Optical element, optical unit, optical device, method for adjusting optical element, and method for manufacturing optical element

Abstract

To provide a technique advantageous for adjusting the position and posture of an optical element with high accuracy.SOLUTION: An optical element includes a plurality of optical surfaces. At least one optical surface of the plurality of optical surfaces has: a main surface extending in a longitudinal direction and a short side direction; and a mark, including a recess portion or a protrusion portion and extending in the longitudinal direction of the main surface.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to the art of optical elements. [Background technology]

[0002] Patent document 1 discloses a detection device that provides an inspection mark on an optical element and detects the focusing condition under which light emitted from an objective lens becomes a parallel beam based on the image of the inspection mark detected by an image detector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-148437 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, optical devices including optical elements having multiple optical surfaces have come to be used in various fields such as imaging, observation, measurement, information, etc. In optical elements having multiple optical surfaces, the position and orientation of the optical elements need to be adjusted with high precision in order to achieve optical performance according to design values.

[0005] The present disclosure provides a technique that is advantageous for adjusting the position and orientation of an optical element with high precision. [Means for solving the problem]

[0006] A first aspect of the present disclosure is an optical element comprising a plurality of optical surfaces, at least one of the plurality of optical surfaces having a main surface extending in a longitudinal direction and a lateral direction, and a mark including a concave or convex portion extending in the longitudinal direction of the main surface.

[0007] A second aspect of the present disclosure is a method for manufacturing an optical element, comprising the steps of preparing a base material and processing the base material, wherein in the processing of the base material, an optical surface having a main surface extending in a longitudinal direction and a lateral direction and a mark including a concave or convex portion extending in the longitudinal direction of the main surface is formed by cutting. Effect of the Invention

[0008] The present disclosure provides a technique that is advantageous for adjusting the position and orientation of an optical element with high precision. [Brief description of the drawings]

[0009] [Figure 1] 1A is a perspective view of the optical element according to the first embodiment, and FIG. 1B is a schematic diagram showing an example of an optical image of reflected light from marks on each mirror surface of the optical element according to the first embodiment. [Diagram 2] 1A is an explanatory diagram of a mirror surface according to the first embodiment, and FIG. 1B and FIG. 1C are cross-sectional views of a portion of the optical element according to the first embodiment. [Diagram 3] 5(a) and 5(b) are explanatory views of a method for forming a mirror surface according to the first embodiment. [Figure 4] 6(a) and 6(b) are explanatory views of a method for forming a mirror surface according to a modified example of the first embodiment. [Diagram 5] 1A is a diagram for explaining misalignment in the X-axis direction of the optical element according to the first embodiment, and FIGS. 1B and 1C are diagrams for explaining the shift of an optical image projected onto a pixel array due to the misalignment in the X-axis direction of the optical element according to the first embodiment. [Figure 6] 1A is a diagram for explaining positional deviation in the Y-axis direction of the optical element according to the first embodiment, and FIGS. 1B and 1C are diagrams for explaining deviation of an optical image projected onto a pixel array due to positional deviation in the Y-axis direction of the optical element according to the first embodiment. [Figure 7]1A is a diagram for explaining misalignment in the Z-axis direction of the optical element according to the first embodiment, and FIGS. 1B and 1C are diagrams for explaining the shift of an optical image projected onto a pixel array due to the misalignment in the Z-axis direction of the optical element according to the first embodiment. [Figure 8] 1A is a diagram for explaining a positional deviation about the X-axis of the optical element according to the first embodiment, and FIG. 1B is a diagram for explaining a shift in an optical image projected onto a pixel array due to a positional deviation about the X-axis of the optical element according to the first embodiment. [Figure 9] 1A is a diagram for explaining a positional deviation about the X-axis of the optical element according to the first embodiment, and FIG. 1B is a diagram for explaining a shift in an optical image projected onto a pixel array due to a positional deviation about the X-axis of the optical element according to the first embodiment. [Figure 10] 1A is a diagram for explaining a misalignment of the optical element according to the first embodiment about the Y axis, and FIG. 1B is a diagram for explaining a misalignment of an optical image projected onto a pixel array due to a misalignment of the optical element according to the first embodiment about the Y axis. [Figure 11] 1A is a diagram for explaining a misalignment of the optical element according to the first embodiment about the Y axis, and FIG. 1B is a diagram for explaining a misalignment of an optical image projected onto a pixel array due to a misalignment of the optical element according to the first embodiment about the Y axis. [Figure 12] 1A is a diagram for explaining a misalignment of the optical element according to the first embodiment around the Z axis, and FIG. 1B is a diagram for explaining a misalignment of an optical image projected onto a pixel array due to a misalignment of the optical element according to the first embodiment around the Z axis. [Figure 13] 1A is a diagram for explaining a misalignment of the optical element according to the first embodiment around the Z axis, and FIG. 1B is a diagram for explaining a misalignment of an optical image projected onto a pixel array due to a misalignment of the optical element according to the first embodiment around the Z axis. [Figure 14] 10(a) is an explanatory diagram of an optical unit according to a second embodiment, and (b) is an explanatory diagram of an optical unit according to a modified example of the second embodiment. [Figure 15]1A is an explanatory diagram of an optical system according to a third embodiment, and FIG. 1B is an explanatory diagram of an optical system according to a fourth embodiment. [Figure 16] FIG. 1 shows a table of experimental results in an example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the drawings. The following embodiments are illustrative of preferred configurations of the present disclosure, and for example, those skilled in the art can appropriately modify the detailed configurations without departing from the spirit of the present disclosure. In addition, in the drawings referred to in the following description of the embodiments, elements denoted by the same reference numbers have the same functions unless otherwise noted.

[0011] [First embodiment] FIG. 1(a) is a perspective view of an optical element 10 according to a first embodiment. The optical element 10 includes a mirror array 150 having a plurality of mirror surfaces. The mirror surface is an example of an optical surface. Two or more of the plurality of mirror surfaces have a mark, which will be described later. The two or more mirror surfaces face in different directions. In the first embodiment, the two or more mirror surfaces are four mirror surfaces 11a, 11b, 11c, and 11d. That is, the optical element 10 has four mirror surfaces 11a to 11d. The four mirror surfaces 11a to 11d are preferably arranged in a matrix. Hereinafter, a case in which the optical element 10 has four mirror surfaces 11a to 11d will be described, but the present invention is not limited thereto, and the optical element 10 may have five or more mirror surfaces.

[0012] The optical element 10 is supported by a support member (not shown) so that the position and orientation of the optical element 10 can be adjusted relative to the support member (not shown), and thus the optical element 10 is positioned relative to the support member.

[0013] Optical element 10 has a base 110 on which mirror surfaces 11a to 11d are formed, and a supported portion 12 connected to base 110. Supported portion 12 is supported by a supporting member (not shown) so that the positions and attitudes of mirror surfaces 11a to 11d are adjustable.

[0014] An orthogonal coordinate system of X-axis, Y-axis, and Z-axis is defined with respect to a support member that supports the optical element 10. Since the mirror surfaces 11a to 11d face in different directions, light incident on the mirror surfaces 11a to 11d from the same direction is reflected by the mirror surfaces 11a to 11d in different directions. The incident direction of light on the optical element 10 is defined as the +Z direction. The direction opposite to the +Z direction is defined as the -Z direction. The +Z direction is the positive direction of the Z axis, and the -Z direction is the negative direction of the Z axis. Two directions perpendicular to the Z axis direction are defined as the X-axis direction and the Y-axis direction. The X-axis direction and the Y-axis direction are perpendicular to each other. The positive direction of the X axis is defined as the +X direction. The negative direction of the X axis is defined as the -X direction. The positive direction of the Y axis is defined as the +Y direction. The negative direction of the Y axis is defined as the -Y direction.

[0015] Mirror surfaces 11a-11d are formed at the tip of base 110 in the -Z direction. Light (light rays) reflected by mirror surfaces 11a-11d are projected at different positions on the XY plane. By adjusting the position and orientation of optical element 10, the positions of the optical images projected by mirror surfaces 11a-11d can be adjusted.

[0016] The mirror surfaces 11a to 11d have optical axes that are individually designed to be oriented in different directions. That is, the mirror surfaces 11a to 11d are designed to be at different angles relative to a reference plane, for example, the XY plane. The accuracy of the position and orientation of the optical element 10 affects the accuracy of the optical performance of an optical device that includes the optical element 10.

[0017] Fig. 1(b) is a schematic diagram showing an example of an optical image of reflected light from marks 15 on each of the mirror surfaces 11a to 11d of the optical element 10 according to the first embodiment. Note that in Fig. 1(b), the optical image of reflected light from the main surface 13 is omitted.

[0018] 2(a) is an explanatory diagram of the mirror surface 11 according to the first embodiment. Here, each of the mirror surfaces 11a to 11d has the same configuration, and each of the mirror surfaces 11a to 11d will be described as the mirror surface 11. Here, an orthogonal coordinate system with the X0 axis, Y0 axis, and Z0 axis based on the mirror surface 11 is defined. The long direction of the mirror surface 11 is the X0 axis direction, and the short direction of the mirror surface 11 is the Y0 axis direction. The X0 axis direction and the Y0 axis direction are mutually orthogonal. The direction orthogonal to the X0 axis direction and the Y0 axis direction is the Z0 axis direction.

[0019] The mirror surface 11 has a main surface 13 and a mark 15. The main surface 13 is a surface that extends in the X0-axis direction and the Y0-axis direction, and is a flat surface in the first embodiment. Of the surfaces included in the mirror surface 11, the main surface 13 has the largest area. Note that the main surface 13 may be a curved surface.

[0020] The mark 15 is formed on the optically effective surface. The mark 15 is a mark for adjusting the position and orientation of the optical element 10. That is, the mark 15 is a mark that can be used to adjust the position and orientation of the optical element 10. The mark 15 is a mark that extends in the X0 axis direction from a first end to a second end of the two ends in the X0 axis direction of the main surface 13. The mark 15 is preferably formed so as to extend linearly in the X0 axis direction. In the first embodiment, the mark 15 extending in the X0 axis direction is formed in the center of the main surface 13 in the Y0 axis direction. The mark 15 is a stripe-like mark formed so as to be continuous in the X0 axis direction. The number of marks 15 on one mirror surface 11 is preferably one. Here, the center includes not only the case where the center of the mark 15 passes through the center, but also the case where at least a part of the mark 15 passes through the center.

[0021] Although not shown, the optical element 10 may further include, in addition to the mirror surfaces 11a-11d, mirror surfaces that do not have the marks 15. Furthermore, the optical element 10 may further include, in addition to the mirror surfaces 11a-11d, mirror surfaces that have the marks 15. These mirror surfaces separate from the mirror surfaces 11a-11d may face in the same direction as any of the mirror surfaces 11a-11d.

[0022] 2(b) and 2(c) are cross-sectional views of a portion of the optical element 10 according to the first embodiment. The mark 15 may be a concave portion 151 recessed in the Z0 axis direction (negative direction of the Z0 axis) with respect to the main surface 13 as shown in FIG. 2(b), or may be a convex portion 152 protruding in the Z0 axis direction (positive direction of the Z0 axis) with respect to the main surface 13 as shown in FIG. 2(c). The depth of the concave portion 151 with respect to the main surface 13 in the Z0 axis direction is D1. The height of the convex portion 152 with respect to the main surface 13 in the Z0 axis direction is H1. The width of the mark 15 in the Y0 axis direction is W1, and the width of the mirror surface 11, i.e., the main surface 13 in the Y0 axis direction is W0. The concave portion 151 has a concave cross-sectional shape. The convex portion 152 has a convex cross-sectional shape. The concave or convex shape is an inspection shape for inspecting the position and orientation of the optical element 10. In Figures 2(b) and 2(c), the surfaces other than the recessed portion 151 and the protruding portion 152 are flat, but recessed portions having a smaller depth than the recessed portion 151 and protruding portions having a smaller height than the protruding portion 152 may be formed.

[0023] The following describes a method for manufacturing the optical element 10. The mirror surfaces 11a to 11d of the optical element 10 are formed by the same method, and the following describes a method for forming one of the mirror surfaces 11a to 11d, mirror surface 11.

[0024] 3(a) and 3(b) are explanatory views of a method for forming the mirror surface 11 according to the first embodiment. In the first embodiment, the mirror surface 11 is formed by cutting using one cutting tool 131.

[0025] First, a base material 100 is prepared. The base material 100 is, for example, a metal base material. Next, the base material 100 is processed. The base material 100 is cut to form the mirror surface 11 of the optical element 10. In the first embodiment, the mirror surface 11 is formed by cutting the base material 100 with a cutting tool 131 having a cutting edge with a width narrower than the width of the mirror surface 11 in the Y0-axis direction.

[0026] The mirror surface 11 may have a non-optical surface having a width sufficiently narrower than the width of the mirror surface 11 in the Y0-axis direction. Alternatively, the mirror surface 11 may have a non-optical surface having a width sufficiently narrower than the width of the cutting edge of the cutting tool 131 in the Y0-axis direction.

[0027] In the first embodiment, as shown in Figures 3(a) and 3(b), the mirror surface 11 is formed by reciprocating the cutting tool 131 in the X0-axis direction relative to the base material 100. Either the cutting tool 131 or the base material 100 may be moved in the machine tool. On the outward path, in which the cutting tool 131 is moved relatively in the X0-axis direction, half of the mirror surface 11 in the Y0-axis direction is formed. Then, on the return path, in which the cutting tool 131 is moved relatively in the X0-axis direction, the remaining half of the mirror surface 11 in the Y0-axis direction is formed.

[0028] On the return path in which the cutting tool 131 is moved relatively in the X0-axis direction, the cutting tool 131 is rotated 180° around an axis extending in the Z0-axis direction with respect to the mirror surface 11 to perform cutting. As a result, by performing cutting with one cutting tool 131, a mark 15 that becomes a recess 151 or a protrusion 152 is formed in the center of the mirror surface 11 in the Y0-axis direction.

[0029] When the mark 15 to be formed is a recess 151, the forward path and the return path of the cutting tool 131 are overlapped to form the recess 151 extending in the X0 axis direction in the overlapped portion.

[0030] When the mark 15 to be formed is a convex portion 152, by leaving a gap without overlapping the outward path and return path of the cutting tool 131, a convex portion 152 extending in the X0 axis direction can be formed in the gap.

[0031] 4(a) and 4(b) are explanatory diagrams of a method for forming the mirror surface 11 according to a modified example of the first embodiment. In the modified example of the first embodiment, the mirror surface 11 is formed by cutting using two cutting tools 131 and 132.

[0032] 4(a) and 4(b), in a modification of the first embodiment, the cutting tools 131 and 132 are each moved in one direction along the X0 axis, for example, in the negative direction along the X0 axis, to form the mirror surface 11. What is moved in the machine tool may be either the cutting tools 131 and 142 or the base material 100.

[0033] In cutting using cutting tool 131, half of mirror surface 11 in the Y0-axis direction is formed. Then, in cutting using cutting tool 132, the remaining half of mirror surface 11 in the Y0-axis direction is formed. As a result, mark 15 that becomes recess 151 or protrusion 152 is formed in the center of mirror surface 11 in the Y0-axis direction.

[0034] When the mark 15 to be formed is a recess 151, the path of the cutting tool 131 and the path of the cutting tool 132 are overlapped with each other, so that the recess 151 extending in the X0 axis direction can be formed in the overlapping portion.

[0035] When the mark 15 to be formed is a convex portion 152, by leaving a gap without overlapping the path of the cutting tool 131 and the path of the cutting tool 132, a convex portion 152 extending in the X0 axis direction can be formed in the gap.

[0036] The following describes a method for adjusting the position and orientation of the optical element 10. Prepare the optical element 10. In the first embodiment, a light source (not shown) and an image sensor (not shown) are disposed at intervals from the optical element 10 in the -Z direction.

[0037] A light source (not shown) irradiates each of mirror surfaces 11a to 11d with light in the +Z direction. As shown in Fig. 1(d), the light image of the light reflected from mark 15 on mirror surface 11a is designated as 111a, the light image of the light reflected from mark 15 on mirror surface 11b is designated as 111b, the light image of the light reflected from mark 15 on mirror surface 11c is designated as 111c, and the light image of the light reflected from mark 15 on mirror surface 11d is designated as 111d.

[0038] The image sensor (not shown) is a sensor for inspecting the position and orientation of the optical element 10, that is, a sensor for detecting the marks 15 on each of the mirror surfaces 11a to 11d. The position and orientation of the optical element 10 is adjusted based on an image that is an inspection result of the image sensor. The area indicated by the dashed line is, for example, a pixel array 501 as a light receiving surface of the image sensor. The pixel array 501 of the image sensor includes pixel groups 511a, 511b, 511c, and 511d indicated by the dotted line. The pixel group 511a is a pixel group corresponding to the reference position of the optical image 111a, the pixel group 511b is a pixel group corresponding to the reference position of the optical image 111b, the pixel group 511c is a pixel group corresponding to the reference position of the optical image 111c, and the pixel group 511d is a pixel group corresponding to the reference position of the optical image 111d. The pixel groups 511a to 511d have the same predetermined length in the X-axis direction, which is the longitudinal direction. That is, the pixel groups 511a, 511b, 511c, and 511d each have the same predetermined number of pixels in the X-axis direction.

[0039] When the optical element 10 is adjusted to a reference position and orientation, the optical images 111a-111d overlap with the pixel groups 511a-511d, respectively. In this case, the longitudinal direction of the optical images 111a-111d is the X-axis direction, and the length of the optical images 111a-111d in the X-axis direction is a predetermined length. That is, when the optical element 10 is adjusted to a reference position and orientation, the optical images 111a-111d are projected onto the pixel groups 511a-511d, respectively.

[0040] In the first embodiment, light is irradiated onto the optical element 10 from a light source, and the position and orientation of the optical element 10 are adjusted based on the optical image of the reflected light reflected from the marks 15 on each of the mirror surfaces 11a to 11d. At this time, in the first embodiment, an image processing device (not shown) can detect the position and orientation of the optical element 10 by analyzing the captured image captured by the image sensor.

[0041] FIG. 5(a) is a diagram for explaining the positional shift in the X-axis direction of the optical element 10 according to the first embodiment, and FIG. 5(b) and FIG. 5(c) are diagrams for explaining the shift of the optical image projected onto the pixel array 501 due to the positional shift in the X-axis direction of the optical element 10 according to the first embodiment.

[0042] Fig. 5(b) shows a case where the optical element 10 has shifted in the +X direction with respect to the reference position, and Fig. 5(c) shows a case where the optical element 10 has shifted in the -X direction with respect to the reference position.

[0043] When optical element 10 shifts in the +X direction relative to the reference position, mark 15 on each of mirror surfaces 11a-11d shifts in the +X direction relative to the corresponding reference position, and therefore each of optical images 111a-111d, which is the reflected light of mark 15 on each of mirror surfaces 11a-11d, shifts in the +X direction relative to each of pixel groups 511a-511d. The length of each of optical images 111a-111d in the X-axis direction, which is the longitudinal direction, is the predetermined length described above.

[0044] Similarly, when optical element 10 shifts in the -X direction relative to the reference position, mark 15 on each of mirror surfaces 11a-11d shifts in the -X direction relative to the corresponding reference position, and therefore each of optical images 111a-111d, which is reflected light from mark 15 on each of mirror surfaces 11a-11d, shifts in the -X direction relative to each of pixel groups 511a-511d. The length of each of optical images 111a-111d in the X-axis direction, which is the longitudinal direction, is a predetermined length.

[0045] Figure 6(a) is a diagram for explaining the positional shift in the Y-axis direction of the optical element 10 according to the first embodiment, and Figures 6(b) and 6(c) are diagrams for explaining the shift in the optical image projected onto the pixel array 501 due to the positional shift in the Y-axis direction of the optical element 10 according to the first embodiment.

[0046] Fig. 6(b) shows a case where the optical element 10 has shifted in the +Y direction with respect to the reference position, and Fig. 6(c) shows a case where the optical element 10 has shifted in the -Y direction with respect to the reference position.

[0047] When optical element 10 shifts in the +Y direction relative to the reference position, mark 15 on each of mirror surfaces 11a-11d shifts in the +Y direction relative to the corresponding reference position, and therefore each of optical images 111a-111d, which is reflected light from mark 15 on each of mirror surfaces 11a-11d, shifts in the +Y direction relative to each of pixel groups 511a-511d. The length of each of optical images 111a-111d in the X-axis direction, which is the longitudinal direction, is a predetermined length.

[0048] Similarly, when optical element 10 shifts in the -Y direction relative to the reference position, mark 15 on each of mirror surfaces 11a-11d shifts in the -Y direction relative to the corresponding reference position, and therefore each of optical images 111a-111d, which is reflected light from mark 15 on each of mirror surfaces 11a-11d, shifts in the -Y direction relative to each of pixel groups 511a-511d. The length in the X-axis direction, which is the longitudinal direction of each of optical images 111a-111d, is a predetermined length.

[0049] Figure 7(a) is a diagram for explaining the positional shift in the Z-axis direction of the optical element 10 according to the first embodiment, and Figures 7(b) and 7(c) are diagrams for explaining the shift in the optical image projected onto the pixel array 501 due to the positional shift in the Z-axis direction of the optical element 10 according to the first embodiment.

[0050] Fig. 7(b) shows a case where the optical element 10 has shifted in the +Z direction relative to the reference position, and Fig. 7(c) shows a case where the optical element 10 has shifted in the -Z direction relative to the reference position.

[0051] When the optical element 10 shifts in the +Z direction relative to the reference position, each of the mirror surfaces 11a-11d of the optical element 10 moves away from the light source (not shown) and the pixel array 501 in the +Z direction. Since the mark 15 on each of the mirror surfaces 11a-11d shifts in the +Z direction relative to the corresponding reference position, the position of each of the optical images 111a-111d, which is the reflected light of the mark 15 on each of the mirror surfaces 11a-11d, shifts in a direction away from a predetermined center point. Furthermore, since the optical path becomes longer, each of the optical images 111a-111d at the position of the pixel array 501 also expands. That is, the length in the X-axis direction, which is the longitudinal direction of each of the optical images 111a-111d, becomes longer than a predetermined length.

[0052] When the optical element 10 shifts in the -Z direction relative to the reference position, each of the mirror surfaces 11a-11d of the optical element 10 moves closer to the light source and pixel array 501 (not shown) in the -Z direction. Since the mark 15 on each of the mirror surfaces 11a-11d shifts in the -Z direction relative to the corresponding reference position, the position of each of the optical images 111a-111d, which are the reflected light of the mark 15 on each of the mirror surfaces 11a-11d, shifts in a direction closer to the center of the XY plane. Furthermore, since the optical path is shortened, each of the optical images 111a-111d at the position of the pixel array 501 also shrinks. That is, the length in the X-axis direction, which is the longitudinal direction of each of the optical images 111a-111d, becomes shorter than a predetermined length.

[0053] 8(a) and 9(a) are diagrams for explaining the attitude shift of the optical element 10 according to the first embodiment about the X-axis, and Fig. 8(b) and Fig. 9(b) are diagrams for explaining the shift of the optical image projected on the pixel array 501 due to the attitude shift of the optical element 10 according to the first embodiment about the X-axis. Fig. 8(a) and Fig. 8(b) show a case where the optical element 10 is tilted clockwise around the X-axis with respect to the reference attitude, with the +X direction being positive. Fig. 9(a) and Fig. 9(b) show a case where the optical element 10 is tilted counterclockwise around the X-axis with respect to the reference attitude, with the +X direction being positive.

[0054] 8(a), when the optical element 10 is tilted clockwise around the X-axis as viewed in the +X direction with respect to the reference posture, each of the mirror surfaces 11a-11d of the optical element 10 is tilted clockwise around the X-axis as viewed in the +X direction with respect to the light source (not shown) and the pixel array 501. Therefore, as shown in FIG. 8(b), the positions of the optical images 111a-111d, which are the reflected light of the marks 15 on the mirror surfaces 11a-11d, are shifted in the +Y direction. In addition, the optical path of the reflected light on the mirror surfaces 11a and 11d on the +Y side becomes longer, and the optical path of the reflected light on the mirror surfaces 11b and 11c on the -Y side becomes shorter, so that the optical images 111a and 111d at the position of the pixel array 501 are enlarged and the optical images 111b and 111c are reduced. That is, the length in the X-axis direction which is the longitudinal direction of each of the optical images 111a and 111d is longer than a predetermined length, and the length in the X-axis direction which is the longitudinal direction of each of the optical images 111b and 111c is shorter than a predetermined length.

[0055] 9(a), when the optical element 10 is tilted counterclockwise around the X-axis as viewed in the +X direction with respect to the reference posture, each of the mirror surfaces 11a-11d of the optical element 10 is tilted counterclockwise around the X-axis as viewed in the +X direction with respect to the light source (not shown) and the pixel array 501. Therefore, as shown in FIG. 9(b), the positions of the optical images 111a-111d, which are the reflected light of the marks 15 on each of the mirror surfaces 11a-11d, are shifted in the -Y direction. In addition, the optical path of the reflected light on the mirror surfaces 11a and 11d on the +Y side is shortened, and the optical path of the reflected light on the mirror surfaces 11b and 11c on the -Y side is lengthened, so that the optical images 111a and 111d at the position of the pixel array 501 are reduced, and the optical images 111b and 111c are enlarged. That is, the length in the X-axis direction which is the longitudinal direction of each of the optical images 111a and 111d is shorter than a predetermined length, and the length in the X-axis direction which is the longitudinal direction of each of the optical images 111b and 111c is longer than a predetermined length.

[0056] Fig. 10(a) and Fig. 11(a) are diagrams for explaining the attitude shift of the optical element 10 according to the first embodiment about the Y axis, and Fig. 10(b) and Fig. 11(b) are diagrams for explaining the shift of the optical image projected on the pixel array 501 due to the attitude shift of the optical element 10 according to the first embodiment about the Y axis. Fig. 10(a) and Fig. 10(b) show a case where the optical element 10 is tilted clockwise around the Y axis with respect to the reference attitude, with the +Y direction being positive. Fig. 11(a) and Fig. 11(b) show a case where the optical element 10 is tilted counterclockwise around the Y axis with respect to the reference attitude, with the +Y direction being positive.

[0057] 10(a), when the optical element 10 is tilted clockwise around the Y axis when viewed in the +Y direction with respect to the reference posture, each of the mirror surfaces 11a to 11d of the optical element 10 is tilted clockwise around the Y axis when viewed in the +Y direction with respect to the light source (not shown) and the pixel array 501. Therefore, as shown in FIG. 10(b), the positions of the optical images 111a to 111d, which are the reflected light of the marks 15 on each of the mirror surfaces 11a to 11d, are shifted in the -X direction. In addition, the optical path of the reflected light on the mirror surfaces 11c and 11d on the -X side becomes longer, and the optical path of the reflected light on the mirror surfaces 11a and 11b on the +X side becomes shorter, so that the optical images 111c and 111d at the position of the pixel array 501 are enlarged and the optical images 111a and 111b are reduced. That is, the length in the X-axis direction which is the longitudinal direction of each of the optical images 111c and 111d is longer than a predetermined length, and the length in the X-axis direction which is the longitudinal direction of each of the optical images 111a and 111b is shorter than a predetermined length.

[0058] 11(a), when the optical element 10 is tilted counterclockwise around the Y axis when viewed in the +Y direction with respect to the reference posture, each of the mirror surfaces 11a to 11d of the optical element 10 tilts counterclockwise around the Y axis when viewed in the +Y direction with respect to the light source and pixel array 501 (not shown). Therefore, as shown in FIG. 11(b), the positions of the optical images 111a to 111d, which are the reflected light of the marks 15 on each of the mirror surfaces 11a to 11d, are shifted in the +X direction. In addition, the optical path of the reflected light on the mirror surfaces 11c and 11d on the -X side becomes shorter, and the optical path of the reflected light on the mirror surfaces 11a and 11b on the +X side becomes longer, so that the optical images 111c and 111d at the position of the pixel array 501 shrink and the optical images 111a and 111b expand. That is, the length in the X-axis direction which is the longitudinal direction of each of the optical images 111c and 111d becomes shorter than a predetermined length, and the length in the X-axis direction which is the longitudinal direction of each of the optical images 111a and 111b becomes longer than a predetermined length.

[0059] Fig. 12(a) and Fig. 13(a) are diagrams for explaining the attitude shift of the optical element 10 according to the first embodiment about the Z axis, and Fig. 12(b) and Fig. 13(b) are diagrams for explaining the shift of the optical image projected on the pixel array 501 due to the attitude shift of the optical element 10 according to the first embodiment about the Z axis. Fig. 12(a) and Fig. 12(b) show a case where the optical element 10 is rotated clockwise around the Z axis with respect to the reference attitude, with the +Z direction being positive. Fig. 13(a) and Fig. 13(b) show a case where the optical element 10 is rotated counterclockwise around the Z axis with respect to the reference attitude, with the +Z direction being positive.

[0060] 12(a), when the optical element 10 rotates clockwise around the Z axis when viewed in the +Z direction with respect to the reference posture, each of the mirror surfaces 11a-11d of the optical element 10 rotates clockwise around the Z axis when viewed in the +Z direction with respect to the light source and pixel array 501 (not shown). Therefore, as shown in FIG. 12(b), each of the optical images 111a-111d, which are the reflected light of the mark 15 on each of the mirror surfaces 11a-11d, rotates clockwise around the Z axis when viewed in the +Z direction. The longitudinal direction of each of the optical images 111a-111d is inclined with respect to the X-axis direction, and the longitudinal length of each of the optical images 111a-111d is a predetermined length.

[0061] 13(a), when the optical element 10 rotates counterclockwise around the Z axis when viewed in the +Z direction with respect to the reference posture, each of the mirror surfaces 11a-11d of the optical element 10 rotates counterclockwise around the Z axis when viewed in the +Z direction with respect to the light source and pixel array 501 (not shown). Therefore, as shown in FIG. 13(b), each of the optical images 111a-111d, which are the reflected light of the marks 15 on each of the mirror surfaces 11a-11d, rotates counterclockwise around the Z axis when viewed in the +Z direction. The longitudinal direction of each of the optical images 111a-111d is inclined with respect to the X-axis direction, and the longitudinal length of each of the optical images 111a-111d is a predetermined length.

[0062] As described above, according to the first embodiment, when the optical element 10 is placed on a support member (not shown), by observing the optical images 111a-111d projected by the marks 15 included on the mirror surfaces 11a-11d, it is possible to determine the deviation of the position and orientation of the optical element 10 from the reference position and orientation, thereby making it possible to easily adjust the position and orientation of the optical element 10 to the reference position and orientation. Specifically, by observing the positions, sizes, and inclinations of the optical images 111a-111d, it is possible to determine the shifts in the X, Y, and Z-axis directions, the tilts about the X and Y axes, and the rotation about the Z axis of the optical element 10, thereby making it possible to easily adjust the position and orientation of the optical element 10 to the reference position and orientation.

[0063] Although the case has been described where the position and orientation of the optical element 10 is inspected by irradiating the optical element 10 with light and projecting the reflected light onto an image sensor, the present invention is not limited to this. For example, the position and orientation of the optical element 10 may be inspected by directly observing the mark 15 included in the mirror surface 11 with a differential interference microscope. In this case, it is sufficient that at least one of the multiple mirror surfaces 11 of the optical element 10 includes the mark 15. By using the differential interference microscope, the position and orientation of the optical element 10 with respect to the reference surface can be easily inspected when the optical element 10 is installed.

[0064] [Second embodiment] A second embodiment of the present disclosure will be described. In the following, elements with the same reference symbols as those in the first embodiment will have substantially the same configurations and functions as those described in the first embodiment unless otherwise specified, and differences from the first embodiment will be mainly described.

[0065] Fig. 14(a) is an explanatory diagram of an optical unit 50 according to the second embodiment. The optical unit 50 includes the optical element 10 described in the first embodiment, an optical element 20 different from the optical element 10, a support member 401 that supports the optical element 10, and a support member 402 that supports the optical element 20. The optical element 10 is an example of a first optical element, and the optical element 20 is an example of a second optical element. The supported portion 12 of the optical element 10 shown in Fig. 1 is supported by the support member 401 so that the position and attitude of the optical element 10 can be adjusted. The support members 401 and 402 are positioned relative to each other.

[0066] The optical element 20 has a mirror array 250 that has the same number of mirror surfaces as the mirror array 150 of the optical element 10. Since the mirror array 150 has four mirror surfaces, the mirror array 250 has four mirror surfaces.

[0067] The optical element 20 is disposed at a distance from the optical element 10 in the -Z direction opposite to the +Z direction in which light is incident on the optical element 10. The multiple mirror surfaces of the mirror array 250 of the optical element 20 reflect the reflected light (light rays) from the multiple mirror surfaces of the mirror array 150 of the optical element 20 in the +Z direction. The +Z direction is an example of a first direction, and the -Z direction is an example of a second direction. The position and orientation of the optical element 10 is adjusted with respect to the support member 401 so that the multiple reflected light rays (light rays) reflected by the mirror array 250 are emitted in the +Z direction parallel to each other.

[0068] In the optical element 10 of the optical unit 50 having such a configuration, as in the first embodiment, by observing the position, size, and tilt of the optical image corresponding to the mark 15 contained in the reflected light of the optical element 10, the shift in the X, Y, and Z axes, the tilt about the X and Y axes, and the rotation about the Z axis of the optical element 10 can be obtained, and thus the position and posture of the optical element 10 can be easily adjusted to the reference position and posture.

[0069] Moreover, the optical element 20 is disposed on the support member 402 so as to face the optical element 10. The behavior of the multiple light beams emitted from the optical element 20 due to the shift in the XYZ-axis directions is the same as the behavior of the multiple light beams emitted from the optical element 10, and the shift in the XYZ-axis directions of the optical element 20 can be inspected in the same manner as in the first embodiment. The behavior of the multiple light beams emitted from the optical element 20 due to the rotation around the Z-axis is the same as the behavior of the multiple light beams emitted from the optical element 10, and the rotation around the Z-axis of the optical element 20 can be inspected in the same manner as in the first embodiment. On the other hand, the tilt of the optical element 20 around the XY-axis can be inspected using a differential interference microscope.

[0070] [Modification of the second embodiment] The number of optical elements included in the optical unit is not limited to two, and may be three or more. Fig. 14(b) is an explanatory diagram of an optical unit 50A according to a modified example of the second embodiment. The optical unit 50A includes an optical element 10, a support member 401 that supports the optical element 10, an optical element 20, a support member 402 that supports the optical element 20, an optical element 30, a support member 403 that supports the optical element 30, an optical element 40, and a support member 404 that supports the optical element 40. The optical element 10 is an example of a first optical element, the optical element 20 is an example of a second optical element, the optical element 30 is an example of a third optical element, and the optical element 40 is an example of a fourth optical element.

[0071] Optical element 30 has a mirror array 350 that has the same number of mirror surfaces as mirror array 150 of optical element 10. Since mirror array 150 has four mirror surfaces, mirror array 350 has four mirror surfaces. Optical element 40 has a mirror array 450 that has the same number of mirror surfaces as mirror array 150 of optical element 10. Since mirror array 150 has four mirror surfaces, mirror array 450 has four mirror surfaces.

[0072] The optical element 30 is disposed away from the optical element 10 in the +Z direction. The optical element 40 is disposed between the optical elements 10 and 30 in the Z-axis direction. The mirror array 450 of the optical element 40 reflects the reflected light from the mirror array 350 of the optical element 30 in the +Z direction.

[0073] That is, the multiple reflected light beams (light rays) reflected by the mirror array 150 of the optical element 10 are incident on the mirror array 250 of the optical element 20 and are reflected by the mirror array 250. The multiple reflected light beams (light rays) reflected by the mirror array 250 of the optical element 20 are incident on the mirror array 350 of the optical element 30 and are reflected by the mirror array 350. The multiple reflected light beams (light rays) reflected by the mirror array 350 of the optical element 30 are incident on the mirror array 450 of the optical element 40 and are reflected by the mirror array 450. The multiple reflected light beams (light rays) reflected by the mirror array 350 of the optical element 30 are output from the exit surface of the optical unit 50A.

[0074] In the modified example of the second embodiment, the positions and orientations of the optical elements 10 to 40 can be inspected at the position of the reflected light emitted from the emission surface of the optical unit 50A. It is possible to inspect the positions and orientations of the optical elements 10 to 40 individually at the position of the light image corresponding to the mark 15 on the mirror surface 11 of the optical element 10, but it is also possible to inspect the positions and orientations of the optical elements 10 to 40 at the position of the light beam imaged at the focal position of the reflected light by reflecting light on the mirror surfaces of the multiple optical elements 10 to 40.

[0075] The optical elements 10 and 30 reflect light in the -Z direction, and the behavior of the position change of the optical image corresponding to the mark 15 is the same for both. The optical elements 20 and 40 reflect light in the -Z direction, and the behavior of the position change of the optical image corresponding to the mark 15 is the same for both. Therefore, like the second embodiment, the positions and orientations of the optical elements 10 to 40 can be inspected.

[0076] [Third embodiment] A third embodiment of the present disclosure will be described below. In the following, elements having the same reference symbols as those in the first or second embodiment will have substantially the same configurations and functions as those described in the first or second embodiment unless otherwise specified, and differences from the first or second embodiment will be mainly described.

[0077] 15(a) is an explanatory diagram of an optical system 1000 according to a third embodiment. The optical system 1000 includes an observation device 61 and an optical device 500. The optical device 500 includes an optical unit 50, a connection unit 52, and an imaging device 53.

[0078] The observation device 61 is a light collecting device for spectroscopically analyzing light arriving from an observation object 62, and is an astronomical telescope when the observation object 62 is a celestial body. The light collecting method of the observation device 61 may be either a refractive or reflective method, but it is preferable that attenuation due to transmission and reflection of light in the wavelength band to be observed is within a range that does not interfere with spectroscopic analysis.

[0079] The imaging device 53 is a digital camera having an image sensor. The imaging device 53 captures an optical image collected by the observation device 61 and outputs an observation image. In the third embodiment in which spectroscopic analysis is performed, the optical unit 50 is disposed in front of the imaging device 53, i.e., between the observation device 61 and the imaging device 53.

[0080] When the focal position of the observation device 61 connected to the imaging device 53 when performing only normal observation is different from the focal position of the optical unit 51, it is preferable to place the connection part 52 between the observation device 61 and the optical unit 51. Depending on the wavelength to be spectroscopically analyzed, a filter that passes a predetermined wavelength band may be placed in front of the optical unit 51 or in front of the observation device 61. Spectroscopic analysis is an analysis that performs wavelength analysis by the light diffraction phenomenon. Depending on the diffraction angle by the diffraction grating, light of different wavelengths may overlap on the light receiving part of the imaging device 53. For this reason, a filter is used to limit the wavelength band. The diffraction grating may be provided with a diffraction function in any of the optical elements constituting the optical unit 50, or may be placed between the optical unit 50 and the imaging device 53.

[0081] In spectroscopic analysis, an observation device 61 collects light emitted from an observation target 62 from an aperture onto the eyepiece side. The aperture corresponds to the object side, that is, the objective side.

[0082] The collected light is introduced into the optical unit 50 via the connection part 52. The light introduced into the optical unit 50 is split by the mirror array 150 of the optical element 10, and is output from the output surface via the optical element 20. The light output from the output surface of the optical unit 50 is wavelength-resolved by a diffraction grating that diffracts a predetermined wavelength band, and is imaged by the imaging device 53. As a result, the observation image emitted from the observation object 62 is directly spectroscopically analyzed by the observation device 61.

[0083] In the optical device 500, the optical unit 50 may be replaced with an optical unit 50A.

[0084] [Fourth embodiment] A fourth embodiment of the present disclosure will be described. In the following, elements with the same reference symbols as those in the first to third embodiments have substantially the same configurations and functions as those described in the first to third embodiments unless otherwise specified, and differences from the first to third embodiments will be mainly described.

[0085] 15B is an explanatory diagram of an optical system 1000A according to the fourth embodiment. The optical system 1000A includes an optical device 500A. The optical device 500A is an analysis device 71, and includes an optical unit 50, a lens 54, and an imaging device 53.

[0086] The analysis device 71 is a device that analyzes light arriving from the analysis target 72 by dispersing it into wavelengths, and is typified by a spectral camera, for example. When observing a visible light image of the analysis target 72 together with the analysis results of the analysis device 71, an imaging device (not shown) that images the analysis target 72 can be installed in parallel with the analysis device 71.

[0087] The light emitted from the object to be analyzed 72 is introduced into the optical unit 50, and if focusing is required, a lens 54 such as a camera lens is provided. The lens 54 provided on the object side of the analysis device 71 focuses the light from the object to be analyzed 72 on the optical unit 51 side and introduces it into the optical unit 50.

[0088] The light introduced into the optical unit 50 is split by the mirror array 150 of the optical element 10 of the optical unit 50, and is emitted from the emission surface via the optical element 20. The light emitted from the emission surface of the optical unit 50 is wavelength-resolved by a diffraction grating that diffracts a predetermined wavelength band, and is imaged by the imaging device 53. As a result, the observation image emitted from the analysis target 72 is directly spectroscopically analyzed by the analysis device 71.

[0089] It should be noted that miniaturization is possible by providing a diffraction function to any of the optical elements 10, 20 constituting the optical unit 50. In addition, in the analysis device 71 which is the optical instrument 500A, the optical unit 50 may be replaced with an optical unit 50A.

[0090] When the analysis target 72 is a product moving on a conveyance line, it is possible to use the analysis device 71, which is optical equipment 500A, when simultaneously analyzing a visible light image and a spectroscopic analysis image. By making the analysis device 71 into a unit, it is also possible to move the analysis device 71 within a factory or device, and by moving the analysis device 71 with a mobile device such as an unmanned aerial vehicle, it is possible to perform spectroscopic analysis in various spaces, even outdoors.

[0091] [Example] An example corresponding to the first embodiment will be described below. In the example, an optical element 10 shown in Fig. 1 was manufactured. The width of the mirror surface 11 in the short direction was set to 1.0 mm, and the length in the long direction was set to 50 mm.

[0092] The mirror surface 11 was formed by cutting. The cutting tool used for cutting was a symmetrical tool, a diamond tool with a width of 0.1 mm. The cutting tool was moved in the longitudinal direction to cut the base material, forming the mirror surface 11. A mark 15 of a predetermined width was formed in the center of the width of the mirror surface 11 in the short side direction.

[0093] Fig. 16 is a diagram showing a table of experimental results in the examples. In the examples, six samples 1 to 6 were created. Fig. 16 shows the shape of the mark 15 in each of the samples 1 to 6. Note that in Fig. 16, the shape of the mark 15 is the depth in the case of a concave portion, and the shape of the mark 15 is the height in the case of a convex portion.

[0094] The deviation of the position and orientation of the optical element 10 from the reference position and orientation was inspected using the mark 15. In addition, the optical performance of the mirror surface 11 with the mark 15 was evaluated. The position and orientation inspection results and the evaluation results of the optical performance are shown as "A" and "B." Both "A" and "B" are within the permissible range for use as the optical element 10 in an optical unit, etc. "A" is better than "B."

[0095] The marks 15 in Samples 1 to 5 are recesses 151, and the mark 15 in Sample 6 is a protrusion 152.

[0096] In Samples 1 to 6, the optical element 10 was shifted 0.005 mm in the Y-axis direction from the reference position, and rotated 0.0023° clockwise from the reference position when viewed in the +Z direction.

[0097] In samples 1, 2, 4, 5 and 6, it was possible to easily inspect that the optical element 10 had rotated by approximately 0.0023° in terms of the rotation angle. By using the mark 15 provided at the center of the mirror surface 11 as a reference, it was possible to stably inspect the position and orientation of the optical element 10 even in the mirror array 150 in which the mirror surface 11, which is the optically effective surface, is tilted. In addition, although parallax occurs due to the tilt of the mirror array 150 at the ridge line of the mirror array 150 and the width of the mirror surface 11, which is the optically effective surface, it was possible to easily inspect the position and orientation. Therefore, the inspection result of the position and orientation in samples 1, 2, 4, 5 and 6 was "A".

[0098] On the other hand, in sample 3, the width of mark 15 is 5 μm, which is narrower than the width of marks 15 in other samples 1, 2, 4, 5 and 6, which is 10 μm to 800 μm, so the light image corresponding to mark 15 is small and the position and orientation inspection result is “B”.

[0099] In addition, in Samples 1, 3, 4, and 6, the optical image obtained from the mirror surface 11 was free of distortion and was favorable, and therefore the evaluation result of the optical performance was "A."

[0100] On the other hand, in sample 2, the depth of the recess 151 was 80 nm, which was deeper than the depth of the recess 151 of 50 nm or the height of the protrusion 152 of 50 nm in the other samples 1, 3, 4, and 6. As a result, the optical image was more distorted than in the other samples 1, 3, 4, and 6, and the optical evaluation was "B."

[0101] In addition, in sample 5, the width of mark 15 was 800 μm, which was wider than the width of marks 15 in other samples 1, 3, 4, and 6, which was 10 μm to 500 μm. Therefore, the optical image was more distorted than in other samples 1, 3, 4, and 6, and the optical evaluation was "B".

[0102] From the above results, referring to FIG. 2(a) to FIG. 2(c), when the mark 15 is a recess 151, the depth D1 of the recess 151 relative to the main surface 13 is preferably 50 nm or less. When the mark 15 is a protrusion 152, the height H1 of the protrusion 152 relative to the main surface 13 is preferably 50 nm or less. The width W1 of the mark 15 in the Y0 axis direction is preferably 10 μm or more and 500 μm or less. In other words, the width W1 of the mark 15 in the Y0 axis direction is preferably 1 / 2 or less of the width W0 of the main surface 13 in the Y0 axis direction. The width W1 of the mark 15 in the Y0 axis direction is preferably 1 / 100 or more of the width W0 of the main surface 13 in the Y0 axis direction.

[0103] The present disclosure is not limited to the above-described embodiments, and many modifications of the embodiments are possible within the technical concept of the present disclosure. Furthermore, the effects described in the present embodiment are merely a list of the most preferable effects resulting from the embodiments of the present disclosure, and the effects of the embodiments of the present disclosure are not limited to those described in the present embodiment.

[0104] The disclosure of this specification includes not only what is explicitly described in this specification, but also all matters that can be understood from this specification and the drawings attached hereto. The disclosure of this specification also includes the complement of each individual concept described in this specification. In other words, if this specification contains a statement that "A is B," for example, this specification can be said to disclose that "A is not B," even if the statement that "A is not B" is omitted. This is because when a statement that "A is B" is made, it is assumed that the case in which "A is not B" is taken into consideration.

[0105] The disclosure of the above embodiments includes the following sections.

[0106] (Section 1) A plurality of optical surfaces are provided. At least one of the plurality of optical surfaces is A main surface extending in a longitudinal direction and a lateral direction; A mark including a recess or a protrusion extending in the longitudinal direction of the main surface. An optical element characterized by:

[0107] (Section 2) The at least one optical surface is two or more optical surfaces facing in different directions. 2. The optical element according to item 1,

[0108] (Section 3) The two or more optical surfaces are four or more optical surfaces. 3. The optical element according to item 2,

[0109] (Section 4) The four or more optical surfaces are arranged in a matrix. Item 4. The optical element according to item 3.

[0110] (Section 5) The mark is provided at the center of the main surface in the short side direction. 5. The optical element according to any one of items 1 to 4.

[0111] (Section 6) the mark is the recess, The depth of the recess with respect to the main surface is 50 nm or less. 6. The optical element according to any one of items 1 to 5,

[0112] (Section 7) the mark is the protrusion, The height of the protrusions relative to the main surface is 50 nm or less. 6. The optical element according to any one of items 1 to 5,

[0113] (Section 8) The width of the mark in the short side direction is 10 μm or more and 500 μm or less. 8. The optical element according to any one of items 1 to 7,

[0114] (Section 9) The width of the mark in the short side direction is ½ or less of the width of the main surface in the short side direction. 9. The optical element according to any one of items 1 to 8,

[0115] (Section 10) The optical surface is a mirror surface. 10. The optical element according to any one of items 1 to 9,

[0116] (Section 11) The main surface is a plane. 11. The optical element according to any one of items 1 to 10,

[0117] (Section 12) Further comprising a supported portion supported by the support member. 12. The optical element according to any one of items 1 to 11,

[0118] (Section 13) the mark is a mark for adjusting the position and attitude of the optical element; 13. The optical element according to any one of items 1 to 12,

[0119] (Section 14) The optical element according to any one of items 1 to 13, A support member for supporting the optical element. An optical unit characterized by:

[0120] (Section 15) the support member supports the optical element so as to adjust the position and orientation of the optical element. Item 15. The optical unit according to item 14,

[0121] (Section 16) the optical element is a first optical element, a second optical element that is disposed apart from the first optical element in a second direction opposite to a first direction in which light is incident on the first optical element, and that reflects reflected light from the first optical element in the first direction; 16. The optical unit according to item 14 or 15,

[0122] (Section 17) a third optical element that reflects the reflected light from the second optical element; and a fourth optical element that reflects the reflected light from the third optical element in the first direction, Item 17. The optical unit according to item 16, characterized in that

[0123] (Section 18) An optical unit according to any one of items 14 to 17, and an imaging device that captures an image of the light from the optical unit. An optical instrument characterized by:

[0124] (Section 19) An optical element according to any one of items 1 to 13 is prepared, irradiating the optical element with light, and adjusting the position and orientation of the optical element based on an optical image of the light reflected from the mark; 13. A method for adjusting an optical element comprising the steps of:

[0125] (Section 20) A method for manufacturing an optical element, comprising the steps of: A step of preparing a base material; and processing the base material. In the step of processing the base material, an optical surface having a main surface extending in a longitudinal direction and a lateral direction and a mark including a concave portion or a convex portion extending in the longitudinal direction of the main surface is formed by cutting. A method for producing an optical element comprising the steps of: [Explanation of symbols]

[0126] 10...optical element, 11a...mirror surface (optical surface), 11b...mirror surface (optical surface), 11c...mirror surface (optical surface), 11d...mirror surface (optical surface), 15...mark

Claims

1. Equipped with multiple optical surfaces, Each of the two or more optical surfaces among the plurality of optical surfaces that are oriented in different directions from each other is: Main surfaces extending in the longitudinal and transverse directions, The main surface has a mark including a recess or protrusion extending in the longitudinal direction, An optical element characterized by the following features.

2. The mark extends from the first end to the second end of the two ends in the longitudinal direction of the main surface. The optical element according to feature 1.

3. The two or more optical surfaces are four or more optical surfaces. The optical element according to feature 1.

4. The four or more optical surfaces are arranged in a matrix. The optical element according to feature 3.

5. The main surface has a first portion and a second portion, and the mark is provided between the first portion and the second portion in the short direction. The optical element according to feature 1.

6. The aforementioned mark is the recess, The depth of the recess relative to the main surface is 50 nm or less. The optical element according to feature 1.

7. The aforementioned mark is the aforementioned protrusion, The height of the protrusion relative to the main surface is 50 nm or less. The optical element according to feature 1.

8. The width of the mark in the shorter direction is 10 μm or more and 500 μm or less. The optical element according to feature 1.

9. The width of the mark in the shorter direction is 1 / 2 or less of the width of the main surface in the shorter direction. The optical element according to feature 1.

10. Each of the aforementioned plurality of optical surfaces is a mirror surface. The optical element according to feature 1.

11. The aforementioned main surface is a plane. The optical element according to feature 1.

12. The aforementioned mark is a mark for adjusting the position and orientation of the optical element. The optical element according to feature 1.

13. An optical element according to any one of claims 1 to 12, The system comprises a support member for supporting the optical element, An optical unit characterized by the following features.

14. The support member is configured to support the optical element so that its position and orientation can be adjusted. The optical unit according to feature 13.

15. The optical element is a first optical element, The present invention further comprises a second optical element, which is positioned at a distance from the first optical element in a second direction opposite to the first direction in which light is incident on the first optical element, and is configured to reflect the reflected light from the first optical element in the first direction. The optical unit according to feature 13.

16. A third optical element configured to reflect light reflected from the second optical element, The present invention further comprises a fourth optical element configured to reflect light reflected from the third optical element in the first direction, The optical unit according to feature 15.

17. The optical element comprises a base on which the optical surface is formed and a supported portion connected to the base, The aforementioned base is made of metal. The supported portion is supported by the support member. The optical unit according to feature 13.

18. The optical unit according to claim 13, The system comprises an imaging device configured to capture light from the optical unit, An optical instrument characterized by the following features.

19. Prepare the optical element according to any one of claims 1 to 12, The optical element is irradiated with light, Based on the optical image of the reflected light reflected by the mark, the position and orientation of the optical element are adjusted. A method for adjusting an optical element, characterized by the features described above.

20. A method for manufacturing an optical element, The process of preparing the base material, The process includes a step of processing the base material to form a plurality of optical surfaces, In the process of processing the aforementioned base material, Each of the above-mentioned plurality of optical surfaces, which are oriented in different directions from each other, has a main surface extending in the longitudinal and transverse directions, and a mark including a recess or protrusion extending in the longitudinal direction of the main surface. A method for manufacturing an optical element, characterized by the following:

21. The main surface and / or the optical surface is formed by cutting, A method for manufacturing an optical element according to claim 20, characterized in that it is a method for manufacturing an optical element.

Images