Cemented lens and method of manufacturing the same

Abstract

This prevents the optical axes of the lenses from shifting. [Solution] The cemented lens 1 has a first lens 10 having a recess 12 formed on a surface 10A, and a second lens 20 having a convex portion 22 formed on a surface 20B, the surface 20B being cemented to the surface 10A of the first lens 10 via an adhesive layer 30, the convex portion 22 being located within the recess 12.

Description

[Technical Field]

[0001] The present invention relates to a cemented lens and a method for manufacturing the cemented lens. [Background technology]

[0002] Cemented lenses are known in which a plurality of lenses are bonded together with an adhesive. For example, Patent Document 1 describes that the lenses and the core are bonded together via a resin film. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-191260 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, it is preferable that the cemented lens is cemented so that the optical axes of the lenses do not shift. However, there is a risk that the optical axes of the lenses may shift if the lenses shift before the adhesive hardens, for example.

[0005] An object of the present invention is to provide a cemented lens that can prevent misalignment of the optical axes of the lenses and a method for manufacturing the cemented lens. [Means for solving the problem]

[0006] A cemented lens according to the present disclosure includes a first lens having a concave portion formed on a first principal surface, and a second lens having a convex portion formed on a second principal surface, the second principal surface being cemented to the first principal surface of the first lens via an adhesive layer, the convex portion being located within the concave portion.

[0007] A method for manufacturing a cemented lens according to the present disclosure includes applying an adhesive to at least one of a first main surface of a first lens on which a concave portion is formed and a second main surface of a second lens on which a convex portion is formed; bonding the first main surface of the first lens and the second main surface of the second lens via the adhesive while inserting the convex portion into the concave portion; and curing the adhesive to bond the first main surface and the second main surface together, thereby manufacturing the cemented lens. [Effects of the Invention]

[0008] According to the present invention, it is possible to prevent the optical axes of the lenses from shifting from one another. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view of a cemented lens according to this embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view of the first lens. [Figure 3] FIG. 3 is a schematic diagram for explaining the shape of the recessed portion. [Figure 4] FIG. 4 is a schematic cross-sectional view of the second lens. [Figure 5] FIG. 5 is a schematic diagram for explaining the shape of the convex portion. [Figure 6] FIG. 6 is a schematic diagram illustrating a method for manufacturing the cemented lens according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments, and when there are multiple embodiments, the present invention also includes configurations that combine the various embodiments. Numerical values ​​include rounded-off ranges. Numerical ranges expressed as "to" refer to a range that includes the numbers before and after "to" as the lower and upper limits, and the same meaning will be used hereinafter.

[0011] (cemented lens) FIG. 1 is a schematic cross-sectional view of a cemented lens according to this embodiment. The cemented lens 1 is a lens that transmits visible light. As shown in FIG. 1, the cemented lens 1 according to this embodiment is an optical member formed by bonding a first lens 10 and a second lens 20 together via an adhesive layer 30. If the direction along the optical axis AX of the cemented lens 1 is defined as the Z direction, the cemented lens 1 has the second lens 20 and the first lens 10 laminated in this order in the Z direction, and a surface 20B (second main surface) of the second lens 20 in the Z direction and a surface 10A (first main surface) of the first lens 10 opposite to the Z direction are bonded together via the adhesive layer 30. In the cemented lens 1, the first lens 10 and the second lens 20 are bonded together with a convex portion 22 of the second lens 20 positioned within a concave portion 12 (described below) of the first lens 10. As a result, the first lens 10 and the second lens 20 are cemented together with the optical axis AX1 of the first lens 10 and the optical axis AX2 of the second lens 20 aligned. In this embodiment, the optical axis AX1 of the first lens 10 and the optical axis AX2 of the second lens 20 coincide with the optical axis AX1 of the cemented lens 1.

[0012] The cemented lens 1 has a circular shape when viewed from the Z direction, and in this embodiment has a cylindrical shape, but the shape of the cemented lens 1 is not limited to this and may be any shape.

[0013] The diameter A0 of the cemented lens 1 is preferably 2.0 mm or more and 4.6 mm or less, more preferably 2.1 mm or more and 2.8 mm or less, and even more preferably 2.2 mm or more and 2.3 mm or less. According to this embodiment, even in such a relatively small cemented lens, misalignment of the optical axes of the lenses can be appropriately suppressed. Here, the diameter A0 refers to the diameter of the cemented lens 1 when viewed in the Z direction, and refers to the diameter at the point where the outer diameter is greatest (for example, the outermost diameter when the cemented lens 1 is projected in the Z direction). If the cemented lens 1 is not circular when viewed in the Z direction, the diameter A0 may refer to the length of the longest straight line connecting any two points on the periphery of the cemented lens 1.

[0014] In this embodiment, the cemented lens 1 has a configuration in which two lenses, a first lens 10 and a second lens 20, are stacked (cemented) in the Z direction, but is not limited to this and may have a configuration in which three or more lenses are stacked in the Z direction. In this case, it is preferable that either a concave portion 12 or a convex portion 22, which will be described later, is formed on the cemented surfaces of the two lenses adjacent in the Z direction (surfaces 10A and 20B in the example of FIG. 1).

[0015] (1st lens) FIG. 2 is a schematic cross-sectional view of the first lens 10. FIG. 2 is a cross-sectional view of the first lens 10 taken along a cross section that overlaps with the optical axis AX1 of the first lens 10. The first lens 10 is a lens that transmits visible light. The first lens 10 has a circular shape when viewed from the Z direction, but is not limited to this and may have any shape when viewed from the Z direction. Furthermore, the first lens 10 is made of glass, but is not limited to this and may be made of resin.

[0016] The diameter A1 of first lens 10 is preferably 2.0 mm to 4.6 mm, more preferably 2.1 mm to 2.8 mm, and even more preferably 2.2 mm to 2.3 mm. According to this embodiment, when such a relatively small first lens 10 is cemented to another lens, misalignment of the optical axes of the lenses can be appropriately suppressed. Here, diameter A1 refers to the diameter of first lens 10 when viewed from the Z direction, and refers to the diameter at the point where the outer diameter is greatest (for example, the outermost diameter when first lens 10 is projected in the Z direction). Furthermore, if first lens 10 is not circular when viewed from the Z direction, diameter A1 may refer to the length of the longest straight line connecting any two points on the periphery of first lens 10.

[0017] As shown in FIG. 2, first lens 10 has surface 10A, which is the principal surface on the side opposite to the Z direction, and surface 10B, which is the principal surface on the Z direction side (the principal surface opposite surface 10A). As shown in FIG. 2, first lens 10 has curved surface 10A. In this embodiment, surface 10A has a convex shape that protrudes toward the side opposite to the Z direction, and first lens 10 can be said to be a convex lens. Surface 10A may be spherical or aspherical. Furthermore, in this embodiment, first lens 10 is a single-sided convex lens with surface 10B that is flat, but the present invention is not limited thereto. First lens 10 may be a double-sided convex lens with surface 10B that is convex, or a meniscal lens with surface 10B that is concave. Furthermore, first lens 10 is not limited to a lens having a convex surface 10A, and may be a concave lens having a concave surface 10A. That is, surface 10A on which recesses 12 (described later) are formed may be concave. In this case, surface 20B of second lens 20 is convex.

[0018] The root mean square roughness Rms of the surface 10A is preferably 0.005 μm or more and 0.03 μm or less, more preferably 0.006 μm or more and less than 0.02 μm, and even more preferably 0.007 μm or more and less than 0.01 μm. When the root mean square roughness Rms of the surface 10A is within this range, the surface 10A becomes smooth and the optical properties can be appropriately improved. The root mean square roughness Rms can be measured using a contact-type three-dimensional measuring device or the like.

[0019] (recess) As shown in FIG. 2, a recess 12 is formed on the surface 10A. The recess 12 is a depression formed on the surface 10A. In this embodiment, the recess 12 is formed at the center position of the surface 10A when viewed from the Z direction. That is, the recess 12 is formed at a position overlapping with the optical axis AX1. By forming the recess 12 at a position overlapping with the optical axis AX1, the recess 12 can be easily formed when manufacturing the first lens 10. Furthermore, by forming the recess 12 at a position overlapping with the optical axis AX1, the influence on the optical characteristics of the first lens 10 can be reduced. However, the recess 12 is not limited to being formed at a position overlapping with the optical axis AX1, and may be formed radially outward from the position overlapping with the optical axis AX1 (the center position of the surface 10A) when viewed from the Z direction.

[0020] The recess 12 is a conical depression. By making the recess 12 a conical depression, the recess 12 can be easily formed when manufacturing the first lens 10. Furthermore, by making the recess 12 a conical depression, the convex portion 22 of the second lens 20, which will be described later, can be easily inserted, and deviation of the optical axis can be appropriately suppressed. However, the shape of the recess 12 is not limited to a conical shape and may be any shape.

[0021] Fig. 3 is a schematic diagram illustrating the shape of the recesses. Fig. 3 is a partial enlarged view of the surface 10A. As shown in Fig. 3, the depth D1 of the recesses 12 is preferably 0.005 μm or more and 0.03 μm or less, more preferably 0.006 μm or more and less than 0.02 μm, and even more preferably 0.007 μm or more and less than 0.01 μm. By setting the depth D1 within this range, the influence on the optical properties of the first lens 10 can be reduced, and the convex portion 22 of the second lens 20 can be appropriately inserted, thereby appropriately suppressing misalignment of the optical axis. Furthermore, the width W1 of the recess 12 is preferably 0.1 mm or more and less than 0.5 mm, more preferably 0.1 mm or more and less than 0.3 mm, and even more preferably 0.1 mm or more and 0.2 mm or less. By keeping the width W1 within this range, it is possible to appropriately insert the protrusion 22 of the second lens 20 while minimizing the effect on the optical properties of the first lens 10, thereby appropriately suppressing misalignment of the optical axis. Furthermore, it is preferable that width W1 is longer than depth D1. The ratio of depth D1 to width W1 (D1 / W1) is preferably 0.001% or more and 0.025% or less, more preferably 0.001% or more and 0.01% or less, and even more preferably 0.001% or more and 0.003% or less. By having the ratio of depth D1 to width W1 within this range, it is possible to appropriately insert convex portion 22 of second lens 20 while minimizing the effect on the optical characteristics of first lens 10, thereby appropriately suppressing misalignment of the optical axis.

[0022] The depth D1 and width W1 can be measured based on a fitting curve L1 of the surface 10A. The fitting curve L1 of the surface 10A is a quadratic curve obtained by approximating a profile line PL1, which connects the profiles at each radial position on the surface 10A and passes through the position where the recess 12 is formed (the center position of the surface 10A in this example), with a quadratic equation. That is, the fitting curve L1 of the surface 10A is obtained by measuring the profiles (positions in the Z direction) at each radial position on the surface 10A from an end 10A1 on one side of the radial direction of the surface 10A, which passes through the position where the recess 12 is formed (the center position of the surface 10A in this example), to an end 10A2 on the other side of the radial direction of the surface 10A, and then approximating the profile line PL1 connecting these profiles with a quadratic curve. The profile at each radial position on the surface 10A can be measured using a contact-type three-dimensional measuring device or the like.

[0023] In this case, the maximum value of the distance in the Z direction between the profile line PL1 and the fitting curve L1 in the region including the location where the recess 12 is formed (for example, a region with a diameter of 1 mm centered on the center position of the surface 10A) can be set to the depth D1. Furthermore, among the positions on the profile line PL1 where the Z coordinate (position in the Z direction) of the profile line PL1 is on the opposite side of the Z direction from the Z coordinate (position in the Z direction) of the fitting curve L1, the position on one radial side of the position where the depth D1 was measured and closest to the position where the depth D1 was measured is designated as position P1A. Similarly, among the positions on the profile line PL1 where the Z coordinate of the profile line PL1 is on the opposite side of the Z direction from the Z coordinate of the fitting curve L1, the position on the other radial side of the position where the depth D1 was measured and closest to the position where the depth D1 was measured is designated as position P1B. In this case, the radial length from position P1A to position P1B can be designated as width W1.

[0024] Note that any method may be used to form recesses 12 on surface 10A. For example, when molding first lens 10 using a mold, recesses 12 can be formed by molding by forming convex portions of a shape corresponding to recesses 12 on the surface of the mold that forms surface 10A. However, the method is not limited to this, and recesses 12 may also be formed by machining surface 10A.

[0025] (Second lens) FIG. 4 is a schematic cross-sectional view of the second lens 20. FIG. 4 is a cross-sectional view of the second lens 20 taken along a cross section that overlaps with the optical axis AX2 of the second lens 20. The second lens 20 is a lens that transmits visible light. The second lens 20 has a circular shape when viewed from the Z direction, but is not limited to this and may have any shape when viewed from the Z direction. The second lens 20 is made of glass. However, the second lens 20 is not limited to this and may be made of resin. The second lens 20 is preferably made of a material that has optical properties different from those of the first lens 10. The optical properties here may refer to at least one of refractive index and dispersion.

[0026] The diameter A2 of the second lens 20 is preferably 2.0 mm to 4.6 mm, more preferably 2.1 mm to 2.8 mm, and even more preferably 2.2 mm to 2.3 mm. According to this embodiment, when such a relatively small second lens 20 is cemented to another lens, misalignment of the optical axes of the lenses can be appropriately suppressed. Here, the diameter A2 refers to the diameter of the second lens 20 when viewed from the Z direction, and refers to the diameter at the point where the outer diameter is greatest (for example, the outermost diameter when the second lens 20 is projected in the Z direction). Furthermore, if the second lens 20 is not circular when viewed from the Z direction, the diameter A2 may refer to the length of the longest straight line connecting any two points on the periphery of the second lens 20.

[0027] As shown in FIG. 4, second lens 20 has surface 20A, which is the principal surface on the opposite side to the Z direction, and surface 20B, which is the principal surface on the Z direction side (the principal surface opposite surface 20A). As shown in FIG. 4, second lens 20 has curved surface 20B. In this embodiment, surface 20B has a concave shape recessed on the opposite side to the Z direction, and second lens 20 can be said to be a concave lens. Surface 20B may be spherical or aspherical. Furthermore, in this embodiment, second lens 20 is a single-sided concave lens with flat surface 20A, but is not limited thereto. Second lens 20 may be a double-sided concave lens with concave surface 20A, or a meniscal lens with convex surface 20A. It is preferable that the curvature of surface 20B is the same as or close to the curvature of surface 10A of first lens 10. Here, "close to each other in curvature" may mean that the difference between the two curvatures is within 5% of the curvature of surface 10A. Furthermore, second lens 20 is not limited to having surface 20B with a concave shape, and may be a convex lens with surface 20B with a convex shape. That is, surface 20B on which convex portions 22 described below are formed may be convex. In this case, surface 10A of first lens 10 is concave.

[0028] The root mean square roughness Rms of surface 20B is preferably 0.005 μm or more and 0.03 μm or less, more preferably 0.006 μm or more and less than 0.02 μm, and even more preferably 0.007 μm or more and less than 0.01 μm. When the root mean square roughness Rms of surface 20B is within this range, surface 20B becomes smooth and optical properties can be appropriately improved. The root mean square roughness Rms can be measured using a contact-type three-dimensional measuring device or the like.

[0029] (Convex part) 4, a convex portion 22 is formed on surface 20B. Convex portion 22 is a protrusion formed on surface 29B. Convex portion 22 is formed integrally with other portions of second lens 20, and is not attached to other portions of second lens 20 afterward. In this embodiment, the convex portion 22 is formed at the center position of the surface 20B when viewed from the Z direction. That is, the convex portion 22 is formed at a position overlapping with the optical axis AX2. By forming the convex portion 22 at a position overlapping with the optical axis AX2, the convex portion 22 can be easily formed when manufacturing the second lens 20. Furthermore, by forming the convex portion 22 at a position overlapping with the optical axis AX2, it is possible to reduce the influence on the optical characteristics of the second lens 20. However, the convex portion 22 is not limited to being formed at a position overlapping with the optical axis AX2, and may be formed radially outward from the position overlapping with the optical axis AX2 when viewed from the Z direction (the center position of the surface 20B).

[0030] The convex portion 22 is a conical protrusion. By forming the convex portion 22 as a conical depression, the convex portion 22 can be easily formed when manufacturing the second lens 20. Furthermore, by forming the convex portion 22 into a conical shape, it can be easily inserted into the recess 12 of the first lens 10, and misalignment of the optical axis can be appropriately suppressed. However, the shape of the convex portion 22 is not limited to a conical shape and may be any shape.

[0031] Fig. 5 is a schematic diagram illustrating the shape of the convex portion. Fig. 5 is a partial enlarged view of surface 20B. As shown in Fig. 5, height D2 of convex portion 22 is preferably 0.005 μm or more and 0.03 μm or less, more preferably 0.006 μm or more and less than 0.02 μm, and even more preferably 0.007 μm or more and less than 0.01 μm. By setting height D2 within this range, the influence on the optical properties of second lens 20 can be reduced, and the convex portion can be appropriately inserted into concave portion 12 of first lens 10, thereby appropriately suppressing misalignment of the optical axis. Furthermore, the width W2 of the convex portion 22 is preferably 0.1 mm or more and less than 0.5 mm, more preferably 0.1 mm or more and less than 0.3 mm, and even more preferably 0.1 mm or more and 0.2 mm or less. By setting the width W2 within this range, the influence on the optical characteristics of the second lens 20 can be reduced, and the convex portion 22 can be appropriately inserted into the concave portion 12 of the first lens 10, thereby appropriately suppressing misalignment of the optical axis. Furthermore, it is preferable that the width W2 is longer than the height D2. The ratio of the height D2 to the width W2 (D2 / W2) is preferably 0.001% or more and 0.025% or less, more preferably 0.001% or more and 0.01% or less, and even more preferably 0.001% or more and 0.003% or less. By having the ratio of the height D2 to the width W2 within this range, it is possible to minimize the effect on the optical properties of the second lens 20, while allowing the second lens 20 to be appropriately inserted into the recess 12 of the first lens 10, thereby appropriately suppressing misalignment of the optical axis. It is preferable that the height D2 of the protrusion 22 is equal to or less than the depth D1 of the recess 12. Similarly, it is preferable that the width W2 of the protrusion 22 is equal to or less than the width W2 of the recess 12. This allows the protrusion 22 to be properly inserted into the recess 12.

[0032] The height D2 and width W2 can be measured based on a fitting curve L2 of the surface 20B. The fitting curve L2 of the surface 20B is a quadratic curve obtained by approximating, with a quadratic equation, a profile line PL2 that connects the profiles at each position in the radial direction of the surface 20B and passes through the position where the protrusion 22 is formed (the center position of the surface 20B in this example). That is, the fitting curve L2 of the surface 20B is obtained by measuring the profiles (positions in the Z direction) at each position on the surface 20B along the radial direction from an end 20B1 on one side of the radial direction of the surface 20B, passing through the position where the protrusion 22 is formed (the center position of the surface 20B in this example), to an end 20B2 on the other side of the radial direction of the surface 20B, and then approximating, with a quadratic curve, the profile line PL2 that connects these profiles.

[0033] In this case, the maximum value of the distance in the Z direction between the profile line PL2 and the fitting curve L2 in the region including the location where the convex portion 22 is formed (for example, a region with a diameter of 1 mm centered on the center position of the surface 20B) can be set to the height D2. Furthermore, among the positions on the profile line PL2 where the Z coordinate of the profile line PL2 is on the opposite side of the Z direction from the Z coordinate of the fitting curve L2, the position on one radial side of the position where the height D2 was measured and closest to the position where the height D2 was measured is designated as position P2A. Similarly, among the positions on the profile line PL2 where the Z coordinate of the profile line PL2 is on the opposite side of the Z direction from the Z coordinate of the fitting curve L2, the position on the other radial side of the position where the height D2 was measured and closest to the position where the height D2 was measured is designated as position P2B. In this case, the radial length from position P2A to position P2B can be designated as width W2.

[0034] Note that any method may be used to form convex portions 22 on surface 20B. For example, when molding second lens 20 using a mold, convex portions 22 can be formed by molding by forming concave portions of a shape corresponding to convex portions 22 on the surface of the mold that forms surface 20B. However, the present invention is not limited to this, and convex portions 22 may also be formed by machining surface 20B.

[0035] (adhesive layer) The adhesive layer 30 is a layer provided between the surface 10A (cemented surface) of the first lens 10 and the surface 20B (cemented surface) of the second lens 20. The adhesive layer 30 is a layer formed by hardening an adhesive that bonds the surface 10A and the surface 20B together. The adhesive layer 30 transmits visible light. Any material that can bond the surface 10A and the surface 20B together while transmitting visible light may be used as the adhesive layer 30, but in this embodiment, the adhesive layer 30 is made of resin, and may be a curable resin that is cured by X-rays or heat, for example.

[0036] (Manufacturing method) Next, a method for manufacturing the cemented lens 1 will be described. FIG. 6 is a schematic diagram illustrating a method for manufacturing a cemented lens according to this embodiment. As shown in FIG. 6, in this manufacturing method, as shown in step S10 of FIG. 6, adhesive 30A, which is the adhesive layer 30 before curing, is applied to surface 20B of second lens 20 (step S10). Then, first lens 10 is placed on surface 20B of second lens 20 so that convex portion 22 of second lens 20 is inserted into concave portion 12 of first lens 10 and surface 20B is bonded to surface 10A via adhesive 30A (step S12). Then, adhesive 30A is cured to manufacture cemented lens 1 in which convex portion 22 is located in concave portion 12 and surface 20B is bonded to surface 10A via adhesive layer 30 (step S14). In step S10, adhesive 30A is applied to surface 20B of second lens 20, but this is not limiting, and adhesive 30A may be applied to surface 10A of first lens 10, and surface 20B may be bonded to surface 10A. Also, adhesive 30A may be applied to both surface 10A and surface 20B. That is, in step S10, adhesive 30A may be applied to at least one of surface 10A and surface 20B. Thus, according to this embodiment, the first lens 10 and the second lens 20 are bonded together with the convex portion 22 positioned within the concave portion 12, and therefore, by fitting the concave portion 12 into the convex portion 22, the first lens 10 and the second lens 20 can be bonded together in a positioned state.

[0037] (effect) As described above, the cemented lens 1 according to the first aspect of the present disclosure has a first lens 10 having a concave portion 12 formed on a surface 10A (first main surface) and a second lens 20 having a convex portion 22 formed on a surface 20B (second main surface). The surface 20B of the second lens 20 is cemented to the surface 10A of the first lens 10 via an adhesive layer 30, and the convex portion 22 is located within the concave portion 12. According to the present disclosure, first lens 10 and second lens 20 are bonded together with convex portion 22 positioned within concave portion 12, and therefore first lens 10 and second lens 20 are bonded together in a positioned state due to the fit between concave portion 12 and convex portion 22. Therefore, misalignment between optical axis AX1 of first lens 10 and optical axis AX2 of second lens 20 can be suppressed.

[0038] The cemented lens 1 according to the second aspect of the present disclosure is the cemented lens 1 according to the first aspect, and preferably, the concave portion 12 is formed at a position overlapping with the optical axis AX1 of the first lens 10, and the convex portion 22 is formed at a position overlapping with the optical axis AX2 of the second lens 20. By forming the concave portion 12 and the convex portion 22 at positions overlapping with the optical axes, the concave portion 12 and the convex portion 22 can be easily formed, and the effect on the optical properties of each lens can be reduced.

[0039] The cemented lens 1 according to the third aspect of the present disclosure is the cemented lens 1 according to the first or second aspect, and preferably the concave portion 12 is a conical depression and the convex portion 22 is a conical protrusion. By making the concave portion 12 and the convex portion 22 conical, the concave portion 12 can be easily formed and deviation of the optical axis can be appropriately suppressed.

[0040] The cemented lens 1 according to a fourth aspect of the present disclosure is the cemented lens 1 according to any one of the first to third aspects, and it is preferable that the recess 12 has a shape in which the width W1 is longer than the depth D1, and the protrusion 22 has a shape in which the width W2 is longer than the height D2. By using such shapes, it is possible to appropriately suppress deviation of the optical axis while minimizing the effect on the optical characteristics.

[0041] The cemented lens 1 according to a fifth aspect of the present disclosure is the cemented lens 1 according to any one of the first to fourth aspects, and it is preferable that the surface 10A of the first lens 10 is convex and the surface 20B of the second lens 20 is concave. By using such shapes, the recessed portions 12 and the protruding portions 22 can be easily formed.

[0042] The cemented lens 1 according to a sixth aspect of the present disclosure is the cemented lens 1 according to any one of the first to fifth aspects, and the first lens 10 and the second lens 20 are preferably made of glass. According to the present disclosure, it is possible to provide a cemented lens made of glass in which misalignment of the optical axis is suppressed.

[0043] A method for manufacturing a cemented lens according to a seventh aspect of the present disclosure includes applying adhesive 30A to at least one of surface 10A of first lens 10, where recess 12 is formed, and surface 20B of second lens 20, where convex portion 22 is formed, bonding surface 10A of first lens 10 and surface 20B of second lens 20 via adhesive 30A while inserting convex portion 22 into recess 12, and curing adhesive 30A to bond surface 10A and surface 20B to manufacture cemented lens 1. The present disclosure can provide cemented lens 1 in which misalignment of the optical axis is suppressed.

[0044] Although the embodiments of the present invention have been described above, the embodiments are not limited to the contents of these embodiments. Furthermore, the above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the scope of what is called equivalents. Furthermore, the above-described components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the above-described embodiments. [Explanation of symbols]

[0045] 1 cemented lens 10 First lens 10A Surface (first principal surface) 12 recess 20 Second lens 20B surface (2nd principal surface) 22 Convex part 30 Adhesive layer

Claims

1. a first lens having a recess formed on a first main surface; a second lens having a second main surface formed with a convex portion and bonded to the first main surface of the first lens via an adhesive layer; and The protrusion is located within the recess. Cemented lens.

2. the concave portion is formed at a position overlapping with the optical axis of the first lens, and the convex portion is formed at a position overlapping with the optical axis of the second lens, The cemented lens according to claim 1 .

3. The recessed portion is a conical depression, and the protruding portion is a conical protrusion. The cemented lens according to claim 1 or 2.

4. The recess has a shape in which the width is longer than the depth, and the protrusion has a shape in which the width is longer than the height. The cemented lens according to claim 1 or 2.

5. The first main surface of the first lens has a convex shape, and the second main surface of the second lens has a concave shape. The cemented lens according to claim 1 or 2.

6. The first lens and the second lens are made of glass. The cemented lens according to claim 1 or 2.

7. applying an adhesive to at least one of a first main surface of the first lens on which the recessed portion is formed and a second main surface of the second lens on which the protruding portion is formed; bonding a first main surface of the first lens and a second main surface of the second lens to each other via the adhesive while inserting the convex portion into the concave portion; curing the adhesive to bond the first principal surface and the second principal surface together to produce a cemented lens; Including, A method for manufacturing a cemented lens.

Images