Camera unit, imaging module, and endoscope

Abstract

To provide a camera unit or the like capable of preventing cracks from occurring in an adhesive due to stress of a resin caused by a change in at least one of temperature and humidity.SOLUTION: The camera unit 20 includes an image sensor 22 including an optical device 21, a cover glass 24, a solid-state image sensing device 23, and a first adhesive 25 located between the cover glass 24 and the solid-state image sensing device 23 and bonding the cover glass 24 and the solid-state image sensing device 23, a second adhesive 26 bonding the optical device 21 and the cover glass 24, a first adhesive 28 covering at least a part of an 21s of a side surface of the optical device 21, and a second adhesive 29 covering a side surface of the first adhesive 26. The tensile elastic modulus of the second resin 29 is smaller than that of the first resin 28.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

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

[0003] For example, Japanese Patent Application Laid-Open No. 2012-189788 describes a camera module in which a camera module body including a solid-state imaging device and a 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 body is accommodated in the first shield with a gap. The light-shielding resin is filled in the gap between the camera module body and the first shield. Further, the publication describes that the light-shielding resin is composed of an upper layer resin (thermosetting resin) and a lower layer resin (ultraviolet curable resin).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, during the manufacturing process, when connecting the camera unit to the wiring board of the imaging module, soldering is performed by reflowing solder bumps at high temperatures in a reflow oven, for example. Furthermore, endoscopes equipped with imaging modules may be used under high temperatures, low temperatures, or high humidity conditions. If at least one of the temperature and humidity changes in the camera unit, deformation may occur in the resin covering the sides of the camera unit, and the image sensor may be subjected to stress from the resin. As a result, cracks may form in the adhesive layer between the cover glass and the solid-state image sensor, extending from the outer edge to the inside of the image sensor, and these cracks may degrade the image quality.

[0006] The present invention has been made in view of the above circumstances, and aims to provide a camera unit, an imaging module, and an endoscope that can prevent cracks from occurring in the adhesive due to stress on the resin caused by changes in at least one of temperature and humidity. [Means for solving the problem]

[0007] A camera unit according to one aspect of the present invention includes an image sensor comprising: an optical element; a cover glass; a solid-state image sensor; and a first adhesive positioned between the cover glass and the solid-state image sensor and bonding the cover glass and the solid-state image sensor; A second adhesive for bonding the optical element and the cover glass, A first resin covering at least a portion of the side surface of the optical element, At least solid-state image sensors It comprises a second resin covering the side, The tensile modulus of the second resin is smaller than that of the first resin. The first resin has light-shielding properties, The second resin is not covered by the first resin, and does not cover the first resin. The interface between the first resin and the second resin is located between the position between the incident surface and the exit surface of the optical element and the position of the interface between the cover glass and the first adhesive.

[0008] An imaging module according to one aspect of the present invention comprises an image sensor comprising: an optical element; a cover glass; a solid-state image sensor; a first adhesive positioned between the cover glass and the solid-state image sensor and bonding the cover glass and the solid-state image sensor; a second adhesive bonding the optical element and the cover glass; a first resin covering at least a portion of the side surface of the optical element; and a second resin covering the side surface of the first adhesive, wherein the tensile modulus of the second resin is smaller than that of the first resin. The first resin has light-shielding properties, the second resin is not covered by the first resin and does not cover the first resin, and the interface between the first resin and the second resin is located between the interface between the cover glass and the first adhesive, from the position between the incident surface and the exit surface of the optical element. Camera unit and A side wall surrounds the camera unit, having a distance from the side surface of the camera unit, A base to which the camera unit is connected, and a three-dimensional wiring board having a cavity formed therein, The device comprises a third resin located between the side surface of the camera unit and the side wall.

[0009] An endoscope according to one aspect of the present invention includes an image sensor comprising: an optical element; a cover glass; a solid-state image sensor; and a first adhesive positioned between the cover glass and the solid-state image sensor and bonding the cover glass and the solid-state image sensor; A second adhesive for bonding the optical element and the cover glass, A first resin covering at least a portion of the side surface of the optical element, The present invention comprises a second resin covering the side surface of the first adhesive, The tensile modulus of the second resin is smaller than that of the first resin. The first resin has light-shielding properties, The second resin is not covered by the first resin, and does not cover the first resin. The interface between the first resin and the second resin is located between the position between the incident surface and the exit surface of the optical element and the position of the interface between the cover glass and the first adhesive. Camera unit and A three-dimensional wiring board comprising a cavity formed by a side wall that surrounds the camera unit with a distance between it and the side surface of the camera unit, and a base to which the camera unit is connected, The imaging module comprises a third resin located between the side surface of the camera unit and the side wall, and an insertion portion that is inserted into a subject, with the imaging module provided at the tip of the insertion portion.

Advantages of the Invention

[0010] According to the camera unit, imaging module, and endoscope of the present invention, it is possible to prevent cracks from occurring in the adhesive due to the stress of the resin caused by changes in at least one of temperature and humidity.

Brief Description of the Drawings

[0011] [Figure 1] It is a perspective view showing the appearance of the endoscope of the first embodiment of the present invention. [Figure 2] It is a perspective view showing an overview of the imaging module of the first embodiment. [Figure 3] It is a view showing an example of a cross-section taken along line III-III of FIG. 2 of the imaging module of the first embodiment. [Figure 4] It is a view showing another example of a cross-section taken along line III-III of FIG. 2 of the imaging module of the first embodiment. [Figure 5] It is a chart showing an example of the physical properties of the first resin, second resin, third resin, and first adhesive in the first embodiment. [Figure 6] It is a flowchart showing the manufacturing process of the camera unit in the first embodiment. [Figure 7] It is a chart for explaining the manufacturing process of the camera unit in the first embodiment. [Figure 8] It is a view showing an example of a cross-section of the imaging module of a modified example. [Figure 9] It is a cross-sectional view for explaining the boundary between the first resin and the second resin of the imaging module of a modified example.

Modes for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited by the embodiments described below.

[0013] In the drawings, identical or corresponding elements are appropriately denoted by the same reference numeral. Furthermore, it should be noted that drawings are schematic representations, and the relationships between the lengths of elements, the ratios of their lengths, and the quantities of each element within a single drawing may differ from reality for the sake of simplicity. Additionally, there may be differences in the relationships between lengths, ratios, and quantities between multiple drawings. [First Embodiment]

[0014] Figures 1 to 7 show a first embodiment of the present invention. Figure 1 is a perspective view showing the external appearance of the endoscope 1 of the first embodiment.

[0015] The endoscope 1 comprises an insertion section 2, an operating section 3, and a universal cable 4. The endoscope 1 is configured, for example, as a side-viewing type electronic endoscope. However, the endoscope 1 may also be a straight-viewing type.

[0016] The insertion portion 2 is a part configured to be inserted into the subject. The subject may be a living organism such as a person or animal, or a non-living organism such as a machine or building. The insertion portion 2 comprises, in order from the tip end to the proximal end, a tip portion 2a, a curved portion 2b, and a flexible tube portion 2c.

[0017] The tip section 2a houses an imaging module 10 (see Figure 2, etc.), a lighting unit 6, a lifting platform 7, and other components. While this example shows the endoscope 1 equipped with a lifting platform 7, it is not required to have one.

[0018] The curved portion 2b is, for example, a part that can bend in two directions, or in four directions: up, down, left, and right.

[0019] The flexible tube section 2c is a tubular section that is flexible. Here, we give an example where the endoscope 1 is a flexible endoscope having a flexible tube section 2c. However, the endoscope 1 may also be a rigid endoscope with a rigid form in the part corresponding to the flexible tube section 2c.

[0020] The operating section 3 is located on the proximal end side of the insertion section 2. The operating section 3 is the part used by the user to operate the endoscope 1. The operating section 3 comprises a gripping section 3a, a bending operation knob 3b, a plurality of operating buttons 3c, a treatment instrument insertion port 3d, and a treatment instrument raising lever 3e.

[0021] The gripping section 3a is the part where the user grasps the endoscope 1 with their palm.

[0022] The instrument insertion port 3d is the proximal opening of the instrument channel. Instruments such as forceps are inserted into the instrument channel through the instrument insertion port 3d. The tip of the instrument is guided from the instrument channel to the lifting platform 7 and protrudes into the subject. Various procedures are performed on the subject using the protruding tip of the instrument.

[0023] The bending operation knob 3b is an operating device for controlling the bending of the bending section 2b. The bending operation knob 3b is operated, for example, with the thumb of the hand that is gripping the gripping section 3a. When the bending operation knob 3b is operated, a bending operation wire (not shown) is pulled, and the bending section 2b is bent.

[0024] When the curved portion 2b is curved, the direction of the tip portion 2a changes. This changes the imaging direction by the imaging module 10 and the direction of illumination light from the illumination unit 6. The curved portion 2b is also curved to improve the insertability of the insertion portion 2 within the subject.

[0025] The multiple operation buttons 3c include, for example, an air supply / water supply button, a suction button, and buttons related to imaging.

[0026] The air / water supply button is located at the tip 2a and is used to supply air and water to the observation window provided on the tip surface of the imaging module 10. The observation window is cleaned by the supply of liquid, and the liquid is blown away by the supply of air. Air and water are supplied via the air / water supply channel.

[0027] The suction button is used to perform an operation to aspirate from the subject through the tip 2a. Suction from the subject is performed, for example, via the instrument channel, which also serves as the suction channel. When the suction operation is performed, liquids or mucous membranes, for example, are aspirated from the subject.

[0028] Buttons related to image capture include, for example, a freeze button to pause the monitor screen and a release button to capture a still image.

[0029] The treatment instrument raising lever 3e is a lever for operating the raising and lowering of the raising platform 7 located within the tip portion 2a.

[0030] The universal cable 4 extends from, for example, the base end side of the operating unit 3. A connector 4a is provided at the extended end of the universal cable 4. The connector 4a connects the endoscope 1 to an endoscope processor (video processor), a light source device, a suction pump, and a water supply tank, etc.

[0031] Figure 2 is a perspective view showing an overview of the imaging module 10 of the first embodiment.

[0032] The imaging module 10 includes a three-dimensional wiring board 11 and a camera unit 20.

[0033] The three-dimensional wiring board 11 is configured as a three-dimensional (three-dimensional) molded interconnect device (MID). The three-dimensional wiring board 11 has multiple conductor patterns, electrodes, etc., formed three-dimensionally on curved surfaces, uneven surfaces, and through holes of, for example, an injection-molded three-dimensional substrate.

[0034] The three-dimensional wiring board 11 comprises an assembly member 12 and a protruding member 13 that extends from the assembly member 12.

[0035] The convex member 13 is, for example, a bottomed rectangular tube surrounded by rectangular side walls. Inside the convex member 13 is a cavity 13c in which the camera unit 20 is housed.

[0036] Figure 3 shows an example of the III-III cross-section of the imaging module 10 of the first embodiment in Figure 2.

[0037] The camera unit 20 comprises an optical element 21, an image sensor 22, a second adhesive 26, a first resin 28, and a second resin 29.

[0038] The optical element 21, although its specific configuration is not shown in the diagram, is, for example, a stacked lens containing multiple optical lenses. The optical element 21 is configured, for example, as a WLO (Wafer Level Optics) manufactured on a wafer using a semiconductor manufacturing process. The optical element 21 forms an optical image of the incident light.

[0039] Figure 4 shows another example of the imaging module 10 of the first embodiment, in the III-III cross-section of Figure 2. As shown in Figure 4, the optical element 21 includes, for example, an optical aperture 21a for cutting out unwanted light. The optical aperture 21a may be configured as, for example, a light-shielding film (specifically, a chromium film) having an opening in the center.

[0040] The image sensor 22 comprises a cover glass 24, a solid-state image sensor 23, and a first adhesive 25.

[0041] The solid-state image sensor 23 has multiple pixels arranged on its imaging surface that convert incident light into electrical signals through photoelectric conversion. The solid-state image sensor 23 converts the optical image of the subject formed by the optical element 21 into an imaging signal composed of electrical signals for each pixel. Examples of solid-state image sensors 23 include CCD (Charge-coupled device) and CMOS (Complementary Metal Oxide Semiconductor).

[0042] The solid-state image sensor 23 has multiple solder bumps 23a arranged on the side opposite to the imaging surface, forming a ball grid array.

[0043] The first adhesive 25 is a transparent optical adhesive. The first adhesive 25 is located between the cover glass 24 and the solid-state image sensor 23. The first adhesive 25 is in contact with the cover glass 24 and the solid-state image sensor 23. The first adhesive 25 adheres the cover glass 24 to the imaging surface of the solid-state image sensor 23. The first adhesive 25 is provided in all areas between the cover glass 24 and the imaging surface of the solid-state image sensor 23. The cover glass 24 and the solid-state image sensor 23 are bonded together by the first adhesive 25 to form the image sensor 22.

[0044] The second adhesive 26 is a transparent optical adhesive. The second adhesive 26 adheres the optical element 21 to the cover glass 24. This adheres the optical element 21 to the image sensor 22.

[0045] The first resin 28 has light-shielding properties and covers at least a portion of the side surface 21s of the optical element 21. As a method for giving the resin light-shielding properties, for example, a black pigment such as carbon black may be added to the resin. However, the first resin 28 is not limited to black as long as it has light-shielding properties. It is also possible to use a resin that does not have light-shielding properties for the first resin 28.

[0046] In the examples shown in Figures 3 and 4, the first resin 28 covers the entire circumference of the side surface 21s of the optical element 21, up to slightly above the second adhesive 26 (towards the incident light side). In the optical element 21, the surface that is bonded to the second adhesive 26 is the exit surface, and the surface opposite the exit surface is the incident surface.

[0047] In the example shown in Figure 4, which illustrates the optical aperture 21a, the first resin 28 covers the entire circumference of the side surface 21s of the optical element 21, from the incident light side to the space between the optical aperture 21a and the second adhesive 26.

[0048] The second resin 29 covers the side surface 25s of the first adhesive 25. The second resin 29 further covers at least a portion of the side surface 26s of the second adhesive 26. The second resin 29 is in contact with the side surface of the first adhesive 25.

[0049] In the examples shown in Figures 3 and 4, the second resin 29 covers the entire circumference of the side surface 23s of the solid-state image sensor 23, the entire circumference of the side surface 25s of the first adhesive 25, the entire circumference of the side surface 24s of the cover glass 24, the entire circumference of the side surface 26s of the second adhesive 26, and the entire circumference of the lower end side (solid-state image sensor 23 side) of the optical element 21.

[0050] On the side surface 21s of the optical element 21, the first resin 28 and the second resin 29 are connected, and the entire circumference of the side surface 21s is covered without any gaps by the first resin 28 and the second resin 29.

[0051] The camera unit 20 is placed inside the cavity 13c of the protruding member 13 of the three-dimensional wiring board 11.

[0052] The cavity 13c is formed by the side wall 13w and the base floor 13b, and is a space enclosed by the inner surfaces of the side wall 13w and the base floor 13b. The side wall 13w surrounds the camera unit 20 with a distance between it and the side surface 20s of the camera unit 20.

[0053] The camera unit 20 is connected by solder bumps 23a to electrodes (not shown) provided on the inner surface of the base 13b of the cavity 13c of the three-dimensional wiring board 11. In other words, the inner surface of the base 13b is the bottom surface of the cavity 13c to which the camera unit 20 is connected.

[0054] The solder bumps 23a are joined, for example, by reflow soldering. Reflow soldering, as is well known, is a process in which a solder paste, which is a mixture of granular solder and flux, is heated in a reflow oven to vaporize the flux with heat, joining the granular solder together and thus soldering them.

[0055] The imaging module 10 includes a third resin 31 that is filled between the camera unit 20 and the cavity 13c. The third resin 31 has light-shielding properties. 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 base 13b. It is also possible to use a resin that does not have light-shielding properties for the third resin 31.

[0056] Figure 5 is a chart 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 the chart of Figure 5, the symbol "-" indicates that a value has not been obtained.

[0057] In the example shown in Figure 5, the tensile modulus of the first resin 28 is 6.4 (Gpa), and the tensile modulus of the second resin 29 is 4.1 (Gpa). Therefore, the tensile modulus of the second resin 29 is smaller than that of the first resin 28.

[0058] Furthermore, the tensile modulus of the third resin 31 is 6.4 (Gpa), which is the same as the tensile modulus of the first resin 28 in the example shown in Figure 5. The third resin 31 is made of the same material as the first resin 28, for example. However, the third resin 31 may be made of a different material (a different resin) than the first resin 28, as long as it is a light-shielding material.

[0059] For example, if the third resin 31 is made of a material having a tensile modulus of elasticity greater than or equal to that of the first resin 28, the overall rigidity of the imaging module 10 can be increased.

[0060] Furthermore, if the third resin 31 is made of a material having a tensile modulus less than or equal to that of the second resin 29, the stress applied from the third resin 31 to the cover glass 24 when at least one of the temperature and humidity changes can be relieved.

[0061] Incidentally, resins generally become a hard, glassy state when the molecular motion is restricted at temperatures below the glass transition temperature (Tg) (or less than or equal to the glass transition temperature), and become a soft, rubbery state when the molecular motion becomes more flexible at temperatures above the glass transition temperature (or higher than the glass transition temperature).

[0062] Therefore, the coefficient of linear expansion of the resin at temperatures below the glass transition temperature Tg (or less than or equal to the glass transition temperature Tg) is denoted as α1, and the coefficient of linear expansion of the resin at temperatures above the glass transition temperature Tg (or higher than the glass transition temperature Tg) is denoted as α2.

[0063] The coefficient of linear expansion α1 is 45 ppm / °C for the first resin 28, 67 ppm / °C for the second resin 29, 45 ppm / °C for the third resin 31, and 140 ppm / °C for the first adhesive 25.

[0064] The coefficient of linear expansion α2 is 130 ppm / °C for the first resin 28, 170 ppm / °C for the second resin 29, and 130 ppm / °C for the third resin 31.

[0065] The glass transition temperatures (Tg) are 90°C for the first resin 28, 3°C for the second resin 29, 90°C for the third resin 31, and 80°C for the first adhesive 25.

[0066] First, let's consider the case where the temperature is less than (or less than) 3°C. In this temperature range, the coefficient of linear expansion of the first resin 28, the second resin 29, the third resin 31, and the first adhesive 25 is all α1.

[0067] At this time, the difference (absolute value of the difference, the same applies hereafter) 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).

[0068] Furthermore, 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).

[0069] Therefore, at temperatures below 3°C (or less), 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 smaller 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.

[0070] Next, consider the case where the temperature is 3°C or higher and less than 80°C. In this temperature range, the coefficients of linear expansion of the first resin 28, the third resin 31, and the first adhesive 25 are α1, and the coefficient of linear expansion of the second resin 29 is α2.

[0071] 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).

[0072] Furthermore, 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).

[0073] Therefore, at temperatures of 3°C or higher and less than 80°C, 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 smaller 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.

[0074] Thus, at temperatures below 80°C (or below), the difference between the linear expansion coefficient of the second resin 29 and the linear expansion coefficient of the first adhesive 25 is smaller than the difference between the linear expansion coefficient of the first resin 28 and the linear expansion coefficient of the first adhesive 25.

[0075] As an example of a material that satisfies the physical properties shown in Figure 5, the first resin 28 and the third resin 31 may be epoxy resins, the second resin 29 may be an acrylic resin, and the first adhesive 25 may be an epoxy resin.

[0076] However, the first resin 28 and the third resin 31 may be acrylic resin or silicone resin, although this example is not limited to this. The second resin 29 may be epoxy resin or silicone resin. The first adhesive 25 may be acrylic resin or silicone resin.

[0077] Figure 6 is a flowchart showing the manufacturing process (manufacturing method) of the camera unit 20 in the first embodiment. Figure 7 is a diagram illustrating the manufacturing process of the camera unit 20 in the first embodiment.

[0078] A naked camera unit 20, manufactured by a semiconductor manufacturing process and without the first resin 28 and second resin 29 applied, will be 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.

[0079] Figures 6 and 7 show the process of manufacturing the camera unit 20 using the already manufactured wafer-level camera 20A.

[0080] When the process shown in Figure 6 is started, the wafer-level cameras 20A are arranged on the support substrate 41 at intervals as shown in column A of Figure 7 (step S1). The support substrate 41 is made of, for example, a glass substrate. The wafer-level camera 20A is temporarily attached to the support substrate 41 with the incident light side facing it (the orientation is reversed compared to the state shown in Figure 3).

[0081] 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 located at both ends, and so on) and filled to the height described with reference to Figure 3 (in Figure 7, the height slightly below the second adhesive 26 (incident light side)) (step S2).

[0082] Furthermore, the second resin 29 is supplied on top of the first resin 28 and filled to the height described with reference to Figure 3 (a height that covers the entire circumference of the side surface 23s of the solid-state image sensor 23 of the image sensor 22) (step S3).

[0083] After completing step S3, 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, as shown in column B of Figure 7. In the state shown in column B of Figure 7, multiple wafer-level cameras 20A are integrated by the first resin 28 and the second resin 29.

[0084] In this state, the support substrates 41 are removed from the multiple integrated wafer-level cameras 20A and replaced with dicing tapes 42 (step S4).

[0085] The first resin 28 and the second resin 29 are cut (diced) so that a predetermined thickness remains on the side of each wafer-level camera 20A (step S5). As a result, the multiple diced camera units 20 are bonded to the dicing tape 42, as shown in column C of Figure 7.

[0086] Subsequently, each camera unit 20 is peeled off and picked up from the dicing tape 42 (step S6), and the process shown in Figure 6 is completed.

[0087] As described above, the picked-up camera unit 20 is connected to the three-dimensional wiring board 11 by reflow.

[0088] According to the first embodiment, the tensile modulus of the second resin 29 covering the side surface 25s of the first adhesive 25 is made smaller than that of the first resin 28. Therefore, the stress that the second resin 29 applies to the first adhesive 25 due to changes in at least one of temperature and humidity can be made smaller than when the side surface 25s is covered with the first resin 28. This prevents cracks from occurring in the first adhesive 25 due to stress caused by changes in at least one of temperature and humidity in the resin covering the side surface of the wafer level camera 20A.

[0089] Specifically, during manufacturing when the camera unit 20 is connected to the three-dimensional wiring board 11 by high-temperature reflow, and when the endoscope 1 is used in high-temperature, low-temperature, or high-humidity environments, the stress applied to the first adhesive 25 can be reduced, and cracks in the first adhesive 25 can be prevented.

[0090] Furthermore, the difference between the linear expansion coefficient of the second resin 29 and the linear expansion coefficient of the first adhesive 25 was made smaller than the difference between the linear expansion coefficient of the first resin 28 and the linear expansion coefficient of the first adhesive 25. As a result, the difference in the rate of change of length between the second resin 29 and the first adhesive 25 due to temperature changes becomes smaller than the difference in the rate of change of length 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.

[0091] Furthermore, the second resin 29 further covers at least a portion of the side surface 26s of the second adhesive 26. This reduces the stress applied to the second adhesive 26 during manufacturing and use, and prevents cracks from forming in the second adhesive 26.

[0092] Since the side of the optical element 21 facing the incident light is covered with the first light-shielding resin 28, unwanted light can be prevented from entering the optical element 21.

[0093] According to the manufacturing method for the camera unit 20 described with reference to Figures 6 and 7, multiple camera units 20 can be manufactured in a single batch. Therefore, there is no need to encapsulate each individual camera unit 20 with resin. As a result, multiple camera units 20 can be manufactured in an automated and mechanized process, thereby reducing manufacturing costs.

[0094] As described above, in the camera unit of the first embodiment, the boundary BL between the first resin 28 and the second resin 29 is located on the side surface 21s of the optical element 21. In other words, the interface between the first resin 28 and the second resin 29 is located between the incident surface and the exit surface of the optical element 21.

[0095] In other words, the camera unit is Optical elements and An image sensor comprising a cover glass, a solid-state image sensor, and a first adhesive for bonding the cover glass and the solid-state image sensor, A second adhesive for bonding the optical element and the cover glass, A first light-shielding resin covering a portion of the side surface of the optical element, The device comprises a second resin that covers the side of the optical element not covered by the first resin, the side of the first adhesive, and the side of the solid-state image sensor, and does not cover the first resin. The tensile modulus of the second resin is smaller than that of the first resin.

[0096] [Modified version of the first embodiment] The modified camera unit, imaging module, and endoscope (camera unit, etc.) are similar to the camera unit, etc. of the first embodiment and have the same effect. For this reason, in the following description, components with the same function are denoted by the same reference numerals and their descriptions are omitted.

[0097] For example, as shown in Figure 8, in this modified camera unit, the boundary BL between the first resin 28 and the second resin 29 is located on the side of the (D) cover glass 24.

[0098] Furthermore, the boundary BL between the first resin 28 and the second resin 29, as shown in Figure 9, may be located at any of the following locations: (A) the interface between the optical element 21 and the second adhesive 26, (B) the side surface of the second adhesive 26, (C) the interface between the second adhesive 26 and the cover glass 24, (D) the side surface of the cover glass 24, or (E) the interface between the cover glass 24 and the first adhesive 25. In Figure 9, (X) indicates the position of the boundary BL in the camera unit of the first embodiment (side surface 21s of the optical element 21).

[0099] In other words, the camera unit of this modified example is Optical elements and An image sensor comprising a cover glass, a solid-state image sensor, and a first adhesive for bonding the cover glass and the solid-state image sensor, A second adhesive for bonding the optical element and the cover glass, A first light-shielding resin covering at least all sides of the optical element, The present invention comprises a second resin that covers the side surface of the solid-state image sensor from the side surface of the second adhesive, which is not covered by the first resin, and which does not cover the first resin, The interface between the first resin and the second resin is located between the interface between the optical element and the second adhesive and the interface between the cover glass and the first adhesive. The tensile modulus of the second resin is smaller than that of the first resin.

[0100] It should be noted that the present invention is not limited to the embodiments described above. The present invention can be implemented by modifying its components during the implementation stage, without departing from the spirit of the invention. Furthermore, various forms of the invention can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be deleted from all the components disclosed in the embodiments. Moreover, components from different embodiments may be appropriately combined. Thus, it goes without saying that various modifications and applications are possible without departing from the spirit of the invention. [Explanation of Symbols]

[0101] 1… Endoscope 2… Insertion part 2a...Tip 2b... Curved section 2c...Flexible tube section 3...Operation unit 3a...Gripping part 3b... Curved operation knob 3c... Operation button 3D…Instrument insertion port 3e... Instrument raising lever 4…Universal Cable 4a… Connector 6…Lighting unit 7...Elevating platform 10…Imaging module 11...Three-dimensional wiring board 12…Assembly components 13...Convex member 13b...Substrate 13c... Cavity 13w…side wall 20...Camera unit 20A... Wafer-level camera 20b... Bottom of the camera unit 20s... Side of the camera unit 21…Optical elements 21a…Optical aperture 21s... Side view of optical element 22…Image sensor 23… Solid-state image sensor 23a... Solder bump 23s... Side view of the solid-state image sensor 24... Cover glass 24s… Side of the cover glass 25... The first adhesive 25s… First adhesive side 26… Cover glass 26s... Second side of adhesive 28…First resin 29…Second resin 31…The third resin 41…Support board 42…Dicing tape

Claims

1. An image sensor comprising an optical element, a cover glass, a solid-state image sensor, and a first adhesive positioned between the cover glass and the solid-state image sensor for bonding the cover glass and the solid-state image sensor, A second adhesive for bonding the optical element and the cover glass, A first resin covering at least a portion of the side surface of the optical element, The device comprises a second resin covering at least the side surface of the solid-state image sensor, The tensile modulus of the second resin is smaller than that of the first resin. The first resin has light-shielding properties, The second resin is not covered by the first resin, and does not cover the first resin. A camera unit characterized in that the interface between the first resin and the second resin is located between the position between the incident surface and the exit surface of the optical element and the position of the interface between the cover glass and the first adhesive.

2. The camera unit according to claim 1, characterized in that the first adhesive is in contact with the cover glass and the solid-state image sensor.

3. The camera unit according to claim 2, characterized in that the first adhesive is provided in all areas between the cover glass and the imaging surface of the solid-state image sensor.

4. The camera unit according to claim 1, characterized in that the second resin is in contact with the side surface of the first adhesive.

5. The camera unit according to claim 1, characterized in that the second resin covers the side surface of the solid-state image sensor from the side surface of the second adhesive.

6. The camera unit according to Claim 1, characterized in that, at temperatures below 80°C or 80°C or lower, the difference between the linear expansion coefficient of the second resin and the linear expansion coefficient of the first adhesive is smaller than the difference between the linear expansion coefficient of the first resin and the linear expansion coefficient of the first adhesive.

7. An image sensor comprising an optical element, a cover glass, a solid-state image sensor, and a first adhesive positioned between the cover glass and the solid-state image sensor for bonding the cover glass and the solid-state image sensor; a camera unit comprising a second adhesive for bonding the optical element and the cover glass, a first resin covering at least a portion of the side surface of the optical element, and a second resin covering the side surface of the first adhesive, wherein the tensile modulus of the second resin is smaller than that of the first resin, the first resin has light-shielding properties, the second resin is not covered by the first resin and does not cover the first resin, and the interface between the first resin and the second resin is located between the position between the incident surface and the exit surface of the optical element and the position of the interface between the cover glass and the first adhesive; A side wall surrounds the camera unit, having a distance from the side surface of the camera unit, A base to which the camera unit is connected, and a three-dimensional wiring board having a cavity formed therein, An imaging module characterized by comprising a third resin located between the side surface of the camera unit and the side wall.

8. The imaging module according to claim 7, characterized in that the first adhesive is in contact with the cover glass and the solid-state image sensor.

9. The imaging module according to claim 8, characterized in that the first adhesive is provided in all areas between the cover glass and the imaging surface of the solid-state image sensor.

10. The imaging module according to claim 7, characterized in that the second resin is in contact with the side surface of the first adhesive.

11. The imaging module according to claim 7, characterized in that the second resin covers the side surface of the solid-state image sensor from the side surface of the second adhesive.

12. The imaging module according to claim 7, characterized in that, at temperatures below 80°C or 80°C or lower, the difference between the linear expansion coefficient of the second resin and the linear expansion coefficient of the first adhesive is smaller than the difference between the linear expansion coefficient of the first resin and the linear expansion coefficient of the first adhesive.

13. The imaging module according to claim 7, characterized in that the tensile modulus of the third resin is the same as the tensile modulus of the first resin.

14. An image sensor comprising an optical element, a cover glass, a solid-state image sensor, and a first adhesive positioned between the cover glass and the solid-state image sensor for bonding the cover glass and the solid-state image sensor, A second adhesive for bonding the optical element and the cover glass, A first resin covering at least a portion of the side surface of the optical element, The present invention comprises a second resin covering the side surface of the first adhesive, The tensile modulus of the second resin is smaller than that of the first resin. The first resin has light-shielding properties, The second resin is not covered by the first resin, and does not cover the first resin. A camera unit in which the interface between the first resin and the second resin is located between the position between the incident surface and the exit surface of the optical element and the position of the interface between the cover glass and the first adhesive, A three-dimensional wiring board comprising a cavity formed by a side wall that surrounds the camera unit with a distance between it and the side surface of the camera unit, and a base to which the camera unit is connected, An endoscope comprising: an imaging module having a third resin located between the side surface of the camera unit and the side wall; and an insertion portion being inserted into a subject, wherein the imaging module is provided at the tip of the insertion portion.

15. The endoscope according to claim 14, characterized in that the first adhesive is in contact with the cover glass and the solid-state image sensor.

16. The endoscope according to claim 15, characterized in that the first adhesive is provided in all areas between the cover glass and the imaging surface of the solid-state image sensor.

17. The endoscope according to claim 14, characterized in that the second resin is in contact with the side surface of the first adhesive.

18. The endoscope according to claim 14, characterized in that the second resin covers the side surface of the solid-state image sensor from the side surface of the second adhesive.

19. The endoscope according to claim 14, characterized in that, at temperatures below 80°C or 80°C or lower, the difference between the linear expansion coefficient of the second resin and the linear expansion coefficient of the first adhesive is smaller than the difference between the linear expansion coefficient of the first resin and the linear expansion coefficient of the first adhesive.

20. The endoscope according to claim 14, characterized in that the tensile modulus of the third resin is the same as the tensile modulus of the first resin.

Images