Optical member, optical sensor, biological sensor, method for manufacturing optical member, method for manufacturing optical sensor, and method for manufacturing biological sensor

Abstract

To provide an optical member which includes a plurality of lenses and in which an optical path area of each lens optical system is easily and appropriately secured when the optical member has a configuration in which a plurality of light shielding parts are arranged in an optical axis direction corresponding to each lens.SOLUTION: An optical member 100 includes a lens portion 10 having a plurality of lenses 11 each having an optical axis along a first direction, and a light shielding portion 20 having a sheet shape and having a plurality of through holes provided at positions corresponding to respective optical axes OA of the plurality of lenses 11, wherein the light shielding portion 20 includes a first light shielding portion 21 relatively close to the lens portion 10 and a second light shielding portion 22 relatively far from the lens portion, and includes a wall-shaped body 31 located around the light shielding portion 20 and extending in the first direction (X1 to X2 direction). A connection part 30 connecting the first light shielding part 21 and the second light shielding part 22 is provided, and the connection part 30 is integrally formed with the light shielding part 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an optical member, an optical sensor including the optical member, and a biometric sensor, such as a fingerprint sensor, including the optical sensor. [Background technology]

[0002] Patent Document 1 discloses an optical sheet in which a metal reflective layer that reflects light is formed on a non-partial region of the flat surface opposite the lens surface of the lens array sheet. One example of a method for manufacturing this optical sheet includes the steps of: (1) forming a metal vapor deposition layer that is substantially light-transmitting on the flat surface opposite the lens surface of the lens array sheet; (2) forming a positive resist layer on the metal vapor deposition layer; (3) exposing the lens surface side of the lens array sheet through lenses; (4) developing the positive resist layer to peel and remove the photosensitive resist layer in the exposed areas; (5) etching the metal vapor deposition layer; and (6) peeling and removing the non-photosensitive resist layer in the unexposed areas, with a further step of metal plating the metal vapor deposition layer after step (6).

[0003] Patent Document 2 discloses a microlens array sheet in which a plurality of microlenses are two-dimensionally arranged on one surface of a transparent substrate. In this microlens array sheet, a metallic light-shielding layer pattern is formed on the other surface of the transparent substrate on which the microlenses are not arranged, the metallic light-shielding layer pattern being composed of a conductive metal light-shielding pattern, in which light-transmitting apertures are portions through which light irradiated from the microlens array surface passes and light-shielding portions are portions other than the microlens array surface, and a metal plating layer laminated on the conductive metal light-shielding pattern. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-65268 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-264351 Summary of the Invention [Problem to be solved by the invention]

[0005] In the optical members (optical sheets, microlens array sheets) disclosed in Patent Documents 1 and 2, the light-shielding portions (metal reflective layers and light-shielding patterns) are formed of materials different from the materials constituting the lenses. When an optical member includes multiple components made of different materials, the stresses accumulated in these components during the manufacturing process may differ from one another. In this case, the deformation behavior of each component differs when the stress accumulated in each component is relieved by heat applied during the manufacturing process. This makes it difficult to control the area of ​​the overlap between the optical surface of the lens and the opening of the light-shielding portion as viewed along the optical axis of the lens (the optical path area in the optical axis direction). In particular, when multiple light-shielding portions exist along the optical axis, the overlap of the openings of the light-shielding portions aligned in the optical axis direction forms the opening of the entire light-shielding portion, making it difficult to control the variation in the optical path area in the optical axis direction for each lens optical system.

[0006] The present invention aims to provide an optical element including a plurality of lenses, in which a plurality of light-blocking portions are arranged in the optical axis direction corresponding to each lens, and in which the optical element can easily control the optical path area of ​​each lens optical system. The present invention also aims to provide an optical sensor including the above optical element, and a biosensor including such an optical sensor. [Means for solving the problem]

[0007] In one aspect, the present invention, which solves the above-mentioned problems, provides an optical element comprising: a lens portion having a plurality of lenses each having an optical axis along a first direction; and a shading portion having a plurality of through holes provided at positions corresponding to the optical axes of each of the plurality of lenses, wherein the shading portion has a first shading portion that is sheet-shaped and relatively close to the lens portion; and a second shading portion that is sheet-shaped and relatively far from the lens portion; and a connecting portion that is located around the shading portion and has a wall-like body that extends in the first direction; and the connecting portion is formed integrally with the shading portion.

[0008] Because the light-shielding portion and the connecting portion are integrally formed, when the first light-shielding portion and the second light-shielding portion deform due to the relaxation of stress generated in the light-shielding portion during the formation of the light-shielding portion, these deformations are not independent of each other but deform integrally together with the connecting portion. As a result, misalignment between the positions of the through holes of the first light-shielding portion and the second light-shielding portion is unlikely to occur when viewed from the first direction. This improves controllability of the opening of the light-shielding portion, which is defined by the overlap between the through holes of the first light-shielding portion and the second light-shielding portion when viewed from the first direction, and as a result, improves controllability of the optical path area of ​​each lens optical system of the optical element.

[0009] In the optical member described above, the light-shielding portion and the connecting portion may be formed by plating. Forming the light-shielding portion and the connecting portion using a plating process makes it easy to integrally form them, but it is not easy to equalize the stresses generated in the first light-shielding portion and the second light-shielding portion during plating. Therefore, the first light-shielding portion and the second light-shielding portion are likely to exhibit different deformation behaviors due to stress relaxation. Therefore, when the light-shielding portion and the connecting portion are formed by plating, the light-shielding portion and the connecting portion are integrally formed and connected as in the optical member described above, which makes it easier to control the opening of the light-shielding portion compared to when they are not connected.

[0010] In the optical member described above, the first light-shielding portion and the second light-shielding portion may be connected to the side surface of the wall-like body at their respective peripheral edges. Because the first light-shielding portion and the second light-shielding portion are sheet-shaped, when they deform due to stress relaxation, they expand and contract in an in-plane direction along a plane normal to the first direction. Therefore, if the first light-shielding portion and the second light-shielding portion are not connected by a connecting portion, the displacement of their respective peripheral edges is likely to be maximized. Therefore, if the first light-shielding portion and the second light-shielding portion are configured to be connected to the side surface of the wall-like body at their respective peripheral edges, the first light-shielding portion and the second light-shielding portion are connected via the wall-like body at their respective maximum displacement positions, thereby enabling efficient control of the in-plane deformation of the first light-shielding portion and the second light-shielding portion.

[0011] In the optical member, it is preferable that the connecting portion is joined to the peripheral edge of the lens portion at an end surface of the wall-shaped body in the first direction.

[0012] Since the connecting body is joined to the member that constitutes the lens unit, deformation of the lens unit in an in-plane direction with the first direction as its normal can be made to align with deformation of the connecting body in an in-plane direction with the first direction as its normal. Because the connecting body deforms integrally with the light-shielding unit, deviation in deformation between the light-shielding unit and the lens unit is reduced, thereby achieving more stable and improved controllability of the optical path area of ​​the lens optical system.

[0013] In the optical member, the lens portion may be made of a resin-based material. When the lens portion is made of a resin-based material, the lens is easily deformed, but if the lens portion is connected to a connecting portion, the lens receives a deformation force from the connecting portion and deforms in accordance with the connecting portion, which tends to improve the controllability of the optical path area of ​​the lens optical system.

[0014] In the optical member described above, it is preferable that the connecting portion is provided so as to surround the periphery of the light-shielding portion when viewed from the first direction. When the connecting portion is provided so as to surround the light-shielding portion when viewed from the first direction, specifically when viewed from the first direction, the overall shape of the connecting portion is a frame shape, so that the connecting body and the light-shielding portion can be deformed integrally more stably.

[0015] In the optical element described above, the connecting portion preferably includes a plurality of the wall bodies arranged with gaps therebetween in a direction intersecting the first direction. In this case, even if abnormal stress accumulation occurs during the formation of the connecting portion and the degree of deformation of each wall body constituting the connecting portion increases as the stress is relaxed, the deformation can be absorbed by the gaps between adjacent wall bodies, thereby reducing the deformation amount of the connecting portion as a whole. This allows the connecting portion to control the deformation of the light-shielding portion due to stress relaxation, thereby stably ensuring the integrity of the deformation of the first light-shielding portion and the deformation of the second light-shielding portion.

[0016] In the optical member, the light-shielding portion may be blackened. By blackening the light-shielding portion, stray light is less likely to occur. In this case, it is preferable that at least the inner surface of the through hole of the light-shielding portion is blackened.

[0017] In another aspect, the present invention provides an optical sensor including the optical member described above and a light receiving element provided on the optical axis on the opposite side of the light blocking portion from the lens portion.

[0018] In another aspect, the present invention provides a biosensor including the optical sensor described above. [Effects of the Invention]

[0019] According to the present invention, for an optical element having a plurality of lenses and a configuration in which a plurality of light-blocking portions are arranged in the optical axis direction corresponding to each lens, it is possible to improve the controllability of the optical path area of ​​each lens optical system. Therefore, the optical element according to the present invention makes it possible to suppress variation in the optical path area of ​​each lens optical system. Furthermore, according to the present invention, there are also provided an optical sensor including the above optical element, and a biosensor including such an optical sensor. [Brief explanation of the drawings]

[0020] [Figure 1]1 is an explanatory diagram of an optical member according to a first embodiment of the present invention. [Figure 2] FIG. 2 is an explanatory view corresponding to the cross-sectional view taken along the line AA in FIG. [Figure 3] 5A and 5B are explanatory diagrams of an optical member according to a modified example of the first embodiment of the present invention. [Figure 4] 1 is an explanatory diagram of an optical sensor according to a first embodiment of the present invention; [Figure 5] 5A to 5C are diagrams illustrating an example of a method for evaluating a change in the relative position of a lens portion and a light-shielding portion of an optical member according to the first embodiment of the present invention. [Figure 6A] 6 is an explanatory diagram of FIG. 5 viewed from the Z1 side in the Z1-Z2 direction. [Figure 6B] FIG. 6B is a partially enlarged view of FIG. 6A. [Figure 7] 7 is an explanatory diagram showing a state in which the shielding portion of the optical member shown in FIG. 6 is deformed. FIG. [Figure 8] FIG. [Figure 9] 10 is a graph showing the measurement results of the amount of deviation of the optical member according to the example. [Figure 10] 10(a) is a cross-sectional view in the XZ plane illustrating an optical sensor equipped with an optical element according to a first example of the second embodiment of the present invention, and FIG. 10(b) is a view from the Z-axis direction illustrating the arrangement of each component in the optical element of FIG. 10(a). [Figure 11] FIG. 1A is a cross-sectional view in the XZ plane illustrating the function of an optical element according to a first example of the second embodiment of the present invention; FIG. 1B is a cross-sectional view in the XZ plane illustrating an optical element according to a first example of the second embodiment of the present invention, in which a virtual vertex is located outside the diameter of the through hole. [Figure 12] 10A is a cross-sectional view in the XZ plane illustrating the shape of an optical element according to a first example of the second embodiment of the present invention, and FIG. 10B is a diagram illustrating the angle of the side surface of a pyramidal body relative to the main axis. [Figure 13] 13(a) is a cross-sectional view in the XZ plane illustrating an optical sensor equipped with an optical element according to a second example of the second embodiment of the present invention, and FIG. 13(b) is a view from the Z-axis direction illustrating the arrangement of each component in the optical element of FIG. 13(a). [Figure 14]FIG. 10 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a third example of the second embodiment of the present invention. [Figure 15] FIG. 10 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a fourth example of the second embodiment of the present invention. [Figure 16] FIG. 10 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a fifth example of the second embodiment of the present invention. [Figure 17] FIG. 10 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a sixth example of the second embodiment of the present invention. [Figure 18] 10A and 10B are diagrams illustrating the structure of optical elements included in a collimator array according to a third embodiment of the present invention. [Figure 19] 10A to 10C are explanatory diagrams of a manufacturing method of a collimator array according to a third embodiment of the present invention. [Figure 20] FIG. 10 is an explanatory diagram of step 1 in the method for manufacturing a collimator array according to the third embodiment of the present invention. [Figure 21] FIG. 10 is an explanatory diagram of step 2 in the method for manufacturing a collimator array according to the third embodiment of the present invention. [Figure 22] 10 is an explanatory diagram (first half) of step 1 in the manufacturing method of a collimator array according to the fourth embodiment of the present invention. FIG. [Figure 23] 10 is an explanatory view (second half) of step 1 in the method for manufacturing a collimator array according to the fourth embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0021] (First embodiment) Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components will be assigned the same reference numerals, and the description of components that have already been described will be omitted as appropriate. Fig. 1 is an explanatory diagram of an optical member according to a first embodiment of the present invention. Fig. 2 is an explanatory diagram corresponding to the AA cross-sectional view of Fig. 1. Fig. 3 is an explanatory diagram of an optical member according to a modified example of the first embodiment of the present invention.

[0022] As shown in Figure 1, the optical element 100 of the first embodiment of the present invention comprises a lens section 10 having a plurality of lenses 11 each having an optical axis OA along a first direction (Z1-Z2 direction), and a light-shielding section 20 having a plurality of through holes (first through hole 21h, second through hole 22h) provided at positions corresponding to the optical axes OA of each of the plurality of lenses 11.

[0023] The shading portion 20 has a sheet-like first shading portion 21 that is located relatively closer to the lens portion 10, i.e., on the Z2 side in the Z1-Z2 direction in Figure 1, and a sheet-like second shading portion 22 that is located relatively farther from the lens portion 10, i.e., on the Z1 side in the Z1-Z2 direction in Figure 1.

[0024] The optical member 100 includes a connecting portion 30 having a plurality of wall-like bodies 31 positioned around each of the light-shielding portions 20 (first light-shielding portion 21, second light-shielding portion 22) and extending in a first direction (Z1-Z2 direction). The detailed shape of the connecting portion 30 will be described later. The connecting portion 30 connects to the light-shielding portions 20 (first light-shielding portion 21, second light-shielding portion 22) on the side surfaces of the wall-like bodies 31, and has the function of connecting the first light-shielding portion 21 and the second light-shielding portion 22 that are spaced apart in the first direction (Z1-Z2 direction). Specifically, the first light-shielding portion 21 is connected at its peripheral portion (both ends in the X1-X2 direction in FIG. 2) to a first connecting portion CP1 located on a side surface of the wall-shaped body 31 constituting the connecting portion 30, and the second light-shielding portion 22 is connected at its peripheral portion (both ends in the X1-X2 direction in FIG. 2) to a second connecting portion CP2 located on a side surface of the wall-shaped body 31 constituting the connecting portion 30. The space between the lens portion 10 and the second light-shielding portion 22 is filled with an optically adjusting material 40. The refractive index of the optically adjusting material 40 can be appropriately controlled to adjust the refraction angle of the lens 11.

[0025] In this embodiment, the light-shielding portion 20 (the first light-shielding portion 21 and the second light-shielding portion 22) and the connecting portion 30 are integrally formed by plating. In one specific example, the portion of the structure including the light-shielding portion 20 (the first light-shielding portion 21 and the second light-shielding portion 22) and the connecting portion 30 above the parting surface SP (the Z1 side in the Z1-Z2 direction) indicated by the two-dot chain line in FIG. 1 is formed by a plating process that is different from the portion below the parting surface SP (the Z2 side in the Z1-Z2 direction). For convenience, the plating process for forming the portion above the parting surface SP (the Z1 side in the Z1-Z2 direction) is referred to as the first plating process, and the plating process for forming the portion below the parting surface SP (the Z2 side in the Z1-Z2 direction) is referred to as the second plating process. By the second plating process, the portion (lower portion) of the connecting portion 30 that will be the lower side (the Z2 side in the Z1-Z2 direction) (the lower portion) and the second light-shielding portion 22 are integrally formed. This results in a structure in which the second light-shielding portion 22 is connected at its periphery to the second connection portion CP2 of the connecting portion 30. Then, by the first plating process, a portion (upper portion) that will be the upper side (Z1 side in the Z1-Z2 direction) of the connecting portion 30 is formed on the surface (the surface on the Z1-Z2 direction Z1 side) of a portion (lower portion) that constitutes a part of the connecting portion 30 in this structure, and the first light-shielding portion 21 is formed as an integral part with this upper portion. This results in a structure in which the first light-shielding portion 21 is connected at its periphery to the first connection portion CP1 of the connecting portion 30. Because the lower portion formed by the second plating process and the upper portion formed by the first plating process are firmly joined, the connecting portion 30 becomes substantially an integral part. In this way, a structure in which the first light-shielding portion 21 and the second light-shielding portion 22 are connected via the connecting portion 30 is obtained.

[0026] The light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) and the connecting portion 30 may be formed by electroplating or electroless plating. From the viewpoint of increasing productivity, it may be preferable to form them by electroplating. Plated members, particularly those formed by electroplating, are prone to accumulate stress during plating formation. This stress is alleviated by deformation of the plated member when the plated member is heated. In other words, when a plated member is heated, the stress during formation is alleviated by deformation of the member. The light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) and the connecting portion 30, which are integrally formed by plating, are also subjected to heating, particularly heating to 100°C or higher during the manufacturing process, which alleviates stress.

[0027] The manufacturing environments (plating conditions such as plating solution composition and current density) of the first light-shielding portion 21 and the second light-shielding portion 22 may not be exactly the same, and it is more common for the manufacturing environments to be different, as in the case of the first and second plating steps described above. For this reason, the degree of stress accumulated during plating differs between the first light-shielding portion 21 and the second light-shielding portion 22. Therefore, the tendency for shape deformation when stress is relieved also generally differs between the two portions.

[0028] As in a comparative example described later, if the deformation of the first light-shielding portion 21 and the second light-shielding portion 22 is not controlled and they are capable of being deformed independently of each other, in the lens optical system 15 (located in the area surrounded by the two-dot chain line in FIG. 2 ) constituted by each lens 11 and the first through-hole 21 h and the second through-hole 22 h arranged along the optical axis OA (first direction (Z1-Z2 direction)) of the lens 11, the independent deformations of the first light-shielding portion 21 and the second light-shielding portion 22 will cause the first through-hole 21 h and the second through-hole 22 h to be shifted independently of each other with respect to the optical axis OA. Therefore, it is impossible to control the position or size of the opening of the light-shielding portion 20, which is defined by the overlap of the first through-hole 21 h and the second through-hole 22 h when viewed from the first direction (Z1-Z2 direction).

[0029] In contrast, in the present embodiment, when the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) and the connecting portion 30 are integrally formed, the deformations of the first light-shielding portion 21 and the second light-shielding portion 22 due to stress relaxation are not independent of each other, but are integrally deformed via the connecting portion 30. As a result, in each lens optical system 15, the deviations of the first through-hole 21h and the second through-hole 22h with respect to the optical axis OA tend to exhibit similar trends. Therefore, it is possible to control the position and size of the opening of the light-shielding portion 20 in each lens optical system 15.

[0030] In the optical element 100 according to this embodiment, the end surface 30S in the first direction (the surface on the Z2 side in the Z1-Z2 direction) of the wall-like body 31 of the connecting portion 30 is bonded to a portion of the lens portion 10 where no lens 11 is provided, specifically, to the peripheral edge portion of the lens portion 10. By bonding the connecting portion 30 to the member that constitutes the lens portion 10, it is possible to align deformation of the lens portion 10 in an in-plane direction (XY in-plane direction) with the first direction (Z1-Z2 direction) as the normal line with deformation of the connecting portion 30 in an in-plane direction (XY in-plane direction) with the first direction (Z1-Z2 direction) as the normal line. Because the connecting portion 30 deforms integrally with the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22), it is easy to align the deformation behavior of the lens portion 10 with the deformation behavior of the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22), thereby reducing the deviation in deformation between the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) and the lens portion 10. Therefore, in the optical element 100 according to this embodiment, it is easy to improve the controllability of the optical path area in each lens optical system 15.

[0031] Here, when the lens portion 10 is made of a resin-based material, the lens 11 is easily deformed because the Young's modulus of the resin-based material is relatively low. However, if the lens portion 10 is connected to the connecting portion 30 in this manner, the lens portion 10 receives a deformation force from the connecting portion 30 and deforms in accordance with the connecting portion 30. This makes it possible to more stably improve the controllability of the optical path area in each lens optical system 15.

[0032] The connecting portion 30 shown in FIG. 1 is provided so as to surround the periphery of the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) when viewed from the first direction (Z1-Z2 direction). In other words, the overall shape of the connecting portion 30 when viewed from the first direction (Z1-Z2 direction) is a frame shape FS (shown by a two-dot chain line in FIG. 1). By configuring the connecting portion 30 in this manner, the connecting portion 30 can efficiently absorb deformation of the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) in the XY plane and can efficiently transmit deformation of the connecting portion 30 to the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) in the XY plane. This makes it easy to align the deformation behavior of the first light-shielding portion 21 and the deformation behavior of the second light-shielding portion 22. Therefore, the optical element 100 according to this embodiment facilitates improving the controllability of the optical path area of ​​each lens optical system 15.

[0033] 1 has a structure in which a plurality of wall-like bodies 31 are arranged with gaps GP in a direction intersecting the first direction (Z1-Z2 direction). Each wall-like body 31 is connected at its side surface to the first light-shielding part 21 and the second light-shielding part 22, respectively. That is, each wall-like body 31 has a first connection part CP1 and a second connection part CP2 (see FIG. 2).

[0034] If an abnormal amount of stress accumulates in the connecting portion 30 during plating formation, the connecting portion 30 may deform excessively during stress relaxation, making it difficult to control the deformation behavior of the light-shielding portion 20. If the connecting portion 30 is composed of multiple wall bodies 31, the gap GP between two adjacent wall bodies 31 can absorb the deformation of each wall body 31. Therefore, even if abnormal stress accumulation occurs in the connecting portion 30, the amount of deformation of the connecting portion 30 as a whole can be reduced. This allows the connecting portion 30 to control the deformation of the light-shielding portion 20 due to stress relaxation, thereby stably ensuring the integrity of the deformation of the first light-shielding portion 21 and the deformation of the second light-shielding portion 22.

[0035] As in the optical member 101 according to the modified example shown in Fig. 3, the light-shielding portion 20 may be provided with a blackening treatment portion BT that has been subjected to blackening treatment. By providing the light-shielding portion 20 with a blackening treatment portion BT, stray light is less likely to occur. The blackening treatment portion BT is preferably provided at least on the inner surfaces of the through holes (first through holes 21h, second through holes 22h), and it is more preferable that the blackening treatment portion BT is also provided on the main surface of the light-shielding portion 20 (a surface normal to the first direction (Z1-Z2 direction)).

[0036] FIG. 4 is an explanatory diagram of an optical sensor 1000 including an optical element 100 according to this embodiment. The optical element 100 is positioned upside down compared to the position shown in FIG. 2, with multiple light-receiving elements 50 arranged inside a housing 51 on the side where the second light-shielding portion 22 is located. The multiple light-receiving elements 50 are arranged inside the housing 51 so that their central axes overlap the optical axes OA of the individual lenses 11. When a measurement object is positioned on the side where the lens portion 10 of the optical sensor 1000 is provided, reflected light from the measurement object is incident on the individual lens optical systems 15 of the optical element 100, and the appropriately adjusted light reaches the light-receiving elements 50, thereby performing image recognition of the measurement object. If the measurement object is, for example, a finger, image recognition of the fingerprint is performed, and the optical sensor 1000 can function as a biometric sensor.

[0037] Below, we will explain an example of a method for evaluating changes in the relative positions of the lens portion 10 and the light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22) in the process of manufacturing an optical element 100 having a light-shielding portion 20 (first light-shielding portion 21, second light-shielding portion 22).

[0038] FIG. 5 is a diagram illustrating an example of a method for evaluating changes in the relative positions of the lens portion and the light-shielding portion of an optical element. FIG. 6A is an explanatory diagram of FIG. 5 as viewed from the Z1 side in the Z1-Z2 direction. FIG. 6B is a partially enlarged view of FIG. 6A. Specifically, a portion of the upper left of FIG. 6A is enlarged. FIG. 7 is an explanatory diagram illustrating a state in which the light-shielding portion of the optical element shown in FIG. 6 is deformed. The structure 100p shown in FIG. 5 illustrates the structure of the optical element 100 during the manufacturing process, in which the lens portion 10, the first light-shielding portion 21, and the second light-shielding portion 22 are stacked. For ease of explanation, the connecting portion 30 formed integrally with the first light-shielding portion 21 and the second light-shielding portion 22 is not shown.

[0039] The sheet-like first light-shielding portion 21 and second light-shielding portion 22 included in the structure 100p each have cutouts at their four corners. These cutouts are located outside the detection range of the optical sensor 1000 including the optical member 100, and are not used for detection during use.

[0040] When viewed from the Z1-Z2 direction, first cutout portions 21ra, 21rb, 21rc, and 21rd are provided at four corners of the first light-shielding portion 21. When viewed from the Z1-Z2 direction, each of the first cutout portions 21ra, 21rb, 21rc, and 21rd has a quadrangle shape including one first through-hole 21h.

[0041] When viewed from the Z1-Z2 direction, second cutouts 22ra, 22rb, 22rc, and 22rd are provided at the four corners of the second light-shielding portion 22. When viewed from the Z1-Z2 direction, the second cutouts 22ra, 22rb, 22rc, and 22rd each have a rectangular shape including two first through-holes 21h. The long sides of the second cutouts 22ra and 22rc extend in the Y1-Y2 direction, and the long sides of the second cutouts 22rb and 22rd extend in the X1-X2 direction.

[0042] 6A and 6B, one lens 11 (exposed lenses 11a, 11b, 11c, 11d) is exposed at each of the four corners of the lens group included in the lens unit 10. Furthermore, since the shapes of the first cutout portions 21ra, 21rb, 21rc, 21rd and the second cutout portions 22ra, 22rb, 22rc, 22rd are different from each other, one first through-hole 21h (exposed first through-holes 21a, 21b, 21c, 21d) corresponding to the lenses 11 arranged next to the exposed lenses 11a, 11b, 11c, 11d in the structure 100p is exposed at each of the four corners when viewed from the Z1-Z2 direction. Corresponding to the shapes of the second cutouts 22ra, 22rb, 22rc, and 22rd, the combination of exposed lens 11a and exposed first through hole 21a and the combination of exposed lens 11c and exposed first through hole 21c are aligned along the Y1-Y2 direction, and the combination of exposed lens 11b and exposed first through hole 21b and the combination of exposed lens 11d and exposed first through hole 21d are aligned along the X1-X2 direction.

[0043] Here, when viewed from the Z1-Z2 direction, the second through holes 22h located at a position obtained by rotating the exposed first through holes 21a, 21b, 21c, and 21d 90 degrees counterclockwise around the exposed lenses 11a, 11b, 11c, and 11d are defined as the target second through holes 22a, 22b, 22c, and 22d, and the rectangle obtained by connecting the centers of the four exposed lenses 11a, 11b, 11c, and 11d is defined as the lens rectangle Qd11, the rectangle obtained by connecting the centers of the four exposed first through holes 21a, 21b, 21c, and 21d is defined as the first rectangle Qd21, and the rectangle obtained by connecting the centers of the four target second through holes 22a, 22b, 22c, and 22d is defined as the second rectangle Qd22. In FIG. 6A, the lens rectangle Qd11 is shown by a dashed line, the first rectangle Qd21 is shown by a dashed line, and the second rectangle Qd22 is shown by a dotted line.

[0044] During the manufacturing process, if the lens portion 10 of the structure 100p deforms, the lens rectangle Qd11 deforms, if the first light-shielding portion 21 of the structure 100p deforms, the first rectangle Qd21 deforms, and if the second light-shielding portion 22 of the structure 100p deforms, the second rectangle Qd22 deforms. Therefore, as will be described next, by measuring the shapes of these three rectangles during the manufacturing process, it can be determined whether the structure 100p is a non-defective product.

[0045] In the structure 100p shown in FIG. 7 as a specific example, the first light-shielding portion 21 extends in the X1-X2 direction and the second light-shielding portion 22 extends in the Y1-Y2 direction due to stress relaxation that occurred during the manufacturing process. As a result, the first exposed through-hole 21a moves toward the X1 side in the X1-X2 direction from its position (shown by the dashed circle) before stress relaxation (FIG. 6), and the second through-hole of interest 22a moves toward the Y1 side in the Y1-Y2 direction from its position (shown by the dashed circle) before stress relaxation (FIG. 6). As a result, the distance between the first exposed through-hole 21a and the second through-hole of interest 22a and the exposed lens 11a increases. Although the directions of the relative movements are different, a similar tendency (increased distance) occurs between the first exposed through-hole 21c and the second through-hole of interest 22c and the exposed lens 11a.

[0046] Meanwhile, the exposed first through hole 21b moves toward the X2 side in the X1-X2 direction from its position (indicated by the dashed circle) before stress relaxation (FIG. 6), and the second through hole of interest 22b moves toward the Y1 side in the Y1-Y2 direction from its position (indicated by the dashed circle) before stress relaxation (FIG. 6). As a result, the distances between the exposed first through hole 21b and the second through hole of interest 22b and the exposed lens 11b become shorter. Although the directions of the relative movements are different, a similar tendency (a decrease in the distance) occurs between the exposed first through hole 21d and the second through hole of interest 22d and the exposed lens 11a.

[0047] In this way, when the first light-shielding portion 21 and the second light-shielding portion 22 are deformed, the relative positions of the lens 11 of the lens unit 10, the first through-hole 21h of the first light-shielding portion 21, and the second through-hole 22h of the second light-shielding portion 22 change. This means that the optical path area of ​​each lens optical system 15 of the structure 100p changes. Since it is important to appropriately ensure the optical path area for each lens optical system 15 in order to maintain the quality of the optical member 100 formed from the structure 100p, it is preferable to be able to appropriately evaluate the optical path area even during the manufacturing process (in the state of the structure 100p). However, it is not realistic to measure the optical path area of ​​the many lens optical systems 15 included in the structure 100p during manufacturing.

[0048] Therefore, during the manufacturing process, the degree of deformation of the lens rectangle Qd11, first light-shielding portion 21, and second light-shielding portion 22 is evaluated. Comparing Figure 6 with Figure 7, the shape of the lens rectangle Qd11 does not change, but the shapes of the first rectangle Qd21 and second rectangle Qd22 have changed. Therefore, from the change in shape of these rectangles, it can be seen that the lens rectangle Qd11 has not deformed, but the first light-shielding portion 21 and second light-shielding portion 22 have deformed.

[0049] Furthermore, quantitative information about the degree of deformation of the component corresponding to the rectangle can be obtained from the amount of change in the shape of each rectangle, and therefore the amount of deviation in the relative positions of the lens 11, the first through hole 21h, and the second through hole 22h can be determined for all lens optical systems 15 possessed by the optical element 100.

[0050] If the determined relative positional deviation amounts are within a predetermined range, the evaluated structure 100p can be determined as a non-defective product, and if any of the determined relative positional deviation amounts exceeds the predetermined range, the evaluated structure 100p can be determined as a defective product. Alternatively, the optical path area of ​​each lens optical system 15 can be determined from the determined relative positional deviation amounts of the first through hole 21h and the second through hole 22h, and if all of these optical path area areas are within a predetermined range, the evaluated structure 100p can be determined as a non-defective product, and if any of the optical path area areas are outside the predetermined range, the evaluated structure 100p can be determined as a defective product.

[0051] The above-described embodiments have been described to facilitate understanding of the present invention, and are not intended to limit the present invention. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0052] In the optical members 100 and 101, the multiple lens optical systems 15 are arranged in the X1-X2 and Y1-Y2 directions in the XY plane, but this is not limiting. For example, the multiple lens optical systems 15 may be arranged in a honeycomb pattern in the XY plane. Furthermore, in the optical members 100 and 101, the multiple lenses 11 of the lens unit 10 are arranged with intervals between them in the X1-X2 and Y1-Y2 directions, but the multiple lenses 11 may be arranged without any intervals. The same applies to the through holes of the light-shielding unit 20. For example, the first light-shielding unit 21 may have multiple first through holes 21h arranged consecutively in the X1-X2 direction, and the second light-shielding unit 22 may have multiple second through holes 22h arranged consecutively in the Y1-Y2 direction.

[0053] The lens portion 10 and the optical adjustment material 40 may each be composed of a laminate of multiple members. By appropriately controlling the refractive indexes of these members, it may be possible to control the optical properties of each lens optical system 15 in detail. [Example]

[0054] The present invention will be described in more detail below with reference to examples. The optical member according to the example has the configuration of the optical member 100 according to the first embodiment. The optical member according to the comparative example (comparative optical member) has the configuration of the optical member 100 according to the first embodiment, excluding the connecting portion 30.

[0055] FIG. 8 is an explanatory diagram of an example. Optical element 100 and the comparative optical element share a common structure except for the connecting portion 30. Therefore, the regions other than the peripheral portion of the shielding member have the structure shown in FIG. 8. Specifically, the structure includes a lens portion 10 having a plurality of lenses 11 each having an optical axis OA along a first direction (Z1-Z2 direction), a sheet-like first light-shielding portion 21 relatively proximal to the lens portion 10 (located on the Z1 side in the Z1-Z2 direction), and a sheet-like second light-shielding portion 22 relatively distal from the lens portion 10 (located on the Z2 side in the Z1-Z2 direction). Due to manufacturing reasons, in both optical element 100 and the comparative optical element, there is a misalignment between the central axis (first central axis HA1) of the first through-hole 21h of the first light-shielding portion 21 and the optical axis OA, and there is a misalignment between the central axis (second central axis HA2) of the second through-hole 22h of the second light-shielding portion 22 and the optical axis OA.

[0056] The positional deviation between the first center axis HA1 and the optical axis OA is not uniform among the multiple lens optical systems 15 arranged on the XY plane, but varies depending on the degree of deformation of the first light-shielding unit 21 relative to the lens unit 10. The positional deviation between the second center axis HA2 and the optical axis OA is also not uniform among the multiple lens optical systems 15 arranged on the XY plane, but varies depending on the degree of deformation of the second light-shielding unit 22 relative to the lens unit 10.

[0057] Among the multiple lens optical systems 15 arranged along the X1-X2 direction in the optical element 100, the amount of misalignment between the first central axis HA1 and the optical axis OA in the X1-X2 direction (first misalignment SD1) and the amount of misalignment between the second central axis HA2 and the optical axis OA in the X1-X2 direction (second misalignment SD2) were measured for the left side (X2 side in the X1-X2 direction), center, and right side (X1 side in the X1-X2 direction) (Example). Similarly, the first misalignment SD1 and the second misalignment SD2 were measured for a comparative optical element (Comparative Example). The results are shown in Table 1. In Table 1, misalignment to the left (X2 side in the X1-X2 direction) is indicated by a negative value (unit: μm), and misalignment to the right (X1 side in the X1-X2 direction) is indicated by a positive value (unit: μm).

[0058] [Table 1]

[0059] As shown in Table 1, in the example, in the left portion (X2 side in the X1-X2 direction) of the optical member 100, the central axis of the first through hole 21h of the first light-shielding portion 21 was shifted by 3.2 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11. On the other hand, the central axis of the second through hole 22h of the second light-shielding portion 22 was shifted by 2.3 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11.

[0060] In the example, in the portion near the center of the optical member 100, the central axis of the first through hole 21h of the first light-shielding portion 21 was shifted 0.2 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11. On the other hand, the central axis of the second through hole 22h of the second light-shielding portion 22 was shifted 0.3 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11.

[0061] In the example, in the right part (X1 side in the X1-X2 direction) of the optical member 100, the central axis of the first through hole 21h of the first light-shielding portion 21 was shifted by 3.8 μm to the right (X1 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11. On the other hand, the central axis of the second through hole 22h of the second light-shielding portion 22 was shifted by 5.0 μm to the right (X1 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11.

[0062] In contrast, in the comparative example, in the left side (X2 side in the X1-X2 direction) of the comparative optical member, the central axis of the first through hole 21h of the first light-shielding portion 21 was shifted by 2.6 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11. Meanwhile, the central axis of the second through hole 22h of the second light-shielding portion 22 was shifted by 6.0 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11.

[0063] In the comparative example, in the portion near the center of the comparative optical member, the central axis of the first through hole 21h of the first light-shielding portion 21 was shifted 8.4 μm to the right (X1 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11. On the other hand, the central axis of the second through hole 22h of the second light-shielding portion 22 was shifted 8.6 μm to the right (X1 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11.

[0064] In the comparative example, in the right part (X1 side in the X1-X2 direction) of the comparative optical member, the central axis of the first through hole 21h of the first light-shielding portion 21 was shifted by 0.5 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11. On the other hand, the central axis of the second through hole 22h of the second light-shielding portion 22 was shifted by 2.8 μm to the left (X2 side in the X1-X2 direction) with respect to the optical axis OA of the lens 11.

[0065] In the optical element 100 according to the example, there was no clear tendency for the magnitude of the first positional deviation SD1 and the second positional deviation SD2. In contrast, a regularity was observed in the relationship between the measurement position and both the first positional deviation SD1 and the second positional deviation SD2. Specifically, for both the first through hole 21h and the second through hole 22h, the left side (the X2 side in the X1-X2 direction) tended to be shifted to the left (the X2 side in the X1-X2 direction) based on the optical axis OA of the lens 11, and the right side (the X1 side in the X1-X2 direction) tended to be shifted to the right (the X1 side in the X1-X2 direction) based on the optical axis OA of the lens 11, with the amount of deviation being relatively small in the central portion. That is, in the X1-X2 direction, there was a tendency for the deviation to be small in the central portion and for the deviation amount to increase toward the end. This means that the arrangement pitch of the through holes (first through holes 21h, second through holes 22h) in the shading portion 20 (first shading portion 21, second shading portion 22) is larger than the arrangement pitch of the lenses 11 in the lens portion 10.

[0066] To confirm this tendency, the first positional deviation SD1 and the second positional deviation SD2 were measured for multiple lens optical systems 15 aligned in the X1-X2 direction. The results are shown in Fig. 9. In the graph shown in Fig. 9, the horizontal axis represents the coordinates (unit: mm) of the optical axis OA of the lens 11 of each lens optical system 15, with the left end (the end on the X2 side in the X1-X2 direction) of the optical member 100 as the reference point. The vertical axis, which represents the deviation amount of the first light-shielding portion 21 (first positional deviation SD1) and the deviation amount of the second light-shielding portion 22 (second positional deviation SD2), indicates a negative value (unit: µm) for deviation to the left (the X2 side in the X1-X2 direction) and a positive value (unit: µm) for deviation to the right (the X1 side in the X1-X2 direction). As shown in Figure 9, it was confirmed that for both the first light-shielding portion 21 and the second light-shielding portion 22, there was a positional shift to the left on the left side of the optical element 100 (the X2 side in the X1-X2 direction), and the positional shift shifted more to the right as one moved toward the right side of the optical element 100 (the X1 side in the X1-X2 direction).

[0067] 9 are approximate straight lines, with the upper dashed line being an approximate line based on the measurement results of the first light-shielding portion 21 and the lower dashed line being an approximate line based on the measurement results of the second light-shielding portion 22. From these approximate lines, it can be seen that, with the first light-shielding portion 21, the lens optical system 15 where the first positional deviation SD1 is approximately zero is located slightly to the left of the center of the optical element 100 in the X1-X2 direction (the X2 side in the X1-X2 direction), and that with the second light-shielding portion 22, the lens optical system 15 where the second positional deviation SD2 is approximately zero is located approximately at the center of the optical element 100 in the X1-X2 direction.

[0068] When the tendency is clear as described above, by slightly reducing the arrangement pitch of the through holes in the design values ​​of the first shading section 21 and the second shading section 22, it is possible to reduce the difference in the amount of positional deviation between the left and right sides and manufacture an optical element 100 having a lens optical system 15 with little deviation in the opening of the shading section 20.

[0069] In contrast, in the comparative optical member, the positional deviation is to the left on both the first light-shielding portion 21 and the second light-shielding portion 22, to the right in the center, and to the left on the right. When the tendency of the direction of deviation is inconsistent, it is difficult to correct the deviation by modifying the design values. Furthermore, as a basic tendency, the absolute value of the second positional deviation SD2 is larger than the absolute value of the first positional deviation SD1. This indicates that the deformation behavior of the first light-shielding portion 21 and the second light-shielding portion 22 is independent, and the opening of the light-shielding portion 20 tends to become smaller.

[0070] (Second embodiment) Fig. 10(a) is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a first example of the second embodiment of the present invention, and Fig. 10(b) is a view from the Z-axis direction illustrating the arrangement of each component in the optical member of Fig. 10(a).

[0071] As shown in FIG. 10 , an optical sensor 2000 according to a first example of the second embodiment of the present invention includes an optical member 500 and a light receiving device 200. The light receiving device 200 includes a light receiving element 210 provided on a substrate 220. The light receiving element 210 may include a single light receiving unit or multiple light receiving units. A specific example of a configuration including multiple light receiving units is a configuration in which multiple light receiving units are arranged in a two-dimensional array on the Z1 side of the light receiving element 210 in the Z1-Z2 direction. In the following description, a specific example is taken of a case in which the entire surface of the Z1 side of the light receiving element 210 in the Z1-Z2 direction is a light receiving unit and the amount of received light can be measured in an analog manner.

[0072] Optical member 500 is disposed corresponding to the light receiving portion of light receiving element 210 of light receiving device 200, i.e., facing the Z1 side in the Z1-Z2 direction of light receiving element 210. Optical member 500 includes condenser lens 410, aperture 420 disposed opposite to the output side (Z2 side in the Z1-Z2 direction) of condenser lens 410 in the main axis direction, which is the direction along optical axis OA, of condenser lens 410, and having through-hole 422 along the main axis direction (Z1-Z2 direction), and translucent cone-shaped body 430 disposed between condenser lens 410 and aperture 420.

[0073] In this example, the condenser lens 410 is made of a transparent member having a convex surface 411 that protrudes toward the Z1 side in the Z1-Z2 direction, but is not limited to this. The condenser lens 410 may perform the condensing function by the surface shape or by a change in internal concentration, as long as it can achieve the condensing function of converging light incident along the principal axis direction toward a focal point.

[0074] Aperture 420 is formed by providing through-hole 422, having a through-axis along the Z1-Z2 direction, in light-blocking member 421 that extends in the in-plane direction of the XY plane and has a thickness (length in the Z1-Z2 direction). In aperture 420, the through-axis of through-hole 422 coincides with optical axis OA, and through-thickness LH is equal to thickness LT of aperture 420 and is equal to or greater than through-hole diameter DH. In this case, emission length LE, which is the relative distance in the main axis direction (Z1-Z2 direction) between the opening on the emission side (Z2 side in the Z1-Z2 direction) of through-hole 422 and focal point F, can easily be equal to or greater than through-hole diameter DH.

[0075] In this specification, a cone-shaped body is a general term for a component having an ideal shape of a cone or a frustum, and the end of the cone that corresponds to the cone-shaped body and is closest to the apex is defined as the tip. In this embodiment, the cone-shaped body 430 has a frustum-shaped outer shape with its tip 431 facing the output side (Z2 side in the Z1-Z2 direction) in the main axis direction and with a base 432 on the tip 431 side. The central axis of the cone-shaped body 430 coincides with the optical axis OA, and the base 432 of the cone-shaped body 430 is formed by a plane having a normal along the Z1-Z2 direction.

[0076] When the optical element 500 is viewed in the main axis direction (Z1-Z2 direction), a virtual vertex VS corresponding to the vertex of the cone corresponding to the cone-shaped body 430 is located within the diameter of the through-hole 422 (see FIG. 10(b)). This makes it possible to guide light that should reach the light receiving element 210 into the inside of the through-hole 422.

[0077] When light having an incident optical axis LA aligned with the optical axis OA is incident on the condenser lens 410, the light traveling toward the Z2 side in the Z1-Z2 direction is bent by the convex surface 411 and converged between an X1-side optical path L1, which is an optical path at the end on the X1 side in the X1-X2 direction, and an X2-side optical path L2, which is an optical path at the end on the X2 side in the X1-X2 direction. The light passing through the X1-side optical path L1 and the light passing through the X2-side optical path L2 intersect at a focal point F. In this embodiment, the focal point F is located on the bottom 432 of the pyramidal body 430 formed by a frustum. The light that passes through the focal point F is diffused and reaches the light receiving element 210.

[0078] FIG. 11(a) is a cross-sectional view in the XZ plane illustrating the function of an optical element according to a first example of the second embodiment of the present invention. FIG. 11(b) is a cross-sectional view in the XZ plane illustrating an optical element according to a first example of the second embodiment of the present invention, in which the virtual vertex is located outside the diameter of the through hole. In FIG. 11(a), the incident optical axis LA of light incident on the condenser lens 410 does not coincide with the optical axis OA. Specifically, the incident optical axis LA is inclined toward the X1 side in the X1-X2 direction as viewed from the front side of the page (the Y1 side in the Y1-Y2 direction). Therefore, the X1-side optical path L1 in FIG. 11 has a larger inclination angle with respect to the Z1-Z2 direction than the X1-side optical path L1 in FIG. 10, and the X2-side optical path L2 in FIG. 11 has a smaller inclination angle with respect to the Z1-Z2 direction than the X2-side optical path L2 in FIG. 11. Therefore, in FIG. 11, the convergence position (convergence point Pc) of the incident light is shifted toward the X2 side in the X1-X2 direction from the focal point F of the incident light in FIG.

[0079] As a result, light passing through the X1-side optical path L1 is reflected at a first reflecting point R1 on the side surface 434 of the cone-shaped body 430, and light passing through the X2-side optical path L2 is reflected at a second reflecting point R2 on the side surface 434 of the cone-shaped body 430. Both the light passing through the first reflected optical path L1R, which is the optical path after reflection at the first reflecting point R1, and the light passing through the second reflected optical path L2R, which is the optical path after reflection at the second reflecting point R2, have a large inclination angle with respect to the optical axis OA and travel toward the X2 side in the X1-X2 direction. The light passing through the first reflected optical path L1R cannot enter the through-hole 422 and reaches the incident side of the light-shielding member 421 (the Z1 side in the Z1-Z2 direction). The light passing through the second reflected optical path L2R reaches the inner wall of the through-hole 422. 11, the incident light travels within the range between the first reflected light path L1R and the second reflected light path L2R, and therefore the incident light does not reach the light receiving element 210 at all.

[0080] As shown in FIG. 10(b), when the optical element 500 is viewed in the main axis direction (Z1-Z2 direction), the virtual vertex VS is located within the diameter of the through-hole 422, and the through-hole thickness LH is equal to or greater than the through-hole diameter DH. This reliably prevents light reflected by the side surface 434 of the cone-shaped body 430 from reaching the light receiving element 210. FIG. 11(b) shows an optical element 500X in which the virtual vertex VS is located outside the diameter of the through-hole 422, specifically, in which the through-axis AA of the through-hole 422 in the aperture 420 is significantly offset from the optical axis OA toward the X1 side in the X1-X2 direction. In this case, there is a risk that light reflected by the side surface 434 of the cone-shaped body 430 may reach the light receiving element 210. In the optical sensor 2001 equipped with the optical element 500X shown in Figure 11(b), light passing through an optical path in the range between the second reflected optical path L2R and the optical path L1O located on the X1 side in the X1-X2 direction than the second reflected optical path L2R reaches the light receiving element 210.

[0081] Furthermore, when the through-hole thickness LH is less than the through-hole diameter DH, the light passing through the second reflected light path L2R does not reach the inner wall of the through-hole 422 of the aperture 420 and is therefore not blocked, and can travel between the aperture 420 and the light receiving device 200. In the optical sensor 2001 of FIG. 11(b), the light passing through the optical path in the range between the optical paths L1O and L2O is diffused outside the range of the optical member 500X. There is a risk that the diffused light will be reflected by other members positioned around the optical member 500X and reach the light receiving element 210. Furthermore, as will be described later, in an optical unit 300 having a structure in which optical members 500 are integrated, there is a risk that diffused light from other optical members 500 positioned nearby will be incident on the light receiving element 210.

[0082] From the viewpoint of more reliably avoiding the influence of diffused light on the light receiving device 200 side (Z2 side in the Z1-Z2 direction) of the aperture 420, the distance (gap LG) between the exit side (Z2 side in the Z1-Z2 direction) opening of the through-hole 422 and the entrance side (Z1 side in the Z1-Z2 direction) end of the light receiving element 210 is preferably equal to or less than the through-hole thickness LH, and a non-reflective member is more preferably disposed around the XY plane side of the light receiving element 210. The exit side (Z2 side in the Z1-Z2 direction) of the aperture 420 may abut against the substrate 220 of the light receiving device 200. Alternatively, the light receiving element 210 may abut against the exit side (Z2 side in the Z1-Z2 direction) of the aperture 420, and the aperture 420 may perform the function of the substrate 220 of the light receiving device 200.

[0083] Fig. 12(a) is a cross-sectional view in the XZ plane illustrating the shape of an optical member according to a first example of the second embodiment of the present invention. Fig. 12(b) is a diagram illustrating the angle of the side surface of the pyramidal body relative to the main axis direction. In Fig. 12(a), hatching of the pyramidal body 430 has been omitted for ease of viewing.

[0084] The virtual vertex VS of the cone-shaped body 430 is located closer to the output side in the direction of the optical axis OA (the Z2 side in the Z1-Z2 direction) than the focal point F of the condenser lens 410. In this case, there is a low possibility that light having an incident optical axis along the direction of the main axis will reach the side surface 434 of the cone-shaped body 430 before reaching the focal point F and deviate from the optical axis OA leading to the light receiving element 210, making it easier to increase the amount of light reaching the light receiving element 210.

[0085] The cone-shaped body 430 has a truncated cone shape with a bottom 432 on its tip 431 side (the Z2 side in the Z1-Z2 direction), and its side surface 434 is formed as a smooth surface. In other words, the cone corresponding to the cone-shaped body 430 is a cone. This prevents light incident on the cone-shaped body 430 from being reflected by the side surface 434 in an unexpected direction.

[0086] Light emitted from the cone-shaped body 430 passes through the bottom 432, and is therefore less likely to be scattered. The bottom 432 on the tip 431 side (Z2 side in the Z1-Z2 direction) of the cone-shaped body 430 has a flat surface. Specifically, the normal to the flat surface of the bottom 432 is along the main axis direction (Z1-Z2 direction). This reduces loss of light emitted from the cone-shaped body 430.

[0087] The equivalent circle diameter DT of the bottom 432 on the tip 431 side (Z2 side in the Z1-Z2 direction) of the cone-shaped body 430 is the diameter of a circle having an area equal to the area of ​​the shape obtained by projecting the bottom 432 onto a plane (XY plane) perpendicular to the main axis direction (Z1-Z2 direction). Other equivalent circle diameters also refer to the diameter of a circle having an area equal to the area of ​​the shape obtained by projecting the target shape onto a plane (XY plane) perpendicular to the main axis direction (Z1-Z2 direction). The through-hole diameter DH is equal to or greater than the equivalent circle diameter DT of the bottom 432 and equal to or less than the aperture diameter DL of the condenser lens 410. This allows light incident on the condenser lens 410 to be appropriately guided to the through-hole 422.

[0088] The ratio (LP / DB) of the height LP of the cone (which is a circular cone) corresponding to the conical body 430 to the diameter DB in terms of a circle of the bottom surface of the cone is smaller than the ratio (LF / DL) of the focal length LF of the condenser lens 410 to the aperture DL of the condenser lens 410. As shown in FIG. 12, in the optical member 500, since DL = DB, LP < LF. By satisfying such a relationship, the possibility that the light incident on the condenser lens 410 is reflected by the side surface 434 of the conical body 430 after passing through the focal plane (the XY plane including the focus F) is reduced.

[0089] The relative distance in the principal axis direction (Z1-Z2 direction) between the focus F of the condenser lens 410 and the tip 431 of the conical body 430 is preferably 30% or less, and more preferably 10% or less, of the focal length LF of the condenser lens 410. In FIG. 12, since the focus F is located in the plane of the planar bottom 432 including the tip 431, the above relative distance is 0 (zero). Although scattering and reflection may occur when light is emitted from the tip 431 of the conical body 430, by positioning the tip 431 in the vicinity of the focus F, this influence can be minimized.

[0090] Using the emission length LE, the diameter DT in terms of a circle of the bottom 432 on the tip 431 side of the conical body 430, the refractive index N1 of the conical body 430, and the refractive index N2 of the substance (air in this embodiment) located around the side surface 434 of the conical body 430, the inclination angle (side surface inclination angle θc) of the side surface 434 of the conical body 430 with respect to the principal axis direction (Z1-Z2 direction) is preferably within the range represented by the following formula (1). θc < 90° - arctan(DT / LE) - arcsin(N2 / N1) (1)

[0091] When the above formula (1) is satisfied, light passing through the pyramidal body 430 along an optical path not along the principal axis direction (Z1-Z2 direction) can be efficiently totally reflected by the side surface 434 of the pyramidal body 430. Note that FIG. 12 shows the angle θb expressed as arctan(DT / LE). Light passing through an optical path whose tilt angle with respect to the optical axis OA direction (optical axis reference incident angle θa) is greater than angle θb can be blocked by the through-hole 422. Furthermore, arcsin(N2 / N1) is the critical angle θx at the side surface 434 of the pyramidal body 430. Using these angles, the above formula (1) can be expressed as the following formula (2). θc<90°-θb-θx (2)

[0092] 12(b), in order to totally reflect light whose incident optical axis LA is aligned with the optical axis OA direction at the side surface 434 of the pyramidal body 430, the side surface inclination angle θc should be smaller than the inclination angle θc0 (= 90° - θx) of the surface 430S0 with respect to the main axis direction (Z1-Z2 direction) as the normal line, which is a line NA0 inclined at the critical angle θx with respect to the main axis direction (Z1-Z2 direction). In other words, θc < θc0 (= 90° - θx) should be satisfied.

[0093] Here, even if light has an optical axis reference incident angle θa of 0° and an incident optical axis along the optical axis OA direction, when the light is irradiated onto the convex surface 411 of the condenser lens 410 with a predetermined area, light other than light passing through the optical axis OA is refracted at the convex surface 411, and therefore the optical path passing through the cone-shaped body 430 is not along the optical axis OA direction. Of such light having an optical axis reference incident angle θa other than 0°, even if light having an incident angle exceeding the critical angle θx with respect to the normal NA0 (i.e., the optical axis reference incident angle θa is less than 90°-θx) enters the cone-shaped body 430, it is totally reflected at the side surface 434 located on the surface 430S0 and cannot proceed toward the through-hole 422 side (Z1-Z2 direction).

[0094] In contrast, when light having an incident angle equal to or smaller than the critical angle θx with respect to the normal NA0 (i.e., when the optical axis-referenced incident angle θa is equal to or larger than 90°-θx) passes through the inside of the cone-shaped body 430, the light is not totally reflected at the side surface 434 located on the surface 430S0. Therefore, part of the light incident on the cone-shaped body 430 passes through the cone-shaped body 430 and travels toward the through-hole 422 (the Z2 side in the Z1-Z2 direction). Of such light traveling toward the through-hole 422 (the Z2 side in the Z1-Z2 direction), light traveling along an optical path with an optical axis-referenced incident angle θa larger than the optical path L0, where the optical axis-referenced incident angle θa is angle θb, can be blocked by the through-hole 422.

[0095] Therefore, when the side inclination angle θc is the above-mentioned inclination angle θc0, light passing through an optical path in which the optical axis reference incident angle θa is in the range from 0° to angle θb passes through the cone-shaped body 430 without being totally reflected by the side surface 434 of the cone-shaped body 430, and the passed light is not blocked by the through hole 422 of the aperture 420 and reaches the light receiving element 210.

[0096] For such light (light passing through the interior of the pyramidal body 430 along an optical path with an optical axis-referenced incident angle θa ranging from 0° to θb), total reflection can be achieved at the side surface 434 of the pyramidal body 430 by making the side surface inclination angle θc smaller than the above-mentioned inclination angle θc0. Specifically, as shown in FIG. 12(b), the side surface inclination angle θc should be smaller than the inclination angle θc1 (=90°-(θb+θx)) of the surface 430S, whose normal is a line NA inclined at an angle (θb+θx) with respect to the principal axis direction (Z1-Z2 direction). In other words, θc<θc1 (=90°-θb-θx) should be satisfied.

[0097] From the above, the relationship between the side surface 434 and the bottom 432 of the pyramidal body 430 can be defined as follows: That is, among the surfaces located on the tip 431 side (the Z2 side in the Z1-Z2 direction) of the pyramidal body 430, the surface with a side surface inclination angle of θc1 or more can be defined as the bottom 432, and the surface located on the incident side in the main axis direction (the Z1 side in the Z1-Z2 direction) of the bottom 432 can be defined as the side surface 434. The bottom 432 guides light that has entered the pyramidal body 430 from the incident side in the main axis direction (the Z1 side in the Z1-Z2 direction) to the output side in the main axis direction (the Z2 side in the Z1-Z2 direction) without total reflection, and guides it to the light receiving element 210. It is preferable that the optical axis reference incident angle θa of light that passes through the bottom 432 and is guided to the light receiving element 210 satisfies the following formula (3) using the circular equivalent diameter DT of the bottom 432 on the tip 431 side (Z2 side in the Z1-Z2 direction) of the cone-shaped body 430. θa <arctan((DT / 2) / LE) (3)

[0098] A light-reflecting member may be attached to the side surface 434 of the cone-shaped body 430. In the optical member 500 shown in FIG. 12( a), a reflective layer 435 is provided on the X1 side of the side surface 434 of the cone-shaped body 430 in the X1-X2 direction. The reflective layer 435 may be provided over the entire circumferential surface of the side surface 434 of the cone-shaped body. Specific examples of the reflective layer 435 include a metal material layer such as an aluminum layer. The reflective layer 435 can stably increase the reflectance of the side surface 434 regardless of the shape of the cone-shaped body 430. Furthermore, the side surface 434 and the bottom surface 432 can be easily distinguished. That is, the side surface 434 is provided with the reflective layer 435 and reflects light passing through the interior of the cone-shaped body 430, while the bottom surface 432 is provided with the reflective layer 435 and reflects light passing through the interior of the cone-shaped body 430 on the Z2 side in the Z1-Z2 direction, where the reflective layer 435 is not provided and light passing through the interior of the cone-shaped body 430 is transmitted to the outside of the cone-shaped body 430.

[0099] The side surface 434 of the cone-shaped body 430 may be composed of a surface other than a smooth surface, as long as it has the optical function of reflecting light passing through the interior of the cone-shaped body 430, similar to a smooth surface. For example, the side surface 434 may be composed of a rough surface having irregularities with dimensions less than the wavelength of the incident light, preferably less than 1 / 4 the wavelength of the light, or may be composed of a rough surface having irregular irregularities with in-plane lengths ranging from roughness (up to about several tens of μm) to waviness (down to about submillimeters). Alternatively, the side surface 434 may be composed of a surface having a predetermined periodicity or regularity ranging from roughness to waviness, such as a surface shape such as a sine curve, a peak-valley shape, or a step shape.

[0100] FIG. 13(a) is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical element according to a second example of the second embodiment of the present invention. FIG. 13(b) is a view from the Z-axis direction illustrating the arrangement of each component of the optical element in FIG. 13(a). The basic configuration of an optical sensor 2010 including an optical element 510 according to the second embodiment of the present invention shown in FIG. 10 is similar to that of the optical sensor 2000 according to the first example of the second embodiment. That is, the optical element 510 according to the second example is equipped with an optical element 510 and a light receiving device 200. Compared to the optical element 500 according to the first example, the optical element 510 according to the second example differs in that it includes a translucent optical element 440 in which a condenser lens 410 and a cone-shaped body 430 are integrated, and an aperture 420 is disposed between the translucent optical element 440 and the light receiving element 210 of the light receiving device 200. The optical element 510 has fewer components than the optical element 500, and therefore may have superior assembly productivity.

[0101] FIG. 14 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical element according to a third example of the second embodiment of the present invention. The basic configuration of an optical sensor 2020 including an optical element 520 according to the third example of the second embodiment of the present invention shown in FIG. 14 is similar to that of the optical sensor 2010 according to the second example. That is, the optical element 520 includes a light-receiving device 200 and a translucent optical element 440. In the optical element 520 according to the third example, the apex 431 of the cone-shaped body 430 of the translucent optical element 440 is located closer to the exit side (Z2 side in the Z1-Z2 direction) of the aperture 420 in the main axis direction than to the entrance side (Z1 side in the Z1-Z2 direction) in the main axis direction. This allows the thickness of the optical element 520 in the main axis direction (Z1-Z2 direction) to be thin. From the viewpoints of miniaturization, high integration, and suppressing the influence of stray light, it is preferable that the thickness of the optical element 520 in the main axis direction (Z1-Z2 direction) be small.

[0102] In the optical member 520, the tip 431 of the cone-shaped body 430 is located inside the through-hole 422. As a result, light emitted from the cone-shaped body 430 is efficiently guided into the through-hole 422, and unnecessary light is removed. In this specification, unnecessary light refers to light that should not reach the light receiving element 210, specifically, light with an optical reference incident angle that does not satisfy the above formula (3). When light emitted from the cone-shaped body 430 reaches the Z1 side of the light-blocking member 421 in the Z1-Z2 direction, it may be reflected by the light-blocking member 421 toward the Z1 side in the Z1-Z2 direction. Such reflected light causes unnecessary light. When the tip 431 of the cone-shaped body 430 is located inside the through-hole 422, unnecessary light due to light reflected by the light-blocking member 421 is not generated in principle.

[0103] In the optical member 520, similarly to the optical members 500 and 510 according to the other examples of this embodiment, the focal point F of the condensing lens 410 is located at the bottom 432 including the tip 431 of the cone-shaped body 430. When the tip 431 of the cone-shaped body 430 is located inside the through-hole 422, the distance LS from the focal point F to the surface of the light receiving element 210 on the Z1 side in the Z1-Z2 direction is shortened. Because the width (width in the X1-X2 direction) of the light receiving element 210 and the diameter DL of the condensing lens 410 are the same as those in the optical members 500 and 510, the focal length LF is set shorter than in the optical members 500 and 510. In other words, by positioning the tip 431 of the cone-shaped body 430 inside the through-hole 422, it is possible to reduce the length of the light-transmitting optical element 440 in the Z1-Z2 direction, which facilitates the miniaturization and low-profile of the optical sensor 2020.

[0104] In addition, when the tip 431 of the pyramidal body 430 is located inside the through-hole 422 as in the optical element 520, it is preferable that the exit length LE is equal to or greater than the through-hole diameter DH, instead of the penetration thickness LH being equal to or greater than the through-hole diameter DH. The exit length LE is the relative distance in the main axis direction (Z1-Z2 direction) between the focal point F and the opening of the through-hole 422 closest to the light receiving element 210 (i.e., the opening on the Z2 side in the Z1-Z2 direction). A portion of the through-hole 422 corresponding to the difference (LH - LE) obtained by subtracting the exit length LE from the penetration thickness LH is located closer to the Z1 side in the Z1-Z2 direction than the tip 431 of the pyramidal body 430. Therefore, this portion does not function effectively to block unwanted light emitted from the optical element 520. However, it may function to block unwanted light that has passed through the side surface 434 of the pyramidal body 430.

[0105] 15 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a fourth example of the second embodiment of the present invention. The basic configuration of an optical sensor 2030 including an optical member 530 according to the fourth example of the second embodiment of the present invention shown in FIG. 15 is similar to that of the optical sensor 2020 according to the third example. That is, the optical sensor 2030 includes an optical member 520 having a translucent optical element 440 and a light receiving device 200, and the tip 431 of the cone 430 of the translucent optical element 440 is located inside the through-hole 422 of the aperture 420. The length in the Z1-Z2 direction of the translucent optical element 440 is similar to that of the optical member 520.

[0106] The optical member 530 according to the fourth example differs from the optical member 520 in that the light-transmitting optical element 440 is fixed to the aperture 420 with a light-transmitting adhesive material (transparent adhesive 450). That is, the transparent adhesive 450, which is a type of light-transmitting member, is in contact with the side surface 434 of the cone-shaped body 430 of the light-transmitting optical element 440 on the Z2 side in the Z1-Z2 direction. Using the transparent adhesive 450 may make it easier to fix the positional relationship between the light-transmitting optical element 440 and the aperture 420.

[0107] Here, the transparent adhesive 450, which is a type of translucent material, contacts the side surface 434 of the cone-shaped body 430 but does not adhere to the tip 431 of the cone-shaped body 430. This increases the amount of light emitted from the tip 431 of the cone-shaped body 430. When using the transparent adhesive 450, attention should be paid to its refractive index. If the refractive index of the transparent adhesive 450 is closer to the refractive index of the translucent optical element 440 than to the refractive index of air, the critical angle θx of total reflection increases. This increases the likelihood that unwanted light having an incident optical axis with a relatively small optical-axis-reference incident angle θa will not be properly reflected by the side surface 434 of the cone-shaped body 430 and will reach the light receiving element 210. In this case, the ratio (LP / DB) of the height LP of the cone corresponding to the cone 430 to the equivalent circular diameter DB of the base of the cone should be increased to reduce the side surface inclination angle θc.

[0108] 16 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a fifth example of the second embodiment of the present invention. The basic configuration of an optical sensor 2040 including an optical member 540 according to the fifth example of the second embodiment of the present invention shown in FIG. 16 is similar to that of the optical sensor 2030 according to the third example. That is, the optical sensor 2040 includes an optical member 540 having a translucent optical element 440 and a light receiving device 200, and the tip 431 of the cone 430 of the translucent optical element 440 is located inside the through-hole 422 of the aperture 420. The length in the Z1-Z2 direction of the translucent optical element 440 is similar to that of the optical member 520.

[0109] In contrast to optical member 520, optical member 540 according to the fifth example has a contact region CR where aperture 420 contacts side surface 434 of cone-shaped body 430. This makes it easy to control the positional relationship between aperture 420 and cone-shaped body 430. Because optical member 540 has contact region CR, thickness LT of aperture 420 is greater than penetration thickness LH, and exit length LE is smaller than penetration thickness LH.

[0110] 17 is a cross-sectional view in the XZ plane illustrating an optical sensor including an optical member according to a sixth example of the second embodiment of the present invention. The basic configuration of an optical sensor 2050 including an optical member 550 according to the sixth example of the second embodiment of the present invention shown in FIG. 17 is similar to that of the optical sensor 2010 according to the second example. That is, the optical sensor 2050 includes an optical member 550 having a translucent optical element 440 and a light receiving device 200, and the apex 431 of the cone-shaped body 430 of the translucent optical element 440 is located closer to the incident side in the principal axis direction (the Z1 side in the Z1-Z2 direction) than the through-hole 422 of the aperture 420. The length of the translucent optical element 440 in the Z1-Z2 direction is similar to that of the optical member 510.

[0111] The optical member 540 according to the sixth example differs from the optical member 510 in that a transmissive film 460, which is a type of transmissive member, is disposed between the transmissive optical element 440 and the aperture 420. In this embodiment, the transmissive film 460 abuts against the transmissive optical element 440 and the aperture 420, and functions as a spacer that controls the relative distance between them. Therefore, in the transmissive optical element 440, it is easy to control the positional relationship between the aperture 420 and the cone-shaped body 430. Examples of transmissive materials that make up the transmissive film 460 include polycarbonate, polyethylene terephthalate, and acrylic resin. The transmittance of the transmissive film 460 may be adjusted by including a coloring material (dye, pigment) in the transmissive material.

[0112] Furthermore, when the distance between the condenser lens 410 and the light-receiving element 210 becomes relatively long due to the positioning of the transmissive film 460 between the light-transmitting optical element 440 and the aperture 420, the curvature of the convex surface 411 of the light-transmitting lens 410 increases, which may improve the shape processability. When the transmissive film 460 is disposed between the light-transmitting optical element 440 and the aperture 420 without changing the distance between the condenser lens 410 and the light-receiving element 210, for example, the height LP of the cone corresponding to the cone 430 may be made relatively small, and this change in the shape of the cone 430 may contribute to improving the moldability of the light-transmitting optical element 440.

[0113] (Third embodiment) Conventionally, a collimator array can be fabricated by bundling a plurality of translucent columnar optical fibers and fixing (bundling) the resulting fiber bundle. In one specific example, the optical fibers constituting the collimator array have a circular core cross section with an inner diameter of 10 μm and a length in the major axis direction of 150 μm. Calculations of the incident light controllability of such a collimator array reveal that the transmittance is 100% when the incident angle is 5° and 7.40% when the incident angle is 15°. The total reflection condition is set to 5°, and the reflectance at the cladding is set to 50%.

[0114] The aspect ratio (longitudinal length / circular equivalent diameter of core cross section) of the optical fibers that make up this collimator array is 15, and it is not easy to extend structures with such a large aspect ratio along the optical axis. It is also not easy to align the longitudinal axes of a large number of such structures along the optical axis. Variations in the arrangement of these structures directly affect the incident light control described above. Therefore, to properly control the optical properties of the collimator array, extremely strict process control is required for the manufacturing of the individual optical fibers and the bundling process.

[0115] In the above-mentioned collimator array, if an attempt is made to miniaturize it while maintaining the aspect ratio, the cross-sectional area of ​​the optical fiber core becomes smaller, resulting in a decrease in the aperture ratio. Since a decrease in aperture ratio reduces the absolute value of the transmitted light amount, in order to ensure the transmitted light amount, it is necessary to increase the size of the light source and the amount of irradiated light. Such a solution places a limit on the miniaturization of the optical sensor. Therefore, simply miniaturizing the collimator array according to the prior art will also limit the miniaturization of the optical sensor.

[0116] 18 is a diagram illustrating the structure of an optical element included in a collimator array according to a third embodiment of the present invention. In an optical element 800 according to the third embodiment of the present invention, as shown in FIG. 18, an optical fiber consisting of a core 801 and a cladding 802 has a tapered structure, and the cross-sectional area of ​​the core 801 gradually decreases along the optical axis direction. The total reflection condition of the optical fiber is set to an angle larger than the tilt angle of the incident light to be transmitted. This allows appropriate angle control of the incident light even if the length of the collimator in the optical axis direction is shortened.

[0117] The optical characteristics of the optical element 800 made of an optical fiber having a tapered structure were calculated under the following conditions. Incidence side diameter 18μm Output side diameter 5μm Taper angle 6.2° Fiber length 60μm Total reflection condition 25° Core refractive index 1.50 Cladding refractive index 1.36 Cladding reflectivity 50°

[0118] The calculation results for incident light control under these conditions show that the transmittance is 94.8% when the incident angle is 5°, and 7.0% when the incident angle is 15°.

[0119] Therefore, it was theoretically confirmed that the optical element 800 according to this embodiment can obtain the same optical characteristics as an optical fiber without a tapered structure, even at a length that is half or less.

[0120] There are no particular limitations on the method for manufacturing a collimator array including the optical element 800 according to this embodiment. By employing the method described below, it may be possible to efficiently manufacture the collimator array according to this embodiment.

[0121] The method for manufacturing a collimator array according to this embodiment includes the following steps. (Step 1) A clad array having a plurality of recesses corresponding to the cores is formed on a substrate by an imprinting method. (Step 2) The core material is filled into the recesses of the cladding array by a doctor blade method to reduce the fluidity of the core material, thereby forming a collimator array.

[0122] FIG. 19 is an explanatory diagram of a manufacturing method according to this embodiment. A roll-to-roll method can be used in step 1. FIG. 20 is an explanatory diagram of step 1 using the roll-to-roll method. A roll of laminate 850 is prepared, in which a UV-curable resin layer 852 is laminated on a substrate 851 made of a release film that is transparent to ultraviolet light. This roll is unwound, and a stamper roll 860 having a stamper 861 with a plurality of recesses each having an inverted shape of the clad is pressed against the UV-curable resin layer 852 of the laminate 850 to roll-form protrusions corresponding to the clad. At the same time, ultraviolet light is irradiated from a UV lamp 870 provided on the substrate 851 side ( FIG. 19( a) ). The UV-curable resin layer with the transferred shape is cured, thereby obtaining a sheet 830 in which a clad array 831 is formed on the substrate 851 ( FIG. 19( b) ).

[0123] Step 2 can be performed using a doctor blade method. FIG. 21 is an explanatory diagram of step 2 using the doctor blade method. A sheet 830 is unwound and passed over a back roll 880, which is in contact with a liquid receiving pan 881 that holds a liquid material (core material CM) for forming cores. By passing between the liquid receiving pan 881 and the back roll 880, the core material CM comes into contact with the side of the sheet 830 where the clad array 831 is provided, and the core material CM fills the numerous recesses of the clad array 831. A knife 882, positioned at a predetermined gap from the back roll 880, removes a portion of the core material CM, thereby controlling the amount of core material CM attached to the sheet 830 ( FIG. 19( c)). By applying an appropriate process (e.g., heating) to the sheet 830 with an appropriate amount of core material CM attached, the fluidity of the core material CM is reduced to form cores 832, and a collimator array 820 is obtained in which numerous optical elements 800 having a tapered structure as shown in FIG. 18 are arranged ( FIG. 19( d)).

[0124] When step 1 is performed using an imprinting method, if an acrylic resin commonly used in imprinting methods is used as the constituent material of the UV-curable resin layer 852, there is a concern that when the acrylic resin is cured by the UV lamp 870 and the protrusions of the stamper 861 are removed from the recesses having a depth of approximately 60 μm, the protrusions may collide with the cured acrylic resin, destroying the cured product. Therefore, in the manufacturing method according to this embodiment, it is preferable to use a soft material that has a certain degree of flexibility in a cured state as the constituent material of the UV-curable resin layer 852. One example of such a material is dimethylpolysiloxane (PDMS). The refractive index of PDMS is approximately 1.50, and in this case, a silicone resin with a refractive index of approximately 1.36 may be used as the core material CM.

[0125] (Fourth embodiment) The optical element 900 according to the fourth embodiment of the present invention, like the optical element 100 according to the first embodiment, includes a plurality of lens optical systems each having a lens and two shielding members arranged along the optical axis of the lens.

[0126] An optical member 900 according to the fourth embodiment of the present invention can be manufactured by the manufacturing method shown in FIGS.

[0127] First, lenses 912 are arranged in an array on one surface of a substrate 911 made of a transparent material such as polyethylene terephthalate (PET) by processing a transparent optical material using an imprinting method, thereby obtaining a lens array 910 (Figure 22(a)).

[0128] A resist layer made of a negative photosensitive agent is formed on the surface of the substrate 911 opposite to the side on which the lenses 912 are provided, and exposure light EL, which is light parallel to the optical axis of the lenses 912, is irradiated from the side on which the lenses 912 are provided in the lens array 910. The exposure light EL is refracted by the lenses 912 and converged and emitted from the lens array 910. This converged exposure light EL hardens only the portions of the resist layer that are transmitted by the convergent light path. In this way, an optical material layer 913 having a shape corresponding to the convergent light path is formed on the surface of the substrate 911 opposite to the side on which the lenses 912 are provided (FIG. 22(b)).

[0129] A black coating 914 is formed on the surface of the base material 911 on which the optical material layer 913 is provided so as to cover the optical material layer 913 (FIG. 22(c)).

[0130] Next, ablation light AL, which is parallel to the optical axis of the lens 912, is irradiated from the side of the lens array 910 where the lenses 912 are provided. This ablation light AL is also converged by the lens array 910, forming a convergent optical path on the optical material layer 913 side. Since this convergent optical path is basically the same as the convergent optical path formed by the exposure light EL, the ablation light AL emitted from the lens array 910 passes through the optical material layer 913 and is irradiated onto the black coating 914 laminated on the tip of the optical material layer 913. As a result, the black coating 914 laminated on the tip of the optical material layer 913 is removed, forming an opening 915. In this way, a first light-shielding portion 916 is formed on the side of the lens array 910 opposite the side where the lenses 912 are provided (FIG. 22(d)).

[0131] An optical material layer 917 of a predetermined thickness is formed to cover the first light-shielding portion 916 (FIG. 23(e)). An optical material layer 918 having a shape corresponding to the convergent optical path is disposed on the surface of the optical material layer 917 by a process similar to that shown in FIGS. 22(b) to 22(d). Black paint 919 is then formed to cover these layers. An ablation light AL, which is parallel to the optical axis of the lens 912, is used to remove the black paint 919 located at the tip of the optical material layer 918, thereby forming an opening 920 (FIG. 23(f)). In this way, a second light-shielding portion 921 is formed distal to the first light-shielding portion 916 when viewed from the lens array 910. Finally, a protective layer 922 is formed to protect the second light-shielding portion 921, thereby obtaining the optical element 900 shown in FIG. 23(g).

[0132] In this way, by using the lens array 910 to focus the exposure light EL and the ablation processing light AL for forming the light-shielding portion of the optical element 900, it becomes possible to autonomously align the formed light-shielding portion (first light-shielding portion 916, second light-shielding portion 921), thereby achieving increased controllability of the opening of the light-shielding portion. [Explanation of symbols]

[0133] 10: Lens section 11: Lens 11a, 11b, 11c, 11d: exposure lenses 15: Lens optical system 20: Light blocking section 21: First light-shielding part 21h: 1st through hole 21a, 21b, 21c, 21d: Exposed first through hole 21ra, 21rb, 21rc, 21rd: First notch 22: Second light-shielding part 22h: 2nd through hole 22a, 22b, 22c, 22d: second through holes of interest 22ra, 22rb, 22rc, 22rd: Second notch 30:Connection part 30S: End face of wall-shaped body in the first direction 31: Wall-like body 40: Optical adjustment material 50: Light receiving element 51: Housing 100, 101: Optical components 100p: structure 200: Light receiving device 210: Light receiving element 220: Substrate 300: Optical unit 410: Condenser lens 411: Convex 420: Aperture 421: Light-shielding material 422: Through hole 430: Cone 430S, 430S0: Surface 431: Point 432: Bottom 434: Side 435: Reflective layer 440: Translucent optical element 450: Transparent adhesive 460:Transparent film 500, 500X, 510, 520, 530, 540, 550: Optical components 800: Optical elements 801, 832: Core 802: Clad 820: Collimator array 830: Sheet 831: Clad array 850: Laminate 851: Base material 852:UV curing resin layer 860: Stamperol 861: Stamper 870: UV lamp 880: Back Roll 881: Liquid receiving pan 882: Knife 900: Optical components 910: Lens array 911: Base material 912: Lens 913: Optical material layer 914: Black painted 915 :Aperture 916: First light-shielding part 917: Optical material layer 918: Optical material layer 919: Black painted 920 :Aperture 921: Second light-shielding part 922 :Protective layer 1000, 2000, 2001, 2010, 2020, 2030, 2040, 2050: Optical sensor BT: Blackening treatment area CP1: First connection part CP2: Second connection part FS: Frame shape GP: Gap HA1: 1st central axis HA2: 2nd central axis SD1: 1st position deviation SD2: Second position deviation AA: Through shaft AL: Light for ablation processing CM: Core material CR:Contact area DB: Equivalent diameter DH:Through hole diameter DL: Caliber DT: Equivalent diameter EL: Light for exposure F: Focus L0:Light path L1:X1 side optical path L1O: Optical path L1R: 1st reflected optical path L2:X2 side optical path L2O: light path L2R: 2nd reflected optical path LA: Incident optical axis LE: Output length LF: Focal length LG: Gap LH: Penetration thickness LP: Height LS: Distance LT: Thickness N1: Refractive index N2: Refractive index NA0, NA: normal OA: optical axis Pc: Convergence point Qd11: Square lens Qd21: 1st quadrilateral Qd22 :Second quadrilateral R1: 1st reflection point R2: 2nd reflection point SP: Split plane VS: Virtual Vertex θa: Optical axis reference angle of incidence θb :Angle θc: Side inclination angle θc0, θc1: Inclination angles θx: critical angle

Claims

1. a lens unit including a plurality of lenses each having an optical axis along a first direction; a light-shielding portion having a plurality of through holes provided at positions corresponding to the optical axes of the plurality of lenses; An optical element comprising: the light-shielding portion has a first light-shielding portion that is sheet-shaped and relatively close to the lens portion, and a second light-shielding portion that is sheet-shaped and relatively far from the lens portion, a connecting portion having a wall-like body positioned around the light-shielding portion and extending in the first direction, the connecting portion connecting the first light-shielding portion and the second light-shielding portion; The connecting portion is integrally formed with the light blocking portion. An optical element characterized by:

2. The optical member according to claim 1 , wherein the light-shielding portion and the connecting portion are formed by plating.

3. The optical member according to claim 1 , wherein the first light-shielding portion and the second light-shielding portion are connected to the side surfaces of the wall-shaped body at their respective peripheral edges.

4. The optical member according to claim 1 , wherein the connecting portion is joined to a peripheral edge portion of the lens portion at an end surface of the wall-shaped body in the first direction.

5. The optical member according to claim 4 , wherein the lens portion is made of a resin-based material.

6. The optical member according to claim 1 , wherein the connecting portion is provided so as to surround the periphery of the light blocking portion when viewed from the first direction.

7. The optical member according to claim 1 , wherein the connecting portion includes a plurality of the wall-like bodies arranged with gaps therebetween in a direction intersecting the first direction.

8. The optical member according to claim 1 , wherein the light-shielding portion is subjected to a blackening treatment.

9. 9. An optical sensor comprising: the optical member according to claim 1; and a light receiving element provided on the optical axis on the opposite side of the light blocking portion from the lens portion.

10. A biosensor comprising the optical sensor according to claim 9.

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