera with operability thereof enhanced, which includes a movable mirror and is capable of displaying a subject image in a live view through an electronic viewfinder.

[0009] A first digital camera according to the present invention having a movable mirror provided so as to enter or retract with respect to an optical path of an image pickup optical system for purpose of guiding a subject image to an optical viewfinder includes: an image pickup element that captures the subject image formed by the image pickup optical system to generate image data; a display portion that displays the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing; a receiving portion that receives a control signal from a remote controller; and a control portion having a live view mode controlling so that the image data generated by the image pickup element or the image data obtained by subjecting the image data generated by the image pickup element to predetermined processing is displayed on the display portion as a moving image in real time, wherein when the receiving portion receives the control signal from the remote controller, the control portion controls so as to shift the digital camera to a live view mode.

[0010] According to the above configuration, when a signal giving an instruction regarding the autofocus operation, an image pickup start signal, a self-timer setting signal, or the like is received from the remote controller, the digital camera is shifted to the live view mode automatically. When an image is captured with the remote controller, the image is captured under the condition that the digital camera is away from the hand (e.g., under the condition that the digital camera is fixed to a tripod, the digital camera is left on a desk, etc.) in many cases. In such a case, an image is likely to be grasped if the image is captured with an electronic viewfinder having a large screen, compared with the case where the image is captured with the optical viewfinder. In the case of receiving a signal from the remote controller, the digital camera is shifted to the live view mode automatically as described above, whereby the time and labor for switching to the live view mode manually are saved, which enhances the operability.

[0011] Furthermore, a second digital camera according to the present invention having a movable mirror provided so as to enter or retract with respect to an optical path of an image pickup optical system for purpose of guiding a subject image to an optical viewfinder includes: an image pickup element that captures the subject image formed by the image pickup optical system to generate image data; a display portion that displays the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing; a tripod fixing portion for fixing the digital camera to a tripod; and a control portion having a live view mode controlling so that the image data generated by the image pickup element or the image data obtained by subjecting the image data generated by the image pickup element to predetermined processing is displayed on the display portion as a moving image in real time, wherein when the digital camera is fixed to the tripod by the tripod fixing portion, the control portion controls so as to shift the digital camera to a live view mode.

[0012] According to the above configuration, when the digital camera is fixed to the tripod, the digital camera is shifted to the live view mode automatically. When an image is captured under the condition that the digital camera is fixed to the tripod, an image is likely to be grasped if the image is captured with an electronic viewfinder having a large screen, compared with the case where the image is captured with the optical viewfinder. When the digital camera is fixed to the tripod, the digital camera is shifted to the live view mode automatically as described above, whereby the time and labor for switching to the live view mode manually are saved, which enhances the operability.

[0013] Furthermore, a third digital camera according to the present invention having a movable mirror provided so as to enter or retract with respect to an optical path of an image pickup optical system for purpose of guiding a subject image to an optical viewfinder includes: an image pickup element that captures the subject image formed by the image pickup optical system to generate image data; a display portion that displays the image data generated by the image pickup element or image data obtained by subjecting the image data generated by the image pickup element to predetermined processing; a shaking detecting portion that detects shaking of the digital camera; and a control portion having a live view mode controlling so that the image data generated by the image pickup element or the image data obtained by subjecting the image data generated by the image pickup element to predetermined processing is displayed on the display portion as a moving image in real time, wherein the control portion controls so as to shift the digital camera to a live view mode in accordance with detection results of the shaking detecting portion.

[0014] According to the above configuration, the digital camera is shifted to the live view mode in accordance with the detection results of the shaking detecting portion, whereby the time and labor for switching to the live view mode manually are saved, which enhances the operability.

[0015] According to the present invention, in a digital camera that includes a movable mirror and is capable of displaying a subject image in a live view through an electronic viewfinder, the operability thereof can be enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a schematic view illustrating an outline of a camera according to Embodiments 1-5.

[0017] FIG. 2 is a block diagram showing a configuration of a camera body according to Embodiments 1-5.

[0018] FIG. 3 is a back view of the camera body according to Embodiments 1-5.

[0019] FIG. 4 is a block diagram showing a configuration of an interchangeable lens according to Embodiments 1-5.

[0020] FIG. 5 is a schematic view when the inside of a mirror box of the camera according to Embodiments 1-5 is in a state B.

[0021] FIG. 6 is a schematic view when the inside of the mirror box of the camera according to Embodiments 1-5 is in a state C.

[0022] FIG. 7 is a flowchart illustrating an operation when an AV button is pressed in an OVF mode.

[0023] FIG. 8 is a flowchart illustrating an operation when a diaphragm stop-down button is pressed in a live view mode.

[0024] FIG. 9 is a flowchart illustrating an operation when a live view preview button is pressed in the live view mode.

[0025] FIG. 10 is a schematic view showing an example when a part is displayed in an enlarged state on a liquid crystal monitor.

[0026] FIG. 11 is a flowchart illustrating an operation when an image is captured using an optical viewfinder in a manual focus mode.

[0027] FIG. 12 is a schematic view showing a configuration of an image file storing an image for recording.

[0028] FIG. 13 is a flowchart illustrating an operation when an image is captured using a liquid crystal monitor 150 in the manual focus mode.

[0029] FIG. 14 is a flowchart illustrating an operation when an image is captured using an optical viewfinder in a single focus mode.

[0030] FIG. 15 is a flowchart illustrating an operation when an image is captured using the liquid crystal monitor 150 in the single focus mode.

[0031] FIG. 16 is a flowchart illustrating an operation when an image is captured using an optical viewfinder in a continuous focus mode.

[0032] FIG. 17 is a flowchart illustrating an operation when an image is captured using the liquid crystal monitor in the continuous focus mode.

[0033] FIG. 18 is a flowchart illustrating an autofocus operation when an OVF mode is switched to the live view mode.

[0034] FIG. 19 is a schematic view showing a display screen displaying a focused point.

[0035] FIG. 20 is a schematic view showing the arrangement of line sensors included in an AF sensor.

[0036] FIG. 21 is a flowchart illustrating an operation when foreign matter such as dust adhering to a protective material is removed using an supersonic vibration generator.

[0037] FIG. 22 is a flowchart illustrating a stroboscopic image pickup operation in the case of using only the AE sensor.

[0038] FIG. 23 is a flowchart illustrating a stroboscopic image pickup operation in the case of using the AE sensor and a CMOS sensor.

[0039] FIG. 24 is a flowchart illustrating an operation when the live view mode is reset by shock.

[0040] FIG. 25 is a flowchart illustrating an operation when an LV preview button is pressed in the OVF mode.

[0041] FIG. 26 is a flowchart illustrating an operation at a time of shift to the live view mode due to a remote control manipulation.

[0042] FIG. 27 is a flowchart illustrating an operation when the camera is shifted to the live view mode by being fixed to a tripod.

[0043] FIG. 28 is a flowchart illustrating an operation when the camera is shifted to the live view mode by rotating the liquid crystal monitor.

[0044] FIG. 29 is a flowchart illustrating an operation when the camera is shifted to the live view mode by being connected to an external terminal.

[0045] FIG. 30 is a flowchart illustrating an operation when the camera is shifted to the live view mode by setting an aspect ratio.

[0046] FIG. 31 is a flowchart illustrating an operation when the camera is shifted to the live view mode by operating a diaphragm ring.

[0047] FIG. 32 is a flowchart illustrating an operation when the live view mode is cancelled by operating a menu button.

[0048] FIG. 33 is a flowchart illustrating an operation when the live view mode is cancelled by turning off a power supply.

[0049] FIG. 34 is a flowchart illustrating an operation when the live view mode is cancelled by opening a battery cover.

[0050] FIG. 35 is a flowchart illustrating an operation when the live view mode is cancelled due to the decrease in a supply voltage.

[0051] FIG. 36 is a flowchart illustrating an operation when the live view mode is cancelled due to the decrease in a supply voltage.

[0052] FIG. 37 is a flowchart illustrating an operation when the live view mode is cancelled by being connected to the external terminal.

[0053] FIG. 38 is a flowchart illustrating a shift operation to a single focus mode involved in the shift to the live view mode.

[0054] FIG. 39 is a flowchart illustrating a shift operation to an OVF mode involved in the shift to the continuous focus mode.

[0055] FIG. 40 is a schematic view showing a display screen when a plurality of real-time images are displayed on the liquid crystal monitor.

[0056] FIG. 41 is a flowchart illustrating a multi-display operation in a live view.

DETAILED DESCRIPTION OF THE INVENTION

[Contents]

[0057] 1. Embodiment 1 [0058] 1-1 Configuration of digital camera [0059] 1-1-1 Outline of entire configuration [0060] 1-1-2 Configuration of camera body [0061] 1-1-3 Configuration of interchangeable lens [0062] 1-1-4 State of mirror box [0063] 1-1-5 Correspondence between configuration of present embodiment and configuration of present invention [0064] 1-2 Operation of digital camera [0065] 1-2-1 Display operation of real-time image [0066] 1-2-1-1 Operation during use of optical viewfinder [0067] 1-2-1-2 Operation during use of liquid crystal monitor [0068] 1-2-2 Adjustment of diaphragm and display operation of real-time image [0069] 1-2-2-1 Operation during use of optical viewfinder [0070] 1-2-2-2 Operation during use of liquid crystal monitor [0071] 1-2-3 Image pickup operation of image for recording [0072] 1-2-3-1 Image pickup operation using manual focus [0073] 1-2-3-1-1 Operation during use of optical viewfinder [0074] 1-2-3-1-2 Operation during use of liquid crystal monitor [0075] 1-2-3-2 Image pickup operation using single focus [0076] 1-2-3-2-1 Operation during use of optical viewfinder [0077] 1-2-3-2-2 Operation during use of liquid crystal monitor [0078] 1-2-3-3 Image pickup operation using continuous focus [0079] 1-2-3-3-1 Operation during use of optical viewfinder [0080] 1-2-3-3-2 Operation during use of liquid crystal monitor [0081] 1-2-4 Autofocus operation during shift to live view mode [0082] 1-2-5 Display operation of distance-measuring point [0083] 1-2-6 Dust automatic removing operation [0084] 1-2-7 Stroboscopic image pickup operation in live view mode [0085] 1-2-7-1 Photometric operation using only AE sensor [0086] 1-2-7-2 Photometric operation using AE sensor and CMOS sensor [0087] 1-2-7-3 Photometric operation using only CMOS sensor [0088] 2. Embodiment 2 [0089] 2-1 Operation during shift to live view mode by diaphragm adjustment [0090] 2-2 Operation during shift to live view mode by remote control manipulation [0091] 2-3 Operation during shift to live view mode by fixing tripod [0092] 2-4 Operation during shift to live view mode by rotation of liquid crystal monitor [0093] 2-5 Operation during shift to live view mode by connection to external terminal [0094] 2-6 Operation during shift to live view mode by setting of aspect ratio other than 4:3 [0095] 2-7 Operation during shift to live view mode by operation of diaphragm ring [0096] 3. Embodiment 3 [0097] 3-1 Operation of canceling live view mode by menu button manipulation [0098] 3-2 Operation of canceling live view mode in accordance with power supply turn-off manipulation [0099] 3-3 Operation of canceling live view mode in accordance with opening of battery cover [0100] 3-4 Operation of canceling live view based on detection of low battery [0101] 3-5 Operation of canceling live view mode in accordance with removal of lens [0102] 3-6 Operation of canceling live view mode in accordance with connection to external terminal [0103] 4. Embodiment 4 [0104] 4-1 Operation of shifting from continuous focus mode to single focus mode [0105] 4-2 Operation of shifting from live view mode to OVF mode [0106] 5. Embodiment 5 Live view display of multi-screen [0107] 6. Embodiment 6 Other embodiments

Embodiment 1

[0107] (1-1 Configuration of Digital Camera).

[0108] [1-1-1 Outline of Entire Configuration]

[0109] FIG. 1 is a schematic view illustrating a configuration of a camera 10. The camera 10 is composed of a camera body 100 and an interchangeable lens 200 attachable/detachable with respect to the camera body 100.

[0110] The camera body 100 captures a subject image condensed by an optical system included in the interchangeable lens 200, and records it as image data. The camera body 100 includes a mirror box 120. The mirror box 120 switches an optical path of an optical signal from the optical system included in the interchangeable lens 200 so as to allow the subject image to be incident selectively upon either a CMOS sensor 130 (complementary metal-oxide semiconductor) or an eyepiece 136. The mirror box 120 includes movable mirrors 121a, 121b, a mirror driving portion 122, a shutter 123, a shutter driving portion 124, a focusing glass 125, and a prism 126.

[0111] The movable mirror 121a is placed so as to enter/retract with respect to the optical path of an image pickup optical system so as to guide the subject image to an optical viewfinder. The movable mirror 121b is placed so as to enter/retract with respect to the optical path of the image pickup optical system together with the movable mirror 121a. The movable mirror 121b reflects a part of the optical signal input from the optical system included in the interchangeable lens 200 to allows it to be incident upon an AF sensor 132 (AF: auto focus). The AF sensor 132 is, for example, a light-receiving sensor for autofocusing of a phase difference detection system. When the AF sensor 132 is of the phase difference detection system, the AF sensor 132 detects a defocus amount of the subject image.

[0112] When the movable mirror 121a is positioned in the optical path of the image pickup optical system, a part of the optical signal input from the optical system included in the interchangeable lens 200 is incident upon the eyepiece 136 via the focusing glass 125 and the prism 126. Furthermore, the optical signal reflected by the movable mirror 121a is diffused by the focusing glass 125. Then, a part of the diffused optical signal is incident upon an AE sensor 133 (AE: automatic exposure). On the other hand, when the movable mirrors 121a and 121b are not positioned in the optical path of the image pickup optical system, the optical signal input from the optical system included in the interchangeable lens 200 is incident upon the CMOS sensor 130.

[0113] The mirror driving portion 122 includes mechanical components such as a motor and a spring. Furthermore, the mirror driving portion 122 drives the movable mirrors 121a, 121b based on the control of a microcomputer 110.

[0114] The shutter 123 can switch between the interruption and the passage of the optical signal incident via the interchangeable lens 200. The shutter driving portion 124 includes mechanical components such as a motor and a spring. Furthermore, the shutter driving portion 124 drives the shutter 123 based on the control of the microcomputer 110. The mirror driving portion 122 and the shutter driving portion 124 may use separate motors or have one motor in common.

[0115] At the back of the camera body 100, a liquid crystal monitor 150 is placed. The liquid crystal monitor 150 is capable of displaying image data generated by the CMOS sensor 130 or image data obtained by subjecting the image data generated by the CMOS sensor 130 to predetermined processing.

[0116] The optical system in the interchangeable lens 200 includes an objective lens 220, a zoom lens 230, a diaphragm 240, an image fluctuation correcting unit 250, and a focus motor 260. A CPU 210 controls the optical system. The CPU 210 is capable of transmitting/receiving a control signal and information on the optical system with respect to the microcomputer 110 on the camera body 100 side.

[0117] In the specification, a function of displaying a subject image on the liquid crystal monitor 150 in real time and a display thereof will be referred to as a "live view" or "LV". Furthermore, a control mode of the microcomputer 110 for allowing a live view operation to be performed as such will be referred to as a "live view mode" or an "LV mode". Furthermore, a function in which an optical image incident via the interchangeable lens 200 can be recognized visually through the eyepiece 136 will be referred to as a "finder view" or an "OVF". Furthermore, a control mode of the microcomputer 110 for allowing the OVF function to be operated as such will be referred to as an "OVF mode".

[0118] [1-1-2 Configuration of Camera Body]

[0119] FIG. 2 shows a configuration of the camera body 110. As shown in FIG. 2, the camera body 110 has various sites, and the microcomputer 110 controls them. In the present embodiment, a description will be made in which one microcomputer 110 controls the entire camera body 100. However, even if the present embodiment is configured so that a plurality of control portions control the camera body 100, the camera body 100 is operated similarly.

[0120] A lens mount portion 135 is a member that attaches/detaches the interchangeable lens 200. The lens mount portion 125 can be electrically connected to the interchangeable lens 200 using a connection terminal or the like, and also can be mechanically connected thereto using a mechanical member such as an engagement member. The lens mount portion 135 can output a signal from the interchangeable lens 200 to the microcomputer 110, and can output a signal from the microcomputer 110 to the interchangeable lens 200. The lens mount portion 135 has a hollow configuration.

Therefore, the optical signal incident from the optical system included in the interchangeable lens 200 passes through the lens mount portion 135 to reach the mirror box 120.

[0121] The mirror box 120 guides the optical signal having passed through the lens mount portion 135 to the CMOS sensor 130, the eyepiece lens 136, the AF sensor 132, and the AE sensor 133 in accordance with the inside state. The switching of the optical signal by the mirror box will be described in "1-1-4 State of mirror box".

[0122] The CMOS sensor 130 electrically converts the optical signal incident through the mirror box 120 to generate image data. The generated image data is converted from an analog signal to a digital signal by an A/D converter 131 to be output to the microcomputer 110. The generated image data may be subjected to predetermined image processing while being output from the CMOS sensor 130 to the A/D converter 131 or while being output from the A/D converter 131 to the microcomputer 110.

[0123] The eyepiece lens 136 passes the optical signal incident through the mirror box 120. At this time, in the mirror box 120, as shown in FIG. 1, the optical signal incident from the interchangeable lens 200 is reflected by the movable mirror 121a to form a subject image on the focusing glass 125. Then, the prism 126 reflects the subject image to output it to the eyepiece 136. Consequently, a user visually can recognize the subject image from the mirror box 120. Herein, the eyepiece 136 may be composed of a single lens or a lens group including a plurality of lenses. Furthermore, the eyepiece 136 may be held on the camera body 100 in a fixed manner, or held thereon movably for the purpose of adjusting a visibility or the like. The optical viewfinder is composed of the focusing glass 125, the prism 126, and the eyepiece 136, and is configured in an optimum shape for displaying an image having a composition with an aspect ratio of 4:3. It should be noted that the optical viewfinder may be configured in an optimum shape for displaying an image having a composition with another aspect ratio. For example, the optical viewfinder may have an optimum shape for displaying an image having a composition with an aspect ratio of 16:9, or an optimum shape for displaying an image having a composition with an aspect ratio of 3:2.

[0124] A protective material 138 protects the surface of the CMOS sensor 130. By placing the protective material 138 on the front surface of the CMOS sensor 130, foreign matter such as dust can be prevented from adhering to the surface of the CMOS sensor 130. The protective material 138 can be formed of a transparent material such as glass or plastic.

[0125] An supersonic vibration generator 134 is activated in accordance with a signal from the microcomputer 110 to generate an supersonic vibration. The supersonic vibration generated in the supersonic vibration generator 134 is transmitted to the protective material 138. Because of this, the protective material 138 can vibrate to shake off foreign matter such as dust adhering to the protective material 138. The supersonic vibration generator 134 can be realized, for example, by attaching a piezoelectric element to the protective material 138. In this case, the piezoelectric element can be vibrated by supplying an AC current to the piezoelectric element attached to the protective material 138.

[0126] A strobe 137 flashes in accordance with an instruction of the microcomputer 110. The strobe 137 may be contained in the camera body 100, or may be of a type attachable/detachable with respect to the camera body 100. In the case of an attachable/detachable strobe, it is necessary to provide a strobe attachment portion such as a hot shoe on the camera body 100.

[0127] A release button 141 receives an instruction from the user regarding the activation of an autofocus operation and a photometric operation, and also receives an instruction from the user regarding the start of capturing an image for recording by the CMOS sensor 130. The release button 141 can receive halfway depression and full depression. When the release button 141 is pressed halfway by the user in an autofocus mode, the microcomputer 110 instructs the interchangeable lens 200 to perform the autofocus operation based on a signal from the AF sensor 132. Furthermore, when the release button 141 is pressed halfway by the user in an automatic exposure mode, the microcomputer 110 instructs the interchangeable lens 200 to perform the photometric operation based on a signal from the AE sensor 133. On the other hand, when the release button 141 is pressed fully by the user, the microcomputer 110 controls the mirror box 120, the CMOS sensor 130, and the like to capture the image for recording. Then, the microcomputer 110 subjects the captured image for recording to YC conversion processing, resolution conversion processing, compression processing, or the like, if required, thereby generating image data for recording. The microcomputer 110 records the generated image data for recording on a memory card 300 via a card slot 153. The release button 141 can has a function of responding to the halfway depression and a function of responding to the full depression by allowing the release button 141 to contain two switches. In this case, one of the switches is switched to an ON state by the halfway depression, and the other switch is switched to an ON state by the full depression.

[0128] A manipulation portion 140 can receive various instructions from the user. An instruction received by the manipulation portion 140 is transmitted to the microcomputer 110. FIG. 3 is a back view of the camera body 100. As shown in FIG. 3, the back surface of the camera body 100 includes a menu button 140a, a cross key 140b, a set button 140c, a rotation dial 140d, a viewfinder switch 140e, a focus mode switch 140f, a strobe activation button 140h, an LV preview button 140j, a stop-down button 140k, an AV button 140m, and a power supply switch 142. On the upper surface of the camera body 100, a hand shaking correction mode switch button 140g and the release button 141 are placed.

[0129] The menu button 140 allows the liquid crystal monitor 150 to display setting information on the camera body 10, thereby enabling the user to change the setting. The cross key 140b selects various settings, items, images, or the like displayed on the liquid crystal monitor 150, and for example, can move a cursor or the like. The set button 140c determines the selected various settings, items, images, or the like displayed on the liquid crystal monitor 150. The rotation dial 140d is an operation member that selects various settings, items, images, or the like displayed on the liquid crystal monitor 150 in the same way as in the cross key 140b, and can move a cursor or the like, for example, by rotating. The viewfinder switch 140e selects either guiding an optical image to the eyepiece 136 or displaying a captured electric image on the liquid crystal monitor 150. The focus mode switch 140f selects either setting a focus mode in a manual focus mode or setting the focus mode in an autofocus mode. The hand shaking correction mode switch 140g is capable of selecting whether hand shaking correction should be performed. Furthermore, the hand shaking correction mode switch 140g can select a control mode of hand shaking correction. The stop-down button 140k adjusts the diaphragm in the live view mode. The LV preview button 140j adjusts the diaphragm and displays a part of an image displayed on the liquid crystal monitor 150 in an enlarged state, in the live view mode. The AV button 140m adjusts the diaphragm in the OVF mode.

[0130] As shown in FIG. 2, the liquid crystal monitor 150 receives a signal from the microcomputer 110 and displays an image or information on various settings. The liquid crystal monitor 150 is capable of displaying image data generated by the CMOS sensor 130, or image data obtained by subjecting the image data generated in the CMOS sensor 130 to predetermined processing. The liquid crystal monitor 150 is capable of displaying the image data held in the memory card 300 after subjecting the image data to predetermined processing such as decompression processing in the microcomputer 110, if required. As shown in FIG. 3, the liquid crystal monitor 150 is placed on the back surface of the camera body 100. The liquid crystal monitor 150 is placed rotatably with respect to the camera body 100. A contact point 151 detects the rotation of the liquid crystal monitor 150. The liquid crystal monitor 150 has an optimum shape for displaying an image having a composition with an aspect ratio of 4:3. It should be noted that the liquid crystal monitor 150 is also capable of displaying an image having a composition with another aspect ratio (e.g., 3:2 or 16:9).

[0131] An external terminal 152 outputs image data and information on various settings to an external apparatus. The external terminal 152 is, for example, a USB terminal (USB: universal serial bus), a terminal for an interface pursuant to an IEEE 139 specification (IEEE: Institute of Electrical and Electronic Engineers), or the like. Furthermore, when a connection terminal from the external apparatus is connected to the external terminal 152, the microcomputer 110 is notified of the connection.

[0132] A power supply controller 146 controls the supply of power from a battery 400 contained in a battery box 143 to a member in a camera 10, such as the microcomputer 110. When the power supply switch 142 is switched on, the power supply controller 146 starts supplying the power from the battery 400 to the member in the camera 10. Furthermore, the power supply controller 146 includes a sleep function, and when the power supply switch 142 remains unoperated for a predetermined period of time keeping an ON state, the power supply switch 142 stops the supply of power (excluding partial members in the camera 10). Furthermore, the power supply controller 146 notifies the microcomputer 110 that the battery cover 144 is opened, based on a signal from the contact point 145 that monitors the opening/closing of the battery cover 144. The battery cover 144 is a member that opens/closes an opening of the battery box 143. In FIG. 2, the power supply controller 146 is configured so as to supply power to each member in the camera 10 through the microcomputer 110. However, even if the power supply controller 146 is configured so as to supply power directly from the power supply controller 146, the camera 10 is operated similarly.

[0133] A tripod fixing portion 147 is a member that fixes a tripod (not shown) to the camera body 100, and is composed of a screw or the like.

[0134] The contact point 148 monitors whether or not the tripod is fixed to the tripod fixing portion 147, and notifies the microcomputer 110 of the result. The contact point 148 can be composed of a switch or the like.

[0135] The card slot 153 is a connector for accepting the memory card 300. The card slot 153 may be not only configured so as to include a mechanical portion for placing the memory card 300, but also be configured so as to include a control portion and/or software for controlling the memory card 300.

[0136] A buffer 111 is a memory used when signal processing is performed in the microcomputer 110. Although a signal stored temporarily in the buffer 111 mainly is image data, a control signal and the like may be stored in the buffer 111. The buffer 111 may be means capable of storing, such as a DRAM (dynamic random access memory), an SRAM (static random access memory), a flash memory, or a ferroelectric memory. The buffer 11 also may be a memory specialized in storage.

[0137] An AF auxiliary light emitting portion 154 is a member that emits auxiliary light when an autofocus operation is performed in a dark photographing place. The AF auxiliary light emitting portion 154 emits light based on the control of the microcomputer 110. The AF auxiliary light emitting portion 154 includes a red LED (light-emitting diode) and the like.

[0138] A remote control receiving portion 155 receives a signal from a remote controller (not shown) and transmits the received signal to the microcomputer 110. The remote control receiving portion 155 typically includes a photodetector that receives infrared light from the remote controller.

[0139] [1-1-3 Configuration of Interchangeable Lens]

[0140] FIG. 4 is a block diagram showing a configuration of the interchangeable lens 200.

[0141] As shown in FIG. 4, the interchangeable lens 200 includes an image pickup optical system. Furthermore, the image pickup optical system and the like of the interchangeable lens 200 are controlled by the CPU 210.

[0142] The CPU 210 controls the operations of actuators such as a zoom motor 231, a diaphragm motor 241, the hand shaking correction unit 250, and a focus motor 261, thereby controlling the image pickup optical system. The CPU 210 sends information representing the states of the image pickup optical system, an accessory placement portion 272, and the like to the camera body 100 via a communication terminal 270. Furthermore, the CPU 210 receives a control signal or the like from the camera body 100, and controls the image pickup optical system and the like based on the received control signal or the like.

[0143] The objective lens 220 is placed closest to the subject side. The objective lens 220 may be movable in an optical axis direction or may be fixed.

[0144] The zoom lens 230 is placed on the image surface side from the objective lens 220. The zoom lens 230 is movable in the optical axis direction. By moving the zoom lens 230, the magnification of the subject image can be varied. The zoom lens 230 is driven with the zoom motor 231. The zoom motor 231 may be any motor such as a stepping motor or a servo motor, as long as it drives at least the zoom lens 230. The CPU 210 monitors the state of the zoom motor 231 or the state of another member to monitor the position of the zoom lens 230.

[0145] The diaphragm 240 is placed on the image surface side from the zoom lens 231. The diaphragm 240 has an aperture with the optical axis at the center. The size of the aperture can be changed by the diaphragm motor 241 and a diaphragm ring 242. The diaphragm motor 241 is synchronized with a mechanism that changes the aperture size of the diaphragm to drive the mechanism, thereby changing the aperture size of the diaphragm. The diaphragm ring 242 also is synchronized with a mechanism that changes the aperture size of the diaphragm to drive the mechanism, thereby changing the aperture size of the diaphragm. An electrical control signal is given to the microcomputer 110 or the CPU 210 by the user, and the diaphragm motor 241 is driven based on the control signal. In contrast, the diaphragm ring 242 receives a mechanical manipulation from the user, and transmits this manipulation to the diaphragm 240. Furthermore, whether or not the diaphragm ring 242 has been operated can be detected by the CPU 210.

[0146] The hand shaking correction unit 250 is placed on the image surface side from the diaphragm 240. The hand shaking correction unit 250 includes a correction lens 251 that corrects hand shaking and an actuator that drives the correction lens 251. The actuator included in the hand shaking correction unit 250 can move the correction lens 251 in a plane orthogonal to an optical axis. A gyrosensor 252 measures an angular speed of the interchangeable lens 200. For convenience, in FIG. 4, although the gyrosensor 252 is shown with one block, the interchangeable lens 200 includes two gyrosensors 252. One of the two gyrosensors measures an angular speed with a vertical axis of the camera 10 being the center. Furthermore, the other gyrosensor measures an angular speed with a horizontal axis of the camera 10 perpendicular to the optical axis being the center. The CPU 210 measures a hand shaking direction and a hand shaking amount of the interchangeable lens 200 based on the angular speed information from the gyrosensor 252. The CPU 210 controls an actuator so as to move the correction lens 251 in a direction of canceling a hand shaking amount. Because of this, the subject image formed with the image pickup optical system of the interchangeable lens 200 becomes a subject image with hand shaking corrected.

[0147] The focus lens 260 is placed closest to the image surface side. The focus motor 261 drives the focus lens 260 in the optical axis direction. This can adjust the focus of the subject image.

[0148] The accessory placement portion 272 is a member that places an accessory such as a light-shielding hood at a tip end of the interchangeable lens 200. The accessory placement portion 272 is composed of mechanical members such as a screw and a bayonet. Furthermore, the accessory placement portion 272 includes a detector that detects whether or not an accessory has been placed. When the accessory is placed, the accessory placement portion 272 notifies the CPU 210 of the placement of the accessory.

[0149] [1-1-4 State of Mirror Box]

[0150] The state in the mirror box 120 in each operation state will be described with reference to FIGS. 1, 5, and 6.

[0151] FIG. 1 is a schematic view showing the state in the mirror box 120 in a mode of observing a subject image using the optical viewfinder. In the present specification, for convenience, this state will be referred to as a "state A". In the state A, the movable mirrors 121a, 121b are positioned in the optical path of the optical signal incident from the interchangeable lens 200. Therefore, a part of the optical signal from the interchangeable lens 200 is reflected by the movable mirror 121a, and the remaining part thereof is transmitted through the movable mirror 121a. The reflected optical signal passes through the focusing glass 125, the prism 126, and the eyepiece 136 to reach the user's eye. Furthermore, the optical signal reflected by the movable mirror 121a is reflected by the focusing glass 125, and a part of the reflected optical signal is incident upon the AE sensor 133. On the other hand, a part of the optical signal transmitted through the movable mirror 121a is reflected by the movable mirror 121b to reach the AF sensor 132. Furthermore, in the state A, a first shutter 123a is closed. Therefore, the optical signal from the interchangeable lens 200 does not reach the CMOS sensor 130. Thus, in the state A, the observation of the subject image using the optical viewfinder, the autofocus operation using the AF sensor 132, and the photometric operation using the AE sensor 133 can be performed. However, the observation of the subject image using the liquid crystal monitor 150, the recording of the image data generated by the CMOS sensor 130, and the autofocus operation using the contrast of the image data generated by the CMOS sensor 130 cannot be performed.

[0152] FIG. 5 is a schematic view showing the state in the mirror box 120 in a mode in which the subject image is input to the CMOS sensor 130. In the specification, for convenience, this state will be referred to as a "state B". In the state B, the movable mirrors 121a, 121b are not positioned in the optical path of the optical signal incident from the interchangeable lens 200. Therefore, the optical signal from the interchangeable lens 200 does not pass through the focusing glass 125, the prism 126, and the eyepiece 136 to reach the user's eye, and does not reach the AF sensor 132 and the AE sensor 133, either. Furthermore, in the state B, the first shutter 123a and the second shutter 123b are opened. Therefore, the optical signal from the interchangeable lens 200 reaches the CMOS sensor 130. Thus, in the state B, contrary to the state A, the observation of the subject image using the liquid crystal monitor 150, the recording of the image data generated by the CMOS sensor 130, and the autofocus operation using the contrast of the image data generated by the CMOS sensor 130 can be performed. However, the observation of the subject image using the optical viewfinder, the autofocus operation using the AF sensor 132, and the photometric operation using the AE sensor 133 cannot be performed. The movable mirrors 121a, 121b, and the first shutter 123a are biased in a direction in which the state A is shifted to the state B by biasing means such as a spring. Therefore, the state A can be shifted to the state B instantaneously, which is preferable for starting exposure.

[0153] FIG. 6 is a schematic view showing the state in the mirror box 120 immediately after the exposure of the subject image with respect to the CMOS sensor 130 is completed. In the present specification, for convenience, this state will be referred to as a "state C". In the state C, the movable mirrors 121a, 121b are not positioned in the optical path of the optical signal incident from the interchangeable lens 200. Therefore, the optical signal from the interchangeable lens 200 does not pass through the focusing glass 125, the prism 126, and the eyepiece 136 to reach the user's eye, and does not reach the AF sensor 132 and the AE sensor 133, either. Furthermore, in the state C, the second shutter 123b is closed while the first shutter 123a is opened. Therefore, the optical signal from the interchangeable lens 200 does not reach the CMOS sensor 130. Thus, in the state C, the observation of the subject image using the liquid crystal monitor 150, the recording of the image data generated by the CMOS sensor 130, the autofocus operation using the contrast of image data generated by the CMOS sensor 130, the observation of the subject image using the optical viewfinder, the autofocus operation using the AF sensor, and the photometric operation using the AE sensor 133 cannot be performed. The second shutter 123b is biased in the closing direction, so that the state B can be shifted to the state C instantaneously. Therefore, the state C is in a state optimum for completing the exposure of the CMOS sensor 130.

[0154] As described above, the state A can be shifted to the state B directly. In contrast, the state B cannot be shifted to the state A without the state C, in terms of the constriction of the mechanism of the mirror box 120. However, this is a technical problem in the mechanism in the mirror box 120, so that a mechanism capable of directly shifting the state B to the state A without the state C may be adopted.

[0155] [1-1-5 Correspondence Between Configuration of Present Embodiment and Configuration of Present Invention]

[0156] The configuration including the focusing glass 125, the prism 126, and the eyepiece 136 is an example of an optical viewfinder of the present invention. The optical system including the objective lens 220, the zoom lens 230, the correction lens 251, and the focus lens 260 is an example of an image pickup optical system of the present invention. The movable mirrors 121a, 121b are examples of a movable mirror of the present invention. The CMOS sensor 130 is an example of an image pickup element of the present invention. The liquid crystal monitor 150 is an example of a display portion of the present invention. The microcomputer 110 is an example of a control portion of the present invention. In this case, the control portion may include the CPU 210 in addition to the microcomputer 110. The LV preview button 140j is an example of a diaphragm adjustment instruction receiving portion of the present invention. The microcomputer 110 is an example of image processing means of the present invention. The full depression manipulation receiving function of the release button 141 is an example of a release portion of the present invention. Similarly, the remote control receiving portion 155 that receives an instruction for the start of capturing an image for recording from the remote controller is an example of the release portion of the present invention. The AF sensor 132 is an example of a distance-measuring portion of the present invention. The configuration including the microcomputer 110, the CPU 210, the focus motor 261, and the focus lens 260 is an example of an autofocus portion of the present invention. The configuration including the focus lens 260 and the focus ring 262 is an example of manual focus means of the present invention. The memory card 300 is an example of a recording portion of the present invention. The halfway depression receiving function of the release button 141 is an example of an AF start instruction receiving portion of the present invention. Similarly, the remote control receiving portion 155 that receives an instruction for the start of autofocusing from the remote controller is an example of an AF start instruction receiving portion of the present invention. The buffer 111 is an example of storage means of the present invention. The supersonic vibration generator 134 is an example of a foreign matter removing portion of the present invention. The diaphragm ring 242 is an example of a diaphragm manipulation portion of the present invention. The menu button 140a is an example of a setting manipulation portion of the present invention. The battery box 143 is an example of a battery accommodating portion of the present invention. The power supply switch 142 is an example of a power supply manipulation portion of the present invention. The external terminal 152 is an example of an output terminal of the present invention. The gyrosensor 252 is an example of a shock detecting portion of the present invention.

[0157] [1-2 Operation of Camera 10]

[0158] The operation of the camera 10 in Embodiment 1 will be described with reference to FIGS. 7-24.

[0159] [1-2-1 Display Operation of Real-time Image]

[0160] The display operation for observing the subject image formed by the interchangeable lens 200 in real time will be described. As the display operation, two operations are set. The first one is an operation using the optical viewfinder, and the second one is an operation using the liquid crystal monitor 150. These operations will be described below in detail.

[0161] In the live view, a subject image only needs to be displayed on the liquid crystal monitor 150 in real time, and the image data displayed on the liquid crystal monitor 150 may or may not be stored simultaneously in storage means such as the memory card 300.

[0162] Furthermore, when the live view is displayed, it is necessary to allow the optical signal from the interchangeable lens 200 to reach the CMOS sensor 130, so that the inside of the mirror box 120 needs to be shifted to the state B shown in FIG. 5. However, even if the microcomputer 110 is set in the live view mode, it is necessary to set the inside of the mirror box 120 to the state A or the state C in addition to the state B, in accordance with each state of the image pickup operation, autofocus operation, automatic exposure control operation, or the like, and a period during which the liquid crystal monitor 150 cannot display a live view also occurs.

[0163] Furthermore, as described above, in the live view, a subject image is displayed on the liquid crystal monitor 250 in real time. However, the term "real time" does not have a strict meaning, and there may be some time delay from an actual operation of a subject as long as the user can feel real time in a common sense. The liquid crystal monitor 150 generally is considered to perform a live view display with a time delay of about 0.1 seconds (this time may be some longer or shorter depending upon hardware and the like of the camera 10), and the case of a delay of about 1 to 5 seconds may be included in the concept of the live view display as a subject image display in real time.

[0164] [1-2-1-1 Operation During Use of Optical Viewfinder]

[0165] The user can switch between the live view mode and the optical viewfinder mode hereinafter, for convenience, referred to as an OVF mode) by sliding the viewfinder switch 140e shown in FIG. 3.

[0166] When the user slides the viewfinder switch 140e to the OVF mode side, the microcomputer 110 is set in the OVF mode. Then, the microcomputer 110 controls the mirror driving portion 122 and the shutter driving portion 124 to shift the inside of the mirror box 120 to the state A shown in FIG. 1. Consequently, the user can observe a subject image in real time through the eyepiece 136. Furthermore, in the state A, as described above, the autofocus operation using the AF sensor 132 and the photometric operation using the AE sensor 133 can be performed.

[0167] [1-2-1-2 Operation During Use of Liquid Crystal Monitor]

[0168] In the OVF mode, when the user slides the viewfinder switch 140e to the live view mode side, the microcomputer 110 is set in the live view mode. More specifically, the microcomputer 110 controls the mirror driving portion 122 and the shutter driving portion 124 to shift the inside of the mirror box 120 to the state B shown in FIG. 5. Because of this, the user can observe the subject image in real time, using the liquid crystal monitor 150.

[0169] [1-2-2 Adjustment of Diaphragm and Display Operation of Real-time Image]

[0170] [1-2-2-1 Operation During Use of Optical Viewfinder]

[0171] In the state A, generally, the diaphragm 240 is opened. When an image pickup operation is started from the state A, the diaphragm 240 is stopped down in accordance with the amount of light incident upon the interchangeable lens 200. Thus, the opened state of the diaphragm 240 varies between the ordinary state of the state A and the image pickup operation. When the opened state of the diaphragm 240 varies, the depth of field becomes different. Therefore, in the ordinary state of the state A, the depth of field when an image for recording is captured cannot be observed. In order to solve this problem, the AV button 140m is provided. The user can observe the depth of field when an image for recording is captured with the optical viewfinder by pressing the AV button 140m. This operation will be described with reference to FIG. 7.

[0172] FIG. 7 is a flowchart illustrating an operation when the AV button 140m is pressed in the OVF mode. In FIG. 7, the microcomputer 110 originally is set in the OVF mode. At this time, the inside of the mirror box 120 is in the state A shown in FIG. 1. Furthermore, the microcomputer 110 monitors whether or not the AV button 140m is pressed (S701). When the user presses the AV button 140m in this state, the microcomputer 110 detects that the AV button 140m has been pressed, and starts measuring an exposure amount (S702). Specifically, the microcomputer 110 allows the AE sensor 133 to measure the light amount of the optical signal that is incident upon the interchangeable lens 200, is reflected by the movable mirror 121b, and is incident upon the AE sensor 133. The microcomputer 110 calculates an appropriate aperture value (f-number) of the diaphragm 240 and a shutter speed while an image for recording is being captured, based on the measurement results and the current opened state of the diaphragm 240. The microcomputer 110 sends the calculated f-number to the CPU 210. The CPU 210 controls the motor 241 based on the received f-number. The motor 241 adjusts the diaphragm 240 based on the control of the CPU 210 (S703).

[0173] In the case where the above operation is performed in the autofocus mode using the AF sensor 132, the autofocus operation as well as the photometric operation can be performed in Steps S702 and S703.

[0174] Thus, by providing the AV button 140m, the depth of field can be observed instantaneously with respect to a subject image while an image for recording is being captured, so that the operability is satisfactory.

[0175] [1-2-2-2 Operation During Use of Liquid Crystal Monitor]

[0176] In the case where the inside of the mirror box 120 is in the state B, generally, the diaphragm 240 is opened. When an image pickup operation is started from the state B, the degree of opening of the diaphragm 240 is controlled to be small in accordance with the amount of light incident upon the interchangeable lens 200. Thus, the opened state of the diaphragm 240 varies between the ordinary state of the state B and the image pickup operation. When the opened state of the diaphragm 240 varies, the depth of field becomes different. Therefore, the depth of field while an image for recording is being captured cannot be observed in the ordinary state of the state B. In order to solve this problem, the stop-down button 140k and the LV preview button 140j are provided. The user can observe the depth of field while an image for recording is being captured in a live view display by pressing the stop-down button 140k or the LV preview button 140j. Each operation will be described with reference to FIGS. 8 and 9.

[0177] FIG. 8 is a flowchart illustrating an operation when the stop-down button 140k is pressed in the live view mode. In FIG. 8, the microcomputer 110 originally is set in the live view mode. At this time, the inside of the mirror box 120 is in the state B shown in FIG. 5. Furthermore, the microcomputer 110 monitors whether or not the stop-down button 140k is pressed (S801). When the user presses the stop-down button 140k in this state, the microcomputer 110 detects that the stop-down button 140k has been pressed, and shifts the state of the mirror box 120 from the state B to the state A via the state C (S802). When the shift to the state A is completed, the measurement by the AE sensor 133 becomes possible, so that the microcomputer 110 starts measuring an exposure amount (S803). Specifically, the microcomputer 110 allows the AE sensor 133 to measure the light amount of the optical signal that is incident upon the interchangeable lens 200, is reflected by the movable mirror 121a, is diffused by the focusing glass 125, and is incident upon the AE sensor 133. The microcomputer 110 calculates an appropriate aperture value (f-number) of the diaphragm 240 and a shutter speed while an image for recording is being captured, based on the measurement results, and the current opened state of the diaphragm 240. The microcomputer 110 sends the calculated f-number to the CPU 210. The CPU 210 controls the motor 241 based on the received f-number. The motor 241 adjusts the diaphragm 240 based on the control of the CPU 210 (S804). After that, the microcomputer 110 returns the inside of the mirror box 120 from the state A to the state B, and restarts a live view operation (S805).

[0178] During a period from Step S802 to Step S804 shown in FIG. 8, a live view display cannot be performed. During this period, no image may be displayed on the liquid crystal monitor 150 (this state is referred to as a "blackout state"), or the setting information on the camera 10 may be displayed, or the information on the current states of-the-automatic exposure control operation and the autofocus operation may be displayed, or the image data displayed in the immediately proceeding live view may be displayed, or the predetermined image data may be displayed. In order to display the image data displayed in the immediately proceeding live view, the microcomputer 110 always needs to save the image data obtained during the live view operation in the buffer 111 temporarily, and update the image data in the buffer 111.

[0179] Furthermore, in the case where the above operation is performed in the autofocus mode using the AF sensor 132, the autofocus operation as well as the automatic exposure control operation are performed in Steps S803 and S804.

[0180] Thus, by providing the stop-down button 140k, in the case of capturing an image for recording, it can be checked instantaneously what depth of field the subject image has, so that the operability is satisfactory.

[0181] FIG. 9 is a flowchart illustrating an operation when the live view preview button 140j is pressed in the live view mode. In FIG. 9, the operations shown in Steps S901 to S905 are similar to those shown in Steps S801 to S805, so that the description thereof will be omitted. When the shift from the state A to the state B is completed in Step S905, the microcomputer 110 displays a region R2 that is a part of the image data generated by the CMOS sensor 130 in an enlarged state as shown in FIG. 10. The part in the screen that is set to be the region R to be enlarged can be changed by operating the cross key 140b and the like.

[0182] Thus, by providing the live view preview button 140j, a place whose depth of field is required to be checked can be enlarged instantaneously, so that the depth of field can be checked easily.

[0183] [1-2-3 Image Pickup Operation of Image for Recording]

[0184] Next, an operation in the case of capturing an image for recording will be described. In order to capture an image for recording, it is necessary to adjust a focus intended by the user previously. As a method for adjusting a focus, there are a manual focus system, a single focus system, a continuous focus system, and the like.

[0185] By operating the focus mode switch 140f shown in FIG. 3, the manual focus mode and the autofocus mode can be switched therebetween. Furthermore, by pressing the menu button 140a to call up a menu screen, either the signal focus mode or the continuous focus mode can be selected in the autofocus mode.

[0186] [1-2-3-1 Manual Focus Image Pickup Operation]

[0187] According to the manual focus system, a focus state is changed in accordance with the operation of the focus ring 262 by the user, and a focus can be set according to the user's preference. On the other hand, according to the manual focus system, if the user is not familiar with a manipulation, there is a problem that time and labor are needed for adjusting a focus. The case of capturing an image while visually recognizing the image through the optical viewfinder and the case of capturing an image while visually recognizing the image on the liquid crystal monitor 150 will be described with reference to FIGS. 11 and 13.

[0188] [1-2-3-1-1 Image Pickup Operation Using Optical Viewfinder]

[0189] FIG. 11 is a flowchart illustrating an operation when an image is captured using the optical viewfinder in the manual focus mode.

[0190] In FIG. 11, in the case of capturing an image in the OVF mode, the inside of the mirror box 120 is in the state A shown in FIG. 1. The user adjusts a focus and a composition while checking a subject image through the eyepiece 136 before capturing the image. The user can adjust a focus by manipulating the focus ring 262 (S1101).

[0191] The microcomputer 110 monitors whether or not the release button 141 has been pressed fully in parallel with Step S1101 (S1102).

[0192] In the case of detecting that the release button 141 has been pressed fully, the microcomputer 110 controls the mirror driving portion 122 and the shutter driving portion 124 to shift the inside of the mirror box 120 from the state A to the state B (S1103).

[0193] Next, the microcomputer 110 exposes an optical signal from the interchangeable lens 200 to the CMOS sensor 130, thereby allowing an image for recording to be captured (S1104).

[0194] When a time corresponding to a shutter speed has elapsed, the microcomputer 100 controls the shutter driving portion 124 so as to close the second shutter 123b, and completes the exposure (State C). After that, the microcomputer 110 controls so that the inside of the mirror box 120 is returned to the state A (S1105).

[0195] The microcomputer 110 receives the image data generated by the CMOS sensor 130, and temporarily stores it in the buffer 111. The image data stored at this time is, for example, image data composed of an RGB component. The microcomputer 110 subjects the image data stored in the buffer 111 to predetermined image processing such as YC conversion processing, resizing processing, and compression processing, thereby generating image data for recording (S1106).

[0196] The microcomputer 110 finally generates an image file pursuant to, for example, an Exif (Exchangeable image file format) specification. The microcomputer 110 allows the generated image file to be stored in the memory card 300 via the card slot 153 (S1107).

[0197] Hereinafter, the image file finally created by the microcomputer 110 will be described.

[0198] FIG. 12 is a schematic view showing a configuration of the image file. As shown in FIG. 12, the image file contains a header portion D1 and an image data portion D2. The image data portion D2 stores image data for recording. The header portion D1 contains various pieces of information storage portion D11 and a thumbnail image D12. The various pieces of information storage portion D11 include a plurality of storage portions storing various pieces of information such as image pickup conditions (e.g., an exposure condition, a white balance condition, an image pickup date, etc.). One of the storage portions includes a finder mode information storage portion D111. The finder mode storage portion D111 stores either "LV" or "OVF" as information. When an image pickup operation is performed in the case where the live view mode is set, the microcomputer 110 stores "LV" information in the finder mode information storage portion D111 of an image file thus generated. In contrast, when an image pickup operation is performed under the condition that the OVF mode is set, the microcomputer 110 stores "OVF" information in the finder mode information storage portion D111 of an image file thus generated.

[0199] Consequently, by analyzing the header portion D1 of the generated image file, it can be understood easily whether the image data contained in the image file is generated in the live view mode or in the OVF mode. Using this, the user can grasp the relationship between the quality of his/her own captured image and the finder mode. This can contribute to the enhancement of a photographic technique and the like.

[0200] Although "LV" or "OVF" is selected to be stored, it may be determined whether or not an image has been captured in the live view mode based on whether or not "LV" or "OVF" is stored, using only either one of "LV" and "OVF". For example, the following may be possible: in the case where an image is captured in the live view mode, "LV" information is stored, and in the case where an image is captured in the OVF mode, no information is stored.

[0201] Furthermore, in Step S1104, various displays can be performed on the liquid crystal monitor 150. For example, at the beginning of Step S1104, the image data generated by the CMOS sensor 130 may be read to the microcomputer 110 prior to the image data for recording, and the read image data may be displayed. Furthermore, the liquid crystal monitor 150 may be set to be a blackout display. Furthermore, a live view image stored in the buffer 111 may be displayed before full depression is performed. Furthermore, the setting information on the camera 10, information representing an operation state, and the like may be displayed.

[0202] Furthermore, in Steps S1103 and S1105, various displays can be performed on the liquid crystal monitor 150. For example, the liquid crystal monitor 150 may be set to be a blackout display. Furthermore, a live view image stored in the buffer 111 may be displayed before full depression is performed. Furthermore, the setting information on the camera 10, information showing an operation state, and the like may be displayed.

[0203] Furthermore, in Steps S1101 and S1102, the inside of the mirror box 120 is in the state A. Therefore, the AF sensor 132 is in a state capable of measuring a distance. The microcomputer 110 can control so as to display the measurement results (a defocus value, etc.) measured in the AF sensor 132 or information based on the measurement results on the liquid crystal monitor 150. Due to such control, the user can check if a focus is adjusted based on the information displayed on the liquid crystal monitor 150 as well as an image during the manual focus manipulation. Therefore, a focus can be adjusted exactly even in the manual manipulation. As a method for displaying measurement results measured by the AF sensor 132 or information based on the measurement results, the display of numerical values, display of a bar graph, display of a line graph, display of a mark representing the degree of a defocus value, and the like are considered.

[0204] [1-2-3-1-2 Image Pickup Operation Using Liquid Crystal Monitor]

[0205] FIG. 13 is a flowchart illustrating an operation when an image is captured using the liquid crystal monitor 150 in the manual focus mode.

[0206] In FIG. 13, in the case of capturing an image in the live view mode, the inside of the mirror box 120 is in the state B shown in FIG. 5. The user adjusts a focus and a composition while checking a subject image through the liquid crystal monitor 150 before capturing the image. In order to adjust a focus, the user manipulates the focus ring 262 (S1301).

[0207] The microcomputer 110 monitors whether or not the release button 141 has been pressed fully in parallel with Step S1301 (S1302).

[0208] In the case of detecting that the release button 141 has been pressed fully, the microcomputer 110 controls the mirror driving portion 122 and the shutter driving portion 124 to shift the inside of the mirror box 120 from the state B to the state A via the state C (S1303).

[0209] The reason why the inside of the mirror box 120 is first set to be in the state A is to disconnect the optical signal incident upon the CMOS sensor 130 with the shutter 123 first and allow the CMOS sensor 130 to prepare for the start of exposure. Examples of the preparation for the start of exposure include the removal of unnecessary charge in each pixel.

[0210] The subsequent operations shown in Steps S1304 to S1306 are similar to those shown in Steps S1103 to S1105 in FIG. 11, so that the description thereof will be omitted.

[0211] When the exposure is completed, and the inside of the mirror box 120 is set to be in the state A (S1306), the microcomputer 110 returns the inside of the mirror box 120 to the state B again, and restarts a live view display (S1307).

[0212] The microcomputer 110 performs image processing and recording of an image for recording in parallel with Step S1307 (S1308, S1309). The operations shown in Steps S1308 and S1309 are similar to those shown in Steps 1106 and 1107 in FIG. 11, so that the detailed description will be omitted.

[0213] During the operations shown in Steps S1303 to S1309, various displays can be performed on the liquid crystal monitor 150. This is similar to the case in the operations shown in Steps S1103 to S1107 in FIG. 11, so that the description will be omitted.

[0214] Furthermore, even in Steps S1308 and S1309, various-displays can be performed on the liquid crystal monitor 150 in addition to the live view display.

[0215] As described above, in Steps S1308 and S1309, since the inside of the mirror box 120 is in the state B, a live view display can be performed. However, in Steps S1308 and S1309, a large part of the control ability of the microcomputer 110 is assigned to image processing and recording processing. Therefore, in Steps S1308 and S1309, it is preferable that the burden on the microcomputer 110, other than the image processing and recording processing, is minimized. In Steps S1308 and S1309, a live view display is avoided. Because of this, the microcomputer 110 is not required to assign the processing ability for a live view display, so that image processing and recording processing can be performed rapidly.

[0216] As the form in which a live view display is not performed, for example, the liquid crystal monitor 150 may be set to be a blackout display. Furthermore, a live view image stored in the buffer 111 may be displayed before full depression is performed. Furthermore, the setting information on the camera 10, information representing an operation state, and the like may be displayed.

[0217] Furthermore, in Steps S1301 and S1302, the inside of the mirror box 120 is in the state B. Therefore, the microcomputer 110 can calculate the degree of contrast of image data generated by the CMOS sensor 130. As the method for calculating the degree of contrast, a method for integrating a high frequency component in a spatial frequency of a brightness signal of image data over the entire surface or in a predetermined range of the image data, and the like are considered. The microcomputer 110 can control so that the degree of contrast of the calculated image data or information based thereon are displayed on the liquid crystal monitor 150 so as to overlap the live view display. Due to such control, the user can check if a focus is adjusted based on the information displayed on the liquid crystal monitor 150 as well as the image during a manual manipulation. Therefore, a focus can be adjusted exactly even in the manual operation. As the method for displaying the degree of contrast of the calculated image data or the information based thereon, the display of numerical values, display of a bar graph, display of a line graph, display of a mark representing the degree of a defocus value, and the like are considered.

[0218] [1-2-3-2 Single Focus Image Pickup Operation]

[0219] According to the single focus system, an autofocus operation is performed in accordance with the halfway depression of the release button 141, and the focus state thus obtained is retained. The retention of the focus state is referred to as "focus lock". The focus lock is kept until image pickup of an image for recording is completed or the halfway depression of the release button 141 is cancelled. The user selects the single focus system to first adjust a focus to a point where the user desires to adjust the focus, and thereafter, adjusts a composition, thereby capturing a favorite image. Hereinafter, an operation in the case of capturing an image using the optical viewfinder and an operation in the case of capturing an image using the liquid crystal monitor 150 will be described with reference to FIGS. 14 and 15.

[0220] [1-2-3-2-1 Image Pickup Operation Using Optical Viewfinder]

[0221] FIG. 14 is a flowchart illustrating an operation when an image is captured using the optical viewfinder in the single focus mode.

[0222] In FIG. 14, in the case of capturing an image in the OVF mode, the inside of the mirror box 120 is in the state A shown in FIG. 1. The user adjusts a focus and a composition while checking a subject image through the eyepiece 136. The microcomputer 110 monitors whether or not the user presses the release button 141 halfway so as to adjust a focus (S1401).

[0223] When the user presses the release button 141 halfway, the autofocus operation based on the measurement results of the AF sensor 132 is started, and the focus state thus obtained is locked (S1402).

[0224] Even after the focus state is locked, the user can adjust a focus manually using the focus ring 262 (S1403).

[0225] During Step S1403, the microcomputer 110 monitors whether or not the release button 141 is pressed fully (S1404).

[0226] When the halfway depression of the release button 141 is cancelled during Steps S1401 to S1404, the microcomputer 110 cancels a focus lock, and returns the state to the one in which autofocus can be performed. Therefore, when the user presses the release button 141 halfway again, a new focus state is locked.

[0227] The subsequent operations in Steps S1405 to S1409 are similar to those in Steps S1103 to S1107 in FIG. 11, so that the description thereof will be omitted. Furthermore, various displays can be performed on the liquid crystal monitor 150 in Steps S1405 to S1409 in the same way as in Steps S1103 to S1107 in FIG. 11, so that the description thereof will be omitted.

[0228] As described above, even after the state is locked once in Step S1402, manual focus adjustment using the focus ring 262 can be performed (S1403), whereby minute focus adjustment can be performed. Therefore, a focus state according to the user's preference can be set.

[0229] In the case where the automatic exposure mode is set, the automatic exposure control operation is performed between Steps S1404 and S1405. Specifically, the automatic exposure control operation is performed during a period from a time when the release button 141 is pressed fully to a time when the inside of the mirror box 120 becomes the state B.

[0230] Herein, the detail of the automatic exposure control operation will be described. The AE sensor 133 performs photometry, and the photometric data thus measured is transmitted to the microcomputer 110. The microcomputer 110 calculates an f-number and a shutter speed based on the obtained photometric data. The microcomputer 110 transmits the calculated f-number to the CPU 210. Furthermore, the microcomputer 110 prepares so as to control the shutter driving portion 124 and the CMOS sensor 130 so as to obtain the calculated shutter speed. The CPU 210 controls the motor 241 based on the received f-number. The motor 241 adjusts an aperture size of the diaphragm 240 in accordance with the control of the CPU 210. The above operations are performed during a period from a time when the release button 141 is pressed fully to a time when the inside of the mirror box 120 becomes the state B.

[0231] The timing at which the automatic exposure control operation is performed is not limited to the above timing. For example, in Step 1302, the automatic exposure control based on the measurement results of the AE sensor 133 may be performed together with the autofocus control.

[0232] Furthermore, the automatic exposure control operation may be performed after the autofocus control is completed. When the AF sensor 132 measures a distance, it is necessary to open the diaphragm 240 to, for example, F6.5 or more. The reason for this is to allow a line sensor in the AF sensor 132 to form a subject image sufficiently. The measurement by the AF sensor can be completed exactly by adjusting the aperture size of the diaphragm 240 after the completion of the autofocus control.

[0233] Furthermore, after the measurement of the AF sensor 132, the autofocus control and the adjustment of an aperture size of the diaphragm 240 may be performed in parallel. Because of this, the diaphragm 240 is driven without waiting for the completion of the autofocus operation, so that a time required for setting the diaphragm 240 can be shortened.

[0234] [1-2-3-2-2 Image Pickup Operation Using Liquid Crystal Monitor]

[0235] FIG. 15 is a flowchart illustrating an operation when an image is captured using the liquid crystal monitor 150 in the single focus mode.

[0236] In FIG. 15, in the case of capturing an image in the live view mode, the inside of the mirror box 120 originally is in the state B shown in FIG. 5. The user adjusts a focus and a composition while checking a subject image through the liquid crystal monitor 150 before capturing the image. The microcomputer 110 monitors whether or not the user presses the release button 141 halfway so as to adjust a focus (S1501).

[0237] When the user presses the release button 141 halfway, the microcomputer 110 starts a timer in the microcomputer 110 (S1502).

[0238] The microcomputer 110 shifts the inside of the mirror box 120 from the state B to the state A via the state C in parallel with Step S1502 (S1503), and starts the autofocus operation based on the measurement results of the AF sensor 132 and locks the focus state thus obtained (S1504). The reason why the inside of the mirror box 120 is shifted to the state A in S1503 is to measure a distance with the AF sensor 132.

[0239] Even after the focus is locked, manual focus adjustment using the focus ring 262 can be performed (S1505).

[0240] The microcomputer 110 monitors whether or not the release button 141 is pressed fully while the focus ring 262 is being manipulated (S1506).

[0241] The microcomputer 110 monitors whether or not the release button 141 is pressed fully before a predetermined time elapses after the halfway depression (S1507). When the release button 141 is pressed fully before a predetermined time elapses after the release button 141 is pressed halfway, the microcomputer 110 is shifted to Step S1512, and starts an image pickup operation immediately. On the other hand, when a predetermined time elapses after the halfway depression with the release button 141 is not pressed fully, the microcomputer 110 is shifted to Step S1508.

[0242] In Step S1508, the microcomputer 110 shifts the inside of the mirror box 120 from the state A to the state B. Because of this, the camera 10 can display a subject image on the liquid crystal monitor 150 under the condition that a focus is locked. Therefore, the user can determine a favorite composition by watching an image displayed on the liquid crystal monitor 150 while keeping the focus in a favorite state.

[0243] Next, the microcomputer 110 monitors whether or not the release button 141 is pressed fully (S1510).

[0244] While Step S1510 is being performed, a focus state can be changed manually using the focus ring 262 in the same way as in Step S1504 (S1509).

[0245] During Steps S1501 to S1510, in the same way as in Steps S1401 to S1404 in FIG. 14, when the halfway depression of the release button 141 is cancelled, the microcomputer 110 cancels a focus lock, and returns the state to the one in which an autofocus can be performed again. Therefore, when the release button 141 is pressed halfway again, a new focus state is locked.

[0246] The subsequent operations in Steps S1511 to S1517 are similar to those in S1303 to S1309 in FIG. 13, so that the description thereof will be omitted.

[0247] As described above, merely by pressing the release button 141 halfway, after the movable mirror 121 is moved down to measure a distance, the camera 10 returns to the live view mode. Because of this, with a simple manipulation of pressing the release button 141 halfway, the operations from the autofocus operation using the AF sensor 132 to the live view display can be performed easily. Therefore, the user can adjust a composition in the live view display when a subject is focused by a simple manipulation.

[0248] Furthermore, when the user desires to change a composition while watching the liquid crystal monitor 150 after determining a focus state, the user only need to wait until a predetermined time elapses after pressing the release button 141 halfway. On the other hand, in the case of pressing the release button 141 fully immediately after pressing it halfway, an image starts being captured without a live view display (S1508-S1511 are skipped in S1506), so that a time from the halfway depression to the start of capturing an image can be shortened. This is because the movable mirror is prevented from being moved up/down unnecessarily. Therefore, the user can capture a favorite image without letting a shutter timing slip away.

[0249] In Steps S1511 to S1517, various displays can be performed on the liquid crystal monitor 150 in the same way as in Steps S1103 to S1107.

[0250] Furthermore, a live view cannot be displayed in the autofocus operation (S1504) and the image pickup operation (S1513). Alternatively, even when a live view can be displayed for a short period of time, it is difficult to display it continuously. This is because the movable mirror 121 is moved down in the autofocus operation (S 1504). Furthermore, in the image pickup operation (S1513), it is difficult for the CMOS sensor 130 to output image data during exposure. Thus, it is considered that an image other than a live view is displayed on the liquid crystal monitor 150 in these cases. In this case, it is preferable to vary a method for displaying an image on the liquid crystal monitor 130 or a method for not displaying an image on the liquid crystal monitor 130 between the autofocus operation (S1504) and the image pickup operation (S1513). The display on the liquid crystal monitor 130 varies, so that it is easy to recognize whether the autofocus operation or the image pickup operation is being performed. Because of this, the movable mirror 121 is moved up and down in the autofocus operation and the image pickup operation. Therefore, the problem that the user is likely to confuse both the operations since the patterns of sounds generated from the mirror box 120 are similar to each other can be solved. There are various display or non-display examples. For example, during the autofocus operation, image data stored immediately before in the buffer 111 may be displayed on the liquid crystal monitor 150, and during the image pickup operation, the liquid crystal monitor 150 may be set to be a blackout (nothing is displayed), or vice versa. Furthermore, during the autofocus operation, information representing it (e.g., a message "during auto-focusing") may be displayed on the liquid crystal monitor 150, and during the image pickup operation, information representing it (e.g., a message "during capturing of an image" ) may be displayed on the liquid crystal monitor 150.

[0251] Furthermore, the timing at which the automatic exposure control operation is performed can be set variously. This point is similar to that described in "1-2-3-2-1 Image pickup operation using optical viewfinder".

[0252] Furthermore, in the above, it is determined whether or not a live view mode is recovered based on whether or not a predetermined time elapses from halfway depression. However, the present invention is not limited thereto. For example, it may be determined whether or not a live view mode is recovered based on whether or not the full down depression is performed before or after the completion of an autofocus operation. More specifically, the following may be possible. In the case where an autofocus operation is started in accordance with halfway depression, and full depression is performed before the completion of the autofocus operation, the camera 10 is shifted directly to an image pickup operation of an image for recording. On the other hand, in the case where full depression is not performed before the completion of the autofocus operation, the camera 10 is first shifted to a live view mode, and thereafter, is shifted to an image pickup operation of an image for recording when full depression is performed.

[0253] [1-2-3-3 Continuous Focus Image Pickup Operation]

[0254] According to the continuous focus system, an autofocus operation is performed in accordance with halfway depression of the release button 141, and during the halfway depression, the autofocus operation is repeated continuously to update a focus state. The update of the focus state is continued until the image pickup of an image for recording is finished or the halfway depression of the release button 141 is cancelled. The user can focus a particular subject repeatedly by selecting the continuous focus system. Therefore, the continuous focus system is particularly advantageous for capturing a moving subject.

[0255] [1-2-3-3-1 Operation During Image Pickup Using Optical Viewfinder]

[0256] FIG. 16 is a flowchart illustrating an operation when an image is captured using an optical viewfinder in the continuous focus mode.

[0257] In FIG. 16, in the case of capturing an image in the OVF mode, the inside of the mirror box 120 is in the state A shown in FIG. 1. The user adjusts a focus and a composition while checking a subject image through the eyepiece 136 before capturing the image. The microcomputer 110 monitors whether or not the user presses the release button 141 halfway so as to adjust a focus (S1601).

[0258] When the user presses the release button 141 halfway, the autofocus operation based on the measurement results of the AF sensor 132 is started (S1602).

[0259] Then, while the user is pressing the release button 141 halfway, the CPU 210 updates a focus state based on the measurement results of the AF sensor 132 regarding the distance to the subject. During this time, the microcomputer 110 monitors whether or not the release button 141 is pressed fully (S1603).

[0260] The subsequent operations in Steps S1604 to S1608 are similar to those in Steps S1103 to S1107 in FIG. 11, so that the description thereof will be omitted. Furthermore, in Steps S1604 to S1608, various displays can be performed on the liquid crystal monitor 150 in the same way as in Steps S1103 to S1107 in FIG. 11, so that the description thereof will be omitted.

[0261] When the halfway depression is cancelled before the user presses the release button 141 fully, the CPU 210 stops the autofocus operation based on the measurement results of the AF sensor 132.

[0262] Furthermore, the timing at which the automatic exposure control operation is performed can be set variously. This point is the same as that described in "1-2-3-2-1 Image pickup using optical viewfinder".

[0263] [1-2-3-3-2 Image Pickup Operation Using Liquid Crystal Monitor]

[0264] FIG. 17 is a flowchart illustrating an operation when an image is captured using the liquid crystal monitor 150 in the continuous focus mode. In the present operation, the autofocus operation uses both an autofocus operation of a system using image data generated by the CMOS sensor 130 and an autofocus of a system using the measurement results of the AF sensor 132.

[0265] Herein, as an autofocus operation of a system using the image data generated by the CMOS sensor 130, for example, an autofocus operation of a so-called "mountain-climbing system" is considered. According to the autofocus operation of the mountain-climbing system, a contrast value of image data generated by the CMOS sensor 130 is monitored while the focus lens 260 is operated minutely, and the focus lens is positioned in a direction of a large contrast value.

[0266] In FIG. 17, in the case of capturing an image in a live view mode, the inside of the mirror box 120 originally is in the state B shown in FIG. 5. The user adjusts a focus and a composition while checking a subject image through the liquid crystal monitor 150 before capturing the image. The microcomputer 110 monitors whether or not the user presses the release button 141 halfway so as to adjust a focus (S1701).

[0267] When the user presses the release button 141 halfway, the microcomputer 110 starts the autofocus operation based on the contrast of the image data generated by the CMOS sensor 130 (S1702).

[0268] While the user is pressing the release button 141 halfway, the CPU 210 updates a focus state based on the above-mentioned contrast. During this time, the microcomputer 110 monitors whether or not the release button 141 is pressed fully (S1703).

[0269] Upon detecting that the release button 141 has been pressed fully in Step S1703, the microcomputer 110 shifts the inside of the mirror box 120 from the state B to the state A via the state C (S1704).

[0270] Next, the microcomputer 110 controls so that an autofocus operation is performed based on the measurement results of the AF sensor 132 (S1705).

[0271] Thereafter, the operations from the image pickup operation to the recording operation are performed (S1706-S1711). These operations are similar to those in Steps S1512 to S1517 in FIG. 15, so that the detailed description thereof will be omitted.

[0272] As described above, by using the autofocus operation based on the image data generated by the CMOS sensor 130 and the autofocus operation based on the measurement results of the AF sensor 132, even when the movable mirror 121 is not positioned in an optical path and when the movable mirror 121 is positioned in the optical path, an autofocus operation can be performed.

[0273] Furthermore, while the release button 141 is being pressed halfway, the autofocus operation based on the image data generated by the CMOS sensor 130 is performed, whereby a live view can be displayed on the liquid crystal monitor 150 continuously while the continuous focus operation is being performed.

[0274] Furthermore, the autofocus operation based on the measurement results of the AF sensor 132 is performed after the release button 141 is pressed fully, so that a focus can be adjusted more exactly immediately before an image is captured. Particularly, in the case where a subject moving fast is captured, a time from the last autofocus operation (S1705) to the image pickup operation (S1707) is short, so that a focus can be adjusted easily. More specifically, when the operation is shifted to an image pickup operation of an image for recording in the CMOS sensor 130 under the condition that the continuous focus operation is being performed based on the image data generated by the CMOS sensor 130, the movable mirror 121 is allowed to enter the optical path before the operation is shifted to the image pickup operation, whereby the autofocus operation based on the measurement results of the AF sensor 132 is performed.

[0275] When the halfway depression is cancelled before the user presses the release button 141 fully, the CPU 210 stops the autofocus operation based on the contrast.

[0276] Furthermore, in Step S1705, the photometric operation in the AF sensor 133 may be performed together with the autofocus operation.

[0277] Furthermore, various displays can be performed on the liquid crystal monitor 150 in Steps S1706 to S1711 in the same way as in Steps S1103 to S1107.

[0278] [1-2-4 Autofocus Operation During Shift to Live View Mode]

[0279] The camera 10 in Embodiment 1 performs an autofocus operation when the OVF mode is switched to the live view mode. FIG. 18 is a flowchart illustrating an autofocus operation during shift to the live view mode.

[0280] In FIG. 18, during the operation in the OVF mode, the microcomputer 110 monitors whether or not the viewfinder switch 140e can be switched (S1801).

[0281] When the viewfinder switch 140e is switched to the live view mode, the microcomputer 110 controls so that an autofocus operation is performed based on the measurement results of the AF sensor 132 (S1802).

[0282] When the autofocus operation is completed, the microcomputer 110 shifts the inside of the mirror box 120 from the state A to the state B (S1803). Then, the microcomputer 110 starts an operation in the live view mode.

[0283] As described above, the autofocus operation is performed when the OVF mode is switched to the live view mode, so that the observation of a subject image can be started on the liquid crystal