Cemented lenses, lens units, camera modules, imaging systems, and mobile bodies

Abstract

To provide a cemented lens which allows for filling a space between lenses with a sufficient amount of an adhesive when bonding lenses together with the adhesive and offers desired optical properties even if the adhesive overflows to a fitting portion, and to provide a camera module equipped with the same, an image capturing system, and a mobile vehicle.SOLUTION: Lenses 17, 18 are bonded together with an adhesive and flange portions 17a, 18a in outer peripheries of the lenses are bonded together at a fitting portion 60. An escape space 70 for allowing an excess of the adhesive to escape and accumulate is provided as a part of the fitting portion 60 so as to allow an inter-lens space to be filled with a sufficient amount of the adhesive and provide desired optical properties even if the adhesive overflows to the fitting portion.SELECTED DRAWING: Figure 4

Description

Technical Field

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[0001] The present invention relates to a bonded lens in which lenses are bonded together with an adhesive, a lens unit including the bonded lens, a camera module including the lens unit, an imaging system, and a moving body.

Background Art

[0002] In order to perform corrections such as chromatic aberration with a smaller number of lenses, a bonded lens in which lens surfaces of different lenses are bonded together with an adhesive may be used (see, for example, Patent Document 1). In a bonded lens, an adhesive of a sufficient amount (thickness) is required so that gaps and peeling between the lenses do not occur. In such a bonded lens, the lenses are bonded together with their optical axes aligned by fitting flange portions provided on the outer peripheral portions of the lenses.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in a bonded lens, if an adhesive of a sufficient amount is used so that gaps and peeling between the lenses do not occur, there is a risk that the adhesive may overflow beyond the bonding surfaces of the lenses to the fitting portions between the flange portions on the outer peripheral portions. When adhesive overflows into the mating area in this way, it often results in adhesive being interposed between the mating surfaces, preventing the desired optical properties from being obtained. For example, if the adhesive is unevenly interposed between the mating surfaces, the lenses will be bonded at an angle, causing lens tilt. Even if the adhesive is uniformly interposed between the mating surfaces, the thickness of the bonded lenses will change, worsening the precision of lens installation, and as a result, the desired optical properties cannot be obtained. Furthermore, if a sufficient amount of adhesive is not filled between the lenses, a gap will form between them, causing light reflection and refraction at the adhesive interface, resulting in ghosting and preventing the desired optical properties from being obtained.

[0005] The present invention has been made in view of the above circumstances, and aims to provide a cemented lens that can fill a sufficient amount of adhesive between lenses when bonding them together with adhesive, and that can obtain desired optical properties even if the adhesive overflows into the mating portion, as well as a camera module, imaging system, and mobile body equipped with this cemented lens. [Means for solving the problem]

[0006] To solve the aforementioned problems, the present invention provides a bonded lens in which lenses are bonded together with an adhesive, and the flange portions of the outer periphery of these lenses are fitted together with a fitting portion, A feature is that a portion of the fitting portion is provided with a relief space for releasing and accumulating excess adhesive.

[0007] In this invention, a relief space is provided in a part of the fitting portion that connects the flange portions of the lenses, allowing excess adhesive to escape and accumulate. Therefore, even if excess adhesive overflows into the fitting portion when a sufficient amount of adhesive is filled between the lenses, the excess adhesive flows into the relief space and accumulates. This ensures that a sufficient amount of adhesive is filled between the lenses without any gaps, preventing the occurrence of ghosting, and since the excess adhesive does not interpose between the fitting surfaces of the fitting portion, lens tilt does not occur. Consequently, the desired optical characteristics can be obtained.

[0008] In the above configuration of the present invention, the relief spaces may be provided in a plurality at predetermined intervals in the circumferential direction of the lens.

[0009] With this configuration, excess adhesive is dispersed and accumulated in multiple relief spaces provided at predetermined intervals around the lens, allowing the excess adhesive to be smoothly stored in the relief spaces.

[0010] Furthermore, in the above configuration of the present invention, the plurality of relief spaces may be arranged point-symmetrically with respect to the center of the lens.

[0011] With this configuration, the relief space is arranged point-symmetrically with respect to the center of the lens, allowing excess adhesive to accumulate uniformly in the relief space.

[0012] Furthermore, in the above configuration of the present invention, the multiple escape spaces may all have the same volume.

[0013] With this configuration, since all of the relief spaces have the same volume, the fitting portions that provide these relief spaces can be uniformly arranged in the circumferential direction of the lens. Therefore, the flange portions of the lenses can be fitted together in a balanced manner.

[0014] The present invention also provides a lens unit having the cemented lens, a camera module having the lens unit, an imaging system having the camera module, and a mobile body equipped with the imaging system. The same effects as those of the cemented lens described above can be obtained with such a lens unit, camera module, imaging system, and mobile body. The term "mobile body" refers to any object that can be moved, such as a vehicle. [Effects of the Invention]

[0015] According to the present invention, when bonding lenses together with an adhesive, a sufficient amount of the adhesive can be filled between the lenses, and even if the excess adhesive overflows into the fitting portion, the excess adhesive flows into the escape space and is stored, so that desired optical characteristics can be obtained.

Brief Description of the Drawings

[0016] [Figure 1] It is a schematic cross-sectional view showing a lens unit according to an embodiment of the present invention. [Figure 2] It shows a bonded lens according to the first embodiment of the present invention, and is a bottom view of the lens on the object side. [Figure 3] The same, (a) is a schematic cross-sectional view taken along line A-A in FIG. 2, and (b) is an enlarged view of a circular portion X in (a). [Figure 4] The same, (a) is a schematic cross-sectional view taken along line B-B in FIG. 2, and (b) is an enlarged view of a circular portion X in (a). [Figure 5] It is a schematic cross-sectional view of a main part showing a bonded lens according to the second embodiment of the present invention. [Figure 6] It is a schematic cross-sectional view of a main part showing a bonded lens according to the third embodiment of the present invention. [Figure 7] It is a schematic cross-sectional view of a camera module according to an embodiment of the present invention. [Figure 8] It is a schematic view of a vehicle as a moving body on which an imaging system (in-vehicle system) including a camera module according to an embodiment of the present invention is mounted. [Figure 9] It is a block diagram showing the configuration of an imaging device constituting the imaging system shown in FIG. 8.

Modes for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment contributes to "9. Build the foundation of industry and technological innovation" of the Sustainable Development Goals (SDGs) proposed by the United Nations. Note that the lens unit of the present embodiment described below is particularly for a camera module such as an in-vehicle camera. For example, it is fixedly installed on the outer surface side of an automobile, and the wiring is drawn into the automobile and connected to a display or other devices. In addition, in FIGS. 1, 3 to 7, the hatching of a plurality of lenses and spacers is omitted.

[0018] FIG. 1 shows a lens unit 11 having a bonded lens 30 according to the first embodiment. This lens unit 11 is, for example, for an in-vehicle camera, and at least the object-side end (the upper end in FIG. 1) of the lens unit 11 is exposed and installed on the outside of the automobile.

[0019] The lens unit 11 includes a cylindrical lens barrel 12, a plurality (for example, seven) of lenses 13, 14, 15, 16, 17, 18, 19 arranged in the lens barrel 12, two aperture members 21, 22, and two annular spacers 24A, 24B. The in-vehicle camera including this lens unit 11 includes the lens unit 11, a substrate having an image sensor not shown, and an installation member not shown for installing the substrate on a vehicle such as an automobile. Further, the lens 13 is a glass lens, and the lenses 14 to 19 are resin lenses, but it is not limited thereto (for example, the lens 13 may be a resin lens). In addition, an antireflection film, a hydrophilic film, a water-repellent film, etc. may be provided on the surfaces of the lenses 13 to 19 as necessary.

[0020] The plurality of lenses 13 to 19 fixed and supported by the lens barrel 12 are arranged in a state where their respective optical axes are aligned, and are arranged in a state where the lenses 13 to 19 are arranged along one optical axis О, constituting a group of lens groups L used for imaging. In addition, the lens 17 and the lens 18 are a bonded lens 30 bonded by an adhesive, and the bonded lens 30 includes the lens 17 and the lens 18.

[0021] Of the two aperture members 21 and 22, the first aperture member 21 from the object side (one end of the lens barrel 12) is positioned between the second lens 14 and the spacer 24A from the object side. The second aperture member 22 from the object side is positioned between the sixth lens 18 and the seventh lens 19 from the object side. The aperture members 21 and 22 are either "aperture diaphragms" that limit the amount of transmitted light and determine the F-number, which is an indicator of brightness, or "light-shielding diaphragms" that block light rays that cause ghosting or aberrations.

[0022] Furthermore, in this embodiment, an O-ring 26 is interposed between the lens 13 located closest to the object and the lens barrel 12 as a sealing member to prevent water and dust from entering the lens group L inside the lens barrel 12. In this case, a stepped diameter reduction portion 13b is provided on the outer circumferential surface 13a of the lens 13, where the diameter is smaller on the image side of the lens 13. The O-ring 26 is fitted onto this diameter reduction portion 13b, and the O-ring 26 is compressed radially between the outer circumferential surface 13a of the lens 13 and the inner circumferential surface of the lens barrel 12, thereby sealing the object-side end of the lens barrel 12. Furthermore, the sealing member interposed between the lens 13 and the lens barrel 12 is not limited to an O-ring 26, but can be any form of annular body that can seal the space between the lens 13 and the lens barrel 12.

[0023] Furthermore, with the lens group L assembled and housed within its internal housing space, the crimping portion 23 at the object-side end (upper end in Figure 1) of the lens barrel 12 is thermally crimped radially inward, thereby fixing the lens 13, which is closest to the object in the lens group L, to the object-side end of the lens barrel 12 in the optical axis direction by this crimping portion 23. In this case, to ensure stable crimping, the portion of the glass lens 13 to which the crimping portion 23 is pressed is formed as a flat portion 13c that is cut diagonally in a planar shape. Note that the means for fixing the first lens 13 to the object-side end of the lens barrel 12 in the optical axis direction is not limited to such a crimping portion 23. For example, if the lens barrel 12 is made of metal, the first lens 13 may be fixed to the object-side end of the lens barrel 12 in the optical axis direction by a cap that is screwed onto the object-side end of the lens barrel 12.

[0024] Furthermore, the image-side end (lower end in Figure 1) of the lens barrel 12 is provided with an inner flange portion 25 having an opening smaller in diameter than the lens 19 located furthest to the image side of the lens group L. The multiple lenses 13-19, aperture members 21, 22, and spacers 24A, 24B that constitute the lens group L are held and fixed in the optical axis direction within the lens barrel 12 by this inner flange portion 25 and the crimping portion 23.

[0025] In this embodiment, as shown in Figure 3, the bonded lens 30 is formed by bonding a concave lens 17 on the object side and a convex lens 18 on the image side with an adhesive, and these lenses 17 and 18 are made of resin lenses. In the following, the concave lens 17 may be simply referred to as lens 17, and the convex lens 18 may be simply referred to as lens 18. When bonding the concave lens 17 and the convex lens 18, the bonding process should be performed with the concave lens 17 facing downwards and the convex lens 18 facing upwards. In other words, the bonding process should be performed with the orientation reversed from that shown in Figure 3.

[0026] The concave lens 17 has a concave surface 31 on the image side and a convex surface 36 on the object side. The concave lens 17 also comprises a lens portion 17b having the desired lens function and an annular flange portion 17a formed on the outer edge of its outer periphery. When bonding the concave lens 17 and the convex lens 18, the concave surface 31 of the concave lens 17 is placed facing upwards, and adhesive is injected into this concave surface 31.

[0027] The convex lens 18 has a convex surface 41 on the object side through which light passes and a convex surface 46 on the image side. The convex lens 18 also has a lens portion 18b having a desired lens function and an annular flange portion 18a formed on its outer circumference. Furthermore, the concave surface 31 on the image side of the concave lens 17 and the convex surface 41 on the object side of the convex lens 18 have an effective diameter r as the range in which they function as lenses. When bonding these concave lens 17 and convex lens 18 together, the convex surface 41 of the object-side convex lens 18 is joined to the concave surface 31 of the image-side concave lens 17 using an adhesive. In this case, the adhesive layer 51 is formed between the concave surface 31 of the concave lens 17 and the convex surface 41 of the convex lens 18. Although the adhesive is not shown in Figure 3, the adhesive layer 51 is filled with adhesive. Furthermore, the adhesive forming the adhesive layer 51 extends radially outward to the fitting portion 60, which will be described later.

[0028] The flange portion 17a of lens 17 and the flange portion 18a of lens 18 are fitted together. Specifically, as shown in Figure 3(b), the flange portion 17a has a recess 52 and a protrusion 53 adjacent to each other in the radial direction on the image-side surface. The recess 52 is formed in a groove shape along the circumferential direction of the flange portion 17a, and the protrusion 53 is formed in a projection shape along the circumferential direction of the flange portion 17a. In addition, between the recess 52 and the protrusion 53, an inclined surface 54 is formed along the circumferential direction of the flange portion 17a, inclined with respect to the radial direction of the flange portion 17a. This inclined surface 54 is inclined radially outward as it approaches the image side (downward side in Figure 3).

[0029] Furthermore, the flange portion 18a has a convex portion 55 and a concave portion 56 provided radially adjacent to each other on the object-side surface. The convex portion 55 is formed as a projection along the circumferential direction of the flange portion 18a, and the concave portion 56 is formed as a groove along the circumferential direction of the flange portion 18a. In addition, an inclined surface 57 is formed between the convex portion 55 and the concave portion 56, inclined with respect to the radial direction of the flange portion 18a. This inclined surface 57 is inclined radially outward as it approaches the image side (downward side in Figure 3). Furthermore, this inclined surface 57 and the aforementioned inclined surface 54 are inclined at approximately the same angle.

[0030] Then, the flange portion 17a and the flange portion 18a are fitted together by interlocking the recess 52 of the flange portion 17a with the protrusion 55 of the flange portion 18a, interlocking the recess 56 of the flange portion 18a with the protrusion 53 of the flange portion 17a, and further by bringing the inclined surface 54 of the flange portion 17a and the inclined surface 57 of the flange portion 18a into contact with each other. The fitting portion 60 is formed by a recessed portion 52 and a protruding portion 55 that interlock with each other, a recessed portion 56 and a protruding portion 53 that interlock with each other, and inclined surfaces 54 and 57 that abut each other, and the flange portion 17a of lens 17 and the flange portion 18a of lens 18 are fitted together by this fitting portion 60.

[0031] Furthermore, a relief space 70 is provided in a part of the fitting portion 60 to release and accumulate excess adhesive used to bond the lenses 17 and 18. In other words, as shown in Figures 2 and 4(a) and 4(b), a recess 71 is formed on the inner circumferential surface of the protrusion 53 provided on the flange portion 17a, and by forming this recess 71, a part of the recess 52 provided on the flange portion 17a extends radially outward. The space enclosed by the recess 71, the widened portion of the recess 52 provided in the flange portion 17a, and the inclined surface 57 provided in the flange portion 18a constitutes the relief space 70. The radially outer opening of the void 51k, which extends between the recess 52 and the protrusion 55 to form the adhesive layer 51, is connected to this relief space 70. Therefore, any excess adhesive used to bond the lenses 17 and 18 flows from the void 51k into the relief space 70.

[0032] As shown in Figure 2, multiple such relief spaces 70 are provided in the circumferential direction of the lenses 17 and 18 at predetermined intervals and with a predetermined length (six in this embodiment), and are arranged point-symmetrically with respect to the centers of the lenses 17 and 18. Of the six relief spaces 70, one relief space 70A(70) has a longer circumferential length compared to the other five relief spaces 70, but a shallower radial depth, and has the same volume as each of the other five relief spaces 70. Therefore, the one relief space 70A and the five relief spaces 70 are arranged point-symmetrically with respect to the centers of the lenses 17 and 18, and all have the same volume. The one relief space 70A is positioned at a location corresponding to the gate when the lens 17 is injection molded from resin.

[0033] In the cemented lens 30 of this embodiment, a relief space 70 is provided in a part of the fitting portion 60 that fits the flange portions 17a and 18a of the lenses 17 and 18 together, allowing excess adhesive to escape and accumulate. Therefore, even if excess adhesive overflows to the fitting portion 60 when a sufficient amount of adhesive is filled between the lenses 17 and 18, the excess adhesive flows into and accumulates in the relief space 70. This ensures that a sufficient amount of adhesive is filled between the lenses 17 and 18 without any gaps, preventing the occurrence of ghosting. Furthermore, since excess adhesive does not interpose between the fitting surfaces of the fitting portion 60 (between the tip surface of the convex portion 53 and the bottom surface of the concave portion 56, and between the inclined surfaces 54 and 55), lens tilt does not occur. Consequently, the desired optical characteristics can be obtained.

[0034] Furthermore, since multiple relief spaces 70 and 70A are provided at predetermined intervals in the circumferential direction of the lenses 17 and 18, excess adhesive is dispersed and accumulated in these relief spaces 70 and 70A. Therefore, excess adhesive can be smoothly accumulated in the relief spaces 70 and 70A. Furthermore, since the relief spaces 70 and 70A are arranged point-symmetrically with respect to the centers of lenses 17 and 18, excess adhesive can be accumulated in a uniform amount in the relief spaces 70 and 70A. Furthermore, since the multiple relief spaces 70 and 70A are point-symmetrical and all have the same volume, the fitting portions 60 that have these relief spaces 70 and 70A in part can be uniformly arranged in the circumferential direction of the lenses 17 and 18. Therefore, the flange portions 17a and 18a of the lenses 17 and 18 can be fitted together in a balanced manner.

[0035] In this embodiment, a relief space 70 is provided by forming a recess 71 on the inner circumferential surface of a protrusion 53 on the flange portion 17a. However, instead of this, or in addition, a relief space may be provided by forming a recess on the outer circumferential surface of a protrusion 55 on the flange portion 18a.

[0036] Figure 5 is an enlarged cross-sectional view of the main part of the cemented lens according to the second embodiment, and Figure 6 is an enlarged cross-sectional view of the main part of the cemented lens according to the third embodiment.

[0037] In the bonded lens 30A of the second embodiment, when an adhesive reservoir 80 is provided in an annular shape radially outward from the adhesive layer between the bonded lenses 17A and 18A and radially inward from the fitting portion 60A between the flange portions, a relief space 70A is further provided radially outward from this adhesive reservoir 80. The other configurations are the same as those of the bonded lens 30 of the embodiment. In other words, multiple relief spaces 70A are provided at predetermined intervals in the circumferential direction of the lenses 17A and 18A, are arranged point-symmetrically with respect to the centers of the lenses 17A and 18A, and furthermore, all of the multiple relief spaces 70A have the same volume. In this modified example, the relief space 70A is provided by forming a recess 71A on the inner surface of the protrusion 55A provided on the flange portion of the lens 18A.

[0038] In the second embodiment, in addition to obtaining the same effects as the bonded lens 30 of the first embodiment, if excess adhesive exceeds the adhesive layer between the lenses 17A and 18A, the excess adhesive flows into the adhesive reservoir 80. However, since a relief space 70A is provided radially outside the adhesive reservoir 80, even if the excess adhesive overflows from the adhesive reservoir 80, the excess adhesive can be allowed to flow into the relief space 70A and be stored there.

[0039] In the third embodiment of the bonded lens 30B, when an adhesive reservoir 81 is provided in an annular shape radially outward from the adhesive layer between the bonded lenses 17B and 18B and radially inward from the fitting portion 60B between the flange portions, a relief space 70B is further provided radially outward from this adhesive reservoir 81. The other configurations are the same as those of the bonded lens 30 of the embodiment. In other words, multiple relief spaces 70B are provided at predetermined intervals in the circumferential direction of the lenses 17B and 18B, are arranged point-symmetrically with respect to the centers of the lenses 17B and 18B, and furthermore, all of the multiple relief spaces 70B have the same volume. In this modified example, the relief space 70B is provided by forming a recess 71B on the inner surface of the protrusion 53A provided on the flange portion of the lens 17B.

[0040] In the third embodiment, the same effects as the bonded lens 30 of the first embodiment can be obtained. Furthermore, similar to the first modification, if excess adhesive overflows the adhesive layer between the lenses 17B and 18B, the excess adhesive flows into the adhesive reservoir 81. However, since a relief space 70B is provided radially outside the adhesive reservoir 81, even if the excess adhesive overflows further from the adhesive reservoir 81, the excess adhesive can be allowed to flow into the relief space 70B and be stored there.

[0041] Figure 7 is a schematic cross-sectional view of the camera module 300 of this embodiment, which has a lens unit 11 configured as described above. As shown in the figure, the camera module 300 comprises an upper case (camera case) 301, which is an exterior component, and a mount (base) 302 that holds the lens unit 11. The camera module 300 also includes a sealing member 303 and a package sensor (image sensor) 304.

[0042] The upper case 301 engages with a flange portion 27 provided in a flange shape on the outer circumferential surface of the lens barrel 12, and is a component that exposes the object-side end of the lens unit 11 and covers the other parts. The upper case 301 may engage with a flange portion 28 provided in a flange shape on the outer circumferential surface of the lens barrel 12 on the object side of the flange portion 27. The mount 302 is located inside the upper case 301 and has a female thread 302a that engages with the male thread 11a of the lens unit 11. The sealing member 303 is a member interposed between the inner surface of the upper case 301 and the outer surface of the lens barrel 12 of the lens unit 11, and is a member for maintaining airtightness inside the upper case 301.

[0043] The package sensor 304 is positioned inside the mount 302, facing the lens 19, and is located in a position to receive the image of the object formed by the lens unit 11. The package sensor 304 is equipped with a CCD or CMOS sensor, and converts the light that is focused and reaches it through the lens unit 11 into an electrical signal. The converted electrical signal is then converted into analog or digital data, which are components of the image data captured by the camera.

[0044] Figure 8 schematically shows a vehicle 240 as a mobile body on which an in-vehicle system (imaging system) comprising an imaging device 250 including the camera module 300 shown in Figure 7 is mounted. As shown in the figure, the imaging device 250 can be mounted on the vehicle 240, and Figure 8 is an example of an arrangement illustrating the mounting position of the imaging device 250 on the vehicle 240. The imaging device 250 mounted on the vehicle 240 can also be called an in-vehicle camera and can be installed in various locations on the vehicle 240. For example, the first imaging device 250a may be placed on or near the front bumper as a camera to monitor the area in front of the vehicle 240 while it is in motion. The second imaging device 250b, which also monitors the area in front, may be placed near the rearview mirror inside the vehicle 240. The third imaging device 250c may be placed on the dashboard or inside the instrument panel, etc., as a camera to monitor the driver's driving conditions. The fourth imaging device 250d may be installed at the rear of the vehicle 240 for use as a rear monitor. The imaging devices 250a and 250b can be called front cameras. The third imaging device 250c can be called an in-camera. The fourth imaging device 250d can be called a rear camera. The imaging device 250 is not limited to these, and includes imaging devices installed in various positions, such as a left-side camera that images the left rear side and a right-side camera that images the right rear side.

[0045] The image signal of the image captured by the imaging device 250 can be output to an information processing device 242 and / or a display device 243, etc., within the vehicle 240. These information processing devices 242 and 243 together with the imaging device 250 constitute an in-vehicle system. The information processing device 242 within the vehicle 240 includes a device that processes the image signal acquired by the imaging device 250, recognizes the image, and assists the driver in driving. The information processing device 242 also includes, but is not limited to, a navigation device, a collision damage mitigation braking device, a vehicle-to-vehicle distance control device, and a lane departure warning device. The display device 243 displays the image processed and output by the information processing device 242, but can also receive the image signal directly from the imaging device 250. The display device 243 may employ, but is not limited to, a liquid crystal display (LCD), an organic electro-luminescence (OLED) display, or an inorganic EL display. The display device 243 can display image signals output from the imaging device 250, which captures images from positions that are difficult for the driver to see, such as a rear camera, to the driver (it can output information to the occupants).

[0046] Figure 9 shows the configuration of the imaging device that constitutes the in-vehicle system shown in Figure 8. As shown in the figure, the imaging device 250 according to this embodiment includes a control unit 252, a storage unit 254, and the camera module 300 shown in Figure 5 above.

[0047] The control unit 252 controls the camera module 300 and processes the electrical signals output from the image sensor 304 of the camera module 300. This control unit 252 may be configured as a processor, for example. The control unit 252 may also include one or more processors. The processors may include general-purpose processors that load a specific program and execute a specific function, and dedicated processors specialized for specific processing. Dedicated processors may include application-specific integrated circuits (ICs). Application-specific integrated circuits are also called ASICs (Application Specific Integrated Circuits). The processors may also include programmable logic devices. Programmable logic devices are also called PLDs (Programmable Logic Devices). PLDs may include field-programmable gate arrays (FPGAs). The control unit 252 may be either a system-on-a-chip (SoC) or a system-in-a-package (SiP) in which one or more processors cooperate.

[0048] The storage unit 254 stores various information or parameters related to the operation of the imaging device 250. The storage unit 254 may be composed of, for example, a semiconductor memory. The storage unit 254 may function as a work memory for the control unit 252. The storage unit 254 may store captured images. The storage unit 254 may store various parameters, etc., for the control unit 252 to perform detection processing based on the captured images. The storage unit 254 may be included in the control unit 252.

[0049] As mentioned above, the camera module 300 captures the subject image formed via the lens unit 11 with the image sensor 304 and outputs the captured image. The image captured by the camera module 300 is also called the captured image.

[0050] The image sensor 304 may be composed of, for example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device). The image sensor 304 has an imaging surface in which multiple pixels are arranged. Each pixel outputs a signal that is specified by current or voltage according to the amount of incident light. The signal output by each pixel is also called imaging data.

[0051] The image data may be read out by the camera module 300 for all pixels and taken into the control unit 252 as an image. The image data read out for all pixels is also called the maximum image. The image data may be read out by the camera module 300 for some pixels and taken into the image. In other words, the image data may be read out from pixels within a predetermined acquisition range. The image data read out from pixels within a predetermined acquisition range may be taken into the image. The predetermined acquisition range may be set by the control unit 252. The camera module 300 may obtain the predetermined acquisition range from the control unit 252. The image sensor 304 may capture an image within a predetermined acquisition range from the subject image formed via the lens unit 11.

[0052] It should be noted that the present invention is not limited to the embodiments described above, and can be implemented in various ways without departing from its spirit. For example, in the present invention, the shapes of lenses, lens barrels, etc., are not limited to the shapes of the embodiments described above. Furthermore, without departing from the spirit of the present invention, some or all of the embodiments described above may be combined, or some of the components of one of the embodiments described above may be omitted. [Explanation of Symbols]

[0053] 12 Telescope Tubes 17, 18, 17A, 18A, 17B, 18B lenses 17a, 18a Flange section 30, 30A, 30B cemented lenses 60, 60A, 60B mating section 70, 70A, 70B Escape space 300 Camera Modules 240 vehicles (mobile) L lens group O optical axis

Claims

1. A cemented lens in which lenses are bonded together with adhesive, and the flange portions on the outer periphery of these lenses are fitted together at a fitting portion, A recess is provided in a part of the fitting portion to allow excess adhesive to escape and accumulate. The fitting portion is formed when a convex portion of one lens and a concave portion of the other lens are fitted together, and in this fitted state, the radially inward-facing inclined surface forming the convex portion and the radially outward-facing inclined surface forming the concave portion abut each other radially inward, and the tip surface of the convex portion and the bottom surface of the concave portion abut each other radially outward. The relief space is defined radially by a recess formed in a part of the inclined surface of the protrusion and the inclined surface of the recess, and is defined circumferentially by the side walls of the protrusion formed by the recess, in a cemented lens.

2. The cemented lens according to claim 1, characterized in that the aforementioned clearance spaces are provided in a plurality at predetermined intervals in the circumferential direction of the lens.

3. The cemented lens according to claim 2, characterized in that the plurality of relief spaces are arranged point-symmetrically with respect to the center of the lens.

4. The cemented lens according to claim 2 or 3, characterized in that all of the aforementioned relief spaces have the same volume.

5. A lens unit characterized by having a lens group including a cemented lens as described in any one of claims 1 to 4, and a lens barrel that houses and holds the lens group.

6. A camera module comprising a lens unit as described in claim 5, and an image sensor that converts light collected through the lens group of the lens unit into an electrical signal.

7. An imaging device having a camera module according to claim 6 and a control unit that controls the camera module and processes electrical signals output from the image sensor of the camera module, A processing device for processing image signals acquired by the imaging device, A display device that displays an image processed and output by the aforementioned processing device, An imaging system characterized by having the following features.

8. A mobile body equipped with the imaging system described in claim 7, and characterized in that it outputs information to the occupants using the display device.

Images