Lens unit and camera module

Abstract

To provide a lens unit which features a sealing structure capable of coping with corrosion even when a lens group has the same diameter, and to provide a camera module.SOLUTION: A lens unit (101A) is provided, comprising a first sealing member (3) provided on the object side of a first lens (L1) located on the most object side, and a second sealing structure (4) provided on the image side of the first lens (L1).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a lens unit and a camera module.

Background Art

[0002] In recent years, in-vehicle cameras have been mounted on automobiles for purposes such as driving assistance, collision prevention, and driving recording. Such in-vehicle cameras include those arranged inside the vehicle cabin and those arranged outside the vehicle cabin. In the lens barrel of an in-vehicle camera arranged outside the vehicle cabin, in order to prevent water or the like from entering the lens barrel, a method may be used in which a sealing member is attached to the outer periphery of the lens and incorporated into the lens barrel.

[0003] For example, in the lens unit disclosed in Patent Document 1, in a mode in which a plurality of lenses including a first lens arranged on the object side in the optical axis direction and a second lens facing the first lens on the image side in the optical axis direction are held in a lens barrel, a first sealing member that seals between the first lens and the lens barrel, and a second sealing member that seals between the image side surface of the first lens and the lens barrel on the radially inner side of the first sealing member.

[0004] Further, for example, the lens unit disclosed in Patent Document 2 includes a fastening and fixing member that fixes the front end lens located on the most object side of the lens group to the object side end portion of the lens barrel and holds the lens group in the lens barrel in the optical axis direction, and has a co-rotation prevention portion that prevents the co-rotation of the front end lens accompanying the tightening of the fastening and fixing member between the cylindrical lens barrel, the front end lens, and the fastening and fixing member.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the aspect of Patent Document 1 described above, when the lens disposed closest to the object side and the plurality of lenses disposed on the image side have the same diameter, even if a second sealing member is provided inside (closer to the optical axis) than the first sealing member, when corrosion occurs in the vicinity of the first sealing member, it is difficult to ensure the airtightness of the lenses after the second lens.

[0007] Further, in the aspect of Patent Document 2 described above, since the anti-rotation member does not provide a countermeasure against corrosion, the sealing performance in the vicinity of the sealing member may deteriorate in the case of an aluminum lens barrel, etc., and there is a risk that water may enter the lens barrel.

[0008] An aspect of the present invention aims to provide a lens unit and a camera module having a sealing structure for taking countermeasures against corrosion caused by water intrusion.

Means for Solving the Problems

[0009] In order to solve the above problems, a lens unit according to an aspect of the present invention is a lens unit including a lens barrel and a lens held by the lens barrel, the lens including a first lens disposed closest to the object side, a first sealing member disposed over the entire periphery of the first lens on the object side of the first lens, a second sealing member different from the first sealing member disposed over the entire periphery of the first lens on the image side of the first lens, and a retainer that presses in the axial direction of the lens barrel to fix the lens.

[0010] In order to solve the above problems, a camera module according to an aspect of the present invention includes the above-described lens unit and an imaging element.

Effects of the Invention

[0011] According to an aspect of the present invention, it is possible to provide a lens unit and a camera module having a sealing structure for taking countermeasures against corrosion caused by water intrusion.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0013] 〔Embodiment 1〕 [Configuration of Lens Unit] Hereinafter, an embodiment of the present invention will be described in detail. FIG. 1 is a cross-sectional view schematically showing the configuration of the lens unit according to Embodiment 1 of the present invention. Note that the details of the optical systems of the respective lenses included in the lens unit are omitted from the illustration.

[0014] As shown in FIG. 1, the lens unit 101A has at least lenses L1 to L5, a lens barrel 2A, spacers S1 to S5, a first sealing member 3, a second sealing member 4, a retainer 5, and a filter 6.

[0015] <Lens Barrel> The lens barrel 2A integrally includes a first barrel portion 2a, a stepped portion 2b, and a second barrel portion 2c in this order from the image plane side. The first barrel portion 2a is a portion on the image plane side of the stepped portion 2b. The stepped portion 2b is a portion that expands outward along a direction intersecting the axis of the first barrel portion 2a (for example, a direction perpendicular to the axis). The second barrel portion 2c is a portion that continues from the stepped portion 2b to the object side and has a larger diameter than the first barrel portion 2a.

[0016] The lens barrel 2A holds lenses L1 to L5 inside the barrel. The lens L1 is the lens located closest to the object side (front lens). The lens L1 is held in the second barrel portion 2c. Hereinafter, the lenses L2 to L5 are held in the first barrel portion 2a in this order from the object side toward the image plane side. FIG. 1 shows the optical axes X of the lenses L1 to L5. Note that the optical axis X is located on the same line as the axis of the lens barrel 2A.

[0017] The lens barrel 2A is made of resin as an example. The resin is, for example, a resin capable of insert molding with a conductive member (a wiring as an example). In this case, the resin may be one type or more than one type. Examples of such resin materials include super engineering plastics such as LENZE (registered trademark) and polyphenylene sulfide (PPS). In addition to the resin material, additives such as a plasticizer, an ultraviolet absorber, a light stabilizer, and a filler may be included. In-vehicle lenses are used for applications related to the safety and comfort of passengers in vehicle operations such as autonomous driving, driver assistance, and peripheral monitoring. Therefore, high reliability is required for in-vehicle lenses. Thus, the lens barrel 2A may be made using super engineering plastics that have high heat resistance, durability, and dimensional stability, and also have a lower manufacturing cost compared to metal parts and are suitable for mass production.

[0018] Note that the lens barrel 2A is not limited to being made of resin and may be made of metal.

[0019] A concave groove 2bT is provided along the outer peripheral edge of the stepped portion 2b. A part of a second sealing member 4 described later fits into the concave groove 2bT.

[0020] On the image side of the first barrel portion 2a, a lens reference plane is provided, which holds the lenses L1 to L5 and the filter 6.

[0021] <Lens> The lenses L1 to L5 are held in the above-described portion of the lens barrel 2A. The lens L1 is the lens (first lens) located closest to the object side. In the present embodiment, five lenses are provided, but the number of lenses included in the lens unit is not particularly limited. Only the lens L1 may be provided.

[0022] The materials of the lenses L1 to L5 have sufficient light transmittance, and may be one kind or more. The materials of the lenses L1 to L5 can be appropriately determined from viewpoints such as being suitable for low cost and mass production. Examples of the materials of the lenses L1 to L5 include glass, acrylic resin, polystyrene resin, polycarbonate resin, and polyolefin.

[0023] On the object side surface of the lens L1 (first lens), a chamfered object side stepped portion L1a is provided over the entire periphery.

[0024] <Spacer> The spacers S1 to S5 are annular structures arranged between adjacent lenses. Specifically, the spacer S1 is arranged between the lens L1 (first lens) and the lens L2. Also, the spacer S2 is arranged between the lens L2 and the lens L3. Also, the spacer S3 is arranged between the lens L3 and the lens L4. Also, the spacer S4 is arranged between the lens L4 and the lens L5. Also, the spacer S5 is arranged between the lens L5 and the filter 6. The spacers S1 to S5 can be realized using well-known spacer materials.

[0025] <Retainer> The retainer 5 abuts against the peripheral edge of the lens L1 from the object side and presses in the axial direction of the lens barrel 2A to fix the lenses L1 to L5 and the filter 6 to the lens barrel 2A.

[0026] An opening 5k centered on the optical axis X is provided on the object side of the retainer 5, and light can enter the optical surface on the object side of the lens L1 through the opening 5k.

[0027] The retainer 5 has, for example, a first threaded portion on its inner peripheral surface, and is fixed to the lens barrel 2A by screwing the first threaded portion into a second threaded portion formed at the object-side end of the outer peripheral surface of the lens barrel 2A. The retainer 5 presses against the peripheral edge of the lens L1 and is in close contact with the peripheral edge. More specifically, the region of the retainer 5 on the lens L1 side includes a lens contact portion that contacts the object-side surface of the lens L1 and a seal member contact portion that contacts the first seal member 3.

[0028] The retainer 5 can be paraphrased as a lens cap that presses the lens L1 in the axial direction. The retainer 5 is made of resin or metal.

[0029] <First seal member> The first seal member 3 is a seal member arranged over the entire periphery of the lens L1 (first lens) on the object side of the lens L1 (first lens). The first seal member 3 is sandwiched between the above-described seal member contact portion of the retainer 5 and the stepped portion L1a on the object side of the lens L1 (first lens). The first seal member 3 is a ring-shaped structure centered on the optical axis center and is arranged along the periphery of the lens L1 (first lens). The first seal member 3 is crushed when the retainer 5 is fixed to the lens barrel 2A, and is a member that liquid-tightly seals between the opening 5k side of the retainer 5 and the lens barrel 2A side with the first seal member 3 as a boundary. The first seal member 3 can be constituted by an O-ring.

[0030] The material of the first sealing member 3 is not particularly limited, and EPDM (ethylene propylene rubber), NBR (nitrile rubber), VMQ (silicone rubber), etc. can be used. Among them, from the viewpoints of the operating temperature range, weather resistance, water resistance, and chemical resistance, it is preferable to use EPDM.

[0031] In the example of FIG. 1, the first sealing member 3 does not contact the inner peripheral surface of the second cylindrical portion 2c of the lens barrel 2A. However, the present invention is not limited to this example, and the first sealing member 3 may contact the inner peripheral surface of the second cylindrical portion 2c of the lens barrel 2A. By closely adhering to any of the inner peripheral surface of the second cylindrical portion 2c of the lens barrel 2A, the retainer 5, and the lens L1, a more reliable seal can be achieved.

[0032] <Second Sealing Member> The second sealing member 4 is a sealing member arranged over the entire periphery of the lens L1 (first lens) on the image side of the lens L1 (first lens). The second sealing member 4 is located at the corner between the stepped portion 2b and the second cylindrical portion 2c in the lens barrel 2A. The second sealing member 4 is in close contact with the inner peripheral surface of the second cylindrical portion 2c, the surface of the stepped portion 2b, and the image-side peripheral portion of the lens L1 over the entire circumference, and seals the space between the lens barrel 2A and the lens L1 in a liquid-tight manner. The second sealing member 4 is separate from the first sealing member 3. Also, between the first sealing member 3 and the second sealing member 4, they are completely separated at the portion where the lens L1 contacts the lens barrel 2A.

[0033] Similar to the first sealing member 3, the second sealing member 4 is also a ring-shaped structure centered on the optical axis X and is arranged along the periphery of the lens L1 (first lens). Similar to the first sealing member 3, when the retainer 5 is fixed to the lens barrel 2A, the second sealing member 4 is crushed between the image side of the lens L1 and the stepped portion 2b. As a result, the second sealing member 4 is in close contact with the inner peripheral surface of the second cylindrical portion 2c, the surface of the stepped portion 2b, and the image-side peripheral portion of the lens L1 over the entire circumference, and seals the space between the lens barrel 2A side and the optical axis X side in a liquid-tight manner with the second sealing member 4 as a boundary. The second sealing member 4 can also be constituted by an O-ring.

[0034] As the material of the second sealing member 4, it can be composed of the same material as that of the first sealing member 3. Making them of the same material is preferable from the viewpoints of management and precipitation. However, the second sealing member 4 and the first sealing member 3 may be composed of different materials.

[0035] <Filter> As the filter 6, a well-known filter having optical characteristics can be adopted and arranged on the image side of the lens unit. For example, an IR cut filter, a polarizing filter, an ND filter, a band-pass filter, etc. can be adopted as the filter 6.

[0036] [Manufacture of Lens Unit] As an assembling method of the lens unit 101A, prepare the lens barrel 2A, insert the filter 6 from the opening on the object side of the lens barrel 2A and arrange it on the image side, and then alternately insert the spacers S5 to S1 and the lenses L5 to L2 in the order shown in FIG. 1. Then, fit the second sealing member 4 into the concave groove 2bT of the exposed stepped portion 2b. Note that the arrangement timing of the second sealing member 4 is not limited to this timing and may be performed at an earlier stage.

[0037] Next, arrange the lens L1 (the first lens) in the second cylindrical portion 2c, and arrange the first sealing member 3 on the stepped portion L1a on the object side of the lens L1. Then, fix the retainer 5 to the lens barrel 2A.

[0038] The lens unit 101A can be assembled by the above method.

[0039] [Configuration of Camera Module] FIG. 2 is a diagram schematically showing the configuration of the camera module according to the present embodiment. As shown in FIG. 2, the camera module 100 has a lens unit 101A, a casing 102, and an imaging element 103. The camera module 100 is used for an in-vehicle camera.

[0040] The casing 102 is a housing and has an opening into which the lens barrel 2A of the lens unit 101A is inserted. The lens unit 101A is inserted into the opening and is fixed to the casing 102 in a state where it abuts against the opening edge of the casing 102 at the stepped portion of the lens barrel 2A.

[0041] The imaging element 103 is fixed at a position on the bottom of the casing 102 that is centered on the axis of the lens barrel 2A. The imaging element 103 is an image sensor and examples thereof include a CMOS (Complementary Metal Oxide Semiconductor) camera and a CCD (Charge Coupled Device) camera.

[0042] The camera module 100 further includes various configurations for operating the lens unit 101A. For example, the camera module 100 can further include wiring and a power source (not shown).

[0043] As described above, according to the configuration of the lens unit 101A of the present embodiment, a first sealing member 3 disposed over the entire periphery of the lens L1 on the object side of the lens L1, and a second sealing member 4 different from the first sealing member 3 disposed over the entire periphery of the lens L1 on the image side of the lens L1 are provided. Thereby, even when water enters from the object side of the lens unit 101A into the lens barrel 2A, the double sealing function of the first sealing member 3 and the second sealing member 4 is effective, and the configuration is such that it is difficult for water to enter the image side of the lens L1. Further, even if corrosion occurs in the vicinity of the first sealing member, by having the second sealing member 4 different from the first sealing member 3 on the image side of the lens L1, it is possible to block water from entering the image side of the lens L1.

[0044] 〔Embodiment 2〕 Another embodiment of the present invention will be described below. For convenience of explanation, members having the same functions as those described in the above embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.

[0045] FIG. 3 is a cross-sectional view schematically showing the configuration of the lens unit 101B according to Embodiment 2 of the present invention. In the lens unit 101B of the present embodiment, a chamfered image-side stepped portion L1b is provided over the entire periphery of the image-side surface of the lens L1 (first lens). In this regard, it is different from the lens unit 101A of Embodiment 1. Also, in the lens unit 101B of the present embodiment, the lens barrel 2B has the same diameter (inner diameter) in the optical axis direction. In this regard as well, it is different from the lens unit 101A of Embodiment 1.

[0046] Specifically, the lens barrel 2B has a configuration with the same diameter, and the lens L1 (first lens) and the other lenses L2 to L5 have the same diameter (outer diameter). Also, the spacers S1 to S5 are the same diameter as the lenses L1 to L5.

[0047] The lens unit 101B is the same as Embodiment 1 in that a chamfered object-side stepped portion L1a is provided over the entire periphery of the object-side surface of the lens L1 (first lens), but is different from Embodiment 1 in that a chamfered image-side stepped portion L1b is also provided over the entire periphery of the image-side surface of the lens L1 (first lens).

[0048] The second sealing member 4 is arranged to fit into the stepped portion L1b on the image side of the lens L1. Here, the spacer S1 disposed between the lens L1 and the lens L2 abuts against the surface on the image plane side of the lens L1 and the surface on the object side of the lens L2, defining the interval therebetween as a predetermined interval. The second sealing member 4 is in close contact between the inner surface of the groove constituting the stepped portion L1b on the image side of the lens L1 and the inner surface of the lens barrel 2B in a state where such a predetermined interval is realized, and seals it in a liquid-tight manner. To realize this, the length of the second sealing member 4 along the optical axis is preferably longer than the width of the stepped portion L1b (the width of the groove along the direction perpendicular to the optical axis) of the image-side stepped portion L1b in a state where the retainer 5 is not yet fixed to the lens barrel 2B. In other words, in this state, it is preferable that the second sealing member 4 is slightly larger than the width of the stepped portion of the lens L1. Thereby, when the retainer 5 is completely fixed to the lens barrel 2B, the second sealing member 4 is pushed between the stepped portion L1b on the image plane side of the lens L1 and the inner surface of the lens barrel 2B, enabling good sealing.

[0049] As described above, according to the lens unit 101B of the present embodiment, even in the aspect of the same lens diameter that was inconvenient in the prior art, it is possible to satisfactorily prevent the intrusion of water.

[0050] 〔Embodiment 3〕 Another embodiment of the present invention will be described below. For the sake of convenience of explanation, members having the same functions as the members described in the above embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.

[0051] FIG. 4 is a cross-sectional view schematically showing the configuration of a lens unit 101C according to Embodiment 3 of the present invention. The lens unit 101C of the present embodiment is different from Embodiment 1 in that a gasket first sealing member 3C is employed instead of the O-ring first sealing member 3 of Embodiment 1.

[0052] Further, the lens unit 101C of the present embodiment is different from Embodiment 1 in that a gasket second sealing member 4C is employed instead of the O-ring second sealing member 4 of Embodiment 1.

[0053] As shown in Fig. 4, the gaskets of the first sealing member 3C and the second sealing member 4C have a square cross section. The first sealing member 3C has a rectangular cross section, and the major axis extends along a direction perpendicular to the optical axis. As shown in Fig. 4, the first sealing member 3C and the second sealing member 4C may have different gasket widths, and any size may be used as long as it is suitable for the installation location of the lens barrel 2A.

[0054] As the gasket, a gasket made of a well-known gasket material can be used. The material of the gasket (second sealing member 4C) is not particularly limited, and EPDM (ethylene propylene rubber), NBR (nitrile rubber), VMQ (silicone rubber), etc. can be used. Among them, from the viewpoints of the use temperature range, weather resistance, water resistance, and chemical resistance, it is preferable to use EPDM.

[0055] 〔Embodiment 4〕 Other embodiments of the present invention will be described below. For the sake of convenience of explanation, members having the same functions as those described in the above embodiments are denoted by the same reference numerals, and the description thereof will not be repeated.

[0056] Fig. 5 is a cross-sectional view schematically showing the configuration of a lens unit 101D according to Embodiment 4 of the present invention. The lens unit 101D of the present embodiment is different from Embodiment 1 in that a first sealing member 3C of a gasket is adopted instead of the first sealing member 3 of the O-ring in Embodiment 1. The second sealing member 4 is the second sealing member 4 of the O-ring, similar to that in Embodiment 1.

[0057] As shown in Fig. 5, by making the sealing members arranged on the object side and the image side of the lens L1 be sealing members with different cross-sectional shapes, there are advantages such as improving the assemblability (assemblability considering the ease of twisting and insertion when fixing the retainer), or optimizing items such as the movement of the sealing member and liquid leakage when an external force is applied.

[0058] 〔Embodiment 5〕 Other embodiments of the present invention will be described below. For convenience of explanation, members having the same functions as those described in the above embodiments are denoted by the same reference numerals, and the description thereof will not be repeated.

[0059] FIG. 6 is a cross-sectional view schematically showing the configuration of a lens unit 101E according to Embodiment 5 of the present invention. The lens unit 101E of the present embodiment is different from the configuration of Embodiment 1 in that a sealing material 7 is disposed between the retainer 5 and the lens barrel 2A.

[0060] As shown in FIG. 6, the retainer 5 has an inner peripheral surface 5i facing the outer peripheral surface 2i of the lens barrel 2A. A screw structure is provided on the outer peripheral surface 2i of the lens barrel 2A and the inner peripheral surface 5i of the retainer 5, and they are configured to be screwed together. The sealing material 7 is disposed at a position close to the outside between the outer peripheral surface 2i of the lens barrel 2A and the inner peripheral surface 5i of the retainer 5. The sealing material 7 may be in the form of an O-ring or a packing, and liquid-tightly seals between the outer peripheral surface 2i of the lens barrel 2A and the inner peripheral surface 5i of the retainer 5. As the sealing material 7, a UV-curable (photo-curable) adhesive or a thermosetting adhesive can be employed. It is also possible to employ a composite type adhesive combining UV curing and thermosetting.

[0061] [Embodiment 6] Other embodiments of the present invention will be described below. For convenience of explanation, members having the same functions as those described in the above embodiments are denoted by the same reference numerals, and the description thereof will not be repeated.

[0062] FIG. 7 is a cross-sectional view schematically showing the configuration of a lens unit 101F according to Embodiment 6 of the present invention. The lens unit 101F of the present embodiment is different from Embodiment 1 in that it further includes an annular heater 8 (electrical functional component).

[0063] As shown in FIG. 7, the heater 8 is disposed at a position closer to the optical axis than the concave groove 2bT in the stepped portion 2b of the lens barrel 2A of the lens unit 101F. The heater 8 is provided with a power supply route (not shown). The heater 8 may be any well-known heater that can be mounted on the lens unit.

[0064] In this way, by disposing the heater 8 on the image side of the lens L1, it becomes possible to raise the temperature of the lens L1 by the heat of the heater 8.

[0065] In the present embodiment, an example in which the heater 8 is mounted has been described. However, the present invention is not limited to this, and an electric functional component may be installed at the installation location of the heater 8 described above. As an example, a cooler can be mentioned.

[0066] 〔Embodiment 7〕 Another embodiment of the present invention will be described below. For convenience of explanation, members having the same functions as the members described in the above embodiments are denoted by the same reference numerals, and the description thereof will not be repeated.

[0067] FIG. 8 is a cross-sectional view schematically showing the configuration of the lens unit 101G according to Embodiment 7 of the present invention. The lens unit 101G of the present embodiment is different in that the configuration of the lens barrel 2G is different from that of the lens barrel 2A of Embodiment 1.

[0068] The lens barrel 2G shown in FIG. 8 is configured to have the same diameter (inner diameter), and a lens reference surface 25 is provided at the end on the object side, and the diameter is reduced. The lens L1 (first lens) is supported by the lens reference surface 25. The end on the image side of the lens barrel 2G has an image-side opening that is the same as or wider than that of the lenses L1 to L5 (having the same outer diameter).

[0069] Note that the first sealing member 3G shown in FIG. 8 employs the first sealing member 3C of the gasket, similar to Embodiment 3.

[0070] The lenses L1 to L5, etc. are assembled into the lens barrel 2G from the image side opening. In FIG. 8, the components are inserted into the lens barrel 2G from the lower side to the upper side of the drawing. Specifically, after preparing the lens barrel 2G, first, the first sealing member 3C is inserted into the lens barrel 2G from the image side opening and arranged in the groove formed between the lens reference surface 25 and the inner peripheral surface of the lens barrel 2G. Next, the lens L1 (first lens) is inserted into the lens barrel 2G from the image side opening. The lens L1 is provided with an object side stepped portion L1a, and the first sealing member 3C and the tip of the lens reference surface 25 are configured to abut against the object side stepped portion L1a.

[0071] Next, the second sealing member 4 is inserted into the lens barrel 2G from the image side opening and arranged at the image side stepped portion L1b of the lens L1. Thereafter, as shown in FIG. 8, the spacers and the lenses are inserted alternately. After inserting the spacer S5, the filter 6 is inserted, and the image side opening of the lens barrel 2G is sealed with an image side retainer 50 (retainer) which is a pressing ring. A screw structure that can be screwed together is provided on the inner peripheral surface of the image side opening of the lens barrel 2G and the outer peripheral surface of the image side retainer 50.

[0072] 〔Embodiment 8〕 Other embodiments of the present invention will be described below. For the sake of convenience of explanation, members having the same functions as those described in the above embodiments are denoted by the same reference numerals, and the description thereof will not be repeated.

[0073] FIG. 9 is a cross-sectional view schematically showing the configuration of the lens unit 101H according to Embodiment 8 of the present invention. The lens unit 101H of this embodiment is different in that the configuration of the lens barrel 2H is different from that of the lens barrel 2G of Embodiment 7.

[0074] As shown in FIG. 9, the lens barrel 2H of the lens unit 101H has a caulking structure portion 27 at the image-side opening. The lens barrel 2H is made of resin instead of metal in order to achieve caulking. When various components arranged inside the lens barrel are inserted into the lens barrel from the image-side opening, the caulking structure portion 27 stands up toward the image side. After the various components are inserted into the lens barrel from the image-side opening, the caulking structure portion 27 that has stood up toward the image side is bent toward the optical axis side as shown in FIG. 9, thereby fixing the lens and the like.

[0075] 〔Summary〕 As is apparent from the above description, the lens unit according to the first aspect of the present invention is a lens unit including a lens barrel and a lens held by the lens barrel, wherein the lens includes a first lens disposed on the most object side, a first sealing member disposed over the entire periphery of the first lens on the object side of the first lens, a second sealing member different from the first sealing member disposed over the entire periphery of the first lens on the image side of the first lens, and a retainer that presses in the axial direction of the lens barrel to fix the lens. According to the first aspect, even when water enters from the object side of the lens unit into the lens barrel, the double-structured sealing function of the first sealing member and the second sealing member is effective, and the configuration is such that it is difficult for water to enter on the image side of the first lens. Further, even if corrosion occurs in the vicinity of the first sealing member, by having a second sealing member different from the first sealing member on the image side of the first lens, it is possible to block water from entering on the image side of the first lens.

[0076] In the lens unit according to the second aspect of the present invention, in the first aspect, at least one of the first sealing member and the second sealing member may be an O-ring. According to the second aspect, it is possible to seal liquid-tightly with the O-ring.

[0077] In the lens unit according to the third aspect of the present invention, in the first aspect, at least one of the first sealing member and the second sealing member may be a gasket. According to the third aspect, it is possible to seal liquid-tightly with a gasket.

[0078] In the lens unit according to the fourth aspect of the present invention, in the first aspect, one of the first sealing member and the second sealing member may be an O-ring, and the other sealing member may be a gasket. According to the fourth aspect, it is possible to seal liquid-tightly each of the object side and the image side of the first lens with a gasket and an O-ring.

[0079] In the lens unit according to the fifth aspect of the present invention, in any one of the first aspect to the fourth aspect, on the peripheral edge on the image side of the first lens, a chamfered stepped portion is provided over the entire circumference of the peripheral edge of the first lens, and the second sealing member may be fitted into the stepped portion. According to the fifth aspect, on the peripheral edge on the image side of the first lens, a good sealing function can be exhibited without displacement of the second sealing member.

[0080] In the lens unit according to the sixth aspect of the present invention, in any one of the first aspect to the fifth aspect, the retainer has an inner peripheral surface facing the outer peripheral surface of the lens barrel, and a sealing material is further provided between the outer peripheral surface of the lens barrel and the inner peripheral surface of the retainer to seal between the outer peripheral surface of the lens barrel and the inner peripheral surface of the retainer. According to the sixth aspect, it is possible to prevent water from entering the lens barrel from the gap between the outer peripheral surface of the lens barrel and the inner peripheral surface of the retainer.

[0081] In the lens unit according to the seventh aspect of the present invention, in any one of the first aspect to the sixth aspect, the retainer may be a lens cap that presses the first lens in the axial direction. According to the seventh aspect, it is possible to seal with the first sealing member between the lens cap and the first lens.

[0082] In the lens unit according to the eighth aspect of the present invention, in any one of the first aspect to the seventh aspect, it may further include an electrical functional component. According to the eighth aspect, if a heater is mounted as the electrical functional component, for example, the temperature of the lens can be raised.

[0083] In the lens unit according to the ninth aspect of the present invention, in any one of the first aspect to the eighth aspect, the lens barrel is made of resin or metal, and the retainer may be made of resin or metal.

[0084] The camera module according to the tenth aspect of the present invention includes the lens unit according to any one of the first aspect to the ninth aspect and an imaging element. According to the eleventh aspect, a highly reliable in-vehicle camera can be provided.

[0085] According to such a configuration, it is possible to provide a lens unit suitable for an in-vehicle camera. As a result, it is expected that the environment for promoting automation such as autonomous driving of automobiles will be improved. Therefore, the present invention is expected to contribute to the achievement of the Sustainable Development Goals (SDGs) related to the expansion of technological innovation and the promotion of sustainable industrialization.

[0086] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

Explanation of Reference Numerals

[0087] 2A, 2B, 2G, 2H lens barrel 2bT concave groove 2i outer peripheral surface 3, 3C, 3G first sealing member 4, 4C second sealing member 5 retainer 5i inner peripheral surface 5k opening 6 filter 7 Sealing material 8 Heater (electrical functional component) 27 Crimping structure part 50 Image-side retainer 100 Camera module 101A, 101B, 101C, 101D, 101E, 101F, 101G, 101H Lens unit 102 Casing 103 Image sensor L1 First lens (lens) L1a Object-side stepped part L1b Image-side stepped part L2, L3, L4, L5 Lenses S1, S2, S3, S4, S5 Spacers

Claims

1. A lens unit including a lens barrel and a lens held by the lens barrel, wherein the lens includes a first lens disposed on the most object side, a first sealing member disposed over the entire periphery of the first lens on the object side of the first lens, a second sealing member different from the first sealing member disposed over the entire periphery of the first lens on the image side of the first lens, and a retainer that presses in the axial direction of the lens barrel to fix the lens. The lens unit further comprising.

2. The lens unit according to claim 1, wherein at least one of the first sealing member and the second sealing member is an O-ring.

3. The lens unit according to claim 1, wherein at least one of the first sealing member and the second sealing member is a gasket.

4. The lens unit according to claim 1, wherein one of the first sealing member and the second sealing member is an O-ring and the other is a gasket.

5. A chamfered stepped portion is provided over the entire periphery of the first lens at the periphery on the image side of the first lens, The lens unit according to claim 1, wherein the second sealing member can be fitted into the stepped portion.

6. The retainer has an inner peripheral surface facing the outer peripheral surface of the lens barrel, The lens unit according to claim 1, further comprising a sealing material disposed between the outer peripheral surface of the lens barrel and the inner peripheral surface of the retainer to seal between the outer peripheral surface of the lens barrel and the inner peripheral surface of the retainer.

7. The lens unit according to claim 1, wherein the retainer is a lens cap that presses the first lens in the axial direction.

8. The lens unit according to claim 1, further comprising an electrical functional component.

9. The lens barrel is made of resin or metal, The lens unit according to claim 1, wherein the retainer is made of resin or metal.

10. A camera module having the lens unit according to any one of claims 1 to 9 and an imaging element.

Images