JP2005204924A - Capsule type endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide excellent images inside a testee body without complicating assembly work. <P>SOLUTION: A capsule type endoscope C for acquiring the images inside the testee body by the drive of a functional circuit housed inside an airtight container 100 in the case of being fed inside the testee body comprises: a tip cover 120 molded in a roughly hemispherical dome shape opened on a base end side by an optical material for constituting the tip part of the airtight container 100; an illumination substrate part 20R1 arranged inside the base end side of the tip cover 120; a lens unit 30 held by the illumination substrate part 20R1 for image-forming light made incident through the tip cover 120; and a projection part 124 projected inwards from the inner peripheral surface of the tip cover 120 for matching a curvature center which is the pupil center of the tip cover 120 and the pupil center of the lens unit 30 with each other on the same optical axis in the case of abutting the illumination substrate part 20R1 on an abutting surface 125 so as to be engaged therewith. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a capsule endoscope configured to acquire an image inside a subject by driving a functional circuit housed in the inside of the sealed container when it is inserted into the subject.

  In recent years, a swallowable so-called capsule endoscope has attracted attention as a substitute for a conventional endoscope for reasons such as reducing pain of a subject. For example, as shown in FIG. 17, this capsule endoscope accommodates a wiring board 2 and a power source 3 constituting a functional circuit inside a sealed container 1 formed in a capsule shape, and a body cavity of a subject as a subject. An internal image is acquired in a state in which it is inserted. The sealed container 1 includes a container body 1a having a bottomed cylindrical shape and a tip cover 1b formed of an optical material. After the wiring board 2 and the power source 3 are accommodated in the container body 1a, the sealed container 1 is mutually connected. The tip cover 1b is attached to the tip of the container main body 1a while ensuring the desired water tightness. The hermetic container 1 is large enough to be swallowed by humans, and both end portions are each formed in a hemispherical shape. Various functional parts and electronic parts such as the illumination means 4, the lens unit 5, the image sensor 6, and the wireless transmission means 7 are mounted on the wiring board 2 in order to constitute the above-described functional circuit.

  When using this capsule endoscope, the subject may swallow the power supply 3 in the on state. When the capsule endoscope is inserted into the body cavity of the subject, the irradiation light from the illuminating means 4 passes through the distal end cover 1b to the observation range of the subject, for example, stomach, small intestine, large intestine, etc. until it is excreted from the body. On the other hand, the reflected light incident through the tip cover 1b is imaged on the image sensor 6 through the lens unit 5, and the reflected light imaged on the image sensor 6 is output as an image signal. Furthermore, the image signal output from the image sensor 6 is wirelessly transmitted to the outside by the wireless transmission means 7, and information on the in-subject image can be received and observed by a receiver installed outside the subject's body (for example, Patent Document 1).

JP 2001-91860 A

  In order to obtain a good in-subject image in the capsule endoscope as described above, accurate positioning of the components is necessary. In particular, in an optical system for forming an image of reflected light incident through the tip cover 1b on the image sensor 6, it is a part that directly affects the quality of the in-subject image, and thus more accurate positioning is required. It becomes.

  For this reason, when assembling the capsule endoscope, accurate position adjustment must be performed at the same time, and the assembling work becomes extremely complicated and a long working time is required.

  In view of the above circumstances, an object of the present invention is to provide a capsule endoscope that can obtain a good in-vivo image without causing complication of assembly work.

  In order to achieve the above object, a capsule endoscope according to claim 1 of the present invention is configured to drive a subject by driving a functional circuit housed in a sealed container when the capsule endoscope is inserted into the subject. A capsule endoscope configured to acquire an image of the inside of the container, and a distal end cover that is formed into a substantially hemispherical dome shape having an opening on the proximal end side by an optical material and constitutes a distal end portion of the sealed container; and the distal end cover An interior member disposed inside the base end side, a lens unit that is held by the interior member and forms an image of light incident through the distal end cover, and is configured between the distal end cover and the interior member, When the interior member is inserted into the proximal end side of the distal end cover, it engages with each other so that the pupil center of the distal end cover and the pupil center of the lens unit coincide with each other on the same optical axis. Characterized in that a positioning means that.

  The capsule endoscope according to a second aspect of the present invention is the capsule endoscope according to the first aspect, wherein the positioning means engages the tip cover and the interior member so as to be relatively rotatable about an optical axis. It is characterized by being.

  The capsule endoscope according to a third aspect of the present invention is the capsule endoscope according to the first aspect described above, wherein the positioning means protrudes inward from the inner peripheral surface of the tip cover, and the tip surface of the interior member. And a protrusion that restricts the inclination of the optical axis of the lens unit with respect to the optical axis of the tip cover and positions the pupil center of the lens unit at the pupil center of the tip cover. To do.

  The capsule endoscope according to claim 4 of the present invention is characterized in that, in claim 3 described above, the protruding portion is provided on the entire inner periphery of the tip cover.

  The capsule endoscope according to a fifth aspect of the present invention is the capsule endoscope according to the first aspect, wherein the lens unit includes a lens member and a cylindrical lens frame that holds the lens member. It has a light-shielding portion for limiting incident light around the entrance side of the lens member.

  The capsule endoscope according to claim 6 of the present invention is the capsule endoscope according to claim 1 described above, wherein at least a portion that is an incident range of light passing through the lens unit is formed with a uniform thickness in the tip cover. It is characterized by.

  According to a seventh aspect of the present invention, in the capsule endoscope according to the first aspect described above, at least a part of the interior member is disposed inside the distal end cover when the interior member is disposed inside the proximal end side of the distal end cover. A wiring board having an outer diameter that fits to the peripheral surface, and holds the lens unit through a through-hole provided in the center of the wiring board, and the surface located on the front end side of the wiring board A light-emitting element for irradiating a subject with illumination light through a tip cover is mounted.

  According to the present invention, it is possible to provide a capsule endoscope that can obtain a good in-vivo image without causing complicated assembly work.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of a capsule endoscope according to the invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiment.

  FIG. 1 is a cross-sectional side view showing a capsule endoscope according to an embodiment of the present invention. The capsule endoscope C exemplified here has a size that can be inserted into the body from the mouth of a subject, for example, a person or animal, and after being inserted into the body, until it is excreted outside the body. Image data as information inside the digestive tract such as the stomach, small intestine, large intestine, etc., and an internal power source 10 and a wiring board 20 constituting a functional circuit that executes a predetermined function set in advance, and these A capsule-like sealed container 100 that houses the internal power supply 10 and the wiring board 20 is provided.

  The internal power supply 10 is for accumulating drive power supplied to the functional circuit. In the present embodiment, three general-purpose button-type silver oxide batteries (hereinafter simply referred to as button-type batteries 10) are applied as the internal power supply 10. The number of button-type batteries 10 to be applied is not necessarily three, and may be determined as appropriate according to the time for which the functional circuit is to be operated.

  The wiring board 20 is a composite board (hereinafter, referred to as a rigid flexible wiring board 20 as appropriate) including a plurality of rigid wiring board portions 20R and a flexible wiring board portion 20F that connects the plurality of rigid wiring board portions 20R in series. is there. The rigid wiring board portion 20R is constituted by a relatively rigid base material such as glass epoxy resin, for example, and is a portion on which various functional components and electronic components for mainly constituting a functional circuit are mounted. The flexible wiring board portion 20F is configured by a flexible film-like base material such as polyimide or polyester resin, and is mainly a cable for electrically connecting a plurality of rigid wiring board portions 20R to each other. Part.

  The functional circuit configured on the wiring board 20 is, for example, an illumination function that irradiates illumination light to a predetermined imaging range, an imaging function that converts reflected light due to illumination light irradiation into an image signal, and power supplied from the internal power supply 10 Switch function to turn off / off, voltage conversion function to adjust the internal power supply voltage to a preset constant voltage, transmission processing function to modulate / amplify a given image signal, modulated / amplified image signal It has a plurality of preset functional parts necessary for acquiring image data, such as an antenna function for external output as a radio signal and a control function for comprehensively controlling these functions.

  In the present embodiment, the plurality of functional parts are divided into rigid wiring board parts 20R. That is, the rigid wiring board part 20R of the wiring board 20 includes an illumination board part 20R1 for realizing an illumination function, an imaging board part 20R2 for realizing an imaging function and a control function, and a switch for realizing a switch function. A board 20R3, a power board 20R4 for realizing a voltage conversion function, a transmission board 20R5 for realizing a transmission processing function, and an antenna board 20R6 for realizing an antenna function are provided.

  As shown in FIGS. 1 to 5 and 6, the illumination board portion 20 </ b> R <b> 1 has a disk shape, has a mounting hole 21 at the center thereof, and a linear portion 22 </ b> R <b> 1 at a part of the peripheral surface. have. The mounting hole 21 is a portion in which a lens unit 30 to be described later is mounted, and has a small-diameter circular shape. The straight line portion 22R1 is formed by linearly cutting the peripheral edge portion of the illumination board portion 20R1, and is provided in a direction perpendicular to the extending direction of the flexible wiring board portion 20F.

  In order to realize the illumination function, the light emitting element 23 such as a white diode is mounted on one mounting surface of the lighting board 20R1, and the drive circuit 24 for the light emitting element 23 is configured on the other mounting surface. The electronic parts are mounted. As shown in FIG. 4, four light emitting elements 23 are mounted at angular positions that are the same distance from the mounting hole 21 and are equidistant from each other with the mounting hole 21 as the center. The number of the light emitting elements 23 is not necessarily four, and may be 3 or less or 5 or more as long as the illumination function can be sufficiently performed.

  As shown in FIGS. 1 to 4, 7, and 8, the imaging substrate portion 20 </ b> R <b> 2 has a disk shape that is the same as or slightly smaller in diameter than the illumination substrate portion 20 </ b> R <b> 1, and is linear at two locations on the peripheral surface. A portion 22R2 is provided. The straight line portion 22R2 is formed by linearly cutting the peripheral edge portion of the imaging substrate portion 20R2, and is provided in a direction parallel to each other and perpendicular to the extending direction of the flexible wiring board portion 20F.

  On the imaging board portion 20R2, a processor element (hereinafter simply referred to as DSP25) such as a DSP (Digital Signal Processor) that realizes a control function and an electronic component are mounted on one mounting surface, while the other mounting surface is mounted. An CCD (Charge Coupled Device) for realizing the imaging function, an imaging element (hereinafter simply referred to as the CCD 26) such as a CMOS (Complementary Metal Oxide Semiconductor), and electronic components for configuring the drive circuit 27 of the CCD 26 are mounted. is there.

  As shown in FIGS. 1 and 12, the CCD 26 is provided with a holding frame 29 on the pixel surface via a cover glass 28, and a lens unit 30 is mounted inside the holding frame 29.

  The holding frame 29 includes a cylindrical tubular portion 29a having a diameter larger than the pixel surface of the CCD 26, and a base portion 29b integrally formed at the base end portion of the tubular portion 29a. Is attached to the cover glass 28 via the base portion 29b in a state where the axis of is aligned with the central axis of the visual field in the CCD 26.

  The lens unit 30 includes a cylindrical lens frame 31 and a pair of lens members 32 and 33. The lens frame 31 has a relatively thick cylindrical slide part 31a having an outer diameter that fits into the cylindrical part 29a of the holding frame 29, and the axial center of the slide frame 31a is aligned with the tip of the slide part 31a. A mounting portion 31b having a relatively thin cylindrical shape having an outer diameter that fits in the mounting hole 21 of the illumination board portion 20R1, and an inward direction from the entire circumference of the tip portion of the mounting portion 31b. The light-shielding portion 31c projecting toward is integrally formed. On the outer peripheral surface of the lens frame 31, a shoulder portion 31d is formed between the slide portion 31a and the mounting portion 31b. The light shielding part 31 c is a part corresponding to an entrance pupil for defining the observation range of the image data with respect to the lens unit 30. The outer end surface of the light shielding portion 31c is recessed in a tapered shape so as to gradually go to the other end side as it goes to the central axis. The pair of lens members 32 and 33 are mounted inside the lens frame 31 with the color member 34 interposed therebetween and the optical axes of the pair of lens members 32 and 33 being matched with each other. This lens unit 30 is slidably disposed on the cylindrical portion 29a of the holding frame 29 via the slide portion 31a with the light shielding portion 31c facing outward, and the optical axis with respect to the pixel surface of the CCD 26. Focus adjustment can be performed by appropriately changing the position in the direction.

  In addition, as shown in FIG. 8, the imaging board 20R2 is provided with a plurality of pad portions 35 serving as external terminals in a portion outside the mounting area for electronic components and the like on one mounting surface. These pad portions 35 are conductor portions exposed in a circular shape on the mounting surface of the imaging substrate portion 20R2, and function as external power supply terminals for directly supplying power from an external power source (not shown) to the functional circuit. And a portion functioning as an external input terminal for inputting an initial set value of the functional circuit to a memory to be described later.

  As shown in FIGS. 1 to 4 and 9, the switch board portion 20R3 has a disk shape that is the same as or slightly smaller in diameter than the imaging board portion 20R2, and has a circumferential surface similar to the imaging board portion 20R2. The straight portion 22R3 is provided at two places, and a relief hole 36 is provided at the center portion thereof. The straight portion 22R3 is formed by linearly cutting the peripheral portion of the switch substrate portion 20R3, and is provided in a direction parallel to each other and perpendicular to the extending direction of the flexible wiring board portion 20F. The escape hole 36 is for accommodating a part of a reed switch 37 described later, and has a long hole shape extending along the straight portion 22R3.

  The switch board portion 20R3 is mounted with a reed switch 37 for realizing a switch function in such a manner that a part of the switch board portion 20R3 is accommodated in the clearance hole 36 from one mounting surface side. Electronic parts such as a memory 38 are mounted on a portion around 36.

  The reed switch 37 operates according to the presence or absence of a magnetic field, and turns on / off the power supplied from the internal power supply 10. In the present embodiment, the power supply from the internal power supply 10 is turned off when a magnetic field is applied by, for example, bringing a permanent magnet closer, while the power supply from the internal power supply 10 is continuously applied when the magnetic field is not applied. The one that operates to turn on is applied.

  The memory 38 is volatile storage means for storing data necessary for driving the functional circuit, such as an initial set value of the DSP 25. Examples of the initial setting value of the DSP 25 include data for correcting defects caused by the white balance coefficient of the CCD 26 and variations in the CCD 26, pixel defect address data of the CCD 26, and the like. As shown in FIG. 1, a disc spring-like positive electrode contact member 39 serving as a contact point with respect to the positive electrode of the button-type battery 10 is provided on the other mounting surface of the switch board portion 20R3.

  1 to 4 and FIG. 10, the power supply board portion 20R4 has a smaller diameter than the switch board portion 20R3 and further has a smaller disk shape than the negative electrode of the button-type battery 10. Similar to the substrate portion 20R3, linear portions 22R4 are provided at two locations on the peripheral surface. The straight portion 22R4 is formed by linearly cutting the peripheral portion of the power supply substrate portion 20R4, and is provided in a direction parallel to each other and perpendicular to the extending direction of the flexible wiring board portion 20F.

  A plurality of electronic components for realizing a voltage conversion function are mounted on one mounting surface on the power supply board 20R4, and, for example, a DCDC converter 40 is configured. Although not clearly shown in the drawing, a negative electrode contact member serving as a contact point with respect to the negative electrode of the button-type battery 10 is provided on the other mounting surface of the power supply board 20R4.

  As shown in FIG. 1, FIG. 2, FIG. 4, and FIG. 11, the transmission board portion 20R5 has a disk shape that is the same as or slightly smaller in diameter than the switch board portion 20R3, and is similar to the illumination board portion 20R1. A straight portion 22R5 is provided on a part of the peripheral surface. The straight portion 22R5 is configured by linearly cutting the peripheral portion of the transmission board portion 20R5, and has a plurality of through-hole lands 41.

  The transmission board portion 20R5 has one mounting surface connected to an end portion of the flexible wiring board portion 20F through the through-hole land 41, while the other mounting surface has a plurality of transmission processing functions for realizing a transmission processing function. An electronic component is mounted, and for example, an RF (Radio Frequency) unit 42 is configured.

  As shown in FIGS. 1 and 11, the antenna substrate portion 20R6 is formed in a disk shape having a smaller diameter than the transmission substrate portion 20R5, and is parallel to each other on the other mounting surface side of the transmission substrate portion 20R5. It is attached. An antenna 43 is configured on the antenna substrate portion 20R6 by laying a conducting wire in a substantially spiral shape. Although not explicitly shown in the figure, both ends of the conducting wire constituting the antenna 43 are electrically connected to the circuit portion of the transmission board 20R5, respectively.

  As shown in FIGS. 2 to 4, these rigid wiring board portions 20 </ b> R include an illumination board portion 20 </ b> R <b> 1, an imaging board portion 20 </ b> R <b> 2, a switch board portion 20 </ b> R <b> 3, a power supply board portion 20 </ b> R <b> 4, and a transmission board portion 20 </ b> R5 in this order. It is configured in advance to be connected in a straight line by the flexible wiring board portion 20F. Among these, the illumination board part 20R1 to the power supply board part 20R4 are configured as an integral flat plate together with the flexible wiring board part 20F, and after mounting electronic components on each, the antenna board part is provided at the end of the flexible wiring board part 20F. By connecting the transmission board portion 20R5 integrated with 20R6, a straight rigid-flex wiring board 20 is obtained.

  Here, by applying a general mounting technique to the rigid wiring board portion 20R from the illumination board portion 20R1 to the power supply board portion 20R4 configured in an integrated flat plate shape together with the flexible wiring board portion 20F, an electronic component can be obtained. Can be easily implemented. In addition, since the rigid wiring board portion 20R and the flexible wiring board portion 20F that are integrally formed are already electrically connected at the stage of manufacture, there is no need for separate connection between them. Therefore, it becomes possible to shorten the manufacturing process and facilitate the assembly work.

  The flexible wiring board portions 20F disposed between the rigid wiring board portions 20R are configured to have different widths and lengths as necessary. Among these, the flexible wiring board portion 20F disposed between the switch substrate portion 20R3 and the power supply substrate portion 20R4 has a two-divided configuration by a slit 20FS that is relatively wide and formed along the longitudinal direction.

  With respect to the rigid flexible wiring board 20 configured in a straight line, first, an operation check inspection of the functional circuit is performed, and then, as shown in FIG. 1, flexible wiring is performed in such a manner that adjacent rigid wiring board portions 20R face each other. The button 20 is sandwiched and held in a state in which the plate portion 20F is appropriately bent and the direction is matched between the positive contact member 39 of the switch substrate portion 20R3 and the negative contact member (not shown) of the power supply substrate portion 20R4. By doing so, it is blocked in a cylindrical shape as an interior member that can be accommodated in the sealed container 100.

  The operation check inspection is for checking whether or not the function circuit operates normally when power is supplied to the functional circuit. In the case of the rigid flexible wiring board 20 having the above-described configuration, it is possible to perform an operation check inspection of the functional circuit while maintaining a straight line shape as shown in FIGS. That is, according to the rigid flexible wiring board 20 in which the pad portion 35 is provided on the imaging substrate portion 20R2, for example, the power supply to the functional circuit is made by bringing the needle electrode of the external power supply into contact with the pad portion 35 that functions as the external power supply terminal. It can be performed. Therefore, even before the button-type battery 10 as the internal power source is held between the positive contact member 39 and the negative contact member (not shown), such as a production line of the rigid flexible wiring board 20, the operation of the functional circuit It is possible to perform a confirmation inspection and guarantee its reliable operation.

  In addition, if an operation check is performed using an external power supply, the button-type battery 10 serving as an internal power supply is not consumed at all. Therefore, even when a relatively small button-type battery 10 is applied, the function of the button-type battery 10 is improved. A sufficient operation time of the circuit can be secured. Further, if necessary, an initialization process such as inputting an initial set value of a functional circuit to the memory 38 of the switch board unit 20R3 through the pad unit 35 functioning as an external input terminal may be performed along with the supply of power from an external power source. Is possible.

  When the flexible wiring board portion 20F is bent after the operation check inspection, as shown in FIG. 1, the other mounting surface of the illumination substrate portion 20R1 and the other mounting surface of the imaging substrate portion 20R2 are opposed to each other, The mounting portion 31b of the lens unit 30 is fitted into the mounting hole 21 of the substrate unit 20R1. In the lens unit 30 fitted in the mounting hole 21 of the illumination board part 20R1, the shoulder part 31d formed between the slide part 31a and the mounting part 31b of the lens frame 31 contacts the other mounting surface of the illumination board part 20R1. In contact with each other, the illumination member 20R1 is positioned and held in a state where the optical axes of the lens members 32 and 33 and the visual field center axis of the CCD 26 are aligned with the axis of the illumination substrate 20R1, respectively. Even in this state, if the cylindrical portion 29a of the holding frame 29 is slid with respect to the slide portion 31a of the lens frame 31, the distance between the CCD 26 and the imaging board portion 20R2 changes with respect to the lens members 32 and 33. Thus, the focus adjustment of the CCD 26 can be performed. After the focus adjustment of the CCD 26 is performed, an insulating sealing resin P is filled and cured between the illumination substrate unit 20R1 and the imaging substrate unit 20R2, and the two are held in a combined state.

  One mounting surface of the switch board portion 20R3 is opposed to the one mounting surface of the imaging board portion 20R2, and the other mounting surface of the power board portion 20R4 is further mounted on the other mounting surface of the switch board portion 20R3. The button-type battery 10 is sandwiched and held between the positive electrode contact member 39 and a negative electrode contact member (not shown) by bending the flexible wiring board portion 20F so that the surfaces face each other.

  After the button-type battery 10 is sandwiched and held between the switch board portion 20R3 and the power supply board portion 20R4, the button-type battery 10 is covered by covering the heat-shrinkable tube 44 and heating it appropriately. Are pressed and held together with the switch substrate portion 20R3 and the power supply substrate portion 20R4. Thereafter, an insulating sealing resin P is filled and cured between the imaging substrate unit 20R2 and the switch substrate unit 20R3, and between the power supply substrate unit 20R4 and the transmission substrate unit 20R5, so that each rigid wiring board unit 20R Keep the space connected.

  When the cylindrical interior member is configured as described above, the flexible wiring board portion 20F is extended from each linear portion 22R in a direction perpendicular to each rigid wiring board portion 20R having a disk shape. According to the rigid flexible wiring board 20, it is possible to easily and surely bend each flexible wiring board portion 20F along the respective straight portions 22R from a portion close to the rigid wiring board portion 20R. In addition, each of the straight portions 22R is formed by cutting out the rigid wiring board portion 20R having a disk shape, so that the flexible wiring board portion 20F is bent as shown in FIGS. 5 and 6, for example. Can also be stored in the excised part. Furthermore, since the flexible wiring board portion 20F located at the outer peripheral portion of the button-type battery 10 is divided into two by the slit 20FS along the longitudinal direction, as shown in FIGS. 10 and 11, the button-type battery It closely follows the 10 circumferential surfaces. As a result, it is possible to prevent a situation in which the outer diameter of each rigid wiring board 20R and the outer diameter of the button-type battery 10 are greatly increased by the flexible wiring board 20F.

  On the other hand, the sealed container 100 that accommodates the button-type battery 10 and the rigid flexible wiring board 20 includes a container body 110 and a tip cover 120 that are divided.

  As shown in FIGS. 1 and 13, the container body 110 includes a bottom portion 111 that forms a substantially hemispherical dome shape, and a substantially cylindrical body portion 112 that extends continuously from the bottom portion 111. In addition, the body 112 is integrally formed of a synthetic resin material. As the synthetic resin material for molding the container body 110, for example, cycloolefin polymer, polycarbonate, acrylic, polysulfone, and urethane can be used. However, when considering the strength of the container body 110, polysulfone can be applied. preferable.

  Although not clearly shown in the drawing, a draft angle is set in the body portion 112 of the container main body 110, and the body portion 110 is formed so as to have a small diameter toward the opening side of the tip. As shown in FIG. 1, the dimensions of the container body 110 can be accommodated when the rigid flexible wiring board 20 and the button-type battery 10 that are blocked as an interior member are inserted from the antenna board part 20R6 side, and The gap between the housed interior member is minimized.

  Further, an engagement groove 113 is formed over the entire circumference of the inner peripheral surface of the body portion 112 of the container main body 110 that is located slightly proximal to the opening at the front end.

  As shown in FIGS. 1, 14, and 15, the front end cover 120 includes a dome portion 121 that forms a substantially hemispherical dome shape, and an engagement portion 122 that extends in a cylindrical shape from the base end portion of the dome portion 121. The dome portion 121 and the engaging portion 122 are integrally formed of a synthetic resin material that is an optical material. As the synthetic resin material for molding the tip cover 120, cycloolefin polymer, polycarbonate, acrylic, polysulfone, urethane can be used, but when considering the optical performance and strength of the tip cover 120 in particular, cycloolefin polymer, Alternatively, it is preferable to apply polycarbonate.

  The tip cover 120 has a dome portion 121 having an outer diameter substantially the same as a tip outer diameter of the body portion 112 in the container main body 110, while an engagement portion 122 is fitted on the inner periphery of the tip end of the body portion 112 in the container main body 110. The outer diameter of the dome portion 121 is continuous with the outer surface of the body portion 112 through the engagement portion 122 when mounted on the distal end portion of the container body 110. It is possible to fit to the inner periphery of the front end portion of the body portion 112.

  An engagement protrusion 123 is provided over the entire circumference of the engagement portion 122 of the tip cover 120 at a portion corresponding to the engagement groove 113 of the container body 110. The engagement protrusion 123 engages with the engagement groove 113 of the container main body 110 when the front end cover 120 is attached to the front end portion of the body 112, so that the front end cover 120 is inadvertently dropped from the container main body 110. This is intended to prevent this. Furthermore, the inner periphery of the engaging portion 122 is configured to have an inner diameter that allows the illumination board portion 20R1 of the rigid flexible wiring board 20 to be fitted therein.

  Further, the tip cover 120 has a light transmitting portion 121a set in a range (a region surrounded by a two-dot chain line in FIG. 1) that is a predetermined symmetric region from the center of curvature of the dome portion 121. The pupil part 121b is provided in the perimeter of the site | part which becomes an outer peripheral side rather than the part 121a.

  The translucent part 121a and the pupil part 121b are parts that define the observation range of the image data with respect to the tip cover 120. The translucent part 121a of the tip cover 120 is formed in a uniform and uniform thickness. On the other hand, the pupil part 121b is formed to have a thickness greater than that of the light transmitting part 121a, and constitutes a protruding part 124 that bulges inward from the inner peripheral surface of the engaging part 122. ing. The projecting portion 124 has a contact surface 125 located on the base end side extending in a direction perpendicular to the axis of the front end cover 120, and is in contact with and engaged with one mounting surface of the illumination board portion 20R1. In this case, the optical axis of the lens unit 30 coincides with the axial center of the tip cover 120, and the center of the entrance pupil with respect to the lens unit 30 on the optical axis is the center of curvature of the tip cover 120 (= the entrance pupil of the tip cover 120). (Center). The protrusion 124 has an inner diameter set larger than the mounting area of the light emitting element 23 on the illumination board 20R1, and interferes with the light emitting element 23 even when the illumination board 20R1 is rotated about its axis. There is nothing.

  When the rigid flexible wiring board 20 and the button-type battery 10 that are formed into blocks are accommodated in the sealed container 100 configured as described above, as shown in FIG. 13, the illumination board 20R1 is previously covered with the tip cover 120. Then, an adhesive is applied to the inner peripheral surface of the container body 110, while an insulating sealing resin P is applied to the periphery of the rigid flexible wiring board 20 and the button-type battery 10, and from this state, an interior member is applied. Is inserted into the container body 110 and the engagement protrusion 123 of the tip cover 120 is engaged with the engagement groove 113 of the container body 110. In a state where the engagement protrusion 123 of the tip cover 120 is engaged with the engagement groove 113 of the container body 110, the two are rotated as they are so that the adhesive between them is spread in the entire circumferential direction. Is preferred.

  In this case, as described above, the optical axis of the lens unit 30 is aligned with the axial center of the tip cover 120 as long as one mounting surface of the illumination board 20R1 is brought into contact with the contact surface 125 of the tip cover 120. Therefore, the center of the entrance pupil with respect to the lens unit 30 matches the center of curvature of the tip cover 120. In addition, when the illumination board portion 20R1 is inserted into the engagement portion 122, the protruding portion 124 of the tip cover 120 does not interfere with the light emitting element 23 of the illumination board portion 20R1, so that the axis center of the both is around. There is no need to consider attitude. Therefore, it is not necessary to adjust the position of the optical system with respect to incident light when assembling, and the assembling work can be performed very easily.

  When the adhesive that has infiltrated between the inner peripheral surface of the container body 110 and the outer peripheral surface of the engaging portion 122 in the tip cover 120 comes to ensure a desired watertightness between them and is put into the body cavity In addition, there is no possibility that a liquid such as a body fluid enters the inside of the sealed container 100. In particular, since the engagement protrusion 123 and the engagement groove 113 are engaged with each other between the distal end cover 120 and the distal end portion of the container body 110, a post-treatment process such as sterilization performed after assembly is performed. Even in this case, the adhesive between them is not peeled off, and there is no possibility of causing a situation where the interior member generates heat or a short circuit due to the intrusion of body fluid.

  FIG. 16 is a conceptual diagram for explaining an example of use of the capsule endoscope C described above. Hereinafter, the operation of the capsule endoscope C will be briefly described with reference to this figure.

  First, when the capsule endoscope C according to the present embodiment is taken out from the package 200 containing a permanent magnet (not shown), the reed switch 37 is activated, and the DCDC converter 40 is removed from the button-type battery 10 which is an internal power source. After that, the power supply to the functional circuit is continuously turned on.

  When the subject wearing the jacket 201 swallows the capsule endoscope C from this state, the image data of the subject is acquired until each part of the functional circuit is driven by the command from the DSP 25 and excreted outside the body. It becomes possible. More specifically, the light emitted from the light emitting element 23 is irradiated to the observation range of the subject such as the stomach, small intestine, and large intestine through the translucent part 121a of the tip cover 120, and incident through the translucent part 121a of the tip cover 120. The reflected light is coupled to the CCD 26 through the lens unit 30, and the reflected light coupled to the CCD 26 is output as an image signal.

  Further, the image signal output from the CCD 26 is modulated / amplified by the RF unit 42, wirelessly transmitted to the outside from the antenna 43, and an external storage device 203 of the receiver 202 attached to the jacket 201, for example, a compact flash (R). It is sequentially stored as image data in the memory. The image data stored in the external storage device 203 is visualized on the display 205 through the computer 204, for example, and becomes a diagnosis target through a doctor or a nurse.

  During these operations, according to the capsule endoscope C described above, the optical axis of the lens unit 30 matches the axis of the tip cover 120, and the center of the entrance pupil with respect to the lens unit 30 is the curvature of the tip cover 120. Since it coincides with the center, all of the incident light incident from the translucent part 121 a provided in the dome part 121 of the tip cover 120 is imaged on the pixel surface of the CCD 26 by the lens members 32 and 33 of the lens unit 30. In addition, since the translucent portion 121a is formed in a uniform and uniform thickness, extremely good image data can be acquired.

  In addition, the positioning of the optical system related to the incident light can be accurately performed without requiring any adjustment work if one mounting surface of the illumination board 20R1 is brought into contact with the contact surface 125 of the tip cover 120. Therefore, there is no possibility that the assembly work will be complicated.

  Further, since the light shielding portion 31c is provided in the lens frame 31 that holds the lens members 32 and 33, the incident light that has passed through the pupil portion 121b that is on the outer peripheral side of the light transmitting portion 121a in the dome portion 121 of the tip cover 120. Can reliably block this, and can effectively prevent the occurrence of flare in the image data.

  In the above-described embodiment, the contact surface 125 of the protrusion 124 provided on the tip cover 120 and the illumination board 20R1 are in contact with each other so as to be relatively rotatable. However, it is not always necessary to make the contact surface 125 of the tip cover 120 and the illumination board portion 20R1 contact each other so as to be relatively rotatable. Further, the protruding portion 124 of the tip cover 120 does not necessarily have to be formed over the entire circumference, and it is sufficient that the protruding portion 124 is in contact with at least one of the mounting surfaces of the illumination board portion 20R1 at three locations.

1 is a cross-sectional side view of a capsule endoscope according to an embodiment of the present invention. FIG. 2 is a development plan view of a wiring board that is an interior member of the capsule endoscope shown in FIG. 1. FIG. 3 is a cross-sectional side view of FIG. 2. FIG. 3 is a bottom view of FIG. 2. It is the VV sectional view taken on the line in FIG. It is the VI-VI sectional view taken on the line in FIG. It is the VII-VII sectional view taken on the line in FIG. It is the VIII-VIII sectional view taken on the line in FIG. It is the IX-IX sectional view taken on the line in FIG. It is the XX sectional view taken on the line in FIG. It is the XI-XI sectional view taken on the line in FIG. It is an expanded sectional view which shows the principal part of the interior member applied to the capsule endoscope shown in FIG. FIG. 2 is an exploded cross-sectional side view showing a state in which the interior member of the capsule endoscope shown in FIG. 1 is housed in a sealed container. It is a cross-sectional side view of the front-end | tip cover applied to the airtight container of the capsule endoscope shown in FIG. It is the XV-XV sectional view taken on the line in FIG. It is a conceptual diagram for demonstrating the usage example of a capsule type | mold endoscope. It is a cross-sectional side view showing a conventional capsule endoscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Button type battery 20 Rigid flexible wiring board 20F Flexible wiring board part 20FS Slit 20R Rigid wiring board part 20R1 Illumination board part 20R2 Imaging board part 20R3 Switch board part 20R4 Power supply board part 20R5 Transmission board part 20R6 Antenna board part 21 Mounting hole 22R1 Straight line Portion 22R2 straight portion 22R3 straight portion 22R4 straight portion 22R5 straight portion 23 light emitting element 24 light emitting element drive circuit 25 DSP
26 CCD
27 CCD drive circuit 28 Cover glass 29 Holding frame 29a Cylindrical part 29b Base 30 Lens unit 31 Lens frame 31a Slide part 31b Mounting part 31c Light-shielding part 31d Shoulder part 32, 33 Lens member 34 Color member 35 Pad part 36 Escape hole 37 Reed switch 38 Memory 39 Positive contact member 40 DCDC converter 41 Through-hole land 42 RF unit 43 Antenna 44 Heat-shrinkable tube 100 Sealed container 110 Container body 111 Bottom portion 112 Body portion 113 Engaging groove 120 Tip cover 121 Dome portion 121a Translucent portion 121b Pupil part 122 Engagement part 123 Engagement protrusion 124 Protrusion part 125 Contact surface C Capsule type endoscope

Claims (7)

In a capsule endoscope that acquires an image of the inside of a subject by driving a functional circuit housed in the inside of the sealed container when it is inserted into the subject,
A tip cover that forms a substantially hemispherical dome shape whose base end side is opened by an optical material, and constitutes a tip portion of the sealed container;
An interior member disposed inside the proximal end of the distal end cover;
A lens unit that is held by the interior member and forms an image of light incident through the tip cover;
A pupil center of the tip cover and a pupil of the lens unit are formed between the tip cover and the interior member, and are engaged with each other when the interior member is inserted inside the proximal end of the tip cover. A capsule endoscope comprising: positioning means for aligning the centers with each other on the same optical axis.   The capsule endoscope according to claim 1, wherein the positioning means engages the tip cover and the interior member so as to be relatively rotatable about an optical axis.   The positioning means protrudes inward from the inner peripheral surface of the tip cover and abuts against the tip surface of the interior member, thereby regulating the inclination of the optical axis of the lens unit with respect to the optical axis of the tip cover. The capsule endoscope according to claim 1, further comprising a protrusion that positions a pupil center of the lens unit at a pupil center of the tip cover.   The capsule endoscope according to claim 3, wherein the protrusion is provided on the entire inner periphery of the tip cover.   The lens unit includes a lens member and a cylindrical lens frame that holds the lens member, and the lens frame includes a light-shielding portion for restricting incident light around the incident side of the lens member. The capsule endoscope according to claim 1.   2. The capsule endoscope according to claim 1, wherein at least a portion that is an incident range of light passing through the lens unit is formed to have a uniform thickness in the tip cover. The interior member includes a wiring board having an outer diameter that fits at least a part of the inner peripheral surface of the tip cover when disposed inside the base end side of the tip cover, and is provided at the center of the wiring board. The lens unit is held through the through-hole, and a light emitting element for irradiating the subject with illumination light through the tip cover is mounted on the surface located on the tip side of the wiring board. The capsule endoscope according to claim 1.

Images