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Digital Camera Patent Abstract
The digital camera module with an auto-focusing function includes
a lens barrel (10), a lens mount (20) and an image pick-up sensor
(50). The lens barrel has at least one lens (14) positioned therein.
The lens mount includes a first frame (22), a second frame (24),
an adjusting mechanism, and a driving mechanism (40). The first
frame and the second frame are spaced apart. The lens barrel is
mounted on and/or within one of the first frame and the second frame.
The adjusting mechanism is connected with the first frame and the
second frame and configured to be extendable. The magnetism-based
driving mechanism is configured to drive and selectably extend the
adjusting mechanism. The image pick-up sensor is disposed on the
other one of the first frame and the second frame.
Digital Camera Patent Claims
1. A digital camera module with an auto-focusing function, comprising:
a lens barrel having at least one lens positioned therein; a lens
mount including: a first frame; a second frame, the first frame
and the second frame being spaced apart, the lens barrel being carried
by one of the first frame and the second frame; an adjusting mechanism
connected with the first frame and the second frame and configured
to be extendable; and a driving mechanism configured to drive and
selectably extend the adjusting mechanism; an image pick-up sensor
disposed on the other one of the first frame and the second frame,
the image pick-up sensor being configured for receiving light from
the at least one lens, the light corresponding to an image.
2. The digital camera module as claimed in claim 1, wherein the
first frame includes a first plate and at least two sliding portions
symmetrically extending from a first side of the first plate toward
the second frame, the lens barrel being mounted on the first plate.
3. The digital camera module as claimed in claim 2, wherein the
second frame includes a second plate and two hollow support portions
symmetrically extending from a first side of the second plate toward
the first plate, each hollow support portion aligning with and receiving
therein a corresponding sliding portion.
4. The digital camera module as claimed in claim 3, wherein the
adjusting mechanism includes at least two extendable shafts, each
shaft include a first shaft arm and a second shaft arm pivotally
connected with each other via a hinge.
5. The digital camera module as claimed in claim 4, wherein each
first shaft arm is pivotally connected with the first plate, and
each second shaft arm is pivotally connected with the second plate.
6. The digital camera module as claimed in claim 3, wherein the
driving mechanism includes a first and second electric magnets capable
of aligning with each other, each electric magnet being secured
on the hinge of a respective extendable shaft.
7. The digital camera module as claimed in claim 6, further comprising
a third and a fourth electric magnets capable of aligning with the
first and the second electric magnets, the third and the fourth
electric magnets being secured on one respective hollow support
portion.
8. The digital camera module as claimed in claim 6, further comprising
two resilient members respectively disposed between the first plate
and a corresponding hollow support portion, one end of the respective
resilient member resisting the first plate, the other end of the
respective resilient member resisting the corresponding hollow extending
portion.
9. The digital camera module as claimed in claim 8, wherein the
respective resilient member is a coil spring, the coil spring being
placed around the corresponding sliding portion of the first frame.
10. The digital camera module as claimed in claim 2, wherein each
sliding portion is a post.
11. The digital camera module as claimed in claim 3, wherein each
hollow support portion is a sleeve.
12. The digital camera module as claimed in claim 2, wherein the
first plate defines a through hole configured for receiving the
lens barrel therein.
13. The digital camera module as claimed in claim 1, wherein the
driving mechanism is configured for selectively using at least one
of magnetic attraction and magnetic repulsion for the force needed
to move the adjusting mechanism.
Digital Camera Patent Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to a digital camera
module with an auto-focusing function and, more particularly, to
a small-sized digital camera module with an auto-focusing function
and to a portable electronic device, such as a mobile phone or a
Personal Digital Assistant (PDA), having such a camera module mounted
therein.
[0003] 2. Discussion of the Related Art
[0004] Recently, with the development of wireless communication
technologies, there are many cases where digital cameras are mounted
in, e.g., mobile phones or PDAs.
[0005] Generally, digital cameras are image recording media capable
of photographing a plurality of still images without using film.
Such a digital camera typically uses an image pickup device, which
is a kind of semiconductor device, such as a Charge Coupled Device
(CCD) or Complementary Metal Oxide Semiconductor (CMOS). In the
digital camera, an object image formed on the image pickup device
through a lens is converted into an electrical signal by the image
pickup device, and the electrical signal is stored as a digital
signal, e.g., in the camera unit or in a mobile phone or PDA in
which the digital camera is mounted.
[0006] Since the digital camera is desirably mounted in small mobile
phones or PDAs, a fixed focus lens module is usually used to facilitate
mounting thereof within such a small mobile device. However, images
photographed by a digital camera module with a fixed focus lens
module tend to be poor in quality. It is partly due to the fixed
focus lens, which is incapable of adjusting focal length to make
a clearer image.
[0007] What is needed, therefore, is a digital camera module with
an auto-focusing function, which satisfies the needs for performance
enhancement, downsizing, and power saving.
SUMMARY OF THE INVENTION
[0008] A digital camera module with auto-focusing function is adapted
for use in a foldable electronic device. The digital camera module
with an auto-focusing function comprises lens barrel, a lens mount,
and an image pick-up sensor. The lens barrel has at least one lens
positioned therein. The lens mount includes a first frame, a second
frame, an adjusting mechanism, and a driving mechanism. The first
frame and the second frame are spaced apart. The lens barrel is
mounted on and/or within one of the first frame and the second frame
and is thus carried thereby The adjusting mechanism is connected
with the first frame and the second frame and is configured to be
extendable. The driving mechanism is configured to drive and selectably
extend the adjusting mechanism. The image pick-up sensor is disposed
on the other one of the first frame and the second frame. The image
pick-up sensor is configured for receiving light from the at least
one lens, the light corresponding to an image being received by
the digital camera module.
[0009] A main advantage of the digital camera module with auto-focusing
function is that driving of the telescopic movement of the lens
barrel is achieved by changing an environmental magnetic field of
the adjusting mechanism. The digital camera module thus has a simple,
compact structure.
[0010] Other advantages and novel features will become more apparent
from the following detailed description when taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Many aspects of the digital camera module with an auto-focusing
function can be better understood with reference to the following
drawings. The components in the drawings are not necessarily to
scale, the emphasis instead being placed upon clearly illustrating
the principles of the present digital camera module with an auto-focusing
function. Moreover, in the drawings, like reference numerals designate
corresponding parts throughout the several views.
[0012] FIG. 1 is an schematic view of a digital camera module in
a first position with an auto-focusing function, in accordance with
a first preferred embodiment;
[0013] FIG. 2 is similar to FIG. 1, but shows a second position
of the digital camera module,
[0014] FIG. 3 is an schematic view of a digital camera module in
a first position with an auto-focusing function, in accordance with
a second preferred embodiment; and
[0015] FIG. 4 is similar to FIG. 3, but shows a second position
of the digital camera module.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0016] Referring now to the drawings, FIG. 1 shows a digital camera
module 100 with an auto-focusing function, according to a first
preferred embodiment. The digital camera module 100 is adapted for
use in portable electronic device (not shown), such as a mobile
phone or a Personal Digital Assistant (PDA), but the compact nature
thereof could prove useful in compact digital camera units or digital
camcorders, as well. The digital camera module 100 includes a lens
module 10, a lens mount 20, and an image pickup sensor 50. The lens
module 10 is mounted on the lens mount 20 and can be moved relative
to the image pickup sensor 50, via the lens mount 20.
[0017] The lens module 10 includes a lens barrel 12 and a plurality
of lenses 14 received in the lens barrel 12. The lens barrel 12
is a hollow cylinder with an open end 120. The lens barrel 12 includes
a cylindrical body 122 and an enlarged top portion 124, integrally
formed with the cylindrical body 122. The enlarged top portion 124
has a hole 126 defined therein so that light beams associated with
the image being received can be transmitted therethrough. The lenses
14 are received in the hollow cylindrical body 122 of the lens barrel
12.
[0018] The lens mount 20 includes a top frame 22, a bottom frame
24, an adjusting mechanism 30, and a driving mechanism 40. The top
frame 22 can move away or toward the bottom frame 24 via the adjusting
mechanism 30 under the effect of the driving mechanism 40.
[0019] The top frame 22 includes a top plate 222 and two posts
224 symmetrically extending downwardly from opposing sides of the
bottom of the top plate 222. The top plate 222 has a through hole
226 defined in the middle portion thereof The size of the through
hole 226 corresponds to the outer diameter of the cylindrical body
122 of the lens barrel 12 so that the cylindrical body 122 of the
lens barrel 12 extends therethrough. Accordingly, the cylindrical
body 122 of the lens barrel 12 is received within the through hole
226 of the top plate 222 and is mounted therein, e.g., via screw
threading, adhesive, and/or metallurgical bonding.
[0020] The bottom frame 24 includes a bottom plate 242 and two
sleeves 244 symmetrically extending upwardly from opposing sides
of the top thereof. Each sleeve 244 is a hollow cylinder with an
open end 246 opposite to the bottom plate 242. The inner diameter
of each sleeve 244 is larger than the diameter of each post 224
so that the post 224 can be inserted into the sleeve 244 via the
open end 246. Accordingly, each post 224 is slidably movable/retractable
within the corresponding sleeve 244. The image pick-up sensor 50
is disposed on the bottom plate 242 and aligns with the open end
120 of the lens barrel 112 of the lens module 10. As such, the lens
barrel 12 of the lens module 10 is capable of routing the input
light beams, corresponding to an image being photographed, to the
image pick-up sensor 50. The image pick-up sensor 50 can, for example,
be a Complementary Metal-Oxide Semiconductor (CMOS) type sensor
or a Charge Coupled Device (CCD). The image pick-up sensor 50 is
electrically connected with a printed circuit board (not labeled)
so that an image signal can be output to a signal processing unit
(not labeled).
[0021] The adjusting mechanism 30 includes a first extendable shaft
32 and a second extendable shaft 34. The first extendable shaft
32 and the second extendable shaft 34 are mirror-symmetrically disposed
between the top plate 222 and the bottom plate 242. The first extendable
shaft 32 includes a first shaft arm 322 and a second shaft arm 324.
The first shaft arm 322 is pivotally connected with the top plate
222 of the lens mount 20, via a first hinge 326. The second shaft
arm 324 is pivotally connected with the bottom plate 242 of the
lens mount 20, via a second hinge 328. The first shaft arm 322 is
pivotally connected with the second shaft arm 324, via a third hinge
330. The second extendable shaft 34 also includes a first shaft
arm 342 and a second shaft arm 344. The first shaft arm 342 is pivotally
connected with the top plate 222 of the lens mount 20, via a fourth
hinge 346. The second shaft arm 344 is pivotally connected with
the bottom plate 242 of the lens mount 20, via a fifth hinge 348.
The first shaft arm 342 is pivotally connected with the second shaft
arm 344, via a sixth hinge 350.
[0022] The driving mechanism 40 is configured for selectively using
at least one of magnetic attraction and repulsion for the force
needed to move the adjusting mechanism 30. The driving mechanism
40 includes a first electric magnet 42, a second electric magnet
44, a third electric magnet 46, and a fourth electric magnet 48.
The first and the second electric magnet 42, 44 are respectively
pivotally connected to the first hinge 326, 346 of the adjusting
mechanism. The third and the fourth electric magnet 46, 48 are secured
on one respective sleeve 244. The first electric magnet 42, the
second electric magnet 44, the third electric magnet 46, and the
fourth electric magnet 48 are arranged to align with each other.
[0023] In use, the digital camera module 100 is equipped within
a portable electronic device (not shown), such as mobile phone,
and the driving mechanism 40 is electrically connected with a circuit
board of the mobile phone for capturing electrical power. When the
driving mechanism 40 is induced with a current flow, a magnetic
field is produced. Thus, a magnetic force that may be a magnetic
attractive force or a magnetic repulsive force is generated between
the four electric magnets 42, 44, 46, 48. When the pole arrangement
of the four electric magnets is N pole, S pole, S pole, N pole,
S pole, N pole, N pole, S pole from the left to the right, the first
extendable shaft 32 and the second extendable shaft 34 adjoin each
other because of a magnetic attractive force between the first electric
magnet 42 and the second electric magnet 44 and because of a simultaneous
magnetic repulsive force between the third electric magnet 46 and
the first electric magnet 42 and between the second electric magnet
44 and the fourth electric magnet 48. Accordingly, the top plate
222 of the top frame 22 has a first position relative to the bottom
frame 24 (i.e., a minimum separation distance), as shown in FIG.
1, and the lens module 10 has a first focus length.
[0024] Referring to FIG. 2, when the pole arrangement of the four
magnets is S pole, N pole, S pole, N pole, N pole, N pole, N pole,
S pole from the left to the right, the first extendable shaft 32
and the second extendable shaft 34 move away from each other because
of a magnetic repulsive force between the first electric magnet
42 and the second electric magnet 48 and, concurrently, because
of a magnetic attractive force between the first electric magnet
42 and the third electric magnet 46 and between the second electric
magnet 44 and the fourth electric magnet 48. The posts 224 move
upwardly in the corresponding sleeves 244, and the top plate 222
moves away from the bottom plate 242. Accordingly, the top plate
222 of the top frame 22 has a second position relative to the bottom
frame 24 (i.e., a maximum separation distance), and the lens module
10 has a second focus length. Thus, the focusing purpose is achieved
by changing the distance between the image pick-up sensor 50 and
the lenses 14 in the lens barrel 12.
[0025] It can be understood that the top plate 222 may have one
or more further positions between the first position and the second
position by changing the current flow, thus changing the pole arrangement
of the four electric magnets 42, 44, 46, 48. Thus, the magnetic
force between them changes accordingly, which makes a distance between
the first extendable shaft 32 and the second extendable shaft 34
changed. Accordingly, intermediate focal positions between the two
illustrated in FIGS. 1 and 2 may be achievable using the present
focusing system.
[0026] A main advantage of the digital camera module 100 with an
auto-focusing function is that driving the telescopic movement of
the lens barrel 12 is achieved by changing environmental magnetic
field of the four electric magnets 42, 44, 46, 48. The digital camera
module 100 thus has a simple, compact structure.
[0027] Referring to FIG. 3, a digital camera module 200 is provided
according to a second preferred embodiment. The structure of the
digital camera module 200 is essentially same as the digital camera
module 100 except that driving mechanism 60 is used in place of
the driving mechanism 40. The driving mechanism 60 only includes
a first electric magnet 62, a second electric magnet 64, and two
springs 66 as a resilient member. The first and the second electric
magnets 62, 64 are secured on one respective sleeve 244. Each spring
66 is advantageously coil spring, although it is to be understood
that other spring configurations could potentially be employed.
The inner diameter of the spring 66 is larger than the diameter
of the post 224 of the top frame 22 to permit movement therebetween.
The outer diameter of each spring 66 is less than that of the sleeve
244, thereby allowing the top/upper distal end of each sleeve 244
to act as a stop limit surface for the corresponding spring 66.
Each spring 66 is placed around one respective post 224. One end
of each spring 66 resists the bottom of the top plate 222 of the
top frame 22, and the other end of each spring 66 resists the top
of the corresponding sleeve 244.
[0028] In use, the digital camera module 200, like the digital
camera module 100, can be equipped within a portable electronic
device, such as mobile phone, or can be part of a digital camera
unit or camcorder. The driving mechanism 60 is electrically connected
with a circuit board of the mobile phone or camera unit for capturing
electrical power. The spring 66 is compressed to a maximum state
(i.e., a minimum spring height), and the top plate 222 is urged
by a maximum spring force of the spring 66. The driving mechanism
60 can be induced with a current flow, and a magnetic field is produced.
Thus, a magnetic force that may be a magnetic attractive force or
a magnetic repulsive force is generated between the two electric
magnets 62, 64.
[0029] When the pole arrangement of the two electric magnets is
S pole, N pole, S pole, N pole from the left to the right, a magnetic
attractive force is generated between the two electric magnets 62,
64, which makes the first extendable shaft 32 and the second extendable
shaft 34 move toward each other. When the magnetic attractive force
meets or exceeds the maximum spring force of the spring 66, the
first extendable shaft 32 and the second extendable shaft 34 are
able contact with each other, as shown in FIG. 3. Accordingly, the
top plate 222 of the top frame 22 has a first position relative
to the bottom frame 24 (i.e., a minimum separation distance), as
shown in FIG. 3, and the lens module 10 has a first focus length.
[0030] Conversely, when the pole arrangement of the two electric
magnets is S pole, N pole, N pole, S pole from the left to the right
by changing a direction of the current flow, a magnetic repulsive
force is generated between the two electric magnets 62, 64. The
posts 224 move upwardly in the corresponding sleeves 244, and the
top plate 222 will move away the bottom plate 242 of the bottom
frame 24 under the maximum spring force of the spring 66 and the
magnetic repulsive force, as shown in FIG. 4. Accordingly, the top
plate 222 of the top frame 22 has a second position relative to
the bottom frame 24 (i.e., a maximum separation distance), as shown
in FIG. 4, and the lens module 10 has a second focus length. Thus,
the focusing purpose is achieved by changing the distance between
the image pick-up sensor 50 and the lenses 14 in the lens barrel
12. It can be seen that when the driving mechanism 60 is not induced
with a current flow, no magnetic field is produced. When there is
no magnetic force produced between the first and the second electric
magnets 62, 64, the posts 224, under the maximum spring force of
the spring 66, move upwardly in the corresponding sleeves 244, and
the top plate 222 also will move away the bottom plate 242 of the
bottom frame 24.
[0031] It can be understood that the top plate 222 of the top frame
22 may have at least a third position between the first position
and the second position by changing a value of the current flow,
thus changing attractive force between the two electric magnets
62, 64. Thus, as the magnetic force between them changes accordingly,
the distance between the first extendable shaft 32 and the second
extendable shaft 34 changes.
[0032] In an alternative embodiment of the digital camera module
200, the spring 60 can be omitted. In such an embodiment, when there
is not any magnetic force produced between the first and the second
electric magnets 62, 64, the top plate 222 has a first position
where the top plate 222 of the top frame 23 contacts with the sleeves
244 of the bottom frame 24 and is supported thereby. When the first
and the electric magnets 62, 66 are induced with a current flow,
a magnetic field is produced. When a magnetic repulsive force is
generated between the two electric magnets 62, 64, the extendable
shaft 32 and the extendable shaft 34 move away from each other under
the magnetic repulsive force between the two electric magnets 62,
64. Thus, the posts 224 move upwardly in the corresponding sleeves
244, and the top plate 222 moves away the bottom plate 242 of the
bottom frame 24 because of the urging of the extendable shafts 32,
34. Accordingly, the top plate 222 has a second position.
[0033] In a further alternative embodiment, each post 224 can be
another extending portion such as a projecting wall extending from
the top plate 222 of the top frame 22. The sleeve 244 can be another
hollow support portion such as a hollow sidewall extending from
the bottom plate 242 of the bottom frame 24. The size of the projecting
wall is, in such an embodiment, less than that of the hollow sidewall.
The projecting wall can be inserted into the hollow sidewall and
is able to move relative to the hollow sidewall.
[0034] It is to be understood, however, that even though numerous
characteristics and advantages of the present embodiments have been
set forth in the foregoing description, together with details of
the structures and functions of the embodiments, the disclosure
is illustrative only, and changes may be made in detail, especially
in matters of shape, size, and arrangement of parts within the principles
of the invention to the full extent indicated by the broad general
meaning of the terms in which the appended claims are expressed.
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