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Digital Camera Patent Abstract
A digital camera module (100) includes a lens barrel (20), a lens
holder (22), an image pick-up module (26), and a protective member.
The lens barrel defines a central hollow, and has at least one lens
(202) received therein. The lens holder defines a central hollow.
The lens barrel is movably received in the lens holder along an
axis of the lens holder. The image pick-up module is arranged to
receive light from the lenses. The protective member is configured
for preventing dust and/or particle contamination associated with
a relative movement of the lens barrel and the lens holder falling
onto the image pick-up module.
Digital Camera Patent Claims
1. A digital camera module, comprising: a lens barrel defining a
central hollow, and having at least one lens received therein; a
lens holder defining a central hollow, the lens barrel movably received
in the lens holder along an axis of the lens holder; an image pick-up
module being arranged to receive a light from the lens; and a protective
member attached the lens holder and configured for preventing dust
and/or particle contamination associated with a relative movement
of the lens barrel and the lens holder from falling onto the image
pick-up module.
2. The digital camera module as claimed in claim 1, wherein the
protective member is annular.
3. The digital camera module as claimed in claim 1, wherein the
lens barrel has an external thread defined in an outer periphery
thereof, and the lens holder has an internal thread defined in an
inner periphery thereof, the external thread of the lens barrel
engaging with the internal thread of the lens holder.
4. The digital camera module as claimed in claim 1, wherein the
lens holder has a raised lip projecting from an inner periphery
thereof, the protective member is secured on the raised lip.
5. The digital camera module as claimed in claim 4, wherein the
protective member is annular.
6. The digital camera module as claimed in claim 3, wherein the
protective member is ring-shaped, and has a raised lip projecting
from an outer periphery thereof, an outer periphery of the raised
lip engaging with an inner periphery of the lens holder.
7. The digital camera module as claimed in claim 6, wherein the
protective member is integrally formed with the lens holder.
8. The digital camera module as claimed in claim 2, wherein the
lens barrel has an internal thread defined in an inner periphery
thereof, and the lens holder has an external thread defined in an
outer periphery thereof, the internal thread of the lens barrel
engaging with the external thread of the lens holder.
9. The digital camera module as claimed in claim 8, wherein the
protective member is securely disposed on a top surface of the lens
holder.
10. The digital camera module as claimed in claim 9, wherein the
lens barrel has a first cylinder portion and a second cylinder portion,
a diameter of the second cylinder portion is greater than that of
the first cylinder portion, the internal thread being defined in
the second cylinder portion.
11. The digital camera module as claimed in claim 1, wherein the
image pick-up module comprises a base plate, and an image pick-up
chip secured on the base plate, the lens holder being secured on
the base plate.
12. The digital camera module as claimed in claim 11, wherein the
image pick-up chip has a plurality of chip pads arranged on a top
side thereof, the base plate has a plurality of top pads arranged
on a top surface, and a plurality of bottom pads arranged on a bottom
surface on an opposite side of the base plate to the top surface,
the chip pads of the image pick-up chip electrically connect with
corresponding top pads of the base plate via a plurality of bonding
wires.
13. A digital camera module, comprising: a lens barrel having an
external thread defined in an outer periphery thereof, and at least
one lens received therein; a lens holder having an internal thread
defined in an inner periphery thereof, the external thread engaging
with the internal thread of the lens barrel; a ring member defining
a hole in a center thereof for transmitting light therethrough,
the ring member disposed in the lens holder and adjacent the internal
thread; and an image pick-up module being arranged to receive the
light from the lens.
14. The digital camera module as claimed in claim 13, wherein the
ring member is annular, and the lens holder has a raised lip projecting
from inner periphery thereof, the ring member is secured on the
raised lip.
15. The digital camera module as claimed in claim 14, wherein the
ring member is annular, and has a raised lip projecting from an
outer periphery thereof, the outer periphery of the raised lip tightly
engaging with an inner periphery of the lens holder.
16. A digital camera module, comprising: a lens barrel having an
internal thread defined in an inner periphery thereof, and at least
one lens received therein; a lens holder having an external thread
defined in an outer periphery thereof, the external thread engaging
with the internal thread of the lens holder; a ring member having
a hole in a center thereof for transmitting light therethrough,
the ring member disposed on an en surface of the lens holder and
received in the lens barrel; and an image pick-up module being arranged
to receive light from the lenses.
17. The digital camera module as claimed in claim 16, wherein the
lens barrel has a first cylinder portion and a second cylinder portion,
a diameter of the second cylinder portion is greater than that of
the first cylinder portion, the internal thread defined in the second
cylinder portion.
18. The digital camera module as claimed in claim 16, wherein the
ring member is annular.
Digital Camera Patent Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to digital camera
modules and, more particularly, to a digital camera module which
improves image quality.
[0003] 2. Discussion of the Related Art
[0004] 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 in a mobile phone or PDA in which the digital camera is mounted.
[0005] A digital camera module, as shown in FIG. 3, includes a
lens barrel 10, a lens holder 12, and an image pick-up module 14.
The lens barrel 10 has an external thread 102, and the lens holder
12 has an internal thread 122. The lens barrel 10 is received in
the lens holder 12 via the thread engagement between the external
thread 102 and the internal thread 122. The image pick-up module
14 includes a base plate 142 and an image pick-up chip 144. The
lens holder 12 is fixed on the base plate 142. During auto focusing,
a distance between the lens barrel 10 and the image pick-up chip
144 is slightly adjusted to make the digital camera module focus
by means of adjusting the thread engagement of the internal thread
122 of the lens holder 12 and the external thread 102 of the lens
barrel 10. Lastly, the lens holder 12 is secured on the base plate
142 via adhesive.
[0006] However, dust and/or particle pollution/contamination associated
with friction between the lens barrel 10 and the lens holder 12
may fall onto the image pick-up chip 144, thus affecting image quality
of the digital camera module.
[0007] What is needed, therefore, is a digital camera module which
overcomes the above-described problem.
SUMMARY OF THE INVENTION
[0008] A digital camera module comprises a lens barrel, a lens
holder, an image pick-up module, and a protective member. The lens
barrel is hollow, and has at least one lens received therein. The
lens holder is hollow. The lens barrel is movably received in the
lens holder along an axis of the lens holder. The image pick-up
module is arranged to receive a light from the lenses. The protective
member is configured for preventing dust and/or particles associated
by friction between the lens barrel and the lens holder falling
onto the image pick-up module.
[0009] 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
[0010] Many aspects of the digital camera module can be better
understood with reference to the following drawings. The components
in the drawings are not necessarily drawn to scale, the emphasis
instead being placed upon clearly illustrating the principles of
the present digital camera module. Moreover, in the drawings, like
reference numerals designate corresponding parts throughout the
several views.
[0011] FIG. 1 is an schematic view of a digital camera module,
in accordance with a first preferred embodiment.
[0012] FIG. 2 is an schematic view of a digital camera module,
in accordance with a first preferred embodiment.
[0013] FIG. 3 is an schematic view of a typical digital camera
module.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0014] Referring now to the drawings, FIG. 1 shows a digital camera
module 100 according to a first preferred embodiment. The digital
camera module 100 is adapted for use in a 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. The digital camera module
100 includes a lens barrel 20, a lens holder 22, a ring member 24
as a protective member, and an image pick-up module 26.
[0015] The lens barrel 20 is a hollow cylinder in shape, with two
open ends so that light can be transmitted therethrough. The lens
barrel 20 has a plurality of lenses 202 (only one shown) received
therein. The lens barrel 20 has an external thread 204 defined in
an outer periphery thereof.
[0016] The lens holder 22 is a hollow cylinder with two open ends
allowing light to be transmitted therethrough. The lens holder 22
has a raised lip 222 projecting from middle portion of an inner
periphery thereof. The lens holder 22 has an internal thread 224
defined in an inner periphery thereof, corresponding to the external
thread 204 of the lens barrel 20.
[0017] The ring member 24 is annular in shape, and supported by
the raised lip 222 of the lens holder 22.
[0018] The image pick-up module 26 includes a base plate 27, a
chip means 28, an image pick-up chip 29, and a plurality of bonding
wires 30. The base plate 27 is made of a material such as a plastic,
a ceramic or a fibrous composite. The base plate 27 has a plurality
of top pads 271 on a top surface, a plurality of bottom pads 272
on a bottom surface thereof. The bottom pads 272 are positioned
corresponding to and electrically connecting with the respective
top pads 271. The base plate 27 is used for electrically connecting
the image pick-up chip 29 to other printed circuit boards.
[0019] The image pick-up chip 29 is adhered to the top surface
of the base plate 27 via the adhesive means 28. A top side of the
image pick-up chip 29 is arranged with a photosensitive area 291
and a plurality of chip pads 292 around the photosensitive area
291.
[0020] The bonding wires 30 are made of a conductive material such
as gold or aluminum alloy. One end of each bonding wire 30 is connected/joined
with a respective chip pad 292 of the image pick-up chip 29, and
the other end of the bonding wires 30 is connected/joined with a
respective top pad 271 of the base plate 27.
[0021] In assembling the digital camera module 100, the ring member
24 is received in the lens holder 22 via an open end of the lens
holder 22, and supported by the raised lip 222. Then, the lens barrel
20 is placed in the lens holder 22, with the external thread 204
of the lens barrel 20 engaging with the internal thread 224 of the
lens holder 22. Then, the lens holder 22 is fixed on the image pick-up
module 24, with the image pick-up chip 29 received in the lens holder
22 and the lens holder secured on the base plate 27. During auto
focusing, a distance between the lens barrel 20 and the image pick-up
chip 29 can be adjusted to focus the digital camera module by adjusting
the thread engagement of the external thread 204 of the lens barrel
20 and the internal thread 224 of the lens holder 22.
[0022] In the first embodiment, since a protective member 40 is
disposed between the lens barrel 40 and the top surface of the lens
holder 42, dust and/or particle pollution/contamination associated
with friction between the lens barrel 40 and the lens holder 42
can be effectively prevented from entering the image pick-up module.
In addition, the ring member 24 may be tightly sandwiched between
the lens barrel 20 and the lens holder 22.
[0023] Referring to FIG. 3, another digital camera module 200 according
to a second preferred embodiment is provided. The digital camera
module 200 includes a lens barrel 40, a lens holder 42, a ring member
44 as a protective member, and an image pick-up module 46. The image
pick-up module 46 is similar to the image pick-up module 26 of the
first embodiment, and includes a base plate 47, and an image pick-up
chip 49 disposed on the base plate 47.
[0024] The lens barrel 40 is a hollow cylinder in shape with two
open ends so that light can be transmitted therethrough. The lens
barrel 40 includes a first cylinder portion 402, and a second cylinder
portion 404 integrally formed with the first cylinder portion 402.
An inner diameter of the first cylinder portion 402 is smaller than
that of the second cylinder portion 404. The first cylinder portion
402 has a plurality of lenses 406 (only one shown) received therein.
The second portion 404 has an internal thread 408 defined in an
inner periphery thereof.
[0025] The lens holder 42 is a hollow cylinder with two open ends
so that light can be transmitted therethrough. The lens holder 42
has a projecting stage 422 projecting from outer periphery thereof
adjacent a bottom thereof. The lens holder 42 has an external thread
424 defined in an outer periphery thereof, corresponding to the
internal thread 408 of the lens barrel 40.
[0026] The ring member 44 is ring-shaped, and disposed on a top
surface 426 of the lens holder 42. The ring member 24 is tightly
sandwiched between the lens barrel 40 and the top surface 426 of
the lens holder 42.
[0027] In assembling the digital camera module 200, the protective
member 44 is received in the lens holder 42 via an open end of the
lens holder 42, and disposed on the top surface 426 of the lens
holder 42. The lens barrel 40 is placed around the lens holder 42,
with the internal thread 408 engaging with the external thread 424
of the lens holder 42. Then, the lens holder 42 is fixed on the
image pick-up module 46, with the image pick-up chip 49 of the image
pick-up module 46 received in the lens holder 42 and the lens holder
secured on the base plate 47. During auto focusing, a distance between
the lens barrel 40 and the image pick-up chip 49 is adjusted to
focus the digital camera module by adjusting the thread engagement
of the external thread 408 of the lens barrel 40 and the internal
thread 424 of the lens holder 42.
[0028] In the second embodiment, since a protective member 40 is
disposed between the lens barrel 40 and the top surface of the lens
holder 42, dust and/or particle pollution/contamination in associated
with friction between the lens barrel 40 and the lens holder 42
can be effectively prevented entering the image pick-up module.
In addition, the thread engagement between the lens barrel 40 and
the lens holder 42 disposed on an outer periphery of the lens holder
42 on the image pick-up chip 38 can also prevent particle or dust
from falling onto the image pick-up chip 38, thus improving image
quality of the digital camera module.
[0029] In alternative embodiment, the plate may be a circular washer,
or other member of other shape having a hole in a center thereof
such that a light from the lenses can be transmitted through the
plate to the image pick-up module. An outer diameter of the protective
member may be equal to an inner diameter of the lens holder. The
protective member may be integrally formed with the lens holder.
[0030] 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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