Optical instrument, on-vehicle camera, and transport apparatus

Abstract

To provide an optical instrument that is reduced in size and prevents the occurrence of breakage of an electric connection part of an image pickup device and a substrate on which the image pickup device is mounted, an on-vehicle camera, and a transport apparatus.SOLUTION: An optical instrument has a lens, a lens holding member that holds the lens, an image pickup device that receives light transmitted through the lens on an imaging surface and converts the light into an electric signal, and a device holder that holds the image pickup device, which are integrally formed. The device holder holds a surface of the image pickup device that is different from a surface on the opposite side of the imaging surface of the image pickup device and is different from the imaging surface. The device holder includes a first member that includes first material and a second member that includes second material different from the first material in order from a position closer to the lens, in an optical path direction along an optical axis of the lens. The coefficient of linear expansion of the first material is larger than the coefficient of linear expansion of the second material.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to an optical instrument, an on-board camera, and a transportation instrument. [Background technology]

[0002] In recent years, automobiles have been equipped with on-board cameras, such as sensing cameras for driving assistance and autonomous driving functions, and cameras for capturing images of the vehicle's surroundings. Images captured by on-board cameras are used to detect road lines and obstacles through desired image processing, and to control the vehicle.

[0003] From the standpoint of cost and device miniaturization, in-vehicle cameras often have a fixed focus configuration and do not have the autofocus function used in general digital still cameras, etc. In addition, since they are used in transportation equipment where the environmental temperature is prone to change, in-vehicle cameras are required to operate stably in a wide range of environmental temperatures and to maintain excellent performance over the entire range of environmental temperatures.

[0004] Changes in environmental temperature lead to changes in the dimensions of the housing of the vehicle-mounted camera and changes in the focal length of the optical system. For example, the length of the housing in the optical axis direction may increase due to thermal expansion of the material accompanying an increase in environmental temperature. As a result, the distance between the optical system attached to the front of the housing and the image sensor attached to the rear of the housing usually increases with an increase in temperature. In addition, when the environmental temperature increases, the focal length of the optical system usually becomes shorter due to an increase in the lens distance and a change in the temperature characteristics of the refractive index of the lens glass material.

[0005] In order for a fixed-focus vehicle-mounted camera to maintain excellent performance across a wide range of environmental temperatures, it is necessary to hold the image sensor in a position close to the focal position of the optical system, taking into account changes in the focal length of the optical system and dimensional changes in the housing, etc., that occur due to changes in environmental temperature.

[0006] Literature 1 describes how a backplate carrying an image sensor can be provided with a bi-material element designed to curve with changes in temperature, allowing the image sensor to follow thermal displacements of the image focal plane. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Special Publication No. 2019-530887 Summary of the Invention [Problem to be solved by the invention]

[0008] The automotive camera module described in Patent Document 1 has a configuration in which a back plate holds the back surface of an image sensor. Generally, in order to extract an electrical signal from an image sensor, an image sensor is used that is mounted on an element substrate, and an electrical connection is required between the image sensor and the element substrate. Therefore, stress generated by the bending deformation of the back plate due to temperature change acts on the electrical connection between the image sensor and the element substrate, and there is a risk that the electrical connection may break.

[0009] In addition, in the above-mentioned configuration, the rigidity of the image sensor prevents the backplate from bending, so that the bendable backplate itself needs to be made large to allow the amount of deformation required to adequately adjust the position of the image sensor, resulting in a problem of an increase in the size of the device.

[0010] Therefore, an object of the present invention is to provide a compact optical device, an on-board camera, and a transportation device in which breakage of the electrical connection between the imaging element and the element substrate on which the imaging element is mounted is unlikely to occur. [Means for solving the problem]

[0011] The above object can be achieved by the present invention, which is an optical device integrally formed with a lens, a lens holding member for holding the lens, an imaging element for receiving light transmitted through the lens at an imaging surface and converting it into an electrical signal, and an element holder for holding the imaging element, the element holder holds a surface of the imaging element that is different from the surface opposite to the imaging surface of the imaging element and different from the imaging surface, the element holder includes, in order from closest to the lens in the optical path direction along the optical axis of the lens, a first member including a first material and a second member including a second material different from the first material, and the linear expansion coefficient of the first material is greater than the linear expansion coefficient of the second material. Effect of the Invention

[0012] According to the present invention, it is possible to provide a miniaturized optical device, an on-board camera, and a transportation device in which breakage of an electrical connection between an imaging element and a substrate on which the imaging element is mounted is unlikely to occur. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of an in-vehicle camera according to the present invention; [Diagram 2] FIG. 2 is a cross-sectional view of the lens barrel unit of the present invention. [Diagram 3] 1 is a diagram illustrating a configuration of an image sensor unit according to the present invention. [Figure 4] 1A to 1C are diagrams illustrating a configuration of an element holder according to the present invention. [Diagram 5] 5A to 5C are diagrams illustrating a method of fixing an imaging element unit to an element holder according to the present invention. [Figure 6] 6A to 6C are diagrams showing a method of fixing the lens barrel unit to the housing of the present invention. [Figure 7] 10A to 10C are diagrams illustrating a method for positioning and fixing an imaging unit to a housing according to the present invention. [Figure 8] 11A to 11C are diagrams illustrating deformation of the element holder and the position of the image sensor unit in accordance with a change in the environmental temperature according to the present invention. [Figure 9] FIG. 1 is a diagram illustrating a configuration of a transportation device according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is merely an example, and the present invention is not limited to the configurations shown in the drawings.

[0015] In this specification, the temperature of the environment in which an object exists is referred to as the “environmental temperature.” The environmental temperature includes, for example, air temperature, room temperature, temperature inside a vehicle, water temperature, and the like.

[0016] The inventors have studied a configuration for reducing the distance between the focal position of the optical system and the image sensor position when a fixed focal length vehicle-mounted camera is placed under high temperatures. As a result, they have found that by configuring the element holder that holds the image sensor to include multiple materials with different thermal properties, it is possible to reduce the distance between the focal position of the optical system and the image sensor when the environmental temperature changes. As a result of further study, they have found that a configuration can be obtained in which stress caused by deformation of the element holder is less likely to act on the electrical connection portion that extracts electrical signals from the image sensor by having the element holder hold the side of the image sensor (the surface opposite to the imaging surface and the surface different from the imaging surface).

[0017] 1 shows a schematic diagram of a camera module 400, which is an example of an optical device of the present invention. Camera module 400 is connected to an information processing unit 500 to form an in-vehicle camera 1000. Camera module 400 is composed of a lens barrel unit 100, a housing 200, and an imaging unit 300. Lens barrel unit 100 is held in housing 200, and as described below, imaging unit 300 is adhesively fixed to housing 200 with optical adjustments made.

[0018] FIG. 2 is a cross-sectional view showing a cross-section including the optical axis at the center of the lens barrel unit 100. The lens barrel unit 100 includes a lens barrel 10. The lens barrel unit 100 further includes a lens 11, a lens 12, and a retaining ring 14 which are held within the lens barrel 10 and are spaced apart from each other using a ring-shaped spacer 13 which is one of the lens retaining members. The lens barrel 10 is made of a metal material or a resin material, and the lenses 11 and 12 are made of a light-transmitting material such as a glass material or a resin material in order to transmit light.

[0019] A male screw portion (not shown) provided on the outer diameter portion of the retaining ring 14 which is one of the lens retaining members is screwed into a female screw portion (not shown) provided on the inner diameter portion of the lens barrel 10, whereby the lens 11, the lens 12, and the spacer 13 are fixed. Further, the lens barrel 10 includes a male screw portion 10a for fixing the lens barrel unit 100 to the housing 200 on the outer diameter portion.

[0020] The plane A shown in FIG. 2 is the focal position at the environmental temperature T1 of the lens barrel unit 100, and the plane A' is the focal position at the environmental temperature T2. Here, T1 is a temperature lower than T2 (T1 < T2). When the environmental temperature changes, the focal position fluctuates due to changes in the thickness dimension of the spacer 13, and shape changes and refractive index changes (due to temperature characteristics) of the lenses 11 and 12. Generally, when the environmental temperature rises, the focal length changes to be shorter as shown in FIG. 2.

[0021] Next, the imaging element unit 3 will be described with reference to FIG. 3. FIG. 3(a) is a side view of the imaging element unit 3, and FIG. 3(b) is a rear view of the imaging element 31.

[0022] The imaging element unit 3 includes an imaging element 31 having a photoelectric conversion section therein, and the imaging element 31 is mounted on an element substrate 32 as shown in FIG. 3(a). A subject image formed on an imaging surface by light received by the imaging element 31 after passing through the lens of the lens barrel unit 100 is photoelectrically converted into an electrical signal by the photoelectric conversion section. In this embodiment, a CMOS sensor is used as the imaging element 31, but this is not limited thereto, and other imaging devices such as a CCD type or a CID type may be used. The front side (the side where light is incident) of the imaging element 31 is covered by a cover glass 35. An electrode pad 31g, which is a part of an electrical connection section, is provided on the back side (the side opposite to the side where light is incident) of the imaging element 31, and the electrode pad 31g is electrically connected to the photoelectric conversion section of the imaging element 31.

[0023] The element substrate 32 is electrically connected to the photoelectric conversion unit of the imaging element 31 via the electrode pads 31g, and receives an electrical signal from the imaging element 31. On the rear side of the element substrate 32, a substrate connector 32a that is a part of an electrical connection unit that is electrically connected to a control circuit (not shown) of the information processing unit 500 is provided.

[0024] Electrode pads 31g of the imaging element 31 are soldered to lands (not shown) of the element substrate 32 by automatic mounting, thereby electrically connecting the imaging element 31 to the element substrate 32, and thus the imaging element 31 is integrated with the element substrate 32. The element substrate 32 may be a flexible substrate such as a flexible printed circuit (FPC). The cover glass 35 is adhered and fixed to the imaging element 31 in a state of being overlapped on the surface of the imaging element 31, and prevents foreign matter from adhering to the imaging surface of the imaging element 31.

[0025] The electrical signal output from the photoelectric conversion unit of the imaging element 31 is transmitted to the element substrate 32 via the electrode pad 31g, and then transmitted from the element substrate 32 to a control circuit (not shown) of the information processing unit 500 via the substrate connector 32a, where the desired image processing is performed.

[0026] Next, the element holder 33 to which the imaging element unit 3 is positioned and fixed will be described with reference to Fig. 4. Fig. 4(a) is an exploded perspective view of the element holder 33, Fig. 4(b) is a perspective view of a first element holder part 33A, and Fig. 4(c) is a perspective view of a second element holder part 33B.

[0027] 4(a), the element holder 33 is composed of a first element holder part 33A which is a first member and contains a first material, and a second element holder part 33B which is a second member and contains a second material different from the first material. These members are arranged in the order of first element holder part 33A and second element holder part 33B when viewed from the front side of the camera module 400, that is, in the order of closer to the lens in the optical path direction along the optical axis of the lens.

[0028] As the first material, at least one selected from the group consisting of stainless steel, aluminum alloy, copper alloy, polycarbonate resin (PC resin), and polyphenylene sulfide resin (PPS resin) can be used. Note that, from the viewpoint of improving strength, the polycarbonate resin and polyphenylene sulfide resin may contain glass fiber. From the viewpoint of sufficient deformation, the first material is preferably the main component of the first member. Here, the main component refers to a material that accounts for 50 wt% or more of the member.

[0029] The second material may be at least one selected from the group consisting of carbon steel, stainless steel, copper alloy, and aluminum alloy. From the viewpoint of sufficient deformation, the second material is preferably the main component of the second member. Here, the main component refers to a material that accounts for 50 wt% or more of the member.

[0030] As described later, the image sensor unit 3 moves in the optical axis direction due to deformation of the element holder 33 caused by changes in the environmental temperature, so that the image sensor unit 3 is held within a range that ensures the performance of the vehicle-mounted camera 1000 over a wide range of environmental temperatures. Normally, when the environmental temperature rises, the focal length of the optical system becomes shorter, so the image sensor unit 3 needs to be moved in a direction approaching the lens barrel 100.

[0031] In order to realize the movement of the image sensor unit 3 in the above-mentioned direction and the miniaturization of the device, the linear expansion coefficient α of the first material is a is the linear expansion coefficient α of the second material b Furthermore, in order to increase the amount of movement of the image sensor unit 3, it is preferable that the linear expansion coefficient α a and the linear expansion coefficient α of the second material b The difference is 3.5 x 10 ―6 It is preferable that the temperature is 100° C. or higher.

[0032] Here, the linear expansion coefficient α is defined as the elongation rate per unit temperature change. If a solid sample with a length of L0 at a temperature of T0°C elongates by ΔL when heated to T1°C, the linear expansion coefficient α ( / °C) is (ΔL / L0){1 / (T1-T0)}.

[0033] In order to reduce the variation in the amount of deformation caused by the variation in the shape and physical properties of each part, the linear expansion coefficient α of the first material is a is 14.0 x 10 ―6 / ℃ or more 24.0×10 ―6 / °C or less. From the same viewpoint, the linear expansion coefficient α of the second material is preferably b is 9.9 x 10 ―6 / ℃ or more 20.5×10 ―6 / °C or less.

[0034] The first element holder part 33A has an opening 33A1 for exposing the imaging surface of the imaging element 31, and protrusions 33A2 and 33A3 for positioning the first element holder part 33B. The surface of the first element holder part 33A is preferably subjected to an anti-reflection treatment by plating, coating, or the like. That is, the surface of the first element holder part 33A is preferably covered with a material different from the first material that is the main component forming the first element holder part 33A. Here, the main component refers to a material that accounts for 50 wt% or more of the member.

[0035] The second element holder part 33B has an opening 33B1 for exposing the imaging surface of the imaging element 31. The opening 33B1 has protrusions 33B2 and 33B3 protruding toward the rear side of the second element holder part 33B, and protrusions 33B4 and 33B5 protruding toward the rear side are formed on a part of the outer edge of the second element holder part 33B. In addition, a pair of positioning holes 33B6 and a vibration prevention hole 33B7 are formed in the second element holder part 33B. In this embodiment, the protrusions 33B4 and 33B5 both protrude toward the rear side, but this is not limited thereto, and the protrusions 33B4 and 33B5 may both protrude toward the front side, or may protrude in different directions.

[0036] The first element holder part 33A is positioned by fitting the protrusions 33A2 and 33A3 into a pair of positioning holes 33B6 and a vibration prevention hole 33B7 provided in the second element holder part 33B, and is joined to the second element holder part 33B by fastening it at four points with screws 34.

[0037] In this embodiment, the first element holder part 33A and the second element holder part 33B are joined by fastening them with screws at four places, but this is not limited to this. They only need to be joined and integrated at at least two places. The joining means is not limited to fastening with screws. The joining means may be at least one selected from the group consisting of fastening with screws, riveting, welding, fusing, and adhesion. Furthermore, in this embodiment, the connection parts 33B2 and 33B3 with the imaging element unit 3 and the connection parts 33B4 and 33B5 with the housing 200 are provided on the second element holder part 33B, but the above-mentioned multiple connection parts may be provided on the first element holder part 33A.

[0038] Next, a method for fixing the imaging element unit 3 to the element holder 33 will be described with reference to Fig. 5. Fig. 5(a) is a front view showing a state in which the imaging element unit 3 is fixed to the element holder 33, and Fig. 5(b) is a cross-sectional view taken along line A-A in Fig. 5(a).

[0039] The imaging element unit 3 is assembled from the rear side into the element holder 33 so that the imaging element 31 fits into the opening 33B1 of the second element holder part 33B. When assembling the imaging element unit 3 into the element holder 33, the element holder 33 is fixed, and a position adjustment jig is used to adjust the center of the imaging surface in the imaging element 31 to approximately the center of the opening 33B1 provided in the second element holder part 33B.

[0040] After the position adjustment is completed, adhesive 50 is filled into the space between the side surfaces 31a and 31b of the imaging element 31 and the protrusions 33B2 and 33B3 inclined a predetermined amount toward the rear side in the optical axis direction, and then cured. The imaging element unit 3 is fixed to the element holder 33 by the adhesive 50. Since the imaging element unit 3 is inserted from the rear side of the element holder 33 and the side surfaces 31a and 31b of the imaging element 31 are adhesively held, the second element holder part 33B is shaped so as not to overlap with the imaging element 32 in the optical axis direction.

[0041] Since the amount of deformation of element holder 33 varies depending on the thickness of element holder parts 33A and 33B, it is possible to design element holder 33 that enables the desired amount of deformation by changing the thickness of element holder parts 33A and 33B.

[0042] By configuring the protrusions 33B2 and 33B3 to be bonded to the imaging element unit 3, it is possible to ensure a bonding area between the second element holder part 33B and the imaging element unit 3 regardless of the thickness of the second element holder part 33B. In other words, it is possible to ensure the impact resistance of the imaging unit 300. Furthermore, when the adhesive 50 hardens, the protrusions 33B2 and 33B3 of the second element holder part 33B deform, thereby alleviating the stress acting on the imaging element 31 and suppressing deformation of the imaging element 31.

[0043] The protrusions 33B2 and 33B3 are preferably shaped to be inclined a predetermined amount toward the rear side with respect to the optical axis. This causes the space between the side surfaces 31a and 31b of the imaging element 31 and the protrusions 33B2 and 33B3 to become gradually narrower toward the rear side. This shape prevents the adhesive 50 from flowing out to the element substrate 32 side of the imaging element unit 3. The adhesive 50 is preferably highly heat resistant, and specifically, is preferably one having a glass transition temperature (Tg) of 85°C or higher.

[0044] In addition, in the present embodiment, the first element holder part 33A and the second element holder part 33B are integrated together, and then the imaging element unit 3 is fixed to the element holder 33, but this is not limiting. For example, the imaging element unit 3 may be positioned and fixed to the second element holder part 33B, and then the first element holder part 33A may be fixed to the second element holder part 33B.

[0045] Next, a method of attaching barrel unit 100 to housing 200 will be described with reference to Fig. 6. Fig. 6(a) is a cross-sectional view of housing 200, Fig. 6(b) is a rear view of housing 200, and Fig. 6(c) is a cross-sectional view of barrel unit 100 fixed to housing unit 200.

[0046] Housing 200 is provided with female thread portion 200a for mounting barrel unit 100, and has four adhesive grooves 200b on the rear side for filling with adhesive for fixing imaging unit 300. Barrel unit 100 is fixed to housing 200 by screwing male thread portion 10a provided on barrel unit 100 into female thread portion 200a provided on housing 200.

[0047] Next, a method for fixing the imaging unit 300 to the housing 200 will be described with reference to Fig. 7. Fig. 7 shows a state in which the imaging unit 300 is attached and fixed to the housing 200 by adhesive 51 after being incorporated into the housing 200.

[0048] The imaging unit 300 is adjusted so that the imaging surface of the imaging element 31 is located within an allowable error range that can ensure the desired performance of the vehicle-mounted camera 1000, centered on the focal position of the lens barrel unit 100 incorporated in the housing 200. After the adjustment is completed, the imaging unit 300 is fixed to the housing 200 by filling and curing adhesive 51 into the space between the protrusions 33B5 and 33B6 provided on the second element holder part 33B and the adhesive groove 200b provided on the housing 200. The adhesive 51 is preferably highly heat-resistant, and specifically, it is preferable that the adhesive has a glass transition temperature (Tg) of 85° C. or higher.

[0049] Next, the deformation state of the element holder 33 and the movement in the optical axis direction of the image pickup element unit 3 when the environmental temperature changes will be described with reference to Fig. 8. Fig. 8(a) is a cross-sectional view of the camera module 400 at environmental temperature T1, and Fig. 8(b) is a cross-sectional view of the camera module 400 at environmental temperature T2 (T1 <T2)。

[0050] When the environmental temperature rises from T1 to T2, warping occurs in the element holder 33, which is integrally formed of the first element holder part 33A and the second element holder part 33B having different linear expansion coefficients. a and the linear expansion coefficient α of the second material b As mentioned above, the relationship between α a >α bTherefore, element holder 33 deforms so as to become convex on the side of barrel unit 100. In other words, when the environmental temperature rises, element holder 33 deforms so that image sensor 31 approaches the lens.

[0051] Since the image sensor unit 3 is fixed to the element holder 33 via the adhesive 50, the image sensor unit 3 moves in the optical axis direction and approaches the lens barrel unit 100 as the element holder 33 deforms. The amount of deformation of the element holder 33 when the environmental temperature changes is α a and α b The difference can be changed by the size, thickness, fastening position, elastic modulus, etc. of the first element holder part 33A and the second element holder part 33B.

[0052] That is, by considering the change in focal length due to the change in environmental temperature and the change in dimensions of the housing, etc., and appropriately designing the deformation amount of the element holder 33, it is possible to always keep the imaging surface of the imaging element 31 within the above-mentioned allowable error range. Furthermore, it becomes possible for the vehicle-mounted camera 1000 to maintain excellent performance over a wide range of environmental temperatures.

[0053] In addition, since the imaging element 31 is held by the element holder 33 at the side surfaces 31a and 31b, stress due to deformation of the element holder 33 accompanying changes in environmental temperature is less likely to act on the electrical connection between the imaging element 31 and the element substrate 32, and breakage of the electrical connection can be prevented. Furthermore, since the imaging element 31 is held by the element holder 33 at the side surfaces 31a and 31b, the effect of the rigidity of the imaging element 31 on deformation of the element holder 33 can be minimized. Therefore, the element holder 33 can be made smaller, i.e., the camera module 400 can be made smaller.

[0054] The embodiment of the present invention is not limited to the above, and may be a transportation device having a camera module 400 and an information processing unit 500. Fig. 9 shows a schematic configuration diagram of the transportation device of the present invention. The transportation device is, for example, an automobile, a ship, an aircraft, etc. The transportation device of the present invention has an element holder that deforms in response to changes in environmental temperature, and thus can capture images with high accuracy even in a high environmental temperature environment.

[0055] The disclosure of this embodiment includes the following configuration.

[0056] (Configuration 1) Lenses and a lens holding member for holding the lens; an imaging element that receives the light transmitted through the lens on an imaging surface and converts the light into an electrical signal; An element holder for holding the imaging element; An optical device in which the element holder holds a surface of the imaging element that is different from a surface opposite to the imaging surface of the imaging element and different from the imaging surface; the element holder includes, in order from closest to the lens in an optical path direction along an optical axis of the lens, a first member including a first material and a second member including a second material different from the first material; An optical device, wherein the linear expansion coefficient of the first material is greater than the linear expansion coefficient of the second material.

[0057] (Configuration 2) The difference between the linear expansion coefficient of the first material and the linear expansion coefficient of the second material is 3.5×10 ―6 2. The optical device according to claim 1, wherein the temperature is 100° C. or higher.

[0058] (Configuration 3) The linear expansion coefficient of the first material is 14.0×10 ―6 / ℃ or more 24.0×10 ―6 3. The optical device according to claim 1 or 2, wherein the temperature is 0.1 to 1.5° C.

[0059] (Configuration 4) The linear expansion coefficient of the second material is 9.9×10 ―6 / ℃ or more 20.5×10 ―6 4. The optical device according to any one of claims 1 to 3, wherein the temperature is 0.1 to 1.5°C.

[0060] (Configuration 5) 5. The optical device according to any one of configurations 1 to 4, wherein the first material is at least one selected from the group consisting of stainless steel, copper alloy, aluminum alloy, polycarbonate resin, and polyphenylene sulfide resin.

[0061] (Configuration 6) 6. The optical device according to any one of configurations 1 to 5, wherein the second material is at least one selected from the group consisting of carbon steel, stainless steel, a copper alloy, and an aluminum alloy.

[0062] (Configuration 7) 7. The optical device according to any one of configurations 1 to 6, wherein the first member and the second member are joined at least at two locations.

[0063] (Configuration 8) The optical device according to any one of configurations 1 to 7, wherein the first member and the second member are joined by at least one selected from the group consisting of screw fastening, crimping, welding, adhesion, and bonding.

[0064] (Configuration 9) 9. The optical device according to any one of configurations 1 to 8, wherein the element holder holds the imaging element via a resin material having a glass transition temperature of 85° C. or higher.

[0065] (Configuration 10) 10. The optical device according to any one of configurations 1 to 9, further comprising a housing for holding the lens holding member and the element holder.

[0066] (Configuration 11) 11. The optical device according to configuration 10, wherein the housing holds the element holder via a resin material having a glass transition temperature of 85° C. or higher.

[0067] (Configuration 12) 12. The optical device according to any one of configurations 1 to 11, wherein the first member is covered with a material different from the first material.

[0068] (Configuration 13) 13. The optical device according to any one of configurations 1 to 12, wherein at least one of the first member and the second member does not overlap the imaging element in the optical path direction.

[0069] (Configuration 14) The optical device according to any one of configurations 1 to 13, wherein one of the first member and the second member has two protruding portions protruding on the opposite side of the imaging surface of the imaging element.

[0070] (Configuration 15) 15. The optical device according to any one of configurations 1 to 14, wherein the element holder is deformed in response to a change in environmental temperature.

[0071] (Configuration 16) 16. The optical device according to configuration 15, wherein the element holder is deformed so that the imaging element approaches the lens when the environmental temperature rises.

[0072] (Configuration 17) 17. An in-vehicle camera comprising the optical device according to any one of configurations 1 to 16 and an information processing unit that processes the electrical signal.

[0073] (Configuration 18) 17. A transport device comprising the optical device according to any one of configurations 1 to 16, and an information processing unit that processes the electrical signal. [Explanation of symbols]

[0074] 10. Telescope tube 11, 12 Lens 13 Spacer 14 Retaining Ring 33 Element holder 33A First element holder part 33B Second element holder part 50, 51 Adhesive 100 Tube Unit 200 housing units 300 Image sensor unit 400 Camera Module 500 Information Processing Section 1000 In-vehicle Camera 2000 Transportation equipment

Claims

1. Lenses and a lens holding member for holding the lens; an imaging element that receives the light transmitted through the lens on an imaging surface and converts the light into an electrical signal; An element holder for holding the imaging element; An optical device in which the element holder holds a surface of the imaging element that is different from a surface opposite to the imaging surface of the imaging element and different from the imaging surface; the element holder includes, in order from closest to the lens in an optical path direction along an optical axis of the lens, a first member including a first material and a second member including a second material different from the first material; An optical device, wherein the linear expansion coefficient of the first material is greater than the linear expansion coefficient of the second material.

2. The difference between the linear expansion coefficient of the first material and the linear expansion coefficient of the second material is 3.5×10 ―６ 2. The optical device according to claim 1, wherein the temperature is 100° C. or higher.

3. The linear expansion coefficient of the first material is 14.0×10 ―６ / ℃ or more 24.0 x 10 ―６ 2. The optical device according to claim 1, wherein the temperature is 0.15 to 1.5° C. or less.

4. The linear expansion coefficient of the second material is 9.9×10 ―６ / ℃ or more 20.5 x 10 ―６ 2. The optical device according to claim 1, wherein the temperature is 0.15 to 1.5° C. or less.

5. 2. The optical device according to claim 1, wherein the first material is at least one selected from the group consisting of stainless steel, copper alloy, aluminum alloy, polycarbonate resin, and polyphenylene sulfide resin.

6. 2. The optical device according to claim 1, wherein the second material is at least one selected from the group consisting of carbon steel, stainless steel, a copper alloy, and an aluminum alloy.

7. 2. The optical device according to claim 1, wherein the first member and the second member are joined at least at two locations.

8. 2. The optical device according to claim 1, wherein the first member and the second member are joined by at least one selected from the group consisting of screw fastening, caulking, welding, adhesion, and bonding.

9. 2. The optical device according to claim 1, wherein the element holder holds the image pickup element via a resin material having a glass transition temperature of 85[deg.] C. or higher.

10. 2. The optical device according to claim 1, further comprising a housing for holding the lens holding member and the element holder.

11. 11. The optical device according to claim 10, wherein the housing holds the element holder via a resin material having a glass transition temperature of 85[deg.] C. or higher.

12. 2. The optical device according to claim 1, wherein the first member is coated with a material different from the first material.

13. 2 . The optical device according to claim 1 , wherein at least one of the first member and the second member does not overlap the image pickup element in the optical path direction.

14. 2. The optical device according to claim 1, wherein one of the first member and the second member has two protruding portions protruding on a side opposite to the imaging surface of the imaging element.

15. 2. The optical device according to claim 1, wherein the element holder is deformed in response to a change in environmental temperature.

16. 16. The optical device according to claim 15, wherein the element holder is deformed so that the image sensor approaches the lens when the environmental temperature rises.

17. 17. An on-vehicle camera comprising: the optical device according to claim 1; and an information processing unit that processes the electrical signal.

18. A transportation device comprising the optical device according to any one of claims 1 to 16 and an information processing unit that processes the electrical signal.

Images