Imaging unit, endoscope, and method for manufacturing imaging unit

Abstract

Provided is an imaging unit capable of reducing surface scattered light and suppressing the occurrence of flare. 【Solution means】The imaging unit 1 includes a three-dimensional wiring board 10 having a recess with a side surface and a bottom surface, a camera module 30 disposed in the recess, a light-shielding resin 20 filled in a gap formed between the side surface and the bottom surface and the camera module 30, and the resin 20 has a transmittance of 0.5% or less and a light reflectance of 5% or less for light with a wavelength of 380 to 780 nm. When the azimuth angle from the incident surface is Φr and the polar angle is θr in the direction where the polar angle is θi of the incident direction, and the value of the bidirectional reflectance distribution function is BRDF(θi, Φr, θr), the value of the bidirectional reflectance distribution function is 0.1 or less of the incident light when θi is 45 to 75 degrees, Φr is -60 to 60 degrees, and θr is -85 to 85 degrees. (However, Φr ≠ 0 and θi ≠ θr)

Description

Technical Field

[0001] The present invention relates to an imaging unit including a light-shielding resin, an endoscope, and a method for manufacturing the imaging unit.

Background Art

[0002] Conventionally, an imaging unit is disposed at the tip of an endoscope. The imaging unit includes a camera unit in a recess provided in a three-dimensional wiring board. A light-shielding resin is filled between the recess and the camera unit for the purpose of improving bonding strength, waterproofness, and light-shielding properties.

[0003] For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2012-189788) discloses a camera module in which a light-shielding resin formed in black by adding a black pigment of carbon black is filled in a gap between a camera module body and a shield.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, even when a light-shielding resin is filled in the gap between the camera module body and the shield, surface scattered light cannot be reduced, and flare may occur.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide an imaging unit, an endoscope, and a method for manufacturing the imaging unit that can reduce surface scattered light and suppress the occurrence of flare.

Means for Solving the Problems

[0007] The imaging unit according to one aspect of the present invention includes a three-dimensional wiring board having a recess having a side surface and a bottom surface, a camera module disposed in the recess, and a light-emitting diode (LED) that is filled in a gap formed between the side surface, the bottom surface, and the camera module. Ta Resin; The camera module includes a laminated lens having a plurality of lenses and an imaging element, and the resin includes a first resin filled on the bottom side of the recess and a second resin filled on the opening side of the recess, the first resin having a greater dielectric breakdown resistance than the second resin.

[0008] In addition, an endoscope according to one aspect of the present invention has an imaging unit at a tip of an insertion portion that is inserted into a subject, and the imaging unit includes a three-dimensional wiring board having a recess having a side surface and a bottom surface, a camera module disposed in the recess, and a liquid crystal display (LCD) that fills a gap formed between the side surface, the bottom surface, and the camera module. Ta Resin; The device has an imaging unit at the tip of an insertion portion that is inserted into a subject, the imaging unit comprising: a three-dimensional wiring board with a recess having side and bottom surfaces; a camera module arranged in the recess; and resin filled in a gap formed between the side and bottom surfaces and the camera module, the camera module comprising a laminated lens having a plurality of lenses and an aperture, and an imaging element, the resin including a first resin filled on the bottom side of the recess and a second resin filled on the opening side of the recess, the first resin having a greater dielectric breakdown resistance value than the second resin.

[0009] Moreover, a manufacturing method for an imaging unit according to one embodiment of the present invention includes the steps of accommodating a camera module in a recess of a three-dimensional wiring board and connecting the wiring of the three-dimensional wiring board to the camera module via external electrodes; filling a gap between the recess of the three-dimensional wiring board and the camera module with a first resin from the bottom of the recess to the position of the aperture of the camera module; and filling a gap between the recess of the three-dimensional wiring board and the camera module with a second resin from the aperture to the outermost surface of the laminated lens of the camera module, wherein the first resin has a higher dielectric breakdown resistance value and a lower viscosity than the second resin. Effect of the Invention

[0010] According to the imaging unit, endoscope, and method for manufacturing an imaging unit of the present invention, it is possible to reduce surface scattered light and suppress the occurrence of flare. [Brief description of the drawings]

[0011] [Figure 1] 1 is an overall configuration diagram showing an example of the overall configuration of an endoscope according to a first embodiment. [Diagram 2] FIG. 1 is a perspective view showing a configuration of an imaging unit according to a first embodiment. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 2 is a diagram for explaining the relationship between incident light and reflected light. [Diagram 5] FIG. 11 is a cross-sectional view showing the configuration of an imaging unit according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, the embodiments will be described in detail with reference to the drawings. The drawings based on the embodiments are schematic, and 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. The direction in which light is incident is called "up."

[0013] (First embodiment) FIG. 1 is a diagram showing an example of the overall configuration of an endoscope according to a first embodiment. As shown in FIG. 1, an endoscope 100 includes an insertion section 101, an operation section 102, a universal cord 103, and an endoscope connector 104.

[0014] The insertion section 101, which has a long and thin tube shape, is inserted into a body cavity of a living body. The insertion section 101 includes a tip section 101A, a curved section 101B, and a flexible tube 101C, which are connected in this order from the tip side, and is flexible as a whole.

[0015] The distal end portion 101A includes an imaging unit 1 for acquiring image information of a subject, and further includes a treatment tool insertion channel, an illumination unit, and the like in addition to the imaging unit 1.

[0016] The bending portion 101B bends in the up, down, left and right directions in response to a rotation operation of a bending knob of an operation portion 102 for performing a bending operation.

[0017] The flexible tube 101C is a tubular member having flexibility that is passively flexible. A treatment tool insertion channel, various electric signal lines, a light guide fiber bundle, and the like are inserted inside the flexible tube 101C. The electric signal lines extend from the imaging unit 1 built into the distal end portion 101A, pass through the operation portion 102, and are extended to the universal cord 103. The light guide fiber bundle guides light from a light source device, which is an external device, to the distal end surface of the distal end portion 101A.

[0018] The operation unit 102 is connected to the base end of the insertion unit 101 and has a plurality of operation members, etc. The operation unit 102 is provided with a rotatable bending knob for bending the bending portion 101B, as well as a suction button, an air / water supply button, switches for various endoscopic functions, etc.

[0019] The universal cord 103 is a flexible tubular member extending from the operation unit 102. The endoscope connector 104 is a connection member for connecting the universal cord 103 to an external device such as a video processor and a light source device.

[0020] The endoscope may be a flexible endoscope having a flexible insertion portion or a rigid endoscope having a rigid insertion portion, and may be used for medical or industrial purposes.

[0021] Next, the configuration of the imaging unit 1 provided inside the tip portion 101A will be described. Fig. 2 is a perspective view showing the configuration of the imaging unit of the first embodiment. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.

[0022] As shown in FIG. 2 and FIG. 3, imaging unit 1 includes three-dimensional wiring board 10, resin 20, and camera module 30.

[0023] Three-dimensional wiring board 10 is a wiring board that is not a flat plate, for example, a molded interconnect device (MID), and has a bottomed recess (cavity) H10 with an opening on top surface 10SA. Camera module 30 is housed in recess H10.

[0024] The base material of three-dimensional wiring board 10 is a non-conductive resin, in particular, an engineering plastic that can be molded. The base material is, for example, PA (polyamide), PC (polycarbonate), LCP (liquid crystal polymer), PEEK (polyether ether ketone), nylon, PPA (polyphthalamide), ABS (acrylonitrile / butadiene / styrene), or a composite resin in which inorganic fillers are mixed with these resins.

[0025] The resin 20 is filled into the gap formed between the recess H10 and the camera module 30. More specifically, the resin 20 is filled into the gap formed between the side and bottom surface of the recess H10 and the camera module 30. The resin 20 is, for example, an epoxy resin to which black carbon slurry has been added, and has a light-shielding property. Note that the black material added to the resin 20 is not limited to carbon slurry, and may be carbon powder.

[0026] The resin 20 is preferably filled in a range of 95% to 100% of the total length D1 of the imaging unit 1 from the bottom surface of the recess H10.

[0027] The camera module 30 includes a stacked lens 31 having a plurality of lenses 33 and 34 and an aperture 35, and an image sensor 32. In the cross-sectional view, the plurality of lenses 33 and 34 are illustrated as flat plates. Also, the configuration of the optical system, that is, the configuration (thickness, shape), type, number, and stacking order of the plurality of lenses 33 and 34 and the aperture 35, can be modified in various ways according to the specifications.

[0028] A distance D2 from the outermost surface (front surface) of the laminated lens 31 to the diaphragm 35 in the direction along the optical axis O of the imaging unit 1 is preferably 30% to 60% of the overall length D1 of the imaging unit 1. In addition, an opening diameter W1 of the diaphragm 35 is preferably 6% to 9% of a maximum dimension W2 of the laminated lens 31 in a direction perpendicular to the optical axis O of the imaging unit 1.

[0029] Imaging element 32 has a light receiving portion formed of a CCD or the like. Imaging element 32 is connected to wiring 19 of three-dimensional wiring board 10 via external electrodes 36 such as solder balls. Imaging element 32 receives a drive signal from the outside and transmits an imaging signal to the outside via external electrodes 36 and wiring 19.

[0030] In addition, in the camera module 30, a semiconductor element for processing image signals may be stacked on the lower surface of the imaging element 32, and a cover glass may be disposed on the upper surface of the imaging element 32.

[0031] The resin 20 of the present embodiment has the following optical properties by containing 0.2 g to 0.4 g of carbon slurry per 100 g of epoxy resin, which allows the resin 20 to reduce surface scattered light and suppress flare.

[0032] FIG. 4 is a diagram for explaining the relationship between incident light and reflected light. 4, the polar angle of light (incident light) emitted from light source 41 to surface S1 of an object is denoted as θi. The azimuth angle of the light (reflected light) reflected by surface S1 from the incident surface S2 is denoted as Φr. The polar angle of the light (reflected light) reflected by surface S1 is denoted as θr.

[0033] Resin 20 contains 0.2 to 0.4 g of carbon slurry per 100 g of epoxy resin, and thus has a transmittance of 0.5% or less and a reflectance of 5% or less for light (visible light) having a wavelength of 380 to 780 nm.

[0034] Furthermore, the resin 20 has a characteristic that the value of the Bidirectional Reflectance Distribution Function (BRDF) of the reflected light detected by the detector 42 is 0.1 or less of that of the incident light when θi is 45 to 75 degrees, Φr is -60 to 60 degrees, and θr is -85 to 85 degrees, where Φr ≠ 0 and θi ≠ θr.

[0035] The polar angle θi of the incident direction is set to 45 to 75 degrees because light outside the range does not affect flare. For example, if the polar angle θi of the incident direction is 75 degrees or more, multiple reflections are required, and it is not detected as a flare. The azimuth angle Φr from the incident surface is set to -60 to 60 degrees because light outside the range is blocked by the aperture 35. The polar angle θr from the incident surface is set to -85 to 85 degrees because light outside the range does not affect flare. The reason for Φr≠0 and θi≠θr is to exclude regular reflection.

[0036] In the imaging unit 1 of the present embodiment, resin 20 having the above optical properties is filled between three-dimensional wiring board 10 and camera module 30. As a result, imaging unit 1 of the present embodiment can reduce surface scattered light and suppress flare compared to the case where light-shielding resin is simply filled.

[0037] Second Embodiment Next, a second embodiment will be described. Fig. 5 is a cross-sectional view showing the configuration of an imaging unit according to the second embodiment. In Fig. 5, the same components as those in Fig. 3 are given the same reference numerals and the description thereof will be omitted.

[0038] As shown in FIG. 5, in imaging unit 1A, a gap formed between recess H10 of circuit board 10 and camera module 30 is filled with first resin 20A and second resin 20B.

[0039] The first resin 20A fills from the bottom surface of the recess H10 to the restrictor 35 or to a surface below the restrictor 35. The first resin 20A is a resin having a higher dielectric breakdown resistance value and a lower viscosity than the second resin 20B.

[0040] The second resin 20B has a breakdown voltage per 100 μm of less than 15 kV. On the other hand, the first resin 20A has a breakdown voltage per 100 μm of 15 kV or more. In this way, by increasing the breakdown resistance value of the first resin 20A filled in the gaps between the multiple external electrodes 36, it is possible to improve electrostatic resistance.

[0041] Moreover, by making the viscosity of the first resin 20A smaller than that of the second resin 20B, the first resin 20A can be easily filled into the gaps between the multiple external electrodes 36 disposed between the recess H10 and the bottom surface of the camera unit 30.

[0042] The second resin 20B is the same resin as the resin 20 in the first embodiment, that is, 0.2 to 0.4 g of carbon slurry is contained per 100 g of epoxy resin. The second resin 20B is filled from the aperture 35 or the lower surface side of the aperture 35 to the outermost surface of the laminated lens 31, more specifically, in a range of 95% to 100% of the total length D1 of the imaging unit 1. Since the second resin 20B is the same resin as the resin 20 in the first embodiment, it is possible to reduce surface scattered light and suppress flare.

[0043] In imaging unit 1A of the present embodiment, camera module 30 is housed in recess H10 of three-dimensional wiring board 10, and wiring 19 of three-dimensional wiring board 10 and camera module 30 are connected by external electrodes .

[0044] Thereafter, first resin 20A is filled into the gap between recess H10 of three-dimensional wiring board 10 and camera module 30 from the bottom surface of recess H10 to the position of aperture 35 (or below aperture 35).

[0045] Finally, the imaging unit 1A can be assembled by filling the gap between the recess H10 of the three-dimensional wiring board 10 and the camera module 30 with the second resin 20B from the aperture 35 (or the lower side of the aperture 35) to the outermost surface of the laminated lens 31.

[0046] The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0047] 1, 1A...imaging unit, 10...three-dimensional wiring board, 20...resin, 20A...first resin, 20B...second resin, 30...camera module, 31...laminated lens, 32...imaging element, 33, 34...lens, 35...diaphragm, 36...external electrode, 41...light source, 42...detector, 100...endoscope, 101...insertion portion, 101A...tip portion, 101B...bending portion, 101C...flexible tube, 102...operation portion, 103...universal cord, 104...endoscope connector.

Claims

1. A three-dimensional wiring board having a recess having a side surface and a bottom surface; A camera module disposed in the recess; a resin filled in a gap formed between the side surface and the bottom surface and the camera module, The camera module includes a laminated lens having a plurality of lenses and an imaging element, the resin includes a first resin filled on a bottom side of the recess and a second resin filled on an opening side of the recess, The first resin has a higher dielectric breakdown resistance than the second resin.

2. The laminated lens has an aperture, the first resin is filled from a bottom surface of the recess to a position where the restriction is provided or to a lower surface side of the restriction, 2. The imaging unit according to claim 1, wherein the second resin is filled from a position where the diaphragm is provided or from a lower surface side of the diaphragm to a position of the outermost surface of the laminated lens.

3. The imaging unit is provided at the tip of an insertion part that is inserted into a subject. The imaging unit includes: A three-dimensional wiring board having a recess having a side surface and a bottom surface; A camera module disposed in the recess; a resin filled in a gap formed between the side surface and the bottom surface and the camera module, the camera module includes a laminated lens having a plurality of lenses and an aperture, and an image sensor; the resin includes a first resin filled on a bottom side of the recess and a second resin filled on an opening side of the recess, The endoscope according to claim 1, wherein the first resin has a higher dielectric breakdown resistance than the second resin.

4. The laminated lens has an aperture, the first resin is filled from a bottom surface of the recess to a position where the restriction is provided or to a lower surface side of the restriction, 4. The endoscope according to claim 3, wherein the second resin is filled from a position where the diaphragm is provided or from a lower surface side of the diaphragm to a position of the outermost surface of the laminated lens.

5. a step of accommodating a camera module in a recess of the three-dimensional wiring board and connecting the wiring of the three-dimensional wiring board and the camera module by an external electrode; filling a gap between the recess of the three-dimensional wiring board and the camera module on a bottom side of the recess with a first resin; filling a gap between the recess of the three-dimensional wiring board and the camera module on an opening side of the recess with a second resin; wherein the first resin has a higher dielectric breakdown resistance than the second resin.

6. The step of filling the recess with the first resin includes filling the recess with the first resin from a bottom surface of the recess to a position of an aperture of the camera module or to a lower surface side of the aperture; 6. The method for manufacturing an imaging unit according to claim 5, wherein the step of filling the second resin includes filling the second resin from the position of the aperture or below the aperture to the outermost surface of the laminated lens of the camera module.

Images