U.S. patent application number 11/872638 was filed with the patent office on 2008-02-14 for endoscopic imaging apparatus and capsule-type endoscope.
This patent application is currently assigned to OLYMPUS CORPORATION. Invention is credited to Noriyuki Fujimori.
Application Number | 20080039694 11/872638 |
Document ID | / |
Family ID | 34799325 |
Filed Date | 2008-02-14 |
United States Patent
Application |
20080039694 |
Kind Code |
A1 |
Fujimori; Noriyuki |
February 14, 2008 |
ENDOSCOPIC IMAGING APPARATUS AND CAPSULE-TYPE ENDOSCOPE
Abstract
An endoscopic imaging includes an image sensor having a
polygonal outline; a lens for focusing an image onto the image
sensor; a lens support member abutting on the image sensor, and
supporting the lens; and an abutting portion formed while extending
from a lower edge portion of the lens support member, the abutting
portion abutting on at least two sides of an outline of the image
sensor to position the lens support member so that the lens is
positioned at a predetermined position of the image sensor.
Inventors: |
Fujimori; Noriyuki; (Nagano,
JP) |
Correspondence
Address: |
SCULLY SCOTT MURPHY & PRESSER, PC
400 GARDEN CITY PLAZA
SUITE 300
GARDEN CITY
NY
11530
US
|
Assignee: |
OLYMPUS CORPORATION
43-2, Hatagaya 2-chome, Shibuya-ku
Tokyo
JP
151-0072
|
Family ID: |
34799325 |
Appl. No.: |
11/872638 |
Filed: |
October 15, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11486950 |
Jul 14, 2006 |
|
|
|
11872638 |
Oct 15, 2007 |
|
|
|
PCT/JP2005/000546 |
Jan 18, 2005 |
|
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|
11486950 |
Jul 14, 2006 |
|
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Current U.S.
Class: |
600/177 |
Current CPC
Class: |
H05K 2201/042 20130101;
H05K 3/4691 20130101; H05K 1/144 20130101; H05K 1/148 20130101;
H05K 2201/10037 20130101; A61B 1/051 20130101; A61B 1/00188
20130101; A61B 1/041 20130101; H05K 1/147 20130101; A61B 1/00096
20130101; A61B 1/00032 20130101 |
Class at
Publication: |
600/177 |
International
Class: |
A61B 1/06 20060101
A61B001/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 19, 2004 |
JP |
2004010712 |
Jan 22, 2004 |
JP |
2004014620 |
Jan 26, 2004 |
JP |
2004017138 |
Claims
1. A capsule endoscope that is configured to obtain an image inside
a subject when the capsule endoscope is putted in the subject, the
capsule endoscope comprising: a sealed container that accommodates
a functional circuit; a front cover that forms a front portion of
the sealed container; a lens unit that focuses light incident
through the front cover; an internal member that at least includes
the lens unit held in the sealed container; and a positioning
portion that aligns a center of entrance pupil of the front cover
and a center of entrance pupil of the lens unit on a same optical
axis.
2. The capsule endoscope according to claim 1, wherein the internal
member is arranged in the front cover, and the positioning portion
engages the front cover with the internal member so that the front
cover and the internal member are relatively rotatable about the
optical axis.
3. The capsule endoscope according to claim 1, wherein the
positioning portion has a projection portion that is projected
toward a direction orthogonal to the optical axis of the front
cover, the projection portion being abutted on a front surface of
the internal member to restrict the optical axis of the lens unit
to be inclined with respect to the optical axis of the front cover,
the projection portion positioning the center of entrance pupil of
the lens unit at the center of entrance pupil of the front
cover.
4. The capsule endoscope according to claim 3, wherein the
projection portion is provided all around an inner circumference of
the front cover.
5. The capsule endoscope according to claim 1, wherein the lens
unit includes a lens member and a cylindrical lens frame that holds
the lens member, and the lens frame has a light-shielding portion
that restricts incident light and that is circumferentially located
on an incident side of the lens member.
6. The capsule endoscope according to claim 1, wherein a region of
the front cover is formed in an even thickness, the region
corresponding to at least an incident range of light passing
through the lens unit.
7. The capsule endoscope according to claim 3, wherein the internal
member includes a wiring board having an outer diameter so that at
least a part of the wiring board is fitted in an inner
circumferential surface of the front cover when the internal member
is arranged in the front cover, the lens unit being held by a
through hole made in a central portion of the wiring board; and a
light-emitting device that is mounted on a surface located on a
front side of the wiring board and illuminates a subject with
illumination light through the front cover.
8. The capsule endoscope according to claim 7, wherein the
projection portion is abutted against the surface of the wiring
board, the light-emitting device being mounted on the surface.
9. The capsule endoscope according to claim 1, wherein the front
cover is formed in a hemispherical and dome shape, and the center
of entrance pupil of the front cover has a center of curvature of
the dorm shape.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 11/486,950 filed Jul. 14, 2006, which is a continuation of PCT
international application Ser. No. PCT/JP2005/000546 filed Jan. 18,
2005 which designates the United States, and which claims the
benefit of priority from Japanese Patent Applications No.
2004-010712, filed Jan. 19, 2004; No. 2004-014620, filed Jan. 22,
2004; and No. 2004-017138, filed Jan. 26, 2004, the entire contents
of each of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an endoscopic imaging
apparatus and a capsule endoscope which obtain an image inside a
subject when the capsule endoscope is putted in the subject.
[0004] 2. Description of the Related Art
[0005] Recently, instead of the conventional endoscope, a
swallowing type endoscope, i.e., a so-called capsule endoscope
receives attention because pain of a subject can be reduced and so
on. For example, as shown in FIG. 21, in the capsule endoscope, a
wiring board 2 and a power source 3 are accommodated in a sealed
container 1 formed in a capsule shape. A functional circuit is
formed on the wiring board. The capsule endoscope is configured to
obtain the image inside the subject as being the test body while
the capsule endoscope is putted in a body cavity of the subject.
The sealed container 1 includes a cylindrical container main body
1a having a bottom and a front cover 1b molded by an optical
material. The sealed container 1 is configured to attach the front
cover 1b to a front portion of the container main body 1a while
water-tightness is secured between the container main body 1a and
the front cover 1b, after the wiring board 2 and the power source 3
are accommodated in the container main body 1a. The sealed
container 1 is formed in a size to an extent in which a human can
swallow the sealed container 1, and both end portions of the sealed
container 1 are formed in a hemispherical shape. In order to form a
circuit of the above-described functions circuit, various
functional components and electronic components such as an
illumination unit 4, a lens unit 5, an imaging device 6, and a
wireless transmission unit 7 are mounted on the wiring board 2.
[0006] In the case of use of the capsule endoscope, the subject can
swallow the capsule endoscope while a power source 3 is turned on.
When the capsule endoscope is putted inside the body cavity of the
subject, while an observation range of the subject such as the
stomach, the small intestine, and the large intestine is
illuminated with illumination light emitted from illumination unit
4 through the front cover 1b until the capsule endoscope is
discharged to the outside of the body, reflected light incident
through the front cover 1b is focused to an imaging device 6
through a lens unit 5, and the reflected light focused to the
imaging device 6 is output as an image signal. Then, the image
signal output from the imaging device 6 is wirelessly transmitted
to the outside by a wireless transmission unit 7, and image
information on the subject can be received and observed by a
receiver placed outside the subject (For example, see JP-A No.
2001-91860 (KOKAI)).
[0007] However, in the capsule endoscope, it is necessary that the
components be correctly positioned among each other in order to
obtain a good image within the subject. Particularly, in an optical
system that focuses the reflected light incident through the front
cover 1b on the imaging device 6, it is necessary to correctly
perform the positioning, because the optical system has a direct
influence on image quality in the subject.
[0008] Therefore, in assembling the capsule endoscope, it is
necessary that the correct positioning be simultaneously performed,
which makes assembling work remarkably complicated and thus taking
a considerable time to assemble the capsule endoscope.
SUMMARY OF THE INVENTION
[0009] An endoscopic imaging apparatus according to one aspect of
the present invention includes an image sensor having a polygonal
outline; a lens for focusing an image onto the image sensor; a lens
support member abutting on the image sensor, and supporting the
lens; and an abutting portion formed while extending from a lower
edge portion of the lens support member, the abutting portion
abutting on at least two sides of an outline of the image sensor to
position the lens support member so that the lens is positioned at
a predetermined position of the image sensor.
[0010] A capsule endoscope according to another aspect of the
present invention includes an illumination board section in which
an illumination unit for emitting illumination light illuminating a
tested region of a subject is arranged; an imaging board section in
which an image sensor imaging the tested region of the subject is
arranged; a flexible wiring board section which is connected to the
illumination board section and the imaging board section, the
flexible wiring board section being made from a flexible material
in which the illumination board section and the imaging board
section are integrally formed; a lens support member which supports
a lens for focusing reflected light of the illumination light from
the tested region and has a cylindrical member whose one end side
is positioned with respect to the image sensor; a hole which is
made while piercing through the illumination board section, has an
inner diameter larger than an outer diameter of the lens support
member in order to fit the lens support member in the hole; and a
supporting unit which positions and supports the illumination board
section with respect to the lens support member when the flexible
wiring board section is folded to insert other end side of the lens
support member into the hole, the supporting unit being provided in
the lens support member.
[0011] A capsule endoscope according to still another aspect of the
present invention is configured to obtain an image inside a subject
when the capsule endoscope is putted in the subject. The capsule
endoscope includes a sealed container which accommodates a
functional circuit; a front cover which is made of an optical
material, is formed in a hemispherical and dome shape whose
proximal end is opened, and forms a front portion of the sealed
container; an internal member which is arranged in the front cover
at the proximal end; a lens unit which is held by the internal
member and focuses light incident through the front cover; and a
positioning unit which is formed between the front cover and the
internal member and alternately aligns a center of entrance pupil
of the front cover with a center of entrance pupil of the lens unit
on a same optical axis by engaging the internal member with the
front cover when the internal member is inserted into the proximal
end of the front cover.
[0012] The above and other objects, features, advantages and
technical and industrial significance of this invention will be
better understood by reading the following detailed description of
presently preferred embodiments of the invention, when considered
in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a sectional side view showing a capsule endoscope
according to an embodiment of the present invention;
[0014] FIG. 2 is a development plan view showing a wiring board
which is of an internal member of the capsule endoscope of FIG.
1;
[0015] FIG. 3 is a sectional side view of FIG. 2;
[0016] FIG. 4 is a bottom view of FIG. 2;
[0017] FIG. 5 is a cross-sectional view taken along line V-V of
FIG. 1;
[0018] FIG. 6 is a cross-sectional view taken along line VI-VI of
FIG. 1;
[0019] FIG. 7 is a cross-sectional view taken along line VII-VII in
FIG. 1;
[0020] FIG. 8 is a cross-sectional view taken along line VIII-VIII
of FIG. 1;
[0021] FIG. 9 is a cross-sectional view taken along line IX-IX of
FIG. 1;
[0022] FIG. 10 is a cross-sectional view taken along line X-X of
FIG. 1;
[0023] FIG. 11 is a cross-sectional view taken along line XI-XI of
FIG. 1;
[0024] FIG. 12 is an enlarged cross-sectional view of the imaging
board section of FIG. 1;
[0025] FIG. 13 is a front view showing CCD and a positioned
holder;
[0026] FIG. 14 is a side view showing CCD and the positioned
holder;
[0027] FIG. 15 is a sectional side view showing CCD and the
positioned holder;
[0028] FIG. 16 is an enlarged cross-sectional view showing main
parts of internal members applied to the capsule endoscope of FIG.
1;
[0029] FIG. 17 is an exploded sectional side view showing a state
where the internal members of the capsule endoscope of FIG. 1 are
accommodated in a sealed container;
[0030] FIG. 18 is a sectional side view showing a front cover
applied to the sealed container of the capsule endoscope of FIG.
1;
[0031] FIG. 19 is a cross-sectional view taken along line XIX-XIX
in FIG. 18;
[0032] FIG. 20 is a conceptual view for explaining an example of
use of the capsule endoscope; and
[0033] FIG. 21 is a sectional side view showing a conventional
capsule endoscope.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Exemplary embodiments of an endoscopic imaging apparatus and
a capsule endoscope according to the invention will be described in
detail with reference to the accompanying drawings. However, the
present invention is not limited to the embodiments.
[0035] FIG. 1 is a sectional side view showing a capsule endoscope
according to an embodiment of the invention. A capsule endoscope C
illustrated in FIG. 1 has a size which can be putted from a mouth
of a subject such as human or animal into its body. The capsule
endoscope C obtains image data which is of internal information on
alimentary canals such as the gaster, the small intestine, and the
large intestine, after the capsule endoscope C is put into the body
until the capsule endoscope C is discharged from the body. The
capsule endoscope C includes an internal power source 10, a
rigid-flexible wiring board 20 provided with a functional circuit
which executes predetermined functions, and a capsule-shaped sealed
container 100 accommodating the internal power source 10 and the
wiring board 20.
[0036] The internal power source 10 accumulates drive power
supplied to the functional circuit. In the embodiment, three
general-purpose silver oxide button cells (hereinafter also simply
referred to as button cell 10) are used as the internal power
source 10. The three button cells 10 are not always required, but
the number of button cells 10 may appropriately be determined
according to a time during which the functional circuit is
operated. The silver oxide cell is not always used. Alternatively a
rechargeable battery, a self-generating battery, and the like may
be used.
[0037] The wiring board 20 is a complex board (hereinafter
sometimes referred to as rigid-flexible wiring board 20 as
appropriate) which includes plural rigid wiring board sections 20R
and a flexible wiring board section 20F sequentially connecting the
plural rigid wiring board section 20R. The rigid wiring board
section 20R is made from a relatively rigid base material such as
glass epoxy resin. Various functional components and electronic
components constituting the functional circuit are mainly mounted
on the rigid wiring board section 20R. The flexible wiring board
section 20F is made from a flexible film base material such as
polyimide resin and polyester resin and serves as mainly a cable
which electrically connects the plural rigid wiring board sections
20R to each other.
[0038] The functional circuit formed on the wiring board 20 has
plural predetermined functional sections necessary to obtain image
data, for example, an illumination function for illuminating a
predetermined imaging range with illumination light, an imaging
function for converting the reflected light by the irradiation of
the illumination light into the image signal, a switch function for
turning on and off supply voltage from the internal power source
10, a voltage conversion function for adjusting an internal power
source voltage to a predetermined constant voltage, a transmission
processing function for modulating and amplifying a given image
signal, an antenna function for externally outputting the modulated
and amplified image signal in the form of the wireless signal, and
a control function for controlling the whole of the functions.
[0039] In the embodiment, the functional sections are divided into
plural pieces of the rigid wiring board section 20R. Specifically,
the rigid wiring board section 20R of the wiring board 20 includes
an illumination board section 20R1 for implementing the
illumination function, an imaging board section 20R2 for
implementing the imaging function and the control function, a
switch board section 20R3 for implementing the switch function, a
power source board section 20R4 for implementing the voltage
conversion function, a transmission board section 20R5 for
implementing the transmission processing function, and an antenna
board section 20R6 for implementing the antenna function.
[0040] As shown in FIGS. 1 to 6, the illumination board section
20R1 is disk-shaped and has an attachment hole 21 in the center
thereof and a straight-line portion 22R1 in a part of a
circumferential surface thereof. The attachment hole 21 and the
straight-line portion 22R1 are references of the electronic
components arranged on the illumination board section 20R1. The
attachment hole 21 is small round, and a lens unit 30 described
later is attached in the attachment hole 21. The straight-line
portion 22R1 is formed by linearly cutting a circumferential
portion of the illumination board section 20R1 and is provided at a
right angle to an extending direction of the flexible wiring board
section 20F.
[0041] A light-emitting device 23 such as a white light diode
(Light Emitting Diode) is mounted on one of mounting surfaces of
the illumination board section 20R1 in order to implement the
illumination function. As shown in FIGS. 4 and 5, the four
light-emitting devices 23 are mounted at equal intervals around the
attachment hole 21 while equally separated away from the attachment
hole 21. The four light-emitting devices 23 are not always
required, but any number of, for example three or less or five or
more of, light-emitting devices 23 may be adopted as long as the
light-emitting devices 23 sufficiently exert the illumination
function. The diode is not always used as the light-emitting
device. Alternatively, EL (electroluminescence) may be used.
[0042] On the other hand, the electronic components constituting a
drive circuit 24 for the light-emitting device 23 are mounted on
the other mounting surface of the illumination board section 20R1.
The electronic components include tall electronic components such
as a driving electronic component for driving the light-emitting
device 23 and an electronic component for stably supplying voltage
to the light-emitting device 23 and low-profile electronic
components such as a small capacitor and a small resistor.
[0043] In the case where the illumination board section 20R1 and
the imaging board section 20R2 are laminated with a desired
interval by folding the flexible wiring board section 20F
connecting the illumination board section 20R1 and the imaging
board section 20R2, the tall electronic components such as the
driving electronic component and the electronic component for
stably supplying the voltage face the low-profile electronic
components such as the small capacitor and the small resistor which
are arranged in a surface (front surface of imaging board section
20R2) oppositely facing the illumination board section 20R1 of the
imaging board section 20R2.
[0044] On the other hand, in the case where the illumination board
section 20R1 and the imaging board section 20R2 are laminated by
folding the flexible wiring board section 20F connecting the
illumination board section 20R1 and the imaging board section 20R2,
the low-profile electronic components such as the small capacitor
and the small resistor face a later-mentioned tall and large
capacitor which is arranged in the surface (front surface of
imaging board section 20R2) oppositely facing the illumination
board section 20R1 of the imaging board section 20R2.
[0045] That is, in the rigid-flexible wiring board 20 in which the
illumination board section 20R1 and the imaging board section 20R2
are arranged by folding the flexible wiring board section 20F
connecting the illumination board section 20R1 and the imaging
board section 20R2, while the tall and large capacitor arranged in
the front surface of the imaging board section 20R2, the
low-profile small capacitor, and the electronic components such as
the capacitor are alternately combined, the tall driving electronic
component, the electronic component for stably supplying the
voltage, the low-profile electronic components such as the small
capacitor and the small resistor are arranged in the back surface
of the illumination board section 20R1.
[0046] Therefore, a distance between the illumination board section
20R1 and the imaging board section 20R2 can be narrower than a sum
of a height of the tall electronic component arranged in the back
surface of the illumination board section 20R1 and the tall
electronic component arranged in the front surface of the imaging
board section 20R2. The flexible wiring board section 20F is formed
to be longer than an assembled length of a later-mentioned image
sensor and the lens unit 30.
[0047] After the illumination board section 20R1 having the above
configuration is arranged while oppositely facing the imaging board
section 20R2 at a predetermined interval, the illumination board
section 20R1 and the imaging board section 20R2 are fixed to each
other while electrically insulated by a adhesive agent having an
insulating property.
[0048] As shown in FIGS. 1 to 4, 7, and 8, the imaging board
section 20R2 is disk-shaped, has a diameter equal to or slightly
smaller than that of the illumination board section 20R1, and has
two straight-line portions 22R2 in the circumferential surface. The
straight-line portions 22R2 are formed by linearly cutting the
circumferential portion of the imaging board section 20R2. The
straight-line portions 22R2 are parallel to each other, and are
provided at a right angle to the extending direction of the
flexible wiring board section 20F. The straight-line portions 22R2,
i.e., the extending direction of the flexible wiring board section
20F becomes a reference of the electronic components arranged on
the imaging board section 20R2.
[0049] An image sensor provided as a ball grid array package is
mounted on one mounted surface (front surface) of the imaging board
section 20R2 such that the extending direction of the flexible
wiring board section 20F coincides with a direction of pixel array.
In the image sensor, a pixel surface of a rectangular solid-state
imaging device such as CCD (Charge Coupled Diode) or CMOS
(Complementary Metal Oxide Semiconductor) is coated with a cover
glass 28. An outline of the cover glass 28 is formed in a polygonal
shape. (Hereinafter, the solid-state imaging device is simply
referred to as CCD 26.)
[0050] As shown in FIGS. 1 and 12 to 16, a holder 29 (lens support
member) is attached to the cover glass 28, and a lens unit 30 is
placed in the holder 29.
[0051] The holder 29 includes a cylindrical portion 29a which has a
diameter larger than that of the pixel surface of the CCD 26, and a
base 29b which is integrally formed with a proximal end portion of
the cylindrical portion 29a. A hole portion made in the cylindrical
portion 29a pierces through the base 29b to guide the light
incident from the holder 29 onto the CCD 26. A lower surface of the
base 29b, i.e., the outline of the surface abutting on an upper
surface of the CCD 26 has a substantially square shape whose side
is substantially equal to a short side of the cover glass 28.
Abutting portions 29c extend downward from the two adjacent sides
of the lower edge portion and abut on the side surfaces of the
cover glass 28.
[0052] As shown in FIGS. 13 to 15, in the holder 29, while the
lower surface of the base 29b abuts on the upper surface of the
cover glass 28, the base 29b abuts on the side surfaces which are
of the two adjacent sides of the upper surface of the cover glass
28. Therefore, the holder 29 is accurately attached to the cover
glass 28 through the base 29b while an axial center of the
cylindrical portion 29a is aligned with the central axis (optical
axis) L of a visual field in the CCD 26.
[0053] A reinforcement portion 29d having substantially the same
shape as the abutting portion 29c extends from the lower edge
portion of the holder 29, and the cover glass 28 and the holder 29
are fixed to each other by a black-colored adhesive agent after the
attachment. As shown in FIG. 12, since a black-colored adhesive
agent 29e is applied to an exposed surface where the cover glass 28
is not covered with the holder 29, the incidence of the light from
the exposed surface can be prevented to project the clear image
onto CCD 26.
[0054] The lens unit 30 includes a cylindrical lens frame 31 and a
pair of lens members 32 and 33. A cylindrical slide portion 31a
that has a relatively large outer diameter fitted in the
cylindrical portion 29a of the holder 29, a cylindrical attachment
portion 31b that is continuously provided to a front portion of the
slide portion 31a while coaxially aligned with the slide portion
31a and has a relatively small diameter fitted in the attachment
hole 21 of the illumination board section 20R1, and a
light-shielding portion 31c which is projected inward from all the
circumferences of the front portion of the attachment portion 31b
are integrally formed in the lens frame 31. An outer
circumferential surface of the lens frame 31 has a step portion 31d
between the slide portion 31a and the attachment portion 31b. The
front portion of the lens frame 31 is one which takes in the
incident light focusing the image onto the CCD 26, and the
light-shielding portion 31c is one which corresponds to an entrance
pupil for defining an observation range of the image data with
respect to the lens unit 30. An outer end surface of the
light-shielding portion 31c is recessed in a funnel shape while
tapered toward the central axis. A small-diameter portion and a
large-diameter portion are formed in an inner circumferential
surface of the lens frame 31, and a boundary portion between the
small-diameter portion and the large-diameter portion are defined
by a step portion. A small-diameter lens 32 is fitted in the
small-diameter portion. In the small-diameter lens 32 having a
large refractive index, the upper surface is formed flat, and the
lower surface is formed in a convex surface. A flat surface portion
of the small-diameter lens 32 abuts on the light-shielding portion
31c, and the circumferential surface portion of the small-diameter
lens 32 is fitted in the small-diameter portion. A cylindrical
spacer 34, and a large-diameter lens 33 which has a small
refractive index and has a convex upper surface and a flat rear
surface are fitted in the large-diameter portion. The spacer 34
separates the small-diameter lens 32 from the large-diameter lens
33 at a predetermined interval, and attaches the small-diameter
lens 32 and the large-diameter lens 33 to the inside of the lens
frame 31 while optical axes of the small-diameter lens 32 and the
large-diameter lens 33 are aligned with each other. The lens unit
30 is slidably arranged in the cylindrical portion 29a of the
holder 29 through the slide portion 31a while the light-shielding
portion 31c is orientated outward, so that focus can be adjusted by
appropriately changing a position in an optical axis direction with
respect to the pixel surface of the CCD 26.
[0055] Electronic components constituting a drive circuit 27 for
the CCD 26 are mounted on one surface of the imaging board section
20R2. Specifically, large capacitors for a power source voltage
circuit for driving the CCD 26 are arranged next to the CCD 26
based on the arrangement of the CCD 26; small electronic components
such as capacitors and resistors necessary to drive the CCD 26 are
orderly arranged away from the CCD 26 and the large capacitors.
[0056] On the other hand, in the other surface (back surface) of
the imaging board section 20R2, a processor device (hereinafter
simply referred to as DSP 25) such as a DSP (Digital Signal
Processor) for implementing the control function is mounted by flip
chip bonding, and the electronic components such as capacitors are
orderly arranged based on the arrangement of the DSP 25. This
arrangement allows the electronic components to be integrated,
contributing to the downsizing of the capsule endoscope. The DSP 25
performs not only the control function but also the drive control
of CCD signal processing and illumination board section.
[0057] As shown in FIG. 8, in the imaging board section 20R2,
plural pad portions 35 which is of external terminals are provided
in a region which is located out of the mounting areas of the
electronic components in the other mounting surface. The pad
portion 35 is an electrically conductive portion which is roundly
exposed in the mounting surface of the imaging board section 20R2.
The pad portion 35 includes a portion which functions as an
external power supply terminal for directly supplying the electric
power from an external power source (not shown) to the functional
circuit and a portion which functions as an external input terminal
for inputting an initial setting value of the functional circuit to
a memory described later.
[0058] As shown in FIGS. 1 to 4 and 9, the switch board section
20R3 is disk-shaped and has a diameter equal to or slightly smaller
than that of the imaging board section 20R2. Similarly to the
imaging board section 20R2, the switch board section 20R3 has
straight-line portions 22R3 at two points in the circumferential
surface and has a relief hole 36 in a central portion thereof. The
straight-line portions 22R3 are formed by linearly cutting the
circumferential portion of the switch board section 20R3 and are
provided in parallel with each other and at a right angle to the
extending direction of the flexible wiring board section 20F. The
straight-line portions 22R3, i.e., the extending direction of the
flexible wiring board section 20F becomes a reference of the
electronic components arranged on the switch board section 20R3.
The relief hole 36 is used for accommodating a part of a
later-mentioned reed switch 37 and is formed in a long hole shape
extending along the straight-line portion 22R3.
[0059] The reed switch 37 for implementing the switch function is
mounted in the switch board section 20R3 while a part of the reed
switch 37 is accommodated in the relief hole 36 from one mounting
surface side. Therefore, a projection height of the reed switch 37
can be suppressed on the front surface side. In one of mounting
surfaces, the electronic components such as a memory 38, an
oscillator, and a MIX are orderly arranged in the region around the
relief hole 36.
[0060] The reed switch 37, responding to a magnetic field, is a
latch-type switch which turns on and off the electric supply power
from the internal power source 10. In the embodiment, the electric
power supply from the internal power source 10 is turned off in the
case where the magnetic field acts on the reed switch 37 by
bringing a permanent magnet close to the reed switch 37; the
electric power supply from the internal power source 10 is
continuously turned on in the case where the magnetic field does
not act on the reed switch 37.
[0061] The memory 38 is a volatile storage unit in which data such
as the initial setting value of the DSP 25 necessary to drive the
functional circuit is stored. Examples of the initial setting value
of the DSP 25 include a white balance coefficient of the CCD 26,
data for correcting failure caused by a variation in the CCD 26,
and pixel defect address data of the CCD 26. The oscillator
supplies a basic clock to the DSP 25. The MIX is mounted by flip
chip bonding and has a function for mixing the two signals into one
signal when two signals of an image signal output from the DSP 25
and a clock signal are transmitted. As shown in FIG. 1, a positive
electrode contact member 39, which is a contact to a positive
electrode of the button cell 10, formed in a disk spring is
provided in the other mounting surface of the switch board section
20R3.
[0062] As shown in FIGS. 1 to 4 and 10, the power source board
section 20R4 has a diameter smaller than that of the switch board
section 20R3 as well as of a negative electrode of the button cell
10 is disk-shaped. Similarly to the switch board section 20R3, the
power source board section 20R4 has a diameter smaller than that of
the straight-line portions 22R4 at two points in the
circumferential surface. The straight-line portions 22R4 are formed
by linearly cutting the circumferential portion of the power source
board section 20R4 and are provided in parallel with each other and
at a right angle to the extending direction of the flexible wiring
board section 20F. The straight-line portions 22R4, i.e., the
extending direction of the flexible wiring board section 20F
becomes a reference of the electronic components arranged on the
power source board section 20R4.
[0063] In one of mounting surfaces of the power source board
section 20R4, for example, the plural electronic components are
mounted to form a DC-DC converter 40 in order to implement the
voltage conversion function. The DC-DC converter 40 controls the
voltage supplied from the battery in order to obtain the constant
voltage necessary for the capsule endoscope. A negative electrode
contact member (not shown), which is a contact to the negative
electrode of the button cell 10, is provided in the other mounting
surface of the power source board section 20R4.
[0064] As shown in FIGS. 1, 2, 4, and 11, the transmission board
section 20R5 is disk-shaped and has a diameter equal to or slightly
smaller than that of the switch board section 20R3. The
transmission board section 20R5 is produced independently of the
rigid-flexible wiring board 20, and one of mounting surfaces (front
surface) of the transmission board section 20R5 and the flexible
wiring board section 20F are connected by a through-hole land 41.
Similarly to the illumination board section 20R1, the transmission
board section 20R5 has a straight-line portion 22R5 in a part of
the circumferential surface. The straight-line portion 22R5 is
formed by linearly cutting the circumferential portion of the
transmission board section 20R5. The straight-line portion 22R5
becomes a reference of the electronic components arranged on the
transmission board section 20R5.
[0065] In the other mounting surface of the transmission board
section 20R5, for example, the plural electronic components are
mounted to form an RF (Radio Frequency) unit 42 in order to realize
the transmission processing function.
[0066] As shown in FIGS. 1 and 11, the antenna board section 20R6
is disk-shaped, has a diameter smaller than that of the
transmission board section 20R5, and is attached on the other
mounting surface side of the transmission board section 20R5 in
parallel with the antenna board section 20R6. An antenna 43 is
formed in the antenna board section 20R6 by placing a lead wire in
a spiral shape. Both end portions (not shown) of the lead wire,
which constitutes the antenna 43, are electrically connected to
circuit portions of the transmission board section 20R5
respectively. Accordingly, the RE unit 42 can take out the signal
having constant frequency, amplitude, and waveform from the signals
to which the mixing is performed in the switch board section 20R3,
and transmit the signal to the outside from the antenna board
section 20R6.
[0067] As shown in FIGS. 2 to 4, the rigid wiring board sections
20R are previously formed by sequentially connecting the
illumination board section 20R1, the imaging board section 20R2,
the switch board section 20R3, the power source board section 20R4,
and the transmission board section 20R5 in a straight line using
the flexible wiring board section 20F. The illumination board
section 20R1 to the power source board section 20R4 are integrally
formed in a plate shape together with the flexible wiring board
section 20F. After the electronic components are mounted on each of
the illumination board section 20R1 to the power source board
section 20R4, the linear rigid-flexible wiring board 20 is formed
by connecting the transmission board section 20R5 integrated with
the antenna board section 20R6 to the end portion of the flexible
wiring board section 20F.
[0068] The electronic components can easily be mounted by an
ordinary mounting technology to the rigid wiring board section 20R
including the illumination board section 20R1 to the power source
board section 20R4 which are integrally formed in the plate shape
with the flexible wiring board section 20F. In a production stage
at which the rigid wiring board section 20R and the flexible wiring
board section 20F are integrally formed, the electrical connection
is already established between the rigid wiring board section 20R
and the flexible wiring board section 20F, so that shortening of
the production process and facilitation of the assembling work can
be achieved without the connection step.
[0069] The flexible wiring board sections 20F arranged between the
rigid wiring board sections 20R have the different widths and
lengths if needed. The relatively wide flexible wiring board
section 20F arranged between the switch board section 20R3 and the
power source board section 20R4 is divided into two pieces by a
slit 20FS formed along the lengthwise direction.
[0070] First an operation confirming inspection of the functional
circuit is performed to the linearly formed rigid-flexible wiring
board 20. Then, as shown in FIG. 1, the flexible wiring board
section 20F is appropriately folded while the adjacent rigid wiring
board sections 20R oppositely face to each other, and the button
cell 10 is sandwiched and held between the positive electrode
contact member 39 of the switch board section 20R3 and the negative
electrode contact member (not shown) of the power source board
section 20R4 while the electrodes are fitted to the proper
orientation, which allows the rigid-flexible wiring board 20 to be
formed in a cylindrical block of an internal member which can be
accommodated in the sealed container 100.
[0071] The operation confirming inspection is one which confirms
whether the functional circuit is normally operated in the case
where the electric power is supplied to the functional circuit. In
the case of the rigid-flexible wiring board 20 having the above
configuration, the operation confirming inspection of the
functional circuit can be performed while the rigid-flexible wiring
board 20 is formed in the straight line as shown in FIGS. 2 to 4.
That is, in the rigid-flexible wiring board 20 in which the pad
portion 35 is provided in the imaging board section 20R2, for
example, the electric power can be supplied to the functional
circuit by bringing a needle electrode of the external power source
into contact with the pad portion 35 functioning as the external
electric power terminal. Accordingly, even before the button cell
10, which is of the internal power source, is held between the
positive electrode contact member 39 and the negative electrode
contact member (not shown) like a production line of the
rigid-flexible wiring board 20 and the like, the operation
confirming inspection of the functional circuit can be performed to
guarantee the secure operation.
[0072] When the operation confirming inspection is performed using
the external power source, the button cell 10 which is of the
internal power source is never consumed. Therefore, in the case
where the relatively small button cell 10 is used, an operating
time of the functional circuit can sufficiently be secured by the
button cell 10. Further, if needed, not only can an initializing
process be performed, but also the electric power is supplied from
the external power source, such that the initial setting value of
the functional circuit is input to the memory 38 of the switch
board section 20R3 through the pad portion 35 which functions as
the external input terminal.
[0073] In the case where the flexible wiring board section 20F is
folded after the operation confirming inspection, as shown in FIGS.
1 and 16, the other mounting surface (back surface) of the
illumination board section 20R1 and the other mounting surface
(front surface) of the imaging board section 20R2 are caused to
oppositely face to each other, the attachment portion 31b of the
lens unit 30 is fitted in the attachment hole 21 of the
illumination board section 20R1, and the rigid-flexible wiring
board 20 is inserted until the shoulder portion 31d formed between
the slide portion 31a and attachment portion of the lens frame 31
abuts on the other mounting surface of the illumination board
section 20R1. The lens unit 30 fitted in the attachment hole 21 of
the illumination board section 20R1 is positioned and held by the
illumination board section 20R1, in the state where the step
portion 31d formed between the slide portion 31a and attachment
portion 31b of the lens frame 31 abuts on the other mounting
surface of the illumination board section 20R1 while optical axes
of the lens members 32 and 33 and the central axis of the visual
field of the CCD 26 are aligned with the axial center of the
illumination board section 20R1. Even in the state, when the
cylindrical portion 29a of the holder 29 is slid with respect to
the slide portion 31a of the lens frame 31, the distances of the
imaging board section 20R2 and the CCD 26 are changed with respect
to the lens members 32 and 33, which allows the focus of the CCD 26
to be adjusted. After the focus of the CCD 26 is adjusted, a gap
between the illumination board section 20R1 and the imaging board
section 20R2 is filled with an insulating sealing resin P, and the
insulating sealing resin P is cured to hold the bonded state
between the illumination board section 20R1 and the imaging board
section 20R2.
[0074] At this point, after the CCD 26 and the holder 29 are
assembled, the height to the step portion 31d from the front
surface of the imaging board section 20R2, which is of the assembly
height of the CCD 26 and the holder 29, is previously defined to be
higher than the heights of various electronic components arranged
in the front surface of the imaging board section 20R2.
[0075] The flexible wiring board section 20F is folded such that
one of mounting surfaces of the imaging board section 20R2
oppositely faces one of mounting surfaces of the switch board
section 20R3 while the other mounting surface of the switch board
section 20R3 oppositely faces the other mounting surface of the
power source board section 20R4. Therefore, the button cell 10 is
sandwiched and held between the positive electrode contact member
39 and the negative electrode contact member (not shown).
[0076] After the button cell 10 is sandwiched and held between the
switch board section 20R3 and the power source board section 20R4,
a heat-shrinkable tube 44 is attached while surrounding the button
cell 10, the switch board section 20R3, and the power source board
section 20R4. Then, the button cell 10, the switch board section
20R3, and the power source board section 20R4 are pressure-bonded
and held by properly heating the heat-shrinkable tube 44. Then, the
gap between the imaging board section 20R2 and the switch board
section 20R3 and the gap between the power source board section
20R4 and the transmission board section 20R5 are filled with the
insulating sealing resin P and hardened, and the coupled state is
held between the rigid wiring board sections 20R.
[0077] In the case where the cylindrical internal members are
formed in the above manner, in the rigid-flexible wiring board 20,
the flexible wiring board section 20F extends at a right angle from
each straight-line portion 22R with respect to each disk-shaped
rigid wiring board section 20R, so that each flexible wiring board
section 20F can be folded easily and securely along each
straight-line portion 22R from the region close to the rigid wiring
board section 20R. Since the individual straight-line portion 22R
is formed by cutting the disk-shaped rigid wiring board section
20R, for example, the folded flexible wiring board section 20F can
be accommodated in the cut portion as shown in FIGS. 5 and 6. The
flexible wiring board section 20F located in the outer
circumferential portion of the button cell 10 is formed while
divided into two pieces along the lengthwise direction by the slit
20FS, so that the flexible wiring board section 20F is brought into
close contact with the button cell 10 while suiting the
circumferential surface of the button cell 10. As a result, the
large increase in outer-diameter size of each rigid wiring board
section 20R or button cell 10 due to the flexible wiring board
section 20F can be prevented.
[0078] On the other hand, the sealed container 100 which
accommodates the button cell 10 and the rigid-flexible wiring board
20 is divided into a container main body 110 and a front cover
120.
[0079] As shown in FIGS. 1 and 17, the container main body 110
includes a hemispherical and dome-shaped bottom portion 111 and a
substantially cylindrical barrel portion 112. The barrel portion
112 extends continuously to the bottom portion 111. The bottom
portion 111 and the barrel portion 112 are integrally molded by a
synthetic resin material. For example, a cycloolefin polymer,
polycarbonate, acryl, polysulfone, and urethane can be used as the
synthetic resin material for molding the container main body 110.
Particularly, polysulfone is preferably used in consideration of
strength of the container main body 110.
[0080] The barrel portion 112 of the container main body 110 is
tapered (not clearly shown in the drawings), and the diameter of
the barrel portion 112 is slightly increased toward an opening side
of the front. As shown in FIG. 1, not only is the size of the
container main body 110 configured so that the rigid-flexible
wiring board 20 and the button cell 10 can be accommodated, but
also a gap with the accommodated internal members becomes the
minimum, when the rigid-flexible wiring board 20 and the button
cell 10 which are formed in a block as the internal member is
inserted from the side of the antenna board section 20R6.
[0081] In the barrel portion 112 of the container main body 110, an
engagement groove 113 is formed over the entire circumferences of
the inner circumferential surface which is slightly shifted to the
proximal end side of the opening of the front.
[0082] As shown in FIGS. 1, 18, and 19, the front surface side of
the illumination board section 20R1 is covered with the front cover
120, and the front cover 120 includes a hemispherical and
dome-shaped dome portion 121 and an engagement portion 122 that
extends from the proximal end portion of the dome portion 121. The
dome portion 121 and the engagement portion 122 are integrally
molded by a synthetic resin material which becomes an optical
material. Accordingly, the front cover 120 has transparency or
translucency and transmits the image illuminated with the
illumination light to the inside while transmitting the
illumination light from the light-emitting device 23 to the
outside. For example, a cycloolefin polymer, polycarbonate, acryl,
polysulfone, and urethane can be used as the synthetic resin
material for molding the front cover 120. Particularly, the
cycloolefin polymer or polycarbonate is preferably used in
consideration of optical performance and strength of the front
cover 120.
[0083] In the front cover 120, the dome portion 121 has
substantially the same outer-diameter as the front outer diameter
of the barrel portion 112 in the container main body 110, and the
engagement portion 122 has the outer diameter which can be fitted
in the front inner circumference of the barrel portion 112 in the
container main body 110. In the case where the front cover 120 is
attached to the front portion of the container main body 110, the
outer surface of the dome portion 121 can be fitted in the inner
circumference of the front portion of the barrel portion 112
through the engagement portion 122 while being continuous to the
outer surface of the barrel portion 112.
[0084] In the engagement portion 122 of the front cover 120, an
engagement protrusion 123 is provided over the entire
circumferences of the engagement portion 122 at the region
corresponding to the engagement groove 113 of the container main
body 110. The engagement protrusion 123 engages the engagement
groove 113 of the container main body 110 to prevent unexpected
drop-off of the front cover 120 from the container main body 110,
in the case where the front cover 120 is attached to the front
portion of the barrel portion 112. The inner circumferential
diameter of the engagement portion 122 is formed so that the
illumination board section 20R1 of the rigid-flexible wiring board
20 can be fitted in the inner circumference of the engagement
portion 122.
[0085] In the front cover 120, a translucent portion 121a is set in
a range (area surrounded by alternate long and two short dash lines
in FIG. 1) which becomes a predetermined symmetrical area from a
center of curvature of the dome portion 121, and a pupil portion
121b is provided over the entire circumferences of the region
located on the outer circumferential surface of the translucent
portion 121a.
[0086] The translucent portion 121a and the pupil portion 121b
define the observation range of the image data with respect to the
front cover 120. The translucent portion 121a of the front cover
120 is homogenously formed while having the even thickness. On the
other hand, the pupil portion 121b is molded to have a thickness
larger than that of the translucent portion 121a, and the pupil
portion 121b constitutes a projection portion 124 which is
projected inward from the inner circumferential surface of the
engagement portion 122. In the projection portion 124, an abutting
surface 125 located on the proximal end side extends in the
direction orthogonal to the axial center of the front cover 120. In
the case where the abutting surface 125 engagedly abuts on one of
mounting surfaces of the illumination board section 20R1, the
projection unit 124 is configured so that the optical axis of the
lens unit 30 is aligned with the axial center of the front cover
120 while the center of the entrance pupil on the optical axis with
respect to the lens unit 30 is aligned with the center of curvature
(center of the entrance pupil in the front cover 120) of the front
cover 120. In the projection portion 124, the inner diameter is set
to be larger than the mounting area of the light-emitting device 23
in the illumination board section 20R1. In this configuration, in
the case where the illumination board section 20R1 is rotated about
the axial center, the projection portion 124 never interferes with
the light-emitting device 23.
[0087] In the case where the sealed container 100 having the above
configuration accommodates the rigid-flexible wiring board 20 and
button cell 10 which are formed in the block, as shown in FIG. 17,
after the illumination board section 20R1 is previously covered
with the front cover 120, the insulating sealing resin P is applied
to the circumferences of the rigid-flexible wiring board 20 and
button cell 10 while the adhesive agent is applied to the inner
circumferential surface of the container main body 110, and the
internal member is inserted into the container main body 110 to
engage the engagement protrusion 123 of the front cover 120 in the
engagement groove 113 of the container main body 110. Therefore,
the gap between the inner circumferential surface of the container
main body 110 and the outer circumferential surfaces of the rigid
and the gap between flexible wiring board 20 and button cell 10 are
filled with the sealing resin P, and the adhesive agent intrudes
between the engagement portion 122 of the front cover 120 and the
inner circumferential surface of the container main body 110. In
the state where the engagement protrusion 123 of the front cover
120 is engaged in the engagement groove 113 of the container main
body 110, the adhesive agent located between the engagement
protrusion 123 and the engagement groove 113 preferably spreads
through the circumferential direction by relatively rotating the
engagement protrusion 123 and the engagement groove 113.
[0088] In this case, as described above, when one of mounting
surfaces of the illumination board section 20R1 is made only to
abut on the abutting surface 125 of the front cover 120, the
optical axis of the lens unit 30 is aligned with the axial center
of the front cover 120 without inclining the optical axis of the
lens unit 30 while the center of the entrance pupil with respect to
the lens unit 30 is aligned with the center of curvature of the
front cover 120. Additionally, in the case where the illumination
board section 20R1 is inserted into the engagement portion 122,
since the projection portion 124 of the front cover 120 never
interferes with the light-emitting device 23 of the illumination
board section 20R1, it is not necessary to consider an attitude
about the axial centers of the projection portion 124 and
light-emitting device 23. Accordingly, in the assembly, it is not
necessary to adjust the position of the optical system with respect
to the incident light, so that the assembling work can
significantly easily be performed.
[0089] The adhesive agent intruding between the inner
circumferential surface of the container main body 110 and the
outer circumferential surface of the engagement portion 122 in the
front cover 120 secures the desired watertightness between the
inner circumferential surface of the container main body 110 and
the outer circumferential surface of the engagement portion 122,
and there is no anxiety that a liquid such as a body fluid intrudes
in the sealed container 100 in the case where the capsule endoscope
C is putted into the body. Particularly, since the engagement
protrusion 123 and the engagement groove 113 are engaged each other
between the front cover 120 and the front portion of the container
main body 110, the adhesive agent is never peeled off between the
front cover 120 and the front portion of the container main body
110 even if the capsule endoscope C experiences a post-treatment
process such as sterilizing process which is performed after the
assembly, and there is no anxiety that the internal member is
heated or short-circuited by the intrusion of the body fluid
[0090] FIG. 20 is a conceptual view for explaining an example of
the use of the capsule endoscope C. The operation of the capsule
endoscope C will briefly be described with reference to FIG.
20.
[0091] The capsule endoscope C of the embodiment is taken out from
a package 200 into which the permanent magnet (not shown) is
incorporated, the reed switch 37 is started to continuously turn on
the electric power supply with respect to the functional circuit
through the DC-DC converter 40 from the button cell 10 which is of
the internal power source.
[0092] In this state of things, when the subject wearing a jacket
201 swallows the capsule endoscope C, each unit of the functional
circuit can be driven to obtain the image data of the subject by an
instruction from the DSP 25 until the capsule endoscope C is
discharged to the outside of the body. More specifically, the
observation range of the subject such as gaster, small intestine,
and the large intestine is illuminated with the illumination light
emitted from the translucent portion 121a through the translucent
portion 121a of the front cover 120, the reflected light incident
through the translucent portion 121a of the front cover 120 is
focused to the CCD 26 through the lens unit 30, and the reflected
light focused to the CCD 26 is output as the image signal.
[0093] The image signal output from the CCD 26 is modulated and
amplified by the RF unit 42, the image signal is wirelessly
transmitted to the outside through the antenna 43, and the image
data is sequentially stored in an external storage device 203 such
as a CompactFlash.RTM. memory in a receiver 202 attached to the
jacket 201 in the form of the image data. For example, the image
data stored in the external storage device 203 is visualized on a
display 205 through a computer 204, and the image data becomes a
target of a diagnosis by a doctor or a nurse.
[0094] During the operations, in the capsule endoscope C, not only
is the optical axis of the lens unit 30 aligned with the axial
center of the front cover 120, but also the center of the entrance
pupil with respect to the lens unit 30 is aligned with the center
of curvature of the front cover 120. Therefore, all the incident
light beams incident from the translucent portion 121a provided in
the dome unit 121 of the front cover 120 are focused onto the pixel
surface of the CCD 26 by the lens members 32 and 33 of the lens
unit 30, and the significantly favorable image data can be obtained
because the homogeneous translucent portion 121a is formed in the
even thickness.
[0095] The positioning of the optical system with respect to the
incident light is correctly performed without any adjustment work
by causing one of mounting surfaces of the illumination board
section 20R1 to abut on the abutting surface 125 of the front cover
120. Therefore, there is no anxiety that the assembling work
becomes complicated.
[0096] Since the light-shielding portion 31c is provided in the
lens frame 31 which holds the lens members 32 and 33, in the dome
portion 121 of the front cover 120, the incident light passing
through the pupil portion 121b located on the outer circumference
side of the translucent portion 121a can securely be blocked to
effectively prevent the generation of flare in the image data.
[0097] In the capsule endoscope C, the abutting portion 29c is
brought into close contact with the cover glass 28, extends from
the lower edge portion of the holder 29 which holds the lens frame
31 supporting the lens members 32 and 33 focusing the image to CCD
26, and abuts on the outline of the cover glass 28. Therefore, the
lens frame 31 is positioned at a predetermined position with
respect to the CCD 26, so that the lens frame 31 can easily be
positioned for a short period of time at a predetermined position
with respect to a light acceptance surface of the CCD 26.
[0098] The exposed surface of the cover glass 28 is shielded by the
black-colored adhesive agent while the holder 29 is fixed to the
cover glass 28 with the black-colored adhesive agent, so that the
assembling work can be performed with the simple configuration, and
the clear image can be obtained in the CCD 26.
[0099] It is not necessary that the illumination board section 20R1
and the imaging board section 20R2 be separately connected by the
lead wire or the like, and can simply be assembled as compared with
the conventional art.
[0100] In the embodiment, since the illumination board section 20R1
and the abutting surface 125 of the projection portion 124 provided
in the front cover 120 abut on each other while being relatively
rotatable, it is not necessary to consider the attitude about the
axial centers of the illumination board section 20R1 and the
abutting surface 125, and the assembling work can be easily
performed. However, it is not always necessary that the
illumination board section 20R1 and the abutting surface 125 of the
front cover 120 abut on each other while being relatively
rotatable. It is not always necessary that the projection portion
124 of the front cover 120 be formed over the entire
circumferences, but it is sufficient to cause the projection unit
124 to abut on one of mounting surface of the illumination board
section 20R1 at least three points.
[0101] In the rigid-flexible wiring board 20, the illumination
board section 20R1, the imaging board section 20R2, the switch
board section 20R3, and the power source board section 20R4 are
sequentially formed in this order in the straight line by the
flexible wiring board section 20F. However, the illumination board
section 20R1, the imaging board section 20R2, the switch board
section 20R3, and the power source board section 20R4 may
sequentially be located when the flexible wiring board section 20F
is folded. For example, when the illumination board section 20R1,
the imaging board section 20R2, the switch board section 20R3, and
the power source board section 20R4 are located in the same plane,
the illumination board section 20R1, the imaging board section
20R2, the switch board section 20R3, and the power source board
section 20R4 may not always be formed in the straight line.
[0102] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *