Camera unit, imaging module, and endoscope

Abstract

A camera unit, an imaging module, and an endoscope are provided. The camera unit includes an optical element, an image sensor, a second adhesive, a first resin, and a second resin. The image sensor includes a cover glass, a solid-state imaging element, and a first adhesive that bonds the cover glass and the solid-state imaging element. The second adhesive bonds the optical element and the cover glass. The first resin has light-blocking properties and covers at least a portion of a side surface of the optical element. The second resin covers a side surface of the first adhesive. The tensile elastic modulus of the second resin is smaller than that of the first resin.

Description

Technical Field

[0001] The present invention relates to a camera unit formed by bonding an optical element and an image sensor, an imaging module having the camera unit, and an endoscope having the imaging module. Background Art

[0002] Conventionally, an imaging module having a camera unit has been used for an endoscope. The camera unit includes, for example, an optical element and an image sensor. The image sensor is formed, for example, by bonding a protective glass and a solid-state imaging element using an adhesive.

[0003] For example, Japanese Unexamined Patent Application Publication No. 2012-189788 describes a camera module in which a camera module main body including a solid-state imaging device and WLO (Wafer Level Optics) is covered with a light-shielding resin and a first shield that blocks electromagnetic waves. The first shield is formed of a bottomed cylindrical metal. The camera module main body is accommodated in the first shield with a gap therebetween. The gap between the camera module main body and the first shield is filled with a light-shielding resin. Further, it is described in this publication that the light-shielding resin is composed of an upper layer resin (thermosetting resin) and a lower layer resin (ultraviolet curable resin). Summary of the Invention

[0004] A camera unit according to one aspect of the present invention includes: an image sensor having an optical element, a protective glass, a solid-state imaging element, and a first adhesive that bonds the protective glass and the solid-state imaging element; a second adhesive that bonds the optical element and the protective glass; a first resin that covers at least a part of a side surface of the optical element and has light-shielding properties; and a second resin that covers a side surface of the first adhesive, and a tensile elastic modulus of the second resin is smaller than a tensile elastic modulus of the first resin.

[0005] An imaging module according to one aspect of the present invention includes a camera unit, a three-dimensional wiring board, and a third resin. The camera unit includes: an optical element; an image sensor having a protective glass, a solid-state imaging element, and a first adhesive that bonds the protective glass and the solid-state imaging element; a second adhesive that bonds the optical element and the protective glass; a first resin that covers at least a part of a side surface of the optical element and has light-shielding properties; and a second resin that covers a side surface of the first adhesive, and a tensile elastic modulus of the second resin is smaller than a tensile elastic modulus of the first resin. The three-dimensional wiring board includes a chamber formed by a side wall and a bottom plate that connects the camera unit. The side wall surrounds the camera unit with a distance between the side wall and a side surface of the camera unit. The third resin is located between the side surface of the camera unit and the side wall and has light-shielding properties.

[0006] An endoscope according to one aspect of the present invention includes an imaging module and an insertion portion inserted into a subject. The imaging module includes a camera unit, a three-dimensional wiring board, and a third resin. The camera unit includes: an optical element; an image sensor including a protective glass, a solid-state imaging device, and a first adhesive bonding the protective glass to the solid-state imaging device; a second adhesive bonding the optical element to the protective glass; a first resin covering at least a part of a side surface of the optical element and having light-shielding properties; and a second resin covering a side surface of the first adhesive, wherein a tensile elastic modulus of the second resin is smaller than a tensile elastic modulus of the first resin. The three-dimensional wiring board includes a chamber formed by a side wall and a bottom plate connecting the camera unit, the side wall surrounds the camera unit with a distance between the side wall and a side surface of the camera unit, and the third resin is located between the side surface of the camera unit and the side wall and has light-shielding properties. The imaging module is provided at a front end portion of the insertion portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 FIG. 6 is a perspective view showing an appearance of an endoscope according to a first embodiment of the present invention.

[0008] Figure 2 FIG. 10 is a perspective view showing an outline of the imaging module according to the first embodiment.

[0009] Figure 3 FIG. 14 is a view showing an example of a cross section taken along line III-III of the imaging module according to the first embodiment. Figure 2 along line III-III

[0010] Figure 4 FIG. 20 is a view showing another example of a cross section taken along line III-III of the imaging module according to the first embodiment. Figure 2 along line III-III

[0011] Figure 5 FIG. 26 is a chart showing an example of physical properties of the first resin, the second resin, the third resin, and the first adhesive in the first embodiment.

[0012] Figure 6 FIG. 30 is a flowchart showing a manufacturing process of the camera unit in the first embodiment.

[0013] Figure 7 FIG. 34 is a chart for explaining the manufacturing process of the camera unit in the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Generally, in the manufacturing process, when connecting a camera unit to a wiring board of an imaging module, for example, solder bumps are reflowed and soldered at a high temperature in a reflow soldering furnace. In addition, an endoscope equipped with an imaging module is sometimes used at a high temperature, a low temperature, or a high humidity. When at least one of the temperature and humidity changes in the camera unit, the resin covering the side surface of the camera unit sometimes deforms, causing the image sensor to be stressed by the resin. As a result, cracks sometimes occur in the layer of the adhesive between the protective glass and the solid-state imaging element, starting from the outer periphery to the inside of the image sensor, and the cracks will reduce the image quality.

[0015] According to the embodiments described below, a camera unit, an imaging module, and an endoscope can be provided that can prevent cracks from occurring in the adhesive due to stress in the resin caused by a change in at least one of temperature and humidity.

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments described below.

[0017] In addition, in the description of the drawings, the same or corresponding elements are appropriately labeled with the same reference numerals. In addition, it should be noted that the drawings are schematic, and for the sake of simplicity of description, the length relationships between elements within one drawing, the ratio of the lengths of elements, the number of elements, etc. are sometimes different from the actual ones. Furthermore, between multiple drawings, there are sometimes also parts where the length relationships, ratios, numbers, etc. are different from each other.

[0018] [First Embodiment]

[0019] Figures 1 to 7 This shows the first embodiment of the present invention. Figure 1 It is a perspective view showing the appearance of the endoscope 1 of the first embodiment.

[0020] The endoscope 1 includes an insertion portion 2, an operation portion 3, and a universal cable 4. The endoscope 1 is configured as, for example, a side-view type electronic endoscope. In addition, the endoscope 1 can also be a direct-view type.

[0021] The insertion portion 2 is a portion configured to be inserted into a subject. The subject can be any subject such as a living organism such as a human or an animal, or a non-living organism such as a machine or a building. The insertion portion 2 includes a distal end portion 2a, a bending portion 2b, and a flexible tube portion 2c in order from the distal end side toward the proximal end side.

[0022] An imaging module 10 (see Figure 2 etc.), a lighting unit 6, a lifter 7, etc. are arranged in the distal end portion 2a. In addition, an example in which the endoscope 1 includes a lifter 7 is given here, but the endoscope 1 may not include a lifter 7.

[0023] The bending part 2b is a part that can bend in two directions or four directions, namely up, down, left, and right, for example.

[0024] The flexible tube part 2c is a tube part with flexibility. Additionally, here, an example is given where the endoscope 1 is a flexible endoscope having the flexible tube part 2c. However, the endoscope 1 can also be a rigid endoscope in a form where the part corresponding to the flexible tube part 2c is rigid.

[0025] The operation part 3 is disposed at the proximal end side of the insertion part 2. The operation part 3 is a part where the user operates the endoscope 1. The operation part 3 has a grip part 3a, a bending operation knob 3b, a plurality of operation buttons 3c, a treatment instrument insertion port 3d, and a treatment instrument lifting lever 3e.

[0026] The grip part 3a is a part where the user grips the endoscope 1 with the palm of the hand.

[0027] The treatment instrument insertion port 3d is an opening at the proximal end side of the treatment instrument channel. Treatment instruments such as forceps are inserted into the treatment instrument channel from the treatment instrument insertion port 3d. The distal end part of the treatment instrument is guided from the treatment instrument channel to the lifter 7 and protrudes into the subject's body. Various treatments are performed on the subject by the distal end part of the protruding treatment instrument.

[0028] The bending operation knob 3b is an operation device for operating the bending of the bending part 2b. For example, the thumb of the hand holding the grip part 3a is used to operate the bending operation knob 3b. When the bending operation knob 3b is operated, a bending operation wire (not shown) is pulled, and the bending part 2b bends.

[0029] When the bending part 2b bends, the direction of the distal end part 2a changes. Consequently, the imaging direction of the imaging module 10 and the irradiation direction of the illumination light from the illumination unit 6 change. Additionally, the bending part 2b also bends to improve the insertability of the insertion part 2 into the subject's body.

[0030] The plurality of operation buttons 3c include, for example, an air / water supply button, a suction button, and buttons related to shooting.

[0031] The air / water supply button is a button for the operation of supplying air and water to the observation window provided on the front end face of the imaging module 10 at the distal end part 2a. The observation window is cleaned by supplying liquid, and the liquid after cleaning is blown off by supplying air. The supply of air and water is carried out via the air / water supply channel.

[0032] The suction button is a button for the operation of sucking from the distal end part 2a into the subject's body. The suction from the subject's body is carried out, for example, via the treatment instrument channel that also serves as the suction channel. When the suction operation is performed, for example, liquid or mucosa is sucked from the subject's body.

[0033] The buttons related to shooting are, for example, button switches such as a freeze button for temporarily stopping the monitor screen and a release button for shooting a still image.

[0034] The disposal instrument lifting rod 3e is a rod for operating the lifting and inversion of the lifter 7 inside the front end portion 2a.

[0035] The general cable 4 extends from, for example, the side surface on the proximal end side of the operation unit 3. A connector 4a is provided at the extending end of the general cable 4. The connector 4a connects the endoscope 1 to an endoscope processor (video processor), a light source device, a suction pump, a water supply tank, and the like.

[0036] Figure 2 It is a perspective view showing an outline of the imaging module 10 of the first embodiment.

[0037] The imaging module 10 includes a three-dimensional wiring board 11 and a camera unit 20.

[0038] The three-dimensional wiring board 11 is configured as a three-dimensional (stereoscopic) molded circuit device (MID: Molded Interconnect Device). The three-dimensional wiring board 11 is, for example, formed with a plurality of conductor patterns, electrodes, etc. three-dimensionally on the curved surface, uneven surface, through holes, etc. of the injection-molded three-dimensional substrate.

[0039] The three-dimensional wiring board 11 includes an assembly part 12 and a convex part 13 protruding from the assembly part 12.

[0040] The convex part 13 is, for example, a bottomed square cylinder surrounded by rectangular side walls. Inside the convex part 13 is a chamber 13c for housing the camera unit 20.

[0041] Figure 3 It is a diagram showing an example of a cross-section along III-III of the imaging module 10 of the first embodiment. Figure 2 of III-III.

[0042] The camera unit 20 includes an optical element 21, an image sensor 22, a second adhesive 26, a first resin 28, and a second resin 29.

[0043] The specific structure of the optical element 21 is not shown in the figure. For example, it is a laminated lens including a plurality of optical lenses. The optical element 21 is, for example, configured as a WLO (Wafer Level Optics) manufactured using a semiconductor manufacturing process on a wafer. The optical element 21 forms an optical image of incident light.

[0044] Figure 4 It is a diagram showing another example of a cross-section along III-III of the imaging module 10 of the first embodiment. As Figure 2 of III-III. Figure 4As shown, the optical element 21 includes, for example, an optical aperture 21a for blocking unwanted light. The optical aperture 21a can also be configured, for example, as a light-shielding film having an opening in the center (a specific example is a chromium film or the like).

[0045] The image sensor 22 includes a protective glass 24, a solid-state imaging device 23, and a first adhesive 25.

[0046] The solid-state imaging device 23 has a plurality of pixels arranged on the imaging surface that perform photoelectric conversion on incident light to generate an electrical signal. The solid-state imaging device 23 converts the optical image of the subject imaged by the optical element 21 into a captured image signal composed of electrical signals of each pixel. Examples of the solid-state imaging device 23 are CCD (Charge-coupled device) and CMOS (Complementary Metal Oxide Semiconductor).

[0047] The solid-state imaging device 23 has a plurality of solder bumps 23a arranged on the surface opposite to the imaging surface, forming a ball grid array.

[0048] The first adhesive 25 is a transparent optical adhesive. The first adhesive 25 bonds the protective glass 24 to the imaging surface of the solid-state imaging device 23. The protective glass 24 and the solid-state imaging device 23 are bonded by the first adhesive 25 to form the image sensor 22.

[0049] The second adhesive 26 is a transparent optical adhesive. The second adhesive 26 bonds the optical element 21 to the protective glass 24. Thus, the optical element 21 is bonded to the image sensor 22.

[0050] The first resin 28 has light-shielding properties and covers at least a part of the side surface 21s of the optical element 21. Note that, as a method of imparting light-shielding properties to the resin, for example, a method of adding a black pigment such as carbon black to the resin can be used. However, the first resin 28 only needs to have light-shielding properties and is not limited to black.

[0051] In Figure 3 and Figure 4 In the example shown, the first resin 28 covers the entire circumference of the side surface 21s of the optical element 21 at a position slightly above (the incident light side) the second adhesive 26.

[0052] In the example shown where the optical aperture 21a is described, the first resin 28 covers the entire circumference of the side surface 21s of the optical element 21 in the range from the incident light side to between the optical aperture 21a and the second adhesive 26. Figure 4

[0053] ​The second resin 29 covers the side surface 25s of the first adhesive 25. The second resin 29 also covers at least a part of the side surface 26s of the second adhesive 26.

[0054] In Figure 3 and Figure 4 In the example shown, the second resin 29 covers the entire circumference of the side surface 23s of the solid-state imaging device 23, the entire circumference of the side surface 25s of the first adhesive 25, the entire circumference of the side surface 24s of the protective glass 24, the entire circumference of the side surface 26s of the second adhesive 26, and the entire circumference of the lower end side (the solid-state imaging device 23 side) of the side surface 21s of the optical element 21.

[0055] On the side surface 21s of the optical element 21, the first resin 28 is connected to the second resin 29, and the entire circumference of the side surface 21s is covered without a gap by the first resin 28 and the second resin 29.

[0056] The camera unit 20 is disposed in the chamber 13c of the convex member 13 of the three-dimensional wiring board 11.

[0057] The chamber 13c is formed by the side wall 13w and the bottom plate 13b, and is a space surrounded by the inner surface of the side wall 13w and the inner surface of the bottom plate 13b. The side wall 13w surrounds the camera unit 20 with a distance therebetween from the side surface 20s of the camera unit 20.

[0058] The camera unit 20 is connected to an electrode (not shown) through a solder bump 23a, and the electrode is provided on the inner surface of the bottom plate 13b of the chamber 13c of the three-dimensional wiring board 11. That is, the inner surface of the bottom plate 13b is the bottom surface of the chamber 13c connecting the camera unit 20.

[0059] The connection of the solder bump 23a is performed, for example, by reflow soldering. As is well known, reflow soldering is a process of heating a solder paste formed by mixing granular solder and a flux in a reflow oven, vaporizing the flux by heat, and joining the granular solders to perform soldering.

[0060] The imaging module 10 includes a third resin 31 filled between the camera unit 20 and the chamber 13c. The third resin 31 has a light-shielding property. The third resin 31 is located between the side surface 20s of the camera unit 20 and the inner surface of the side wall 13w, and between the bottom surface 20b of the camera unit 20 and the inner surface of the bottom plate 13b.

[0061] Figure 5 It is a graph showing an example of the physical properties of the first resin 28, the second resin 29, the third resin 31, and the first adhesive 25 in the first embodiment. In addition, in the Figure 5 graph, the symbol "-" indicates that a value has not been obtained.

[0062] In Figure 5In the example shown, the tensile elastic modulus of the first resin 28 is 6.4 (GPa), and the tensile elastic modulus of the second resin 29 is 4.1 (GPa). Therefore, the tensile elastic modulus of the second resin 29 is less than that of the first resin 28.

[0063] In addition, the tensile elastic modulus of the third resin 31 is 6.4 (GPa), which is the same as that of the first resin 28 in the Figure 5 example shown. The third resin 31 is made of, for example, the same material as the first resin 28. However, as long as it is a material with light-shielding properties, the third resin 31 can also be made of a material different from the first resin 28 (a different resin).

[0064] For example, if the third resin 31 is made of a material with a tensile elastic modulus equal to or higher than that of the first resin 28, the rigidity of the entire imaging module 10 can be improved.

[0065] In addition, if the third resin 31 is made of a material with a tensile elastic modulus equal to or lower than that of the second resin 29, the stress applied from the third resin 31 to the protective glass 24 when at least one of the temperature and humidity changes can be alleviated.

[0066] However, generally, when the temperature of the resin is below the glass transition temperature Tg (or at or below the glass transition temperature Tg), the movement of molecules is restricted and it becomes a hard glass state, and when the temperature is above the glass transition temperature Tg (or higher than the glass transition temperature Tg), the molecules become in an easily movable state and it becomes a soft rubber state.

[0067] Therefore, the linear expansion coefficient of the resin at a temperature below the glass transition temperature Tg (or at or below the glass transition temperature Tg) is denoted as α1, and the linear expansion coefficient of the resin at a temperature above the glass transition temperature Tg (or higher than the glass transition temperature Tg) is denoted as α2.

[0068] Regarding the linear expansion coefficient α1, the first resin 28 is 45 (ppm / °C), the second resin 29 is 67 (ppm / °C), the third resin 31 is 45 (ppm / °C), and the first adhesive 25 is 140 (ppm / °C).

[0069] Regarding the linear expansion coefficient α2, the first resin 28 is 130 (ppm / °C), the second resin 29 is 170 (ppm / °C), and the third resin 31 is 130 (ppm / °C).

[0070] Regarding the glass transition temperature Tg, the first resin 28 is 90 (°C), the second resin 29 is 3 (°C), the third resin 31 is 90 (°C), and the first adhesive 25 is 80 (°C).

[0071] First, consider the case of a temperature below 3 (°C) (or 3 (°C) and below). In the case of this temperature range, the linear expansion coefficients of the first resin 28, the second resin 29, the third resin 31, and the first adhesive 25 are all α1.

[0072] At this time, the difference (the absolute value of the difference, the same below) between the linear expansion coefficient α1 = 67 (ppm / °C) of the second resin 29 and the linear expansion coefficient α1 = 140 (ppm / °C) of the first adhesive 25 is 73 (ppm / °C).

[0073] In addition, the difference between the linear expansion coefficient α1 = 45 (ppm / °C) of the first resin 28 and the linear expansion coefficient α1 = 140 (ppm / °C) of the first adhesive 25 is 95 (ppm / °C).

[0074] Therefore, in the case of a temperature below 3 (°C) (or 3 (°C) and below), the difference of 73 (ppm / °C) between the linear expansion coefficient α1 of the second resin 29 and the linear expansion coefficient α1 of the first adhesive 25 is less than the difference of 95 (ppm / °C) between the linear expansion coefficient α1 of the first resin 28 and the linear expansion coefficient α1 of the first adhesive 25.

[0075] Next, consider the case of a temperature above 3 (°C) (or higher than 3 (°C)) and less than 80 (°C) (or 80 (°C) and below). In the case of this temperature range, the linear expansion coefficients of the first resin 28, the third resin 31, and the first adhesive 25 are α1, and the linear expansion coefficient of the second resin 29 is α2.

[0076] At this time, the difference between the linear expansion coefficient α2 = 170 (ppm / °C) of the second resin 29 and the linear expansion coefficient α1 = 140 (ppm / °C) of the first adhesive 25 is 30 (ppm / °C).

[0077] In addition, the difference between the linear expansion coefficient α1 = 45 (ppm / °C) of the first resin 28 and the linear expansion coefficient α1 = 140 (ppm / °C) of the first adhesive 25 is 95 (ppm / °C).

[0078] Therefore, in the case of a temperature above 3 (°C) (or higher than 3 (°C)) and less than 80 (°C) (or 80 (°C) and below), the difference of 30 (ppm / °C) between the linear expansion coefficient α2 of the second resin 29 and the linear expansion coefficient α1 of the first adhesive 25 is less than the difference of 95 (ppm / °C) between the linear expansion coefficient α1 of the first resin 28 and the linear expansion coefficient α1 of the first adhesive 25.

[0079] Thus, in a case where the temperature is less than 80 °C (or 80 °C or lower), a relationship holds in which the difference in the coefficient of linear expansion between the second resin 29 and the first adhesive 25 is less than the difference in the coefficient of linear expansion between the first resin 28 and the first adhesive 25.

[0080] As an example of a material satisfying the Figure 5 physical properties shown, the first resin 28 and the third resin 31 can be set as epoxy resins, the second resin 29 can be set as an acrylic resin, and the first adhesive 25 can be set as an epoxy resin.

[0081] However, this example is not limiting, and the first resin 28 and the third resin 31 can also use acrylic resins or silicone resins. The second resin 29 can also use epoxy resins or silicone resins. The first adhesive 25 can also use acrylic resins or silicone resins.

[0082] Figure 6 is a flowchart showing the manufacturing process (manufacturing method) of the camera unit 20 of the first embodiment. Figure 7 is a diagram for explaining the manufacturing process of the camera unit 20 in the first embodiment.

[0083] A naked camera unit 20 that has been manufactured by a semiconductor manufacturing process and to which the first resin 28 and the second resin 29 have not been attached is referred to as a wafer-level camera 20A. The wafer-level camera 20A includes an optical element 21, an image sensor 22, and a second adhesive 26.

[0084] Figure 6 and Figure 7 represents the process of manufacturing the camera unit 20 using the already manufactured wafer-level camera 20A.

[0085] When starting the Figure 6 processing shown, as shown in column A of Figure 7 , the wafer-level cameras 20A are arranged at intervals on the support substrate 41 (step S1). The support substrate 41 is made of, for example, a glass substrate. The incident light side of the wafer-level camera 20A is temporarily bonded to the support substrate 41 (upside down from the Figure 3 shown state).

[0086] The first resin 28 is supplied between the wafer-level cameras 20A arranged on the support substrate 41 (and outside the wafer-level cameras 20A arranged at both ends, the same applies hereinafter), and the first resin 28 is filled to the height described with reference to Figure 3 (in Figure 7 , a height slightly lower (incident light side) than the second adhesive 26) (step S2).

[0087] Next, the second resin 29 is supplied onto the first resin 28, and the second resin 29 is filled to the height described in the reference Figure 3 (the height covering the entire circumference of the side surface 23s of the solid-state imaging element 23 of the image sensor 22) (Step S3).

[0088] When the process of Step S3 is completed, as Figure 7 shown in column B of, the entire circumference of the side surface of the wafer-level camera 20A is covered with the first resin 28 and the second resin 29. In Figure 7 the state of column B of, a plurality of wafer-level cameras 20A are integrated by the first resin 28 and the second resin 29.

[0089] In this state, the support substrate 41 is removed from the integrated plurality of wafer-level cameras 20A and replaced with a dicing tape 42 (Step S4).

[0090] Cutting is performed so that a predetermined thickness of the first resin 28 and the second resin 29 remains on the side surface of each wafer-level camera 20A (Step S5). Thus, as Figure 7 shown in column C of, it becomes a state where a plurality of cut camera units 20 are adhered to the dicing tape 42.

[0091] After that, each camera unit 20 is peeled off from the dicing tape 42 and picked up (Step S6), and the Figure 6 shown process is completed.

[0092] As described above, the picked-up camera unit 20 is connected to the three-dimensional wiring board 11 by reflow soldering.

[0093] According to the first embodiment, the tensile elastic modulus of the second resin 29 covering the side surface 25s of the first adhesive 25 is smaller than the tensile elastic modulus of the first resin 28. Therefore, compared with the case where the side surface 25s is covered with the first resin 28, the stress applied by the second resin 29 to the first adhesive 25 due to changes in at least one of temperature and humidity can be reduced. As a result, it is possible to prevent cracks from occurring in the first adhesive 25 due to the stress generated by the resin covering the side surface of the wafer-level camera 20A due to changes in at least one of temperature and humidity.

[0094] Specifically, during the manufacturing process of connecting the camera unit 20 to the three-dimensional wiring board 11 by high-temperature reflow soldering, and when the endoscope 1 is used in an environment of high temperature, low temperature, or high humidity, the stress applied to the first adhesive 25 can be reduced, and cracks can be prevented from occurring in the first adhesive 25.

[0095] Moreover, the difference in the linear expansion coefficient between the second resin 29 and the first adhesive 25 is made smaller than the difference in the linear expansion coefficient between the first resin 28 and the first adhesive 25. Thereby, the difference in the change ratio of the lengths between the second resin 29 and the first adhesive 25 due to temperature change is smaller than the difference in the change ratio of the lengths between the first resin 28 and the first adhesive 25. Therefore, by covering the side surface 25s of the first adhesive 25 with the second resin 29, it is possible to prevent cracks from occurring in the first adhesive 25.

[0096] In addition, the second resin 29 also covers at least a part of the side surface 26s of the second adhesive 26. Therefore, during manufacturing and use, the stress applied to the second adhesive 26 can be reduced, and cracks can be prevented from occurring in the second adhesive 26.

[0097] Since the incident light side surface of the optical element 21 is covered with the light-shielding first resin 28, useless light can be prevented from entering the optical element 21.

[0098] According to the reference Figure 6 and Figure 7 the manufacturing method of the camera unit 20 described, multiple camera units 20 can be manufactured together. Therefore, there is no need to perform a process of sealing the singulated camera units 20 one by one with resin. Thereby, multiple camera units 20 can be manufactured by an automated and mechanized process, and thus the manufacturing cost can be reduced.

[0099] In addition, the present invention is not limited to the above-described embodiments themselves. The present invention can be embodied by deforming the constituent elements within the scope not departing from the gist of the invention at the implementation stage. In addition, a plurality of constituent elements disclosed in the above-described embodiments can be appropriately combined to form various inventive modes. For example, several constituent elements can be deleted from all the constituent elements disclosed in the embodiments. And, the constituent elements of different embodiments can be appropriately combined. In this way, of course, various deformations and applications can be made without departing from the gist of the invention.

Claims

1. A camera unit, characterized in that, Comprising: An optical element; An image sensor having a protective glass, a solid-state imaging element, and a first adhesive that bonds the protective glass to the solid-state imaging element; A second adhesive that bonds the optical element to the protective glass; A first resin that covers at least a part of the side surface of the optical element and has light-shielding properties; and A second resin that covers the side surface of the first adhesive, wherein the tensile elastic modulus of the second resin is less than that of the first resin.

2. The camera unit according to claim 1, wherein the second resin also covers the side surfaces of the protective glass and the solid-state imaging element.

3. The camera unit according to claim 2, wherein the second resin also covers at least a part of the side surface of the second adhesive.

4. The camera unit according to claim 1, wherein the difference between the coefficient of linear expansion of the second resin and that of the first adhesive is less than the difference between the coefficient of linear expansion of the first resin and that of the first adhesive.

5. The camera unit according to claim 1, wherein the optical element has an optical aperture, and the first resin covers the side surface of the optical element in the range from the incident light side to between the optical aperture and the second adhesive.

6. A camera module, characterized in that, Comprising a camera unit, a three-dimensional wiring board, and a third resin, wherein the camera unit comprises: An optical element; An image sensor having a protective glass, a solid-state imaging element, and a first adhesive that bonds the protective glass to the solid-state imaging element; A second adhesive that bonds the optical element to the protective glass; A first resin that covers at least a part of the side surface of the optical element and has light-shielding properties; and A second resin that covers the side surface of the first adhesive, wherein the tensile elastic modulus of the second resin is less than that of the first resin, the three-dimensional wiring board has a chamber formed by side walls and a bottom plate connecting the camera unit, and the side walls surround the camera unit with a distance between the side walls and the side surface of the camera unit, and the third resin is located between the side surface of the camera unit and the side walls and has light-shielding properties.

7. The imaging module according to claim 6, wherein the second resin also covers the side surfaces of the protective glass and the solid-state imaging element.

8. The imaging module according to claim 7, wherein the second resin also covers at least a part of the side surface of the second adhesive.

9. The imaging module according to claim 6, wherein the difference between the coefficient of linear expansion of the second resin and that of the first adhesive is less than the difference between the coefficient of linear expansion of the first resin and that of the first adhesive.

10. The imaging module according to claim 6, wherein the optical element has an optical aperture, and the first resin covers the side surface of the optical element in the range from the incident light side to between the optical aperture and the second adhesive.

11. The imaging module according to claim 6, wherein The tensile elastic modulus of the third resin is the same as that of the first resin.

12. The imaging module according to claim 11, wherein the third resin is the same material as the first resin.

13. The imaging module according to claim 12, wherein the first resin and the third resin are epoxy resins, and the second resin is an acrylic resin.

14. An endoscope, characterized in that, An endoscope includes an imaging module and an insertion portion inserted into a subject, the imaging module includes a camera unit, a three-dimensional wiring board, and a third resin, the camera unit includes: an optical element; an image sensor including a protective glass, a solid-state imaging element, and a first adhesive bonding the protective glass and the solid-state imaging element; a second adhesive bonding the optical element and the protective glass; a first resin covering at least a part of a side surface of the optical element and having light-shielding properties; and a second resin covering a side surface of the first adhesive, the tensile elastic modulus of the second resin is smaller than that of the first resin, the three-dimensional wiring board includes a chamber formed by a side wall and a bottom plate connecting the camera unit, the side wall surrounds the camera unit with a distance from a side surface of the camera unit, the third resin is located between the side surface of the camera unit and the side wall and has light-shielding properties, the imaging module is provided at a front end portion of the insertion portion.

15. The endoscope according to claim 14, wherein the second resin further covers side surfaces of the protective glass and the solid-state imaging element.

16. The endoscope according to claim 15, wherein the second resin further covers at least a part of a side surface of the second adhesive.

17. The endoscope according to claim 14, wherein the difference between the linear expansion coefficient of the second resin and that of the first adhesive is smaller than the difference between the linear expansion coefficient of the first resin and that of the first adhesive.

18. The endoscope according to claim 14, wherein the optical element includes an optical aperture, the first resin covers a range from an incident light side of the side surface of the optical element to a position between the optical aperture and the second adhesive.

19. The endoscope according to claim 14, wherein the tensile elastic modulus of the third resin is the same as that of the first resin.

20. The endoscope according to claim 19, wherein the third resin is the same material as the first resin.

21. A camera unit, characterized in that, An endoscope includes: an image sensor including a protective glass, a solid-state imaging element, and a first adhesive bonding the protective glass and the solid-state imaging element; an optical element bonded to the protective glass; a first resin covering at least a part of a side surface of the optical element; and a second resin covering a side surface of the first adhesive, the tensile elastic modulus of the second resin is smaller than that of the first resin.

22. The camera unit according to claim 21, wherein The protective glass and the optical element are bonded by a second adhesive, and the second resin also covers at least a part of the side surface of the second adhesive.

23. The camera unit according to claim 21, wherein the first resin has light-shielding properties.

24. An imaging module, characterized in that, Comprising: the camera unit according to any one of claims 21 to 23; a three-dimensional wiring board having a chamber formed by a side wall and a bottom plate, the side wall surrounding the camera unit with a distance between the side wall and the side surface of the camera unit, and the bottom plate being connected to the camera unit; and a third resin located between the side surface of the camera unit and the side wall, having light-shielding properties.

25. An endoscope comprising: the imaging module according to claim 24; and an insertion portion inserted into a subject, wherein the imaging module is provided at a front end portion of the insertion portion.

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