Imaging module and endoscope

Abstract

[Problem] To provide an ultracompact imaging module 30 that can be manufactured easily. [Solution] An imaging module 30 comprises a camera unit 32 having an external electrode 32C on a lower surface F32, and a rigid substrate 31. The rigid substrate 31 has a first surface F1 on which the camera unit 32 is mounted; a second surface F2 that is on an opposite side of, and parallel to, the first surface F1; a third surface F3 that extends from the first surface F1 at a first angle θ1; and a fourth surface F4 that extends from the second surface F2 and is parallel to the third surface F3. The rigid substrate 31 further has a first through hole H31 that passes through the third surface F3 and the fourth surface F4 and is perpendicular to the first surface F1.

Description

Imaging module and endoscope

[0001] The present invention relates to an imaging module disposed at the tip of an insertion section of an endoscope, and to an endoscope having an imaging module disposed at the tip of the insertion section.

[0002] In an oblique-viewing endoscope, the direction in which the camera unit captures images (optical axis direction) is inclined at a predetermined angle with respect to the longitudinal direction of the distal end of the insertion section.

[0003] International Publication No. 2023 / 276006 discloses an oblique-viewing endoscope having an imaging module in which a camera unit is mounted on one surface of a molded circuit device. By using a bent wiring board with a bent portion as the molded circuit device, it becomes easy to arrange an ultra-compact imaging module in a small-diameter endoscope.

[0004] International Publication No. 2023 / 276006

[0005] When forming through-hole wiring to enhance the functionality of a wiring board, it is essential to align the wiring patterns on the two main surfaces. However, this is not easy with ultra-small, bent wiring boards.

[0006] An object of an embodiment of the present invention is to provide an ultra-compact imaging module that is easy to manufacture, and an endoscope having an ultra-compact imaging module that is easy to manufacture.

[0007] An imaging module according to an embodiment of the present invention comprises a camera unit having an external electrode on its underside, and a rigid substrate having a first surface on which the camera unit is mounted, a second surface opposite the first surface and parallel to the first surface, a third surface extending from the first surface at a first angle, and a fourth surface extending from the second surface and parallel to the third surface, wherein the rigid substrate has a first through-hole that penetrates between the third surface and the fourth surface and is perpendicular to the first surface, or a groove that is provided on a side surface of the rigid substrate from the third surface to the fourth surface and is perpendicular to the first surface.

[0008] An endoscope according to an embodiment of the present invention has an imaging module at the tip of an insertion section, and the imaging module includes: a camera unit having an external electrode on its underside; and a rigid substrate having a first surface on which the camera unit is mounted, a second surface opposite to the first surface and parallel to the first surface, a third surface extending from the first surface at a first angle, and a fourth surface extending from the second surface and parallel to the third surface, and the rigid substrate has a first through-hole that penetrates between the third surface and the fourth surface and is perpendicular to the first surface, or a groove that is provided on a side surface of the rigid substrate from the third surface to the fourth surface and is perpendicular to the first surface.

[0009] According to the embodiments of the present invention, it is possible to provide an ultra-compact imaging module that is easy to manufacture, and an endoscope having an ultra-compact imaging module that is easy to manufacture.

[0010] FIG. 1 is a diagram showing the configuration of an endoscopic system including an endoscope according to an embodiment of the present invention. FIG. 2 is a perspective view of a tip portion of an endoscope according to an embodiment of the present invention. FIG. 3 is a perspective cross-sectional view of the tip portion of an endoscope according to an embodiment of the present invention. FIG. 4 is a perspective view of an imaging module according to a first embodiment of the present invention. FIG. 5 is an exploded cross-sectional view of the imaging module according to the first embodiment of the present invention. FIG. 6 is a top view of the imaging module according to the first embodiment of the present invention. FIG. 7 is a bottom view of the imaging module according to the first embodiment of the present invention. FIG. 8 is a bottom view of a conventional imaging module. FIG. 9 is a perspective view of an imaging module according to a second embodiment of the present invention. FIG. 10 is a perspective view of an imaging module according to a third embodiment of the present invention. FIG. 11 is a cross-sectional view of a hard substrate of the imaging module according to the third embodiment of the present invention.

[0011] As shown in FIG. 1 , an endoscope system 2 including an endoscope 10 according to an embodiment includes the endoscope 10 , a processor 17 , a light source device 18 , and a monitor 19 .

[0012] In the following description, the drawings based on each embodiment are schematic diagrams. The relationship between the thickness and width of each part, the thickness ratio of each part, and the relative angle are different from the actual ones. The drawings also include parts with different dimensional relationships and ratios. Some components are not shown or labeled.

[0013] The endoscope 10 is an oblique-viewing endoscope in which an insertion section 11 is inserted into the body of a subject, captures in-vivo images, and outputs image signals. An operation section 12 having various buttons for operating the endoscope 10 is disposed at the proximal end of the insertion section 11 of the endoscope 10. The insertion section 11 is composed of a distal end section 11A in which an imaging module 30 is disposed, a freely bendable bending section 11B connected to the proximal end of the distal end section 11A, and a flexible section 11C connected to the proximal end of the bending section 11B. The bending section 11B is bent by operating the operation section 12.

[0014] A universal cord 13 extending from the operation unit 12 is connected to a processor 17 and a light source device 18 by a connector 14. A treatment tool is inserted into a treatment tool insertion port 12A of the operation unit 12, as will be described later.

[0015] The processor 17 controls the entire endoscope system 2, and also processes the imaging signal output from the imaging module 30 to output the image signal. The monitor 19 displays the image signal output from the processor 17.

[0016] The light source device 18 has, for example, a white LED. The illumination light emitted by the light source device 18 is guided to the distal end portion 11A by a light guide 40 (see FIG. 3) that passes through the universal cord 13 and the insertion portion 11, and then passes through an illumination lens 41 (see FIG. 3) to illuminate the subject.

[0017] Although the endoscope 10 is a flexible endoscope for medical use, endoscopes in other embodiments may be rigid endoscopes or industrial endoscopes.

[0018] 2 and 3, the distal end frame 20, which is the main component of the distal end portion 11A of the endoscope 10, is a hard component made of a metal such as stainless steel or resin. A bending portion 11B is connected to the proximal end side of the distal end frame 20, which is disposed at the distal end of the insertion portion 11.

[0019] The distal end frame 20 is formed with an elevator storage space S20 that stores an elevator 60. Although not shown, the elevator 60 is inserted from the treatment tool insertion port 12A and is used to control the protrusion direction of the treatment tool that protrudes from the opening of the distal end portion 11A via the channel tube.

[0020] An illumination lens 41, an imaging module 30, and a cleaning nozzle 50 are arranged in this order on the tip frame 20 along the longitudinal axis direction LA of the tip portion 11A. The illumination lens 41 emits illumination light toward the subject. The cleaning nozzle 50 sprays fluid toward the illumination lens 41 and the imaging module 30 to remove deposits.

[0021] 3, the tip frame 20 has a through-hole H60 to which the channel tube is connected, a through-hole H30 to which the imaging module 30 is inserted, a through-hole H40 to which the illumination lens 41 is disposed, and a through-hole H50 to which the cleaning nozzle 50 is connected. For example, the through-hole H30 has openings on the outer surface and the inner surface of the tip frame 20. Although not shown, the tip frame 20 has a large opening on the side, and after multiple components are disposed inside, the opening is closed with a side cover.

[0022] As shown in Figures 4 and 5, the imaging module 30 includes a rigid substrate 31 and a camera unit 32. The rigid substrate 31 has a complex three-dimensional structure. The rigid substrate 31 is a molded interconnect device (MID) in which a conductor pattern is disposed on the surface of an injection-molded three-dimensional object. Unlike a planar wiring board, the use of the rigid substrate 31 allows the shape to have a function, and further allows conductor patterns to be formed on inclined surfaces, vertical surfaces, curved surfaces, through holes, and the like.

[0023] The hard substrate 31, which is a molded circuit device, is made of a resin containing an electroless plating catalyst precursor, and the catalyst precursor becomes an electroless plating catalyst only in the laser irradiated area. The electroless plating catalyst is also formed on the wall surfaces of the through holes formed by the laser irradiation.

[0024] The rigid substrate 31 is a bent wiring board having a first surface F1, a second surface F2 located on the opposite side of the first surface F1 and parallel to the first surface F1, a third surface F3 extending from the first surface F1 at a first angle θ1, and a fourth surface F4 extending from the second surface F2 and parallel to the third surface F3. That is, the acute angle θ2 formed by the second surface F2 and the fourth surface F4 is the same as the first angle θ1.

[0025] The hard substrate 31 is surrounded by a frame-shaped wall 31W and has a recess R31 with a first surface F1 as its bottom surface. In other words, the first surface F1 is the bottom surface of the recess R31 that houses the camera unit 32. The elongated hard substrate 31 is fixed to the tip frame 20 so that the long axis direction LA is the same as the long axis direction LA of the tip portion 11A.

[0026] The camera unit 32 is housed in the recess R31 of the hard substrate 31. That is, the camera unit 32 is mounted on the first surface F1 of the hard substrate 31. The camera unit 32 includes an imaging optical system 32A and an imaging element 32B. The imaging element 32B is a CCD, CMOS, or the like that converts the subject image collected by the imaging optical system 32A into an electrical signal. The imaging element 32B may include a cover glass.

[0027] The imaging optical system 32A is made up of multiple optical elements (lenses, filters, etc.). The imaging optical system 32A is fabricated by cutting a laminated wafer in which multiple optical wafers, each including multiple optical elements, are stacked. Multiple external electrodes 32C are disposed on the bottom surface F32 of the imaging element 32B. A ball grid array made up of solder balls, gold bumps, etc. is disposed on the external electrodes 32C.

[0028] The optical axis O of the camera unit 32 is perpendicular to the first surface F1. The recess R31, which is provided with sealing resin 39 between the wall surface of the recess R31 and the side surface of the camera unit 32, is not an essential component of the hard substrate 31. However, the hard substrate 31 having the recess R31 not only can stably hold the camera unit 32, but also has high reliability because the side surface of the camera unit 32 is covered by the wall surface of the recess R31 and the sealing resin 39.

[0029] The hard substrate 31 has a plurality of first electrodes 31A, a plurality of second electrodes 31B, a plurality of through-wires 31C, and a plurality of wires 31D. The first electrodes 31A, the second electrodes 31B, the through-wires 31C, and the wires 31D are conductive electroless plated films made of, for example, copper, nickel, gold, or the like.

[0030] The first electrode 31A provided on the first surface F1 is joined to an external electrode 32C of the camera unit 32. The second electrode 31B provided on the second surface F2 is connected to the first electrode by a through-wire 31C. Wiring 31D extends from the second electrode 31B to the fourth surface F4. An electronic component such as a chip capacitor is mounted on the wiring 31D, and a cable is further joined to the end of the fourth surface F4.

[0031] The first electrode 31A, the second electrode 31B, and the wiring 31D may be arranged by screen printing, sputtering, metal vapor deposition, etc. An electronic component such as a chip capacitor is mounted on the wiring 31D extending from the second electrode 31B, and a cable is further joined to the end of the wiring 31D.

[0032] Here, the first angle θ1 is, for example, greater than 10 degrees and less than 30 degrees. If the first angle θ1 is within this range, the imaging module 30 can be efficiently disposed in the through-hole H30 of the tip frame 20. However, if the first angle θ1 is greater than the lower limit, it is not easy to align the position of the first electrode 31A on the first surface F1 of the bent hard substrate 31 with the position of the second electrode 31B (through wiring 31C) on the third surface F3, as will be described later.

[0033] For this reason, the hard substrate 31 has a first through-hole H31 that penetrates the third face F3 and the fourth face F4 and is perpendicular to the first face F1. The first through-hole H31 is used as an alignment mark for aligning the positions of the first electrode 31A and the second electrode 31B (through-hole wiring 31C).

[0034] The gate marks G31 shown in FIG. 4 are the remains of the resin injection portion when the hard substrate 31 is produced by injection molding.

[0035] 6 and 7 , the opening of the first through hole H31 is a circle that is line-symmetrical with respect to a center line LO that is perpendicular to the optical axis O of the camera unit and parallel to the long axis direction LA of the hard substrate 31. This ensures alignment accuracy for all of the multiple electrodes (first electrode 31A, second electrode 31B, through wiring 31C) that are arranged rotationally symmetrically around the optical axis O of the camera unit. The opening shape of the first through hole H31 may be elliptical, oval, or rectangular. Some of the electrodes may not be arranged rotationally symmetrically.

[0036] The gate marks G31 are also arranged symmetrically with respect to the center line LO, which makes it easy to inject resin into the hard substrate 31 during injection molding.

[0037] In manufacturing the hard substrate 31, for example, to form the first electrode 31A on the first surface F1, a laser is irradiated to match the shape of the first electrode 31A. Then, the laser is irradiated to a position on the second surface F2 corresponding to the position where the first electrode 31A is to be formed, and a through hole that becomes the through wiring 31C is formed. When the through hole is formed, the position where the first electrode 31A is to be formed cannot be seen from the second surface side. Therefore, there is a risk that the position of the through hole that becomes the through wiring 31C will be misaligned with the position of the first electrode 31A.

[0038] In an ultra-compact imaging module, it is not easy to form a large first electrode 31A while taking into consideration misalignment that may occur when forming the through-hole.

[0039] By using the first through hole H31 as a common alignment mark for the first surface F1 and the third surface F3 of the hard substrate 31, a through hole that becomes the through wiring 31C can be formed at a predetermined position on the second surface F2. For example, the opening of the first through hole H31 on the first surface F1 is used as the first alignment mark, and the opening of the first through hole H31 on the third surface F3 is used as the second alignment mark. The first alignment mark and the second alignment mark are accurately positioned so that they overlap when projected onto a virtual first surface F1A that is an extension of the first surface F1. Therefore, the position of the first electrode 31A relative to the first through hole H31 can be determined from the third surface F3.

[0040] After forming the through holes that will become the through wiring 31C, a laser is irradiated onto the region on the third surface F3 that will become the second electrode 31B and the region that will extend from the second electrode 31B and become the wiring 31D. Electroless plating is then performed to produce the hard substrate 31. The camera unit 32 and a signal cable are joined to the hard substrate 31, completing the imaging module 30.

[0041] It is preferable to form the alignment mark in a position close to the first electrode 31A. However, in the ultra-compact imaging module 30, there is no space for arranging a virtual opening of the same size as the opening of the first through-hole H31 in the area of ​​the second surface F2 where the second electrode 31B or the wiring 31D is not provided. For this reason, in the imaging module 30, the first through-hole H31 is formed in the second surface F2, which is inclined from the first surface F1.

[0042] However, the first through-hole H31 is formed perpendicular to the first surface F1 and the third surface F3. The first through-hole H31 has substantially the same size and shape whether viewed from the first surface F1 or the third surface F3, making accurate alignment easy. This makes the imaging module 30 easy to manufacture and ultra-compact.

[0043] 8, the through hole H131 is formed perpendicular to the second surface F2 and the fourth surface F4. Therefore, the shape of the through hole H131 viewed from above the first surface F1 is different from the shape of the through hole H131 viewed from above the third surface F3. Because the recognition position of the through hole H131 differs between the first surface F1 and the third surface F3, it is not easy to use it as an alignment mark.

[0044] In addition, after irradiating the area on the second surface F2 that will become the second electrode 31B with a laser, the first through hole H31 can be used as an alignment mark for positioning, and a through hole that will become the through wiring 31C can be formed by irradiating the laser from the first surface F1.

[0045] <Modification of First Embodiment> An imaging module A30 of this modification is similar to and has the same effects as the imaging module 30. For this reason, components having the same functions as those of the imaging module 30 are given the same reference numerals as those of the imaging module 30, and descriptions thereof will be omitted.

[0046] The rigid substrate A31 of the imaging module A30 of this modified example shown in FIG. 9 has a groove T31 perpendicular to the first surface F1, provided on the side surface FS from the third surface F3 to the fourth surface F4.

[0047] The groove T31 can be used as an alignment mark, similar to the first through-hole H31 of the imaging module 30.

[0048] The opening of the groove T31 may be semicircular, triangular, or rectangular as long as it has the same size and shape on the third face F3 and the fourth face F4. The rigid substrate A31 may have grooves on both side faces.

[0049] Second Embodiment An imaging module B30 of this embodiment is similar to and has the same effects as the imaging module 30. For this reason, components having the same functions as those of the imaging module 30 are given the same reference numerals as those of the imaging module 30, and descriptions thereof will be omitted.

[0050] As shown in Figures 10 and 11, the hard substrate B31 of the imaging module B30 has a fifth surface F5 parallel to the first surface F1 around the opening of the first through hole H31 on the third surface F3, and also has a sixth surface parallel to the first surface F1 around the opening of the first through hole H31 on the fourth surface F4.

[0051] In the hard substrate 31 of the first embodiment, the third surface F3 is inclined. Therefore, when viewed from a camera positioned perpendicular to the first surface F1, the leading end of the opening of the third surface F3 of the first through hole H31 is positioned lower than the trailing end. If the camera has a small depth of field, it may not be able to focus on the entire circumference of the opening, which could result in reduced alignment accuracy. In contrast, with the hard substrate B31, even if the camera has a small depth of field, it can focus on the entire circumference of the opening, resulting in high alignment accuracy.

[0052] Furthermore, when placing and fixing the hard substrate B31 on a jig (such as a tray) during the manufacturing process, the imaging module B30 can be accurately positioned on the jig using the fifth surface F5 and the sixth surface F6. For example, even if the first surface F1 cannot be fixed to the jig when inserting the camera unit 32 into the recess R31, the fifth surface F5 and the sixth surface F6 can be fixed to the jig.

[0053] The first distance H1, which is the distance between the fifth surface F5 and an imaginary first surface F1A formed by extending the first surface F1, is preferably longer than the second distance H2, which is the distance between the sixth surface F6 and an imaginary second surface F2A formed by extending the second surface F2. The fifth surface F5 and the sixth surface F6 of the hard substrate B31 can be more stably fixed to the jig. The fifth surface F5 and the sixth surface F6 may be provided around the openings at both ends of the groove T31 in FIG. 9.

[0054] The imaging module B30 is easier to manufacture than the imaging module 30.

[0055] It goes without saying that the endoscopes A10 and B10 having the imaging modules A30 and B30 have the same effects as the endoscope 10 and the imaging modules A30 and B30.

[0056] The ranges of the numerical values ​​described above are not limited to the ranges described above and can be increased or decreased as appropriate. Furthermore, the present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the scope of the present invention.

[0057] 2...Endoscope system 10, A10, B10...Endoscope 30, A30, B30...Imaging module 31, A31, B31...Hard substrate 31A...First electrode 31B...Second electrode 31C...Through-through wiring 31D...Wiring 32...Camera unit 32A...Imaging optical system 32B...Imaging element 32C...External electrode 39...Sealing resin G31...Gate mark H31...First through-hole R31...Recess T31...Groove θ1...First angle

Claims

1. An imaging module comprising: a camera unit having an external electrode on its underside; and a rigid substrate having a first surface on which the camera unit is mounted, a second surface opposite the first surface and parallel to the first surface, a third surface extending from the first surface at a first angle, and a fourth surface extending from the second surface and parallel to the third surface, wherein the rigid substrate has a first through-hole that penetrates between the third surface and the fourth surface and is perpendicular to the first surface, or a groove that is provided on a side surface of the rigid substrate from the third surface to the fourth surface and is perpendicular to the first surface.

2. The imaging module described in claim 1, characterized in that the hard substrate has: a first electrode provided on the first surface and joined to an external electrode of the camera unit; a second electrode provided on the second surface; a through wiring connecting the first electrode and the second electrode; and a wiring extending from the second electrode to the fourth surface.

3. The imaging module according to claim 2, wherein the first surface is a recessed bottom surface in which the camera unit is housed.

4. The imaging module described in claim 2, characterized in that the hard substrate is a molded circuit device made of a resin containing an electroless plating catalyst precursor, and the first electrode, the second electrode, the through wiring, and the wiring are electroless plated films.

5. The imaging module according to claim 4, wherein the opening of the first through hole is perpendicular to the optical axis of the camera unit and has a shape symmetrical with respect to a center line parallel to the long axis direction of the hard substrate.

6. The imaging module according to claim 5, wherein the hard substrate has a gate mark that is symmetrical with respect to the center line.

7. The imaging module according to claim 1, wherein the opening of the first through-hole is circular.

8. An imaging module as described in claim 2, characterized in that in the area of ​​the second surface where the second electrode or the wiring is not arranged, there is no space to arrange a virtual opening of the same size as the opening of the first through hole.

9. The imaging module described in claim 1, characterized in that the fifth surface around the openings at both ends of the first through-hole or groove on the third surface and the sixth surface around the openings at both ends of the first through-hole or groove on the fourth surface of the rigid substrate are parallel to the first surface.

10. The imaging module described in claim 9, characterized in that a first distance, which is the distance between an imaginary first surface that is an extension of the first surface and the fifth surface, is longer than a second distance, which is the distance between an imaginary second surface that is an extension of the second surface and the sixth surface.

11. An imaging module comprising: a camera unit having an external electrode on its underside; and a rigid substrate having a first surface on which the camera unit is mounted, a second surface opposite the first surface and parallel to the first surface, a third surface extending from the first surface at a first angle, and a fourth surface extending from the second surface and parallel to the third surface, wherein the rigid substrate has a first alignment mark on the third surface and a second alignment mark on the fourth surface, and the first alignment mark and the second alignment mark overlap when projected onto a virtual first surface which is a virtual extension of the first surface.

12. The imaging module described in claim 11, characterized in that the first alignment mark and the second alignment mark are openings at both ends of a first through-hole that penetrates the third surface and the fourth surface and is perpendicular to the first surface, or a groove that is provided on the side of the hard substrate from the third surface to the fourth surface and is perpendicular to the first surface.

13. An endoscope having an imaging module at the tip of an insertion section, the imaging module comprising: a camera unit having an external electrode on its underside; and a hard substrate having a first surface on which the camera unit is mounted, a second surface opposite to the first surface and parallel to the first surface, a third surface extending from the first surface at a first angle, and a fourth surface extending from the second surface and parallel to the third surface, wherein the hard substrate has a first through-hole that penetrates between the third surface and the fourth surface and is perpendicular to the first surface, or a groove that is provided on a side surface of the hard substrate from the third surface to the fourth surface and is perpendicular to the first surface.

Images