Reflector Assemblies and Optical Modules

Abstract

The reflector assembly (2) includes: a reflector device (20) including a substrate (21) and a movable reflector (22); an optical functional component (13); and a fixed reflector (16) arranged on the opposite side of the reflector device (20) relative to the optical functional component (13). A light passing portion (24) constituting a first portion of an optical path between the beam splitter assembly (3) and the fixed reflector (16) is formed in the reflector device (20). A light transmitting portion (14) constituting a second portion of an optical path between the beam splitter assembly (3) and the fixed reflector (16) is formed in the optical functional component (13). A second surface (21b) of the substrate (21) and a third surface (13a) of the optical functional component (13) are bonded to each other.

Description

[0001] This application is filed on July 6, 2018 、Application No. 201880040988.0 、The name of the invention is Reflector Components and optical modules A divisional application for a patent application. Technical Field

[0002] The invention relates to a reflector assembly and an optical module. Background Art

[0003] As a MEMS (MicroElectroMechanical Systems) device composed of an SOI (Silicon On Insulator) substrate, there is known a mirror device including a substrate and a movable mirror supported on the substrate so as to be movable along the thickness direction of the substrate (for example, see Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent document 1: U.S. Patent Application Publication No. 2008 / 0284078. Summary of the invention

[0007] Technical problem to be solved by the invention

[0008] The above-mentioned reflector device has attracted attention because it can provide high-precision FTIR (Fourier transform infrared spectrometer).

[0009] An object of the present invention is to provide a mirror assembly suitable for compactly configuring a high-precision interference optical system and an optical module including such a mirror assembly.

[0010] Technical solutions to the problem

[0011] A reflector assembly according to one aspect of the present invention comprises: a reflector device including a substrate and a movable reflector, the substrate having a first surface and a second surface on the opposite side to the first surface, the movable reflector being supported on the substrate in a manner movable along a first direction intersecting the first surface; an optical functional component having a third surface opposite to the second surface and a fourth surface on the opposite side to the third surface; and a fixed reflector arranged on the opposite side of the reflector device relative to the optical functional component, a first light passing portion constituting a first part of an optical path between a beam splitter assembly and the fixed reflector being formed in the reflector device, wherein the beam splitter assembly together with the movable reflector and the fixed reflector constitute an interference optical system, a second light passing portion constituting a second part of an optical path between the beam splitter assembly and the fixed reflector being formed in the optical functional component, and the second surface of the substrate and the third surface of the optical functional component being bonded to each other.

[0012] In the reflector assembly, an optical functional component is arranged between the reflector device and the fixed reflector, and the optical functional component is joined to the base of the reflector device. Therefore, the base can be stably held in a state where deformation of the base is suppressed. Therefore, the movable reflector can be operated with high precision in the reflector device. In addition, a first light passing portion constituting the first part of the optical path between the beam splitter assembly and the fixed reflector is formed in the reflector device, and a second light passing portion constituting the second part of the optical path is formed in the optical functional component. Thus, an interference optical system consisting of a beam splitter assembly, a movable reflector and a fixed reflector can be efficiently arranged in space. According to the above description, a high-precision interference optical system can be compactly constructed using the reflector assembly.

[0013] In the reflector assembly according to one aspect of the present invention, the second surface of the base and the third surface of the optical functional component may be bonded to each other by direct bonding, thereby achieving a strong bond between the base of the reflector device and the optical functional component.

[0014] In the reflector assembly according to one aspect of the present invention, the fixed reflector may be formed on the fourth surface of the optical functional component. This can improve the positional accuracy and angular accuracy of the fixed reflector relative to the movable reflector of the reflector device.

[0015] In the reflector assembly of one aspect of the present invention, the optical functional component may further include a fifth surface spaced apart from the reflector device at least in a region facing the movable reflector. Thus, for example, even if the reference position when the movable reflector is reciprocated (vibrated) in the first direction is located on the third surface of the optical functional component, the movable reflector can be prevented from contacting the optical functional component and the movable reflector can be reciprocated in the first direction. In addition, the reference position when the movable reflector is reciprocated in the first direction can be located on the third surface of the optical functional component, which is particularly effective in correcting the optical path difference between the optical path between the beam splitter assembly and the movable reflector and the optical path between the beam splitter assembly and the fixed reflector, as described later.

[0016] In a reflector assembly according to one aspect of the present invention, the reflector device may be configured as follows: the reflector device is configured by a semiconductor substrate, the semiconductor substrate includes a support layer configured by a first semiconductor layer, a device layer configured by a second semiconductor layer, and an intermediate layer configured by an insulating layer between the support layer and the device layer, the second surface of the substrate is the surface of the device layer on the opposite side of the intermediate layer, and the reflector surface of the movable reflector is arranged on the surface of the device layer on the intermediate layer side. In the semiconductor substrate, the device layer is thinner than the support layer, so that, for example, compared to a structure in which the second surface of the substrate (the bonding surface of the optical functional component) is the surface of the support layer on the opposite side of the intermediate layer, and the reflector surface of the movable reflector is arranged on the surface of the device layer on the opposite side of the intermediate layer, the reflector surface of the movable reflector can be arranged closer to the optical functional component. Therefore, for example, the reference position of the movable reflector when it reciprocates in the first direction can be easily located at the third surface of the optical functional component.

[0017] In the reflector assembly of one aspect of the present invention, the fifth surface of the optical functional component may extend to the outer edge of the optical functional component when viewed from the first direction. Thus, even if gas exists in the region between the movable reflector and the fifth surface of the optical functional component, the gas is easily discharged from the region, and the movement of the movable reflector can be suppressed from being hindered by the gas existing in the region.

[0018] In the reflector assembly of one aspect of the present invention, the first light passing portion may be a hole, the second light passing portion may be a light transmitting portion for correcting an optical path difference between the optical path between the beam splitter assembly and the movable reflector and the optical path between the beam splitter assembly and the fixed reflector, and the surface of the light transmitting portion on the reflector device side is located on the same plane as the third surface of the optical functional component. Thus, for example, when the reference position when the movable reflector is reciprocated in the first direction is located on the third surface of the optical functional component, the optical path difference between the two optical paths can be corrected by reducing the difference between the optical path length of the optical path between the beam splitter assembly and the movable reflector (the optical path length taking into account the refractive index of each medium through which the optical path passes) and the optical path length of the optical path between the beam splitter assembly and the fixed reflector.

[0019] In the reflector assembly of one aspect of the present invention, the substrate may further have a sixth surface spaced apart from the optical functional component in a region including at least a portion of the outer edge of the substrate when viewed from the first direction. Thus, when the second surface of the substrate and the third surface of the optical functional component are bonded to each other, the reflector device can be operated by grasping the region of the substrate provided with the sixth surface.

[0020] In the reflector assembly of one aspect of the present invention, the outer edge of the optical functional component may be located outside the outer edge of the base when viewed from the first direction. Thus, a strong bond between the base of the reflector device and the optical functional component can be achieved. In addition, the outer edge of the base can be protected.

[0021] The reflector assembly of one aspect of the present invention may further include a stress relief substrate mounted on the fourth surface of the optical functional component via the fixed reflector. By placing the reflector assembly on the installation object via the stress relief substrate, for example, even if the installation object is deformed, its influence on the interference optical system can be suppressed.

[0022] An optical module according to one aspect of the present invention includes the above-mentioned reflector assembly and a beam splitter assembly that forms an interference optical system together with a movable reflector and a fixed reflector.

[0023] In this optical module, a high-precision interference optical system can be constructed using the above-mentioned mirror assembly.

[0024] Effects of the Invention

[0025] According to the present invention, it is possible to provide a mirror assembly suitable for compactly configuring a high-precision interference optical system and an optical module including such a mirror assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a cross-sectional view of an optical module according to one embodiment.

[0027] Figure 2 yes Figure 1 A top view of the reflector assembly is shown.

[0028] Figure 3 is along Figure 2 A cross-sectional view of the reflector assembly along line III-III is shown.

[0029] Figure 4 is along Figure 2 A cross-sectional view of the reflector assembly along line IV-IV is shown.

[0030] Figure 5 is along Figure 2 A schematic cross-sectional view of the mirror device along line VV is shown.

[0031] Figure 6 yes Figure 2 A partial enlarged view of the reflector device is shown.

[0032] Figure 7 yes Figure 2 A top view of the optical functional component shown.

[0033] Figure 8 is along Figure 1 A cross-sectional view of the optical module along line VIII-VIII is shown.

[0034] Fig. 9 is along Figure 1 A cross-sectional view of the optical module taken along line IX-IX is shown.

[0035] Fig.10 yes Figure 1 A schematic cross-sectional view of the mirror assembly and beam splitter assembly is shown.

[0036] Fig.11 is a cross-sectional view of a beam splitter assembly according to a modified example.

[0037] Fig.12 It is a schematic cross-sectional view of a reflector assembly according to a modified example.

[0038] Fig.13 It is a cross-sectional view of a reflector assembly according to a modified example.

[0039] Fig.14 It is a cross-sectional view of a reflector assembly according to a modified example.

[0040] Fig.15 1 is a top view of a reflector assembly of the embodiment.

[0041] Fig.16 It is a cross-sectional view for explaining the manufacturing process of the reflector assembly of the modification example.

[0042] Fig.17 It is a cross-sectional view for explaining the manufacturing process of the reflector assembly of the modification example.

[0043] Fig.18 It is a top view of a reflector device according to a modified example.

[0044] Fig.19 It is a top view of an optical functional component according to a modified example. DETAILED DESCRIPTION

[0045] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same reference numerals are given to the same or corresponding parts in each figure, and the overlapping parts are omitted.

[0046] [Structure of optical module]

[0047] like Figure 1 As shown, the optical module 1 includes a reflector assembly 2, a beam splitter assembly 3, a light incident portion 4, a first light detector 6, a second light source 7, a second light detector 8, a support body 9, a first support structure 11 and a second support structure 12. The reflector assembly 2 is arranged on one side of the support body 9 in the Z-axis direction (first direction), for example, mounted on the support body 9 by an adhesive. The support body 9 is formed of, for example, copper tungsten, for example, in the shape of a rectangular plate. The reflector assembly 2 includes a movable reflector 22 that moves along the Z-axis direction and a fixed reflector 16 whose position is fixed (details will be described later). In addition, the Z-axis direction is, for example, a vertical direction, and one side in the Z-axis direction is, for example, an upper side.

[0048] The beam splitter assembly 3 is arranged on one side in the Z-axis direction of the reflector assembly 2 and is supported by a first support structure 11. The first support structure 11 is mounted on the support body 9, for example, by an adhesive. The light incident portion 4 is arranged on one side in the X-axis direction (a second direction intersecting the first direction) of the beam splitter assembly 3 and is supported by a second support structure 12. The first photodetector 6, the second light source 7, and the second photodetector 8 are arranged on one side in the Z-axis direction of the beam splitter assembly 3 and are supported by the second support structure 12. The second support structure 12 is mounted on the support body 9, for example, by bolts.

[0049] In the optical module 1, the beam splitter assembly 3, the movable mirror 22 and the fixed mirror 16 constitute interference optical systems for the measuring light L0 and the laser light L10. The interference optical systems for the measuring light L0 and the laser light L10 are, for example, Michelson interference optical systems.

[0050] Regarding the measuring light L0, the interference light L1 of the measuring light is detected as follows. That is, when the measuring light L0 incident from the first light source (not shown) via the measuring object (not shown) or the measuring light L0 emitted from the measuring object (for example, the light emitted by the measuring object itself) is incident on the beam splitter assembly 3 from the light incident portion 4, the measuring light L0 is split into a part and a remaining part in the beam splitter assembly 3. Then, a part of the measuring light L0 is reflected by the movable reflector 22 that reciprocates in the Z-axis direction and returns to the beam splitter assembly 3. On the other hand, the remaining part of the measuring light L0 is reflected by the fixed reflector 16 and returns to the beam splitter assembly 3. The part of the measuring light L0 that has returned to the beam splitter assembly 3 and the remaining part are emitted from the beam splitter assembly 3 as the interference light L1, and the interference light L1 of the measuring light is detected by the first light detector 6.

[0051] For the laser light L10, the interference light L11 of the laser light is detected as follows. That is, when the laser light L10 emitted from the second light source 7 is incident on the beam splitter assembly 3, the laser light L10 is split into a part and a remaining part in the beam splitter assembly 3. Then, a part of the laser light L10 is reflected by the movable reflector 22 that reciprocates along the Z-axis direction and returns to the beam splitter assembly 3. On the other hand, the remaining part of the laser light L10 is reflected by the fixed reflector 16 and returns to the beam splitter assembly 3. The part and the remaining part of the laser light L10 that have returned to the beam splitter assembly 3 are emitted from the beam splitter assembly 3 as interference light L11, and the interference light L11 of the laser light is detected by the second light detector 8.

[0052] According to the optical module 1 , the position of the movable mirror 22 in the Z-axis direction can be calculated based on the detection result of the laser interference light L11 , and the measurement object can be spectrally analyzed based on the position measurement result and the detection result of the measurement light interference light L1 .

[0053] [Structure of the reflector assembly]

[0054] like Figure 2 , Figure 3 and Figure 4 As shown, the mirror assembly 2 includes a mirror device 20, an optical function component 13, a fixed mirror 16, and a stress relaxation substrate 17. The mirror device 20 includes a base 21, a movable mirror 22, and a drive unit 23.

[0055] The substrate 21 has a first surface 21a (a surface on one side in the Z-axis direction) and a second surface 21b on the opposite side to the first surface 21a. The first surface 21a and the second surface 21b are respectively the main surfaces of the substrate 21. The substrate 21 is, for example, in the shape of a rectangular plate, for example, having a size of about 10 mm×15 mm×0.35 mm (thickness). The movable reflector 22 has a reflector surface 22a and a movable portion 22b on which the reflector surface 22a is arranged. The movable reflector 22 is supported on the substrate 21 in a manner that allows it to move in the Z-axis direction perpendicular to the first surface 21a (the first direction intersecting the first surface). The drive unit 23 moves the movable reflector 22 in the Z-axis direction.

[0056] A pair of light passing portions 24 and 25 are formed in the reflector device 20. The pair of light passing portions 24 and 25 are arranged on both sides of the movable reflector 22 in the X-axis direction. The light passing portion (first light passing portion) 24 constitutes the first part of the optical path between the beam splitter assembly 3 and the fixed reflector 16. In addition, in the present embodiment, the light passing portion 25 does not function as a light passing portion.

[0057] Here, refer to Figure 2 , Figure 5 and Figure 6 The structure of the reflector device 20 is described in detail. Figure 5 yes Figure 3 The schematic cross-sectional view of the reflector device 20 is shown in FIG. Figure 5 , for example, the mirror device 20 is schematically shown in a state where the size in the Z-axis direction is enlarged compared to the actual size.

[0058] The base 21, the movable part 22b of the movable reflector 22 and the driving part 23 are composed of a SOI (Silicon On Insulator) substrate (semiconductor substrate) 100. That is, the reflector device 20 is composed of the SOI substrate 100. The reflector device 20 is formed in the shape of a rectangular plate, for example. The SOI substrate 100 has a support layer 101, a device layer 102 and an intermediate layer 103. The support layer 101 is a first silicon layer (first semiconductor layer). The device layer 102 is a second silicon layer (second semiconductor layer). The intermediate layer 103 is an insulating layer arranged between the support layer 101 and the device layer 102. The SOI substrate 100 has a support layer 101, an intermediate layer 103 and a device layer 102 in this order from one side in the Z-axis direction.

[0059] The substrate 21 is composed of a supporting layer 101, a device layer 102, and a portion of an intermediate layer 103. The first surface 21a of the substrate 21 is the surface of the supporting layer 101 on the opposite side to the intermediate layer 103. The second surface 21b of the substrate 21 is the surface of the device layer 102 on the opposite side to the intermediate layer 103. The supporting layer 101 constituting the substrate 21 is thicker than the device layer 102 constituting the substrate 21. The thickness of the supporting layer 101 constituting the substrate 21 is, for example, about 4 times the thickness of the device layer 102 constituting the substrate 21. In the reflector assembly 2, as described later, the second surface 21b of the substrate 21 and the third surface 13a of the optical functional component 13 are bonded to each other (see Figure 3 and Figure 4 ).

[0060] The movable reflector 22 is arranged with the intersection of the axis R1 and the axis R2 as the center position (center of gravity position). The axis R1 is a straight line extending in the X-axis direction. The axis R2 is a straight line extending in the Y-axis direction. When viewed from the Z-axis direction, the portion of the reflector device 20 other than the portion overlapping with the sixth surface 21d of the substrate 21 described later is a shape that is line-symmetrical with respect to the axis R1 and the axis R2.

[0061] The movable reflector 22 (movable part 22b) has a configuration part 221, a frame part 222, a pair of connecting parts 223 and a beam part 224. The configuration part 221, the frame part 222 and the pair of connecting parts 223 are composed of a part of the device layer 102. The configuration part 221 is circular when viewed from the Z-axis direction. The configuration part 221 has a central part 221a and an outer edge part 221b. On a surface 221as on one side of the central part 221a in the Z-axis direction, a reflector surface 22a is provided, for example, by forming a metal film (metal layer). The reflector surface 22a extends perpendicularly to the Z-axis direction and is circular. The surface 221as of the central part 221a is a surface on the intermediate layer 103 side of the device layer 102. The reflector surface 22a is located at a position closer to the other side in the Z-axis direction than the first surface 21a of the substrate 21. In other words, the first surface 21a is located at a position closer to one side in the Z-axis direction than the reflector surface 22a. The outer edge portion 221 b surrounds the central portion 221 a when viewed from the Z-axis direction.

[0062] The frame portion 222 extends in an annular shape so as to surround the configuration portion 221 at a predetermined interval when viewed from the Z-axis direction. The frame portion 222 is, for example, an annular shape when viewed from the Z-axis direction. A pair of connecting portions 223 connect the configuration portion 221 and the frame portion 222 to each other. The pair of connecting portions 223 are arranged on both sides of the configuration portion 221 in the Y-axis direction.

[0063] The beam portion 224 is composed of a support layer 101 and an intermediate layer 103 arranged on the device layer 102. The beam portion 224 has an inner beam portion 224a, an outer beam portion 224b, and a pair of connecting beam portions 224c. The inner beam portion 224a is arranged on the surface of one side of the outer edge portion 221b in the Z-axis direction. The inner beam portion 224a surrounds the reflector surface 22a when viewed from the Z-axis direction. For example, the outer edge of the inner beam portion 224a is spaced apart from the outer edge of the arrangement portion 221 at a predetermined interval when viewed from the Z-axis direction, and extends along the outer edge of the arrangement portion 221. The inner edge of the inner beam portion 224a is spaced apart from the outer edge of the reflector surface 22a at a predetermined interval when viewed from the Z-axis direction, and extends along the outer edge of the reflector surface 22a. The end surface 224as on one side of the inner beam portion 224a in the Z-axis direction is located at a position closer to the Z-axis side than the reflector surface 22a.

[0064] The outer beam portion 224b is arranged on the surface of one side in the Z-axis direction of the frame portion 222. The outer beam portion 224b surrounds the inner beam portion 224a and also surrounds the reflective mirror surface 22a when viewed from the Z-axis direction. For example, the outer edge of the outer beam portion 224b is spaced apart from the outer edge of the frame portion 222 at a predetermined interval when viewed from the Z-axis direction, and extends along the outer edge of the frame portion 222. The inner edge of the outer beam portion 224b is spaced apart from the inner edge of the frame portion 222 at a predetermined interval when viewed from the Z-axis direction, and extends along the inner edge of the frame portion 222. The end surface 224bs of the outer beam portion 224b on one side in the Z-axis direction is located on the Z-axis side of the reflective mirror surface 22a.

[0065] The pair of connecting beams 224c are respectively arranged on the surface of one side in the Z-axis direction of the pair of connecting parts 223. Each connecting beam 224c connects the inner beam 224a and the outer beam 224b to each other. The end surface 224cs on one side in the Z-axis direction of the connecting beam 224c is located at a position closer to the Z-axis direction than the reflective mirror surface 22a.

[0066] The thickness of the inner beam 224a, the outer beam 224b, and the connecting beams 224c in the Z-axis direction is equal to each other. That is, the thickness of the supporting layer 101 constituting the inner beam 224a, the outer beam 224b, and the connecting beams 224c is equal to each other. The end surface 224as of the inner beam 224a, the end surface 224bs of the outer beam 224b, and the end surface 224cs of the connecting beams 224c are located on the same plane perpendicular to the Z-axis direction. The supporting layer 101 constituting the inner beam 224a, the outer beam 224b, and the connecting beams 224c is thinner than the supporting layer 101 constituting the base 21. Therefore, the end surfaces 224as, 224bs, and 224cs are located on the one side of the first surface 21a of the base 21 in the Z-axis direction. In other words, the first surface 21 a is located on the other side in the Z-axis direction relative to the end surfaces 224as , 224bs , and 224cs .

[0067] When viewed from the Z-axis direction, the width of the outer beam portion 224b is wider than the width of the inner beam portion 224a. The width of the inner beam portion 224a when viewed from the Z-axis direction refers to the length of the inner beam portion 224a in the direction perpendicular to the extension direction of the inner beam portion 224a, and in the present embodiment, it is the length of the inner beam portion 224a in the radial direction of the inner beam portion 224a. This is also true for the width of the outer beam portion 224b when viewed from the Z-axis direction. The width of each connecting beam portion 224c is wider than the width of each inner beam portion 224a and the width of each outer beam portion 224b. The width of each connecting beam portion 224c is the length of each connecting beam portion 224c along the extension direction of the inner beam portion 224a.

[0068] The driving portion 23 includes a first elastic supporting portion 26 , a second elastic supporting portion 27 , and an actuator portion 28 . The first elastic supporting portion 26 , the second elastic supporting portion 27 , and the actuator portion 28 are formed by a part of the device layer 102 .

[0069] The first elastic support portion 26 and the second elastic support portion 27 are respectively connected between the base 21 and the movable mirror 22. The first elastic support portion 26 and the second elastic support portion 27 support the movable mirror 22 (movable portion 22b) so that the movable mirror 22 can move in the Z-axis direction.

[0070] The first elastic support portion 26 has a pair of levers 261, a first link member 262, a second link member 263, a pair of beam members 264, an intermediate member 265, a pair of first torsion bars (first torsion support portion) 266, a pair of second torsion bars (second torsion support portion) 267, a pair of nonlinear buffer springs 268 and a plurality of electrode support portions 269.

[0071] A pair of levers 261 are arranged on both sides of the light passing portion 24 in the Y-axis direction and are opposite to each other in the Y-axis direction. Each lever 261 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction. Each lever 261 has a first portion 261a, a second portion 261b arranged on the opposite side of the movable reflector 22 relative to the first portion 261a, and a third portion 261c connected to the first portion 261a and the second portion 261b. The first portion 261a and the second portion 261b extend in the X-axis direction. The length of the first portion 261a in the X-axis direction is shorter than the length of the second portion 261b in the X-axis direction. The third portion 261c of the pair of levers 261 extends obliquely in a manner that the further away from the movable reflector 22, the more separated from each other.

[0072] The first link member 262 is mounted between the first end portions 261d of the pair of levers 261 on the opposite side to the movable reflector 22. The first link member 262 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends in the Y-axis direction. The second link member 263 is mounted between the second end portions 261e of the pair of levers 261 on the movable reflector 22 side. The second link member 263 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends in the Y-axis direction. The width of the second link member 263 in the X-axis direction is narrower than the width of the first link member 262 in the X-axis direction. The length of the second link member 263 in the Y-axis direction is shorter than the length of the first link member 262 in the Y-axis direction.

[0073] A pair of beam members 264 are respectively arranged between the second portion 261b of the pair of levers 261 and the first connecting rod member 262. Each beam member 264 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction. The pair of beam members 264 extend obliquely in a manner that the farther away from the movable reflector 22, the closer they are to each other. The pair of levers 261, the first connecting rod member 262, the second connecting rod member 263 and the pair of beam members 264 define the light passing portion 24. The light passing portion 24 is polygonal when viewed from the Z-axis direction. The light passing portion 24 is, for example, a cavity (hole). Alternatively, a material having light transmittance to the measurement light L0 and the laser light L10 may be arranged in the light passing portion 24.

[0074] The intermediate member 265 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends along the Y-axis direction. The intermediate member 265 is disposed between the movable reflector 22 and the second link member 263 (in other words, between the movable reflector 22 and the light passing portion 24). The intermediate member 265 is connected to the movable reflector 22 via a nonlinear relaxation spring 268 as described later.

[0075] A pair of first torsion bars 266 are respectively arranged between the first end 261d of one lever 261 and the base 21 and between the first end 261d of the other lever 261 and the base 21. That is, a pair of first torsion bars 266 are respectively connected between a pair of levers 261 and the base 21. Each first torsion bar 266 extends along the Y-axis direction. A pair of first torsion bars 266 are arranged on the same center line parallel to the Y-axis direction. In the present embodiment, the center line of each first torsion bar 266 and the center line of the first connecting rod component 262 are located on the same straight line. A protrusion 261f protruding outward in the Y-axis direction is formed at the first end 261d of each lever 261, and each first torsion bar 266 is connected to the protrusion 261f.

[0076] The pair of second torsion bars 267 are respectively arranged between the second end 261e of one lever 261 and one end of the intermediate member 265 and between the second end 261e of the other lever 261 and the other end of the intermediate member 265. That is, the pair of second torsion bars 267 are respectively connected between the pair of levers 261 and the movable reflector 22. Each second torsion bar 267 extends in the Y-axis direction. The pair of second torsion bars 267 are arranged on the same center line parallel to the Y-axis direction.

[0077] A pair of nonlinear relaxation springs 268 are connected between the movable reflector 22 and the intermediate member 265. That is, a pair of nonlinear relaxation springs 268 are connected between the movable reflector 22 and the second torsion bar 267. Each nonlinear relaxation spring 268 has a meandering portion 268a extending in a meandering manner when viewed from the Z-axis direction. The meandering portion 268a includes a plurality of straight-line portions 268b extending in the Y-axis direction and arranged in the X-axis direction and a plurality of return portions 268c alternately connecting the two ends of the plurality of straight-line portions 268b. One end of the meandering portion 268a is connected to the intermediate member 265, and the other end of the meandering portion 268a is connected to the frame portion 222. The portion of the meandering portion 268a on the frame portion 222 side is shaped to be formed along the outer edge of the frame portion 222.

[0078] The nonlinear relaxation spring 268 is configured such that, in a state where the movable mirror 22 moves in the Z-axis direction, the amount of deformation of the nonlinear relaxation spring 268 around the Y-axis direction is smaller than the amount of deformation of each of the first torsion bar 266 and the second torsion bar 267 around the Y-axis direction, and the amount of deformation of the nonlinear relaxation spring 268 in the X-axis direction is larger than the amount of deformation of each of the first torsion bar 266 and the second torsion bar 267 in the X-axis direction. Thus, it is possible to suppress the occurrence of nonlinearity in the torsional deformation of the first torsion bar 266 and the second torsion bar 267, and to suppress the reduction in the control characteristics of the movable mirror 22 due to the nonlinearity. In addition, the amount of deformation of the first torsion bar 266, the second torsion bar 267, and the nonlinear relaxation spring 268 around the Y-axis direction refers to, for example, the absolute value of the torsion amount (torsion angle). The amount of deformation of the first torsion bar 266, the second torsion bar 267, and the nonlinear relaxation spring 268 in the X-axis direction refers to, for example, the absolute value of the deflection amount. The deformation amount of a certain component around the Y-axis direction refers to the deformation amount of the component in the circumferential direction of a circle centered on an axis passing through the center of the component and parallel to the Y-axis. This also applies to the first torsion bar 276, the second torsion bar 277, and the nonlinear relaxation spring 278 described later.

[0079] The plurality of electrode support parts 269 include a pair of first electrode support parts 269a, a pair of second electrode support parts 269b, and a pair of third electrode support parts 269c. Each electrode support part 269a, 269b, 269c is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends along the Y-axis direction. Each electrode support part 269a, 269b, 269c extends from the second portion 261b of the lever 261 to the opposite side of the light passing portion 24. A pair of first electrode support parts 269a is arranged on the same center line parallel to the Y-axis direction. A pair of second electrode support parts 269b is arranged on the same center line parallel to the Y-axis direction. A pair of third electrode support parts 269c is arranged on the same center line parallel to the Y-axis direction. In the X-axis direction, the first electrode support part 269a, the second electrode support part 269b, and the third electrode support part 269c are arranged in sequence from the movable reflector 22 side.

[0080] The second elastic support portion 27 has a pair of levers 271, a first link component 272, a second link component 273, a pair of beam components 274, an intermediate component 275, a pair of first torsion bars (first torsion support portion) 276, a pair of second torsion bars (second torsion support portion) 277, a pair of nonlinear buffer springs 278 and a plurality of electrode support portions 279.

[0081] A pair of levers 271 are arranged on both sides of the light passing portion 25 in the Y-axis direction and are opposite to each other in the Y-axis direction. Each lever 271 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction. Each lever 271 has a first portion 271a, a second portion 271b arranged on the opposite side of the first portion 271a from the movable reflector 22, and a third portion 271c connected to the first portion 271a and the second portion 271b. The first portion 271a and the second portion 271b extend in the X-axis direction. The length of the first portion 271a in the X-axis direction is shorter than the length of the second portion 271b in the X-axis direction. The third portion 271c of the pair of levers 271 extends obliquely in a manner that the further away from the movable reflector 22, the more separated from each other.

[0082] The first link member 272 is mounted between the first end portions 271d of the pair of levers 271 on the opposite side to the movable reflector 22. The first link member 272 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends in the Y-axis direction. The second link member 273 is mounted between the second end portions 271e of the pair of levers 271 on the movable reflector 22 side. The second link member 273 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends in the Y-axis direction. The width of the second link member 273 in the X-axis direction is narrower than the width of the first link member 272 in the X-axis direction. The length of the second link member 273 in the Y-axis direction is shorter than the length of the first link member 272 in the Y-axis direction.

[0083] A pair of beam members 274 are respectively arranged between the second portion 271b of the pair of levers 271 and the first connecting rod member 272. Each beam member 274 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction. The pair of beam members 274 extend obliquely in a manner that the farther away from the movable reflector 22, the closer they are to each other. The pair of levers 271, the first connecting rod member 272, the second connecting rod member 273 and the pair of beam members 274 define the light passing portion 25. The light passing portion 25 is polygonal when viewed from the Z-axis direction. The light passing portion 25 is, for example, a cavity (hole). Alternatively, a material having light transmittance to the measuring light L0 and the laser light L10 may also be arranged in the light passing portion 25.

[0084] The intermediate member 275 is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends along the Y-axis direction. The intermediate member 275 is disposed between the movable reflector 22 and the second link member 273 (in other words, between the movable reflector 22 and the light passing portion 25). The intermediate member 275 is connected to the movable reflector 22 via a nonlinear relaxation spring 278 as described later.

[0085] A pair of first torsion bars 276 are respectively arranged between the first end 271d of one lever 271 and the base 21 and between the first end 271d of the other lever 271 and the base 21. That is, a pair of first torsion bars 276 are respectively connected between a pair of levers 271 and the base 21. Each first torsion bar 276 extends along the Y-axis direction. A pair of first torsion bars 276 are arranged on the same center line parallel to the Y-axis direction. In the present embodiment, the center line of each first torsion bar 276 and the center line of the first connecting rod component 272 are located on the same straight line. A protrusion 271f protruding outward in the Y-axis direction is formed at the first end 271d of each lever 271, and each first torsion bar 276 is connected to the protrusion 271f.

[0086] The pair of second torsion bars 277 are respectively arranged between the second end 271e of one lever 271 and one end of the intermediate member 275 and between the second end 271e of the other lever 271 and the other end of the intermediate member 275. That is, the pair of second torsion bars 277 are respectively connected between the pair of levers 271 and the movable reflector 22. Each second torsion bar 277 extends in the Y-axis direction. The pair of second torsion bars 277 are arranged on the same center line parallel to the Y-axis direction.

[0087] A pair of nonlinear easing springs 278 are connected between the movable reflector 22 and the intermediate member 275. That is, a pair of nonlinear easing springs 278 are connected between the movable reflector 22 and the second torsion bar 277. Each nonlinear easing spring 278 has a meandering portion 278a extending in a meandering manner when viewed from the Z-axis direction. The meandering portion 278a includes a plurality of straight-line portions 278b extending in the Y-axis direction and arranged in the X-axis direction, and a plurality of return portions 278c alternately connecting both ends of the plurality of straight-line portions 278b. One end of the meandering portion 278a is connected to the intermediate member 275, and the other end of the meandering portion 278a is connected to the frame portion 222. The portion of the meandering portion 278a on the frame portion 222 side is in a shape formed along the outer edge of the frame portion 222.

[0088] The nonlinear relaxation spring 278 is configured such that, when the movable mirror 22 moves in the Z-axis direction, the amount of deformation of the nonlinear relaxation spring 278 about the Y-axis direction is smaller than the amount of deformation of each of the first torsion bar 276 and the second torsion bar 277 about the Y-axis direction, and the amount of deformation of the nonlinear relaxation spring 278 about the X-axis direction is larger than the amount of deformation of each of the first torsion bar 276 and the second torsion bar 277 about the X-axis direction. Thus, it is possible to suppress the occurrence of nonlinearity in the torsional deformation of the first torsion bar 276 and the second torsion bar 277, and to suppress the deterioration of the control characteristics of the movable mirror 22 caused by the nonlinearity.

[0089] The plurality of electrode support parts 279 include a pair of first electrode support parts 279a, a pair of second electrode support parts 279b, and a pair of third electrode support parts 279c. Each electrode support part 279a, 279b, 279c is in the shape of a plate extending along a plane perpendicular to the Z-axis direction, and extends along the Y-axis direction. Each electrode support part 279a, 279b, 279c extends from the second portion 271b of the lever 271 to the opposite side of the light passing portion 25. A pair of first electrode support parts 279a is arranged on the same center line parallel to the Y-axis direction. A pair of second electrode support parts 279b is arranged on the same center line parallel to the Y-axis direction. A pair of third electrode support parts 279c is arranged on the same center line parallel to the Y-axis direction. In the X-axis direction, the first electrode support part 279a, the second electrode support part 279b, and the third electrode support part 279c are arranged in sequence from the movable reflector 22 side.

[0090] The actuator unit 28 moves the movable mirror 22 in the Z-axis direction. The actuator unit 28 includes a fixed comb electrode 281, a movable comb electrode 282, a fixed comb electrode 283, and a movable comb electrode 284. The positions of the fixed comb electrodes 281 and 283 are fixed. The movable comb electrodes 282 and 284 move with the movement of the movable mirror 22.

[0091] The fixed comb-teeth electrode 281 is provided on a portion of the surface of the device layer 102 of the substrate 21 that faces the electrode support portion 269. The fixed comb-teeth electrode 281 has a plurality of fixed comb teeth 281a extending along a plane perpendicular to the Y-axis direction. These fixed comb teeth 281a are arranged at predetermined intervals in the Y-axis direction.

[0092] The movable comb-teeth electrode 282 is provided on the surface of each first electrode support portion 269a on the movable reflector 22 side, the surfaces of each second electrode support portion 269b on both sides in the X-axis direction, and the surface of each third electrode support portion 269c on the movable reflector 22 side. The movable comb-teeth electrode 282 has a plurality of movable comb teeth 282a extending along a plane perpendicular to the Y-axis direction. These movable comb teeth 282a are arranged at predetermined intervals in the Y-axis direction.

[0093] In the fixed comb-teeth electrode 281 and the movable comb-teeth electrode 282, a plurality of fixed comb teeth 281a and a plurality of movable comb teeth 282a are arranged alternately. That is, each fixed comb tooth 281a of the fixed comb-teeth electrode 281 is located between the movable comb teeth 282a of the movable comb-teeth electrode 282. Adjacent fixed comb teeth 281a and movable comb teeth 282a are opposite to each other in the Y-axis direction. The distance between adjacent fixed comb teeth 281a and movable comb teeth 282a is, for example, about several μm.

[0094] The fixed comb-teeth electrode 283 is provided on a portion of the surface of the device layer 102 of the substrate 21 that faces the electrode support portion 279. The fixed comb-teeth electrode 283 has a plurality of fixed comb teeth 283a extending along a plane perpendicular to the Y-axis direction. These fixed comb teeth 283a are arranged at predetermined intervals in the Y-axis direction.

[0095] The movable comb-tooth electrode 284 is provided on the surface of each first electrode support portion 279a on the movable reflector 22 side, the surface of each second electrode support portion 279b on both sides in the X-axis direction, and the surface of each third electrode support portion 279c on the movable reflector 22 side. The movable comb-tooth electrode 284 has a plurality of movable comb teeth 284a extending along a plane perpendicular to the Y-axis direction. These movable comb teeth 284a are arranged at predetermined intervals in the Y-axis direction.

[0096] In the fixed comb-teeth electrode 283 and the movable comb-teeth electrode 284, a plurality of fixed comb teeth 283a and a plurality of movable comb teeth 284a are arranged alternately. That is, each fixed comb tooth 283a of the fixed comb-teeth electrode 283 is located between the movable comb teeth 284a of the movable comb-teeth electrode 284. Adjacent fixed comb teeth 283a and movable comb teeth 284a are opposite to each other in the Y-axis direction. The distance between adjacent fixed comb teeth 283a and movable comb teeth 284a is, for example, about several μm.

[0097] A plurality of electrode pads 211 are provided on the substrate 21. Each electrode pad 211 is arranged on the surface of the device layer 102 in an opening 213 formed on the first surface 21a of the substrate 21 in such a manner as to reach the device layer 102. Some of the plurality of electrode pads 211 are electrically connected to the fixed comb-tooth electrode 281 or the fixed comb-tooth electrode 283 via the device layer 102. Other electrode pads of the plurality of electrode pads 211 are electrically connected to the movable comb-tooth electrode 282 or the movable comb-tooth electrode 284 via the first elastic support portion 26 or the second elastic support portion 27. In addition, a pair of electrode pads 212 used as ground electrodes are provided on the substrate 21. The pair of electrode pads 212 are arranged on the first surface 21a in such a manner as to be located on both sides of the movable reflector 22 in the Y-axis direction.

[0098] In the reflector device 20 constructed as described above, an electrical signal for moving the movable reflector 22 in the Z-axis direction is input to the drive unit 23 via the lead pin 113 and the wire (not shown) described later. As a result, an electrostatic force is generated, for example, between the fixed comb-tooth electrode 281 and the movable comb-tooth electrode 282 facing each other and between the fixed comb-tooth electrode 283 and the movable comb-tooth electrode 284 facing each other, so that the movable reflector 22 moves to one side in the Z-axis direction. At this time, in the first elastic support part 26 and the second elastic support part 27, the first torsion bars 266, 276 and the second torsion bars 267, 277 are twisted, and elastic force is generated in the first elastic support part 26 and the second elastic support part 27. In the reflector device 20, by supplying a periodic electrical signal to the drive unit 23, the movable reflector 22 can be reciprocated horizontally in the Z-axis direction at its resonant frequency. In this way, the drive unit 23 functions as an electrostatic actuator.

[0099] like Figure 2 , Figure 3 , Figure 4 and Figure 7 As shown, the optical functional component 13 has a third surface 13a (a surface on one side in the Z-axis direction) opposite to the second surface 21b of the substrate 21 and a fourth surface 13b on the opposite side to the third surface 13a. When viewed from the Z-axis direction, the outer edge 13c of the optical functional component 13 is located outside the outer edge 21c of the substrate 21. That is, when viewed from the Z-axis direction, the outer edge 13c of the optical functional component 13 surrounds the outer edge 21c of the substrate 21. The optical functional component 13 is integrally formed of a material that is transmissive to the measurement light L0 and the laser light L10. The optical functional component 13 is formed of, for example, glass in a rectangular plate shape, for example, having a size of about 15 mm×20 mm×4 mm (thickness). In addition, the material of the optical functional component 13 is selected, for example, according to the sensitivity wavelength of the optical module 1, and is glass when the sensitivity wavelength of the optical module 1 is in the near-infrared region, and is silicon when the sensitivity wavelength of the optical module 1 is in the mid-infrared region.

[0100] A pair of light-transmitting parts 14 and 15 are formed in the optical functional component 13. The light-transmitting part 14 is a part of the optical functional component 13 that is opposite to the light-transmitting part 24 of the reflector device 20 in the Z-axis direction. The light-transmitting part 15 is a part of the optical functional component 13 that is opposite to the light-transmitting part 25 of the reflector device 20 in the Z-axis direction. The surface 14a of the light-transmitting part 14 on the side of the reflector device 20 and the surface 15a of the light-transmitting part 15 on the side of the reflector device 20 are located on the same plane as the third surface 13a. The light-transmitting part (second light-transmitting part) 14 constitutes the second part (a part) of the optical path between the beam splitter assembly 3 and the fixed reflector 16. The light-transmitting part 14 is a part that corrects the optical path difference generated between the optical path between the beam splitter assembly 3 and the movable reflector 22 and the optical path between the beam splitter assembly 3 and the fixed reflector 16. In addition, in the present embodiment, the light-transmitting part 15 does not function as a light-transmitting part.

[0101] The optical functional component 13 has a fifth surface 13d that is opposite to the movable reflector 22 and the drive unit 23 of the reflector device 20. The fifth surface 13d is located closer to the fourth surface 13b than the third surface 13a. The fifth surface 13d extends to the outer edge 13c of the optical functional component 13 when viewed from the Z-axis direction. In the present embodiment, the fifth surface 13d surrounds the end of each light-transmitting portion 14, 15 on the reflector device 20 side, and extends to a pair of opposite sides extending along the Y-axis direction (a direction intersecting the first direction and the second direction) in the outer edge 13c of the optical functional component 13.

[0102] The third surface 13a of the optical functional component 13 is bonded to the second surface 21b of the substrate 21 by direct bonding (e.g., plasma activation bonding, surface-activated room-temperature bonding (SAB), atomic diffusion bonding (ADB), anodic bonding, fusion bonding, hydrophilic bonding, etc.). In the present embodiment, the third surface 13a extends on both sides of the fifth surface 13d in the Y-axis direction so as to face the plurality of electrode pads 211 and 212 provided on the substrate 21. Here, the fifth surface 13d is located closer to the fourth surface 13b than the third surface 13a, so that the fifth surface 13d is separated from the mirror device 20 in the region facing the movable mirror 22 and the drive unit 23. In addition, the surface 14a of the light-transmitting portion 14 and the surface 15a of the light-transmitting portion 15 are respectively opposite to the light-passing portions 24 and 25 of the reflector device 20. Thus, in the reflector assembly 2, it is possible to prevent the movable reflector 22 and the drive unit 23 from contacting the optical functional component 13 when the movable reflector 22 reciprocates in the Z-axis direction.

[0103] In addition, the substrate 21 of the reflector device 20 is formed with a sixth surface 21d spaced apart from the optical functional component 13 in a state where the third surface 13a of the optical functional component 13 and the second surface 21b of the substrate 21 are bonded to each other. The sixth surface 21d is spaced apart from the optical functional component 13 in a region including at least a portion of the outer edge of the substrate 21 when viewed from the Z-axis direction. In the present embodiment, the sixth surface 21d is formed by removing the device layer 102 and the intermediate layer 103 by etching along one side extending in the Y-axis direction of the outer edge of the substrate 21. In addition, a plurality of reference holes 13e are formed on the third surface 13a of the optical functional component 13. In the present embodiment, the plurality of reference holes 13e are formed on the third surface 13a in a manner corresponding to the plurality of corners of the substrate 21. When the third surface 13a of the optical functional component 13 and the second surface 21b of the base 21 are joined to each other, the operation of the reflector device 20 is implemented by grasping the portion of the base 21 corresponding to the sixth surface 21d, and the position of the reflector device 20 in the X-axis direction and the Y-axis direction and the angle of the reflector device 20 in the plane perpendicular to the Z-axis direction are adjusted based on the multiple reference holes 13e formed on the third surface 13a.

[0104] like Figure 3 and Figure 4As shown, the fixed reflector 16 is arranged on the opposite side of the reflector device 20 relative to the optical functional component 13, and its position relative to the base 21 of the reflector device 20 is fixed. The fixed reflector 16 is formed on the fourth surface 13b of the optical functional component 13 by vapor deposition, for example. The fixed reflector 16 has a reflector surface 16a perpendicular to the Z-axis direction. In the present embodiment, the reflector surface 22a of the movable reflector 22 and the reflector surface 16a of the fixed reflector 16 face one side in the Z-axis direction (the beam splitter assembly 3 side). In addition, the fixed reflector 16 is formed continuously with the fourth surface 13b of the optical functional component 13 in a manner that reflects the light transmitted from each light transmitting portion 14, 15 of the optical functional component 13, but a fixed reflector that reflects the light transmitted from the light transmitting portion 14 and a fixed reflector that reflects the light transmitted from the light transmitting portion 15 may be separately provided.

[0105] The stress relaxation substrate 17 is mounted on the fourth surface 13b of the optical functional component 13 via the fixed reflector 16. The stress relaxation substrate 17 is mounted on the fixed reflector 16 by, for example, an adhesive. When viewed from the Z-axis direction, the outer edge of the stress relaxation substrate 17 is located outside the outer edge 13c of the optical functional component 13. That is, when viewed from the Z-axis direction, the outer edge of the stress relaxation substrate 17 surrounds the outer edge 13c of the optical functional component 13. The thermal expansion coefficient of the stress relaxation substrate 17 is closer to the thermal expansion coefficient of the base 21 of the reflector device 20 (more specifically, the thermal expansion coefficient of the support layer 101) than the thermal expansion coefficient of the optical functional component 13. In addition, the thickness of the stress relaxation substrate 17 is closer to the thickness of the base 21 of the reflector device 20 than the thickness of the optical functional component 13. The stress relaxation substrate 17 is formed into a rectangular plate shape using, for example, silicon, and has a size of, for example, about 16 mm×21 mm×0.65 mm (thickness).

[0106] In the reflector assembly 2 constructed as described above, Figure 1 As shown, the surface of the stress relaxation substrate 17 opposite to the optical functional component 13 is fixed to the surface 9a (the surface on one side in the Z-axis direction) of the support body 9 by, for example, an adhesive, and thus mounted on the support body 9. When the reflector assembly 2 is mounted on the support body 9, as shown in FIG. Figure 8 As shown in FIG. 1 , the position of the reflector device 20 in the X-axis direction and the Y-axis direction and the angle of the reflector device 20 in the plane perpendicular to the Z-axis direction are adjusted based on the reference hole 9b formed in the support body 9. Figure 8 The second support structure 12 is omitted in the figure.

[0107] [Structure of the first support structure and beam splitter assembly]

[0108] like Figure 1 and Figure 8As shown, the first support structure 11 includes a frame 111, a light-transmitting member 112, and a plurality of lead pins 113. The frame 111 is formed so as to surround the reflector assembly 2 when viewed from the Z-axis direction, and is mounted on the surface 9a of the support body 9 by, for example, an adhesive such as silver solder. The frame 111 is formed of, for example, ceramic, and is, for example, in a rectangular frame shape. An end face 111a of the frame 111 on the opposite side to the support body 9 is located on the opposite side to the support body 9 compared to the first surface 21a of the base 21 of the reflector device 20.

[0109] The light-transmitting member 112 is formed in a manner to close the opening of the frame 111, and is mounted on the end surface 111a of the frame 111 by, for example, an adhesive. The light-transmitting member 112 is formed of a material that is transmissive to the measuring light L0 and the laser light L10, and is, for example, in the shape of a rectangular plate. Here, the end surface 111a of the frame 111 is located on the opposite side of the support body 9 compared to the first surface 21a of the base 21 of the reflector device 20, so that the light-transmitting member 112 is separated from the reflector device 20. As a result, the optical module 1 prevents the movable reflector 22 and the drive unit 23 from contacting the light-transmitting member 112 when the movable reflector 22 reciprocates in the Z-axis direction. In addition, in the optical module 1, the support body 9, the frame 111, and the light-transmitting member 112 constitute a package that accommodates the reflector assembly 2.

[0110] Each lead pin 113 is provided in the frame 111 in such a manner that one end 113a is located inside the frame 111 and the other end (not shown) is located outside the frame 111. One end 113a of the lead pin 113 is electrically connected to the electrode pads 211 and 212 corresponding to the lead pin 113 in the reflector device 20 via a wire (not shown). In the optical module 1, an electrical signal for moving the movable reflector 22 in the Z-axis direction is input to the drive unit 23 through a plurality of lead pins 113. In the present embodiment, a step surface 111b extending in the X-axis direction on both sides of the optical functional component 13 in the Y-axis direction is formed in the frame 111, and one end 113a of each lead pin 113 is arranged on the step surface 111b. Each lead pin 113 extends in the Z-axis direction on both sides of the support body 9 in the Y-axis direction, and the other end of each lead pin 113 is located on the other side of the support body 9 in the Z-axis direction.

[0111] like Fig.10 As shown, the beam splitter assembly 3 is mounted on the surface 112a of the light-transmitting component 112 on the opposite side of the reflector device 20, for example, by an optical adhesive that also serves as a refractive index matching agent. The beam splitter assembly 3 has a first reflector surface 31, a second reflector surface 32, and a plurality of optical surfaces 33a, 33b, 33c, and 33d. The beam splitter assembly 3 is formed by joining a plurality of optical blocks 34 and 35. Each optical block 34 and 35 is formed of a material having a refractive index that is the same as or similar to that of the optical functional component 13. In addition, Fig.10 yes Figure 1 The schematic cross-sectional view of the reflector assembly 2 and the beam splitter assembly 3 is shown in FIG. Fig.10 In the figure, for example, the reflector device 20 is schematically shown in a state where the size in the Z-axis direction is enlarged to be larger than the actual size.

[0112] The first reflector surface 31 is a reflector surface (for example, a half-reflector surface) inclined with respect to the Z-axis direction, and is formed between the optical block 34 and the optical block 35. In the present embodiment, the first reflector surface 31 is a surface parallel to the Y-axis direction and is a surface that forms an angle of 45° with the Z-axis direction, and is a surface that is inclined in a manner that the closer it is to the reflector device 20, the farther it is from the light incident portion 4. The first reflector surface 31 has a function of reflecting a portion of the measurement light L0 and transmitting the remaining portion of the measurement light L0, and a function of reflecting a portion of the laser light L10 and transmitting the remaining portion of the laser light L10. The first reflector surface 31 is formed, for example, of a dielectric multilayer film. The first reflector surface 31 overlaps with the light passing portion 24 of the reflector device 20, the light transmitting portion 14 of the optical functional component 13, and the reflector surface 16a of the fixed reflector 16 when viewed from the Z-axis direction, and overlaps with the light incident portion 4 when viewed from the X-axis direction (see Figure 1 ) That is, the first reflecting mirror surface 31 is opposite to the fixed reflecting mirror 16 in the Z-axis direction, and is opposite to the light incident portion 4 in the X-axis direction.

[0113] The second reflector surface 32 is a reflector surface (e.g., a total reflection reflector surface) parallel to the first reflector surface 31, and is formed on the optical block 35 in a manner that is located on the opposite side of the light incident portion 4 relative to the first reflector surface 31. The second reflector surface 32 has a function of reflecting the measurement light L0 and a function of reflecting the laser light L10. The second reflector surface 32 is formed of, for example, a metal film. The second reflector surface 32 overlaps with the reflector surface 22a of the movable reflector 22 of the reflector device 20 when viewed from the Z-axis direction, and overlaps with the first reflector surface 31 when viewed from the X-axis direction. That is, the second reflector surface 32 is opposite to the movable reflector 22 in the Z-axis direction, and is opposite to the first reflector surface 31 in the X-axis direction.

[0114] The optical surface 33a is a surface perpendicular to the Z-axis direction, and is formed in the optical block 35 so as to be located on the opposite side of the reflector device 20 relative to the first reflector surface 31. The optical surface 33b is a surface perpendicular to the Z-axis direction, and is formed in the optical block 35 so as to be located on the reflector device 20 side relative to the second reflector surface 32. The optical surface 33c is a surface perpendicular to the Z-axis direction, and is formed in the optical block 34 so as to be located on the reflector device 20 side relative to the first reflector surface 31. The optical surface 33b and the optical surface 33c are located on the same plane. The optical surface 33d is a surface perpendicular to the X-axis direction, and is formed in the optical block 34 so as to be located on the light incident portion 4 side relative to the first reflector surface 31. Each of the optical surfaces 33a, 33b, 33c, and 33d has a function of transmitting the measurement light L0 and a function of transmitting the laser light L10.

[0115] The beam splitter assembly 3 constructed as described above is mounted on the light-transmitting member 112 by fixing the optical surface 33b and the optical surface 33c located on the same plane to the surface 112a of the light-transmitting member 112 using, for example, an optical adhesive. Fig. 9 As shown in FIG. 1 , the position of the beam splitter assembly 3 in the X-axis direction and the Y-axis direction and the angle of the beam splitter assembly 3 in the plane perpendicular to the Z-axis direction are adjusted based on the reference hole 9b formed in the support body 9. Fig. 9 The second support structure 12 is omitted in the figure.

[0116] Here, refer to Fig.10 The optical path of the measuring light L0 and the optical path of the laser light L10 of the mirror assembly 2 and the beam splitter assembly 3 will be described in detail.

[0117] like Fig.10As shown, when the measurement light L0 enters the beam splitter assembly 3 along the X-axis direction through the optical surface 33d, a portion of the measurement light L0 transmits the first reflective mirror surface 31, is reflected by the second reflective mirror surface 32, passes through the optical surface 33b and the light-transmitting component 112, and reaches the reflective mirror surface 22a of the movable reflector 22. A portion of the measurement light L0 is reflected by the reflective mirror surface 22a of the movable reflector 22, travels in the opposite direction on the same optical path P1, and is reflected by the first reflective mirror surface 31. The remaining portion of the measurement light L0 is reflected by the first reflective mirror surface 31, passes through the optical surface 33c, the light-transmitting component 112, the light-transmitting portion 24 of the reflector device 20, and the light-transmitting portion 14 of the optical functional component 13, and reaches the reflective mirror surface 16a of the fixed reflector 16. The remaining portion of the measurement light L0 is reflected by the reflective mirror surface 16a of the fixed reflector 16, travels in the opposite direction on the same optical path P2, and is transmitted from the first reflective mirror surface 31. Part of the measuring light L0 reflected by the first reflecting mirror 31 and the remaining part of the measuring light L0 transmitted through the first reflecting mirror 31 become interference light L1, and the interference light L1 of the measuring light passes through the optical surface 33a and is emitted from the beam splitter unit 3 in the Z-axis direction.

[0118] On the other hand, when the laser light L10 enters the beam splitter assembly 3 along the Z-axis direction through the optical surface 33a, a portion of the laser light L10 is reflected by the first reflecting mirror surface 31 and the second reflecting surface 32, passes through the optical surface 33b and the light-transmitting member 112, and reaches the reflecting mirror surface 22a of the movable reflecting mirror 22. A portion of the laser light L10 is reflected by the reflecting mirror surface 22a of the movable reflecting mirror 22, travels in the reverse direction on the same optical path P3, and is reflected by the first reflecting mirror surface 31. The remaining portion of the laser light L10 passes through the first reflecting mirror surface 31, passes through the optical surface 33c, the light-transmitting member 112, the light-transmitting portion 24 of the reflecting mirror device 20, and the light-transmitting portion 14 of the optical functional component 13, and reaches the reflecting mirror surface 16a of the fixed reflecting mirror 16. The remaining portion of the laser light L10 is reflected by the reflecting mirror surface 16a of the fixed reflecting mirror 16, travels in the reverse direction on the same optical path P4, and passes through the first reflecting mirror surface 31. Part of the laser light L10 reflected by the first reflecting mirror 31 and the remaining part of the laser light L10 transmitted through the first reflecting mirror 31 become interference light L11, and the interference light L11 of the laser light passes through the optical surface 33a and is emitted from the beam splitter unit 3 in the Z-axis direction.

[0119] As described above, the light passing portion 24 of the reflector device 20 constitutes the first portion P2a of the optical path P2 of the measuring light L0 and the first portion P4a of the optical path P4 of the laser light L10 in the optical path between the beam splitter assembly 3 and the fixed reflector 16. In addition, the light transmitting portion 14 of the optical functional component 13 constitutes the second portion P2b of the optical path P2 of the measuring light L0 and the second portion P4b of the optical path P4 of the laser light L10 in the optical path between the beam splitter assembly 3 and the fixed reflector 16.

[0120] By forming the second portion P2b of the optical path P2 of the measuring light L0 with the light transmitting portion 14, the optical path difference between the two optical paths P1 and P2 can be corrected, so that the difference between the optical path length of the optical path P1 of the measuring light L0 (the optical path length taking into account the refractive index of each medium through which the optical path passes) and the optical path length of the optical path P2 of the measuring light L0 becomes smaller. Similarly, by forming the second portion P4b of the optical path P4 of the laser light L10 with the light transmitting portion 14, the optical path difference between the two optical paths P3 and P4 can be corrected, so that the difference between the optical path length of the optical path P3 of the laser light L10 and the optical path length of the optical path P4 of the laser light L10 becomes smaller. In this embodiment, the refractive index of the light-transmitting portion 14 is equal to the refractive index of each optical block constituting the beam splitter assembly 3, and the distance between the first reflecting mirror surface 31 and the second reflecting mirror surface 32 along the X-axis direction is equal to the thickness of the light-transmitting portion 14 along the Z-axis direction (that is, the distance between the surface 14a of the light-transmitting portion 14 along the Z-axis direction and the fourth surface 13b of the optical functional component 13).

[0121] [Structure of the Second Support Structure and the Light Incident Section, etc.]

[0122] like Figure 1 As shown, the second support structure 12 has a connecting unit 120. The connecting unit 120 includes a main body 121, a frame 122 and a fixing plate 123. The main body 121 includes a pair of side wall portions 124, 125 and a top wall portion 126. The pair of side wall portions 124, 125 are opposite to each other in the X-axis direction. An opening 124a is formed on one side of the side wall portion 124 in the X-axis direction. The top wall portion 126 is opposite to the support body 9 in the Z-axis direction. An opening 126a is formed in the top wall portion 126. The main body 121 is formed integrally with, for example, metal. A plurality of positioning pins 121a are formed in the main body 121. The main body 121 is positioned relative to the support body 9 by respectively embedding the positioning pins 121a into the reference holes 9b and holes 9c formed in the support body 9, and in this state, is mounted on the support body 9, for example, by bolts.

[0123] The frame 122 is arranged on the surface of the side wall 124 on the opposite side to the beam splitter assembly 3. The opening of the frame 122 is opposite to the beam splitter assembly 3 via the opening 124a of the side wall 124. The light incident portion 4 is arranged in the frame 122. The fixing plate 123 is a member for fixing the light incident portion 4 arranged in the frame 122 to the main body 121 (details will be described later).

[0124] The second support structure 12 further includes a holding unit 130. The holding unit 130 includes a main body 131, a frame 132, and a fixing plate 133. The main body 131 is mounted on the surface of the top wall 126 on the opposite side to the support body 9. The main body 131 is positioned relative to the main body 121 of the connecting unit 120 by a plurality of positioning pins 131a, and in this state, is mounted on the top wall 126 by, for example, bolts. A recess 134 is formed on the surface of the main body 131 on the opposite side to the support body 9. A first light passage hole 135, a second light passage hole 136, and a third light passage hole 137 are formed on the bottom surface of the recess 134. The first light passage hole 135 is formed at a position opposite to the first reflection mirror surface 31 of the beam splitter assembly 3 in the Z-axis direction. The second light passage hole 136 is formed on the other side of the first light passage hole 135 in the X-axis direction (i.e., on the opposite side to the light incident portion 4). The third light transmission hole 137 is formed on the other side of the second light transmission hole 136 in the X-axis direction.

[0125] The frame 132 is arranged on the bottom surface of the recess 134. The opening of the frame 132 is opposite to the third light passage hole 137. The second light source 7 is arranged in the frame 132. The first light detector 6 is arranged on the bottom surface of the recess 134 in a state opposite to the first light passage hole 135. The second light detector 8 is arranged on the bottom surface of the recess 134 in a state opposite to the second light passage hole 136. The fixing plate 133 is a component for fixing the first light detector 6 and the second light detector 8 arranged on the bottom surface of the recess 134 and the second light source 7 arranged in the frame 132 to the main body 131 (details will be described later).

[0126] The light incident portion 4 includes a holding member 41 and a collimating lens 42. The holding member 41 holds the collimating lens 42 and is configured to be connected to an optical fiber (not shown) that guides the measurement light L0. The collimating lens 42 collimates the measurement light L0 emitted from the optical fiber. When the optical fiber is connected to the holding member 41, the optical axis of the optical fiber coincides with the optical axis of the collimating lens 42.

[0127] A flange portion 41a is formed on the holding member 41. The flange portion 41a is disposed between the frame 122 and the fixing plate 123. In this state, by attaching the fixing plate 123 to the side wall portion 124, for example, by bolts, the light incident portion 4 disposed in the frame 122 is fixed to the main body 121. In this way, the light incident portion 4 is disposed on one side of the beam splitter assembly 3 in the X-axis direction and is supported by the second support structure 12. The light incident portion 4 allows the measurement light L0 incident from the first light source through the measurement object or the measurement light L0 emitted from the measurement object (in this embodiment, the measurement light L0 guided by the optical fiber) to enter the beam splitter assembly 3.

[0128] The optical filter 54 is installed in the frame 122. The optical filter 54 has the function of cutting off the laser L10. The optical filter 54 is arranged in the opening 124a of the side wall portion 124 in a state of being inclined relative to the optical axis of the light incident portion 4. The optical filter 54 closes the opening of the frame 122 when viewed from the X-axis direction. In this way, the optical filter 54 is arranged between the light incident portion 4 and the beam splitter assembly 3, and is supported by the second support structure 12 in a state of being inclined relative to the optical axis of the light incident portion 4. In the present embodiment, the optical surface of the optical filter 54 is a surface parallel to the Z-axis direction, and is a surface that forms an angle of 10° to 20° with the Y-axis direction. In addition, the optical axis of the light incident portion 4 is parallel to the X-axis direction.

[0129] The first photodetector 6 includes a holding member 61, a photodetection element 62, and a condenser lens 63. The holding member 61 holds the photodetection element 62 and the condenser lens 63. The photodetection element 62 detects interference light L1 of the measurement light. The photodetection element 62 is, for example, an InGaAs photodiode. The condenser lens 63 condenses the interference light L1 of the measurement light incident on the photodetection element 62 to the photodetection element 62. In the holding member 61, the optical axis of the photodetection element 62 and the optical axis of the condenser lens 63 coincide with each other.

[0130] A flange portion 61a is formed on the holding member 61. The flange portion 61a is disposed between the bottom surface of the recessed portion 134 of the main body 131 and the fixing plate 133. In this state, the fixing plate 133 is mounted on the main body 131 by, for example, bolts, and the first light detector 6 disposed on the bottom surface of the recessed portion 134 is fixed to the main body 131. In this way, the first light detector 6 is disposed on one side of the beam splitter assembly 3 in the Z-axis direction and is supported by the second support structure 12. The first light detector 6 is opposite to the first reflection mirror surface 31 of the beam splitter assembly 3 in the Z-axis direction. The first light detector 6 detects the interference light L1 of the measurement light emitted from the beam splitter assembly 3.

[0131] The second photodetector 8 includes a holding member 81, a photodetection element 82, and a condenser lens 83. The holding member 81 holds the photodetection element 82 and the condenser lens 83. The photodetection element 82 detects the interference light L11 of the laser. The photodetection element 82 is, for example, a Si photodiode. The condenser lens 83 condenses the interference light L11 of the laser incident on the photodetection element 82 to the photodetection element 82. In the holding member 81, the optical axis of the light condensed by the photodetection element 82 and the optical axis of the condenser lens 83 coincide with each other.

[0132] A flange portion 81a is formed on the holding member 81. The flange portion 81a is disposed between the bottom surface of the recessed portion 134 of the main body 131 and the fixing plate 133. In this state, the fixing plate 133 is mounted on the main body 131 by, for example, bolts, and the second photodetector 8 disposed on the bottom surface of the recessed portion 134 is fixed to the main body 131. In this way, the second photodetector 8 is disposed on one side of the beam splitter assembly 3 in the Z-axis direction and is supported by the second support structure 12. The second photodetector 8 detects the interference light L11 of the measurement light emitted from the beam splitter assembly 3.

[0133] The second light source 7 includes a holding member 71, a light emitting element 72, and a collimating lens 73. The holding member 71 holds the light emitting element 72 and the collimating lens 73. The light emitting element 72 emits a laser beam L10. The light emitting element 72 is, for example, a semiconductor laser such as a VCSEL. The collimating lens 73 collimates the laser beam L10 emitted from the light emitting element 72. In the holding member 71, the optical axis of the light emitting element 72 and the optical axis of the collimating lens 73 coincide with each other.

[0134] A flange portion 71a is formed on the holding member 71. The flange portion 71a is disposed between the frame 132 and the fixing plate 133. In this state, the fixing plate 133 is mounted on the main body 131 by, for example, bolts, and the second light source 7 disposed in the frame 132 is fixed to the main body 131. In this way, the second light source 7 is disposed on one side of the beam splitter assembly 3 in the Z-axis direction and is supported by the second support structure 12. The second light source 7 emits the laser light L10 that is incident on the beam splitter assembly 3.

[0135] As described above, the holding unit 130 holds the first photodetector 6, the second photodetector 8, and the second light source 7 so that the first photodetector (first optical device) 6, the second photodetector (second optical device) 8, and the second light source (third optical device) 7 face the same side and are arranged in the order of the first photodetector 6, the second photodetector 8, and the second light source 7. In the present embodiment, the holding unit 130 holds the first photodetector 6, the second photodetector 8, and the second light source 7 so that the first photodetector 6, the second photodetector 8, and the second light source 7 face the other side in the Z-axis direction (i.e., the beam splitter component 3 side) on one side in the Z-axis direction of the beam splitter component 3. In addition, the holding unit 130 holds the first photodetector 6, the second photodetector 8, and the second light source 7 so that they are arranged in the order of the first photodetector 6, the second photodetector 8, and the second light source 7 from one side in the X-axis direction (i.e., the light incident portion 4 side).

[0136] In addition, the first photodetector 6 is directed to a certain side, which means that the light receiving surface of the photodetection element 62 is directed to the certain side (that is, the first photodetector 6 is configured in a manner to detect light incident from the certain side). In this case, the lead pin of the photodetection element 62 extends, for example, to the side opposite to the certain side. Similarly, the second photodetector 8 is directed to a certain side, which means that the light receiving surface of the photodetection element 82 is directed to the certain side (that is, the second photodetector 8 is configured in a manner to detect light incident from the certain side). In this case, the lead pin of the photodetection element 82 extends, for example, to the side opposite to the certain side. In addition, the second light source 7 is directed to a certain side, which means that the light emitting surface of the light emitting element 72 is directed to the certain side (that is, the second light source 7 is configured in a manner to emit light to the certain side). In this case, the lead pin of the light emitting element 72 extends, for example, to the side opposite to the certain side. In addition, since the holding unit 130 is a part of the second supporting structure 12, the holding unit 130 holding a certain structure means that the certain structure is supported by the second supporting structure 12.

[0137] The first reflecting mirror 51, the second reflecting mirror 52, and the third reflecting mirror 53 are mounted on the main body 131 of the holding unit 130. The first reflecting mirror 51 is held by the holding unit 130 and is located on the opposite side of the first light detector 6 with respect to the first light passage hole 135. The second reflecting mirror 52 is held by the holding unit 130 and is located on the opposite side of the second light detector 8 with respect to the second light passage hole 136. The third reflecting mirror 53 is held by the holding unit 130 and is located on the opposite side of the second light source 7 with respect to the third light passage hole 137.

[0138] The first reflector 51 has the function of transmitting the measuring light L0 and reflecting the laser light L10, and is a dichroic mirror tilted relative to the optical axis of the first light detector 6. The first reflector 51 is arranged between the beam splitter assembly 3 and the first light detector 6. That is, the first reflector 51 is arranged in a manner opposite to the beam splitter assembly 3 and the first light detector 6. In this embodiment, the optical surface of the first reflector 51 is a surface parallel to the Y-axis direction and is a surface that forms an angle of 45° with the Z-axis direction. In addition, the optical axis of the first light detector 6 is parallel to the Z-axis direction.

[0139] The second reflector 52 has a function of reflecting a part of the laser light L10 and transmitting the remaining part of the laser light L10, and is a reflector (for example, a half reflector) parallel to the first reflector 51. The second reflector 52 is arranged so as to overlap with the first reflector 51 when viewed from the X-axis direction and overlap with the second photodetector 8 when viewed from the Z-axis direction. That is, the second reflector 52 is arranged so as to face the first reflector 51 and the second photodetector 8. In the present embodiment, the optical surface of the second reflector 52 is a surface parallel to the Y-axis direction and a surface forming an angle of 45° with the Z-axis direction.

[0140] The third reflector 53 has a function of reflecting the laser light L10, and is a reflector (for example, a total reflector) parallel to the second reflector 52. The third reflector 53 is arranged so as to overlap with the second reflector 52 when viewed from the X-axis direction and overlap with the second light source 7 when viewed from the Z-axis direction. That is, the third reflector 53 is arranged so as to face the second reflector 52 and the second light source 7. In the present embodiment, the optical surface of the third reflector 53 is a surface parallel to the Y-axis direction and a surface at an angle of 45° with the Z-axis direction.

[0141] The diaphragm 55 is mounted on the main body 131 of the holding unit 130. The diaphragm 55 is held by the holding unit 130 so as to be located between the first reflecting mirror 51 and the first photodetector 6. The diaphragm 55 is a member formed with a circular opening when viewed from the Z-axis direction, and is arranged in the first light passage hole 135.

[0142] Here, the optical path and the like between the beam splitter assembly 3 and the first photodetector 6 are described. The interference light L1 of the measurement light emitted from the beam splitter assembly 3 in the Z-axis direction is transmitted through the first reflector 51, enters the first photodetector 6 through the aperture 55, and is detected by the first photodetector 6. On the other hand, the laser light L10 emitted from the second light source 7 is reflected by the third reflector 53 and transmits the second reflector 52, and is reflected by the first reflector 51 and enters the beam splitter assembly 3 in the Z-axis direction. The interference light L11 of the laser light emitted from the beam splitter assembly 3 in the Z-axis direction is reflected by the first reflector 51 and the second reflector 52, and enters the second photodetector 8, and is detected by the second photodetector 8.

[0143] In the optical module 1, the length of the optical path between the beam splitter assembly 3 and the first photodetector 6 is shorter than the length of the optical path between the beam splitter assembly 3 and the second photodetector 8, and shorter than the length of the optical path between the beam splitter assembly 3 and the second light source 7. The length of the optical path refers to the physical distance along the optical path.

[0144] Specifically, the distance from the intersection of the optical path and the first reflector surface 31 of the beam splitter assembly 3 to the light incident surface of the first photodetector 6 is shorter than the distance from the intersection of the optical path and the first reflector surface 31 of the beam splitter assembly 3 to the light incident surface of the second photodetector 8, and is shorter than the distance from the intersection of the optical path and the first reflector surface 31 of the beam splitter assembly 3 to the light exit surface of the second light source 7. The distance from the intersection of the optical path and the first reflector surface 31 of the beam splitter assembly 3 to the light incident surface of the condenser lens 63 of the first photodetector 6 is shorter than the distance from the intersection of the optical path and the first reflector surface 31 of the beam splitter assembly 3 to the light incident surface of the condenser lens 83 of the second photodetector 8, and is shorter than the distance from the intersection of the optical path and the first reflector surface 31 of the beam splitter assembly 3 to the light exit surface of the collimator lens 73 of the second light source 7. The distance from the optical surface 33a of the beam splitter assembly 3 to the light incident surface of the first photodetector 6 is shorter than the distance from the optical surface 33a of the beam splitter assembly 3 to the light incident surface of the second photodetector 8, and is shorter than the distance from the optical surface 33a of the beam splitter assembly 3 to the light exit surface of the second light source 7. The distance from the optical surface 33a of the beam splitter assembly 3 to the light incident surface of the condenser lens 63 of the first photodetector 6 is shorter than the distance from the optical surface 33a of the beam splitter assembly 3 to the light incident surface of the condenser lens 83 of the second photodetector 8, and is shorter than the distance from the optical surface 33a of the beam splitter assembly 3 to the light exit surface of the collimator lens 73 of the second light source 7.

[0145] In the present embodiment, the light incident portion 4 is configured so that the angle of the holding member 41 relative to the frame 122 can be adjusted. In contrast, the first light detector 6 is positioned by the main body 131 when the holding member 61 is arranged on the bottom surface of the recess 134 of the main body 131. Therefore, in a state where the first light detector 6 is positioned, the angle of the holding member 41 can be adjusted while the measurement light L0 is incident on the beam splitter assembly 3, so that the detection intensity of the first light detector 6 becomes maximum. Furthermore, the light incident portion 4 can be fixed to the frame 122 in a state where the angle adjustment is performed.

[0146] Similarly, the second light source 7 is configured so that the angle of the holding member 71 relative to the frame 132 can be adjusted. In contrast, the second light detector 8 is positioned by the main body 131 when the holding member 81 is arranged on the bottom surface of the recessed portion 134 of the main body 131. Therefore, the angle of the holding member 71 can be adjusted while the second light detector 8 is positioned, so that the detection intensity of the second light detector 8 is maximized while emitting the laser light L10. Furthermore, the second light source 7 can be fixed to the frame 132 in the state where the angle adjustment is performed.

[0147] In addition, not only the light incident portion 4 but also the first light detector 6 may be configured to be able to adjust the angle of the holding member 61 relative to the frame body arranged on the bottom surface of the recessed portion 134 of the main body 131. Similarly, not only the second light source 7 but also the second light detector 8 may be configured to be able to adjust the angle of the holding member 81 relative to the frame body arranged on the bottom surface of the recessed portion 134 of the main body 131.

[0148] [Function and Effect]

[0149] In the reflector assembly 2, an optical functional component 13 is arranged between the reflector device 20 and the fixed reflector 16, and the optical functional component 13 is joined to the base 21 of the reflector device 20. As a result, the base 21 is stably held in a state where deformation of the base 21 is suppressed. Therefore, the movable reflector 22 can be operated with high precision in the reflector device 20. In addition, the light passing portion 24 constituting the first part of the optical path between the beam splitter assembly 3 and the fixed reflector 16 is arranged in the reflector device 20, and the light transmitting portion 14 constituting the second part of the optical path is arranged in the optical functional component 13. As a result, the interference optical system composed of the beam splitter assembly 3, the movable reflector 22 and the fixed reflector 16 can be efficiently arranged in space. According to the above description, the use of the reflector assembly 2 can compactly constitute a high-precision interference optical system.

[0150] In the reflector assembly 2, the second surface 21b of the base 21 and the third surface 13a of the optical function component 13 are bonded to each other by direct bonding. Thus, the base 21 of the reflector device 20 and the optical function component 13 can be firmly bonded.

[0151] Furthermore, in the reflector assembly 2, the third surface 13a of the optical functional component 13 (joining surface of the reflector device 20) extends in a manner opposite to the plurality of electrode pads 211 and 212 provided on the substrate 21 of the reflector device 20. Thus, the wires and the electrode pads 211 and 212 can be joined reliably.

[0152] In addition, in the reflector assembly 2, the fixed reflector 16 is formed on the fourth surface 13b of the optical functional component 13. As a result, it is possible to improve the positional accuracy and angle accuracy of the fixed reflector 16 relative to the movable reflector 22 of the reflector device 20. Furthermore, compared with the case where the fixed reflector 16 is spaced apart from the fourth surface 13b of the optical functional component 13, it is possible to reduce light loss.

[0153] Furthermore, in the reflector assembly 2, the optical function component 13 further includes a fifth surface 13d spaced apart from the reflector device 20 at least in a region facing the movable reflector 22. Thus, for example, even if the reference position when the movable reflector 22 is reciprocated (vibrated) in the Z-axis direction is located at the third surface 13a of the optical function component 13, the movable reflector 22 can be reciprocated in the Z-axis direction while preventing the movable reflector 22 from contacting the optical function component 13. In addition, as described later, the reference position when the movable reflector 22 is reciprocated in the Z-axis direction can be located at the third surface 13a of the optical function component 13, which is particularly effective in correcting the optical path difference generated between the optical path between the beam splitter assembly 3 and the movable reflector 22 and the optical path between the beam splitter assembly 3 and the fixed reflector 16.

[0154] Furthermore, in the reflector assembly 2, the reflector device 20 is constituted by the SOI substrate 100, the second surface 21b of the base 21 (the bonding surface with the optical functional component 13) is the surface of the device layer 102 on the side opposite to the intermediate layer 103, and the reflector surface 22a of the movable reflector 22 is provided on the surface of the device layer 102 on the side opposite to the intermediate layer 103. In the SOI substrate 100, the device layer 102 is thinner than the support layer 101, and therefore, for example, compared to "a structure in which the second surface 21b of the base 21 (the bonding surface with the optical functional component 13) is the surface of the support layer 101 on the side opposite to the intermediate layer 103, and the reflector surface 22a of the movable reflector 22 is provided on the surface of the device layer 102 on the side opposite to the intermediate layer 103", the reflector surface 22a of the movable reflector 22 can be brought closer to the optical functional component 13. Therefore, for example, the reference position when the movable reflector 22 is reciprocated in the Z-axis direction can be easily (with a small amount of movement) located at the third surface 13a of the optical functional component 13. Thus, a sufficient optical interference signal can be obtained while suppressing the amount of reciprocation of the movable reflector 22 in the Z-axis direction.

[0155] Furthermore, in the reflector assembly 2, the fifth surface 13d of the optical functional component 13 extends to the outer edge 13c of the optical functional component 13 when viewed from the Z-axis direction. Thus, even if there is gas in the region between the movable reflector 22 and the fifth surface 13d of the optical functional component 13, the gas is easily discharged from the region, and the movement of the movable reflector 22 can be suppressed from being hindered by the gas in the region. Thus, the voltage required to reciprocate the movable reflector 22 in the Z-axis direction can be reduced.

[0156] In the reflector assembly 2, a light passing portion 24 as a hole is formed in the reflector element 20, and a light transmitting portion 14 for correcting an optical path difference between an optical path between the beam splitter assembly 3 and the movable reflector 22 and an optical path between the beam splitter assembly 3 and the fixed reflector 16 is formed in the optical function component 13, and a surface 14a of the light transmitting portion 14 and a third surface 13a of the optical function component 13 are located on the same plane. Thus, for example, when the reference position of the movable reflector 22 when reciprocating in the Z-axis direction is located at the third surface 13a of the optical function component 13, the optical path difference between the two optical paths can be corrected in a manner that reduces the difference between the optical path length of the optical path between the beam splitter assembly 3 and the movable reflector 22 (the optical path length taking into account the refractive index of each medium through which the optical path passes) and the optical path length of the optical path between the beam splitter assembly 3 and the fixed reflector 16.

[0157] In particular, when each optical block 34, 35 and the optical functional component 13 are formed of the same material, since the material through which the light passes is the same, the generation of properties (dispersion) of differences in the refractive index due to the different wavelengths of each different material can be suppressed. That is, the optical path difference between the two optical paths can be corrected for all wavelength regions as the object. In addition, when each optical block 34, 35 and the optical functional component 13 are formed of similar materials, the optical path difference between the two optical paths can be corrected for a specific wavelength.

[0158] Furthermore, in the reflector assembly 2, the base 21 further includes a sixth surface 21d spaced apart from the optical functional component 13 in a region including at least a portion of the outer edge 21c of the base 21 when viewed from the Z-axis direction. Thus, when the second surface 21b of the base 21 and the third surface 13a of the optical functional component 13 are bonded to each other, the operation of the reflector device 20 can be performed by gripping the region of the base 21 where the sixth surface 21d is formed. By gripping the region of the base 21 where the sixth surface 21d is formed, the cleanliness of the second surface 21b of the base 21 (the bonding surface with the optical functional component 13) can be ensured, and as a result, a strong bonding between the base 21 and the optical functional component 13 can be achieved.

[0159] Furthermore, when the substrate 21 of the mirror device 20 and the optical functional component 13 are bonded at the chip level (one-to-one), good mirror devices 20 and good optical functional components 13 can be selected, thereby improving the yield of the mirror assembly 2.

[0160] Furthermore, in the reflector assembly 2, when viewed from the Z-axis direction, the outer edge 13c of the optical functional component 13 is located outside the outer edge 21c of the base 21. This allows the base 21 of the reflector device 20 to be firmly bonded to the optical functional component 13. Furthermore, the outer edge 21c of the base 21 can be protected.

[0161] Furthermore, in the reflector assembly 2, a stress relaxation substrate 17 is mounted on the fourth surface 13b of the optical functional component 13 via the fixed reflector 16. By setting the reflector assembly 2 on the setting object (the support body 9 in this embodiment) via the stress relaxation substrate 17, for example, even if the setting object is deformed, its influence on the interference optical system can be suppressed.

[0162] [Modifications]

[0163] The beam splitter assembly 3 can also be Fig.11 As shown in (a), the optical block 35 is formed with a first reflective mirror surface 31, a second reflective mirror surface 32 and a plurality of optical surfaces 33a and 33b. Fig.11 As shown in (b), an optical plate 36 having a first reflective mirror surface 31 and a member 37 having a second reflective mirror surface 32 are combined. Fig.11 In the beam splitter assembly 3 shown in (b), the optical plate 36 and the component 37 are spaced apart from each other.

[0164] In addition, in the reflector assembly 2, it is also possible to Fig.12 As shown in FIG. 1 , in the reflector device 20, the second surface 21b of the base 21 (the bonding surface with the optical functional component 13) is the surface of the support layer 101 on the opposite side to the intermediate layer 103, and the reflector surface 22a of the movable reflector 22 can be provided on the surface of the device layer 102 on the opposite side to the intermediate layer 103. In this case, as with the reflector surface 22a, a plurality of electrode pads 211 can be provided on the surface of the device layer 102 on the opposite side to the intermediate layer 103, thereby simplifying the manufacturing process of the reflector device 20 and simplifying the assembly process of the reflector assembly 2. In addition, even if the fifth surface 13d located on the fourth surface 13b side relative to the third surface 13a is not provided on the optical functional component 13, the support layer 101 can be made thinner at the portion corresponding to the movable reflector 22 and the drive unit 23, thereby preventing the movable reflector 22 and the drive unit 23 from contacting the optical functional component 13 when the movable reflector 22 is reciprocated in the Z-axis direction.

[0165] In addition, in the reflector assembly 2, it is also possible to Fig.13 , Fig.14 and Fig.15As shown, the movable mirror 22 and the driving unit 23 of the mirror device 20 are arranged in an airtight space (for example, an airtight space maintained at a high vacuum degree, or an airtight space filled with an inert gas such as nitrogen). Fig.13 , Fig.14 and Fig.15 The reflector assembly 2 shown has a reflector device 20, an optical functional component 13, a fixed reflector 16, a frame 18, and a light-transmitting component 19. The third surface 13a of the optical functional component 13 extends in a frame shape so as to surround the fifth surface 13d when viewed from the Z-axis direction. The third surface 13a extending in a frame shape is bonded to the second surface 21b of the base 21 of the reflector device 20. The optical functional component 13 and the base 21 are bonded to each other by direct bonding. The fixed reflector 16 is formed on the fourth surface 13b of the optical functional component 13.

[0166] The frame 18 is formed in a manner to surround the movable reflector 22 and the driving unit 23 of the reflector device 20 when viewed from the Z-axis direction, and is bonded to the first surface 21a of the base 21 of the reflector device 20. The frame 18 is formed of glass, for example, and is in the shape of a rectangular frame. The base 21 and the frame 18 are bonded to each other by direct bonding. The light-transmitting component 19 is formed in a manner to close the opening of the frame 18, and is bonded to the end face of the frame 18 on the opposite side of the reflector device 20. The light-transmitting component 19 is formed of glass, for example, and is in the shape of a rectangular plate. The frame 18 and the light-transmitting component 19 are bonded to each other by direct bonding. In addition, an AR coating (Anti Reflection Coating) for light of the sensitivity wavelength of the optical module 1 is applied to the surface of the light-transmitting component 19 on the side of the reflector device 20 in an area not bonded to the frame 18 (i.e., an area on the inner side of the frame 18 when viewed from the Z-axis direction).

[0167] In the present embodiment, a plurality of electrode pads 211 and one electrode pad 212 are arranged in a row along one portion and another portion of the outer edge of the substrate 21 extending in the X-axis direction. In each column, one electrode pad 212 is located in the center. In the frame 18, a pair of grooves 18a are formed in a manner corresponding to the plurality of electrode pads 211 and one electrode pad 212 in each column. In the light-transmitting component 19, a pair of grooves 19a are formed in a manner corresponding to the plurality of electrode pads 211 and one electrode pad 212 in each column. Thus, the wires can be connected to the electrode pads 211 and 212 through the grooves 18a and 19a.

[0168] exist Fig.13 , Fig.14 and Fig.15In the mirror assembly 2 shown, since the movable mirror 22 and the drive unit 23 of the mirror device 20 are arranged in an airtight space, the movable mirror 22 and the drive unit 23 can be maintained in a state of high reliability. In addition, by reducing the pressure in the airtight space, the movable mirror 22 and the drive unit 23 can be smoothly operated.

[0169] Fig.13 , Fig.14 and Fig.15 The reflector assembly 2 shown can be efficiently manufactured as follows. First, Fig.16 As shown in (a), a wafer 18W including a plurality of parts that respectively become the frame 18 and a wafer 19W including a plurality of parts that respectively become the light-transmitting member 19 are prepared, and the wafer 18W and the wafer 19W are bonded to each other by direct bonding in a manner that one frame 18 and one light-transmitting member 19 correspond to each other (first step). Here, in order to prevent the characteristics of the AR coating formed on the wafer 19W from changing, as the direct bonding, for example, plasma activated bonding, room temperature bonding, etc. can be selected.

[0170] Then, if Fig.16 As shown in (b), a wafer 20W including a plurality of parts that respectively become reflector devices 20 is prepared, and a wafer 18W (wafer 18W to which wafer 19W is bonded) and a wafer 20W are bonded to each other by direct bonding in a manner that one frame 18 and one reflector device 20 correspond to each other (second step). Here, as direct bonding, for example, plasma activated bonding, room temperature bonding, anodic bonding, etc. can be selected. Since it is difficult to mechanically apply external force to each reflector device 20 when bonding wafer 18W and wafer 20W, anodic bonding using attractive force generated by voltage application is particularly effective. When anodic bonding is selected as direct bonding, a wafer made of borosilicate glass is selected as wafer 18W.

[0171] Then, if Fig.17 As shown in (a), a wafer 13W including a plurality of parts that will become the optical functional components 13 is prepared, and a wafer 20W (wafer 20W bonded to wafer 18W and wafer 19W) and a wafer 13W are bonded to each other by direct bonding in a manner that one mirror device 20 corresponds to one optical functional component 13 (third step). Here, as direct bonding, for example, plasma activated bonding, room temperature bonding, etc. can be selected. In addition, a fixed mirror layer 16L including a plurality of parts that will become fixed mirrors 16 is formed in advance on the wafer 13W.

[0172] Then, if Fig.17As shown in (b), a wafer including a plurality of parts that respectively become reflector assemblies 2 (i.e., a plurality of parts each including a frame 18, a light-transmitting component 19, a reflector device 20, and an optical functional component 13) is cut into a plurality of reflector assemblies 2.

[0173] As described above, a wafer 13W including a plurality of parts that will become the optical functional component 13 (a wafer 13W on which the fixed mirror layer 16L is formed), a wafer 20W including a plurality of parts that will become the mirror device 20, a wafer 18W including a plurality of parts that will become the frame 18, and a wafer 19W including a plurality of parts that will become the light-transmitting member 19 are prepared, and after these are bonded at the wafer level (the order of bonding is not limited to the above order), the wafer including a plurality of parts that will become the mirror assembly 2 is cut into a plurality of mirror assemblies 2. Even if this cutting is performed by blade cutting using water, the movable mirror 22 and the drive unit 23 of the mirror device 20 are arranged in an airtight space, so that the movable mirror 22 and the drive unit 23 can be prevented from being damaged by water.

[0174] In addition, the materials of the optical functional component 13, the frame 18, and the light-transmitting component 19 are not limited to glass, and may be silicon, for example. In particular, the materials of the optical functional component 13 and the light-transmitting component 19 are selected according to, for example, the sensitivity wavelength of the optical module 1. When the sensitivity wavelength of the optical module 1 is in the near-infrared region, the materials are glass, and when the sensitivity wavelength of the optical module 1 is in the mid-infrared region, the materials are silicon. When the materials of the optical functional component 13, the frame 18, and the light-transmitting component 19 are glass, their shapes are formed by, for example, spray processing, etching, etc. When the materials of the optical functional component 13, the frame 18, and the light-transmitting component 19 are silicon, their shapes are formed by, for example, etching.

[0175] In addition, the light passing portion 24 of the reflector device 20 may also be Fig.18 As shown, the cutout is formed in the base body 21. Fig.18 In the reflector device 20 shown, not only the light passing portion 24 but also the light passing portion 25 are cutouts formed in the base 21. The light passing portion 24 is a cutout extending from the region between the pair of levers 261 of the base 21 to the outer edge 21c of the base 21. The light passing portion 25 is a cutout extending from the region between the pair of levers 271 of the base 21 to the outer edge 21c of the base 21. Fig.18 In the illustrated mirror device 20 , the first elastic support portion 26 does not include the first link member 262 , and the second elastic support portion 27 does not include the first link member 272 .

[0176] In addition, the optical functional component 13 may also be Fig.19As shown in (a) and (b), a light passing portion (second light passing portion) 13f is provided instead of the light transmitting portion 14. Fig.19 In the optical functional component 13 shown in (a), the light passing portion 13f is formed as a hole including a portion facing the movable mirror 22 and the driving portion 23 of the mirror device 20. Fig.19 In the optical functional component 13 shown in (b), the light passing portion 13 f is formed as a cutout including a portion facing the movable mirror 22 and the drive portion 23 of the mirror device 20 .

[0177] In addition, the drive unit 23 of the mirror device 20 may include three or more elastic support parts that elastically support the movable mirror 22. Furthermore, the drive unit 23 is not limited to being configured as an electrostatic actuator, and may be configured as a piezoelectric actuator, an electromagnetic actuator, or the like.

[0178] In addition, the second surface 21b of the base 21 and the third surface 13a of the optical functional component 13 may be bonded to each other by a method other than direct bonding (e.g., an adhesive such as a UV curing resin). In addition, the fixed reflector 16 may be spaced apart from the fourth surface 13b of the optical functional component 13 as long as it is arranged on the opposite side of the reflector device 20 relative to the optical functional component 13.

[0179] In addition, the structures of the reflector assembly 2 and the optical module 1 are not limited to the above materials and shapes, and various materials and shapes can be applied. In addition, the structures in one embodiment or modification example described above can be arbitrarily applied to the structures in other embodiments or modifications.

[0180] Description of Reference Numerals

[0181] 1…optical module, 2…reflector assembly, 3…beam splitter assembly, 13…optical functional component, 13a…third surface, 13b…fourth surface, 13c…outer edge, 13d…fifth surface, 14…light transmission portion (second light passing portion), 14a…surface, 16…fixed reflector, 17…stress relaxation substrate, 20…reflector device, 21…substrate, 21a…first surface, 21b…second surface, 21c…outer edge, 21d…sixth surface, 22…movable reflector, 24…light passing portion (first light passing portion), 100…SOI substrate (semiconductor substrate), 101…support layer, 102…device layer, 103…intermediate layer.

Claims

1. A reflector assembly, characterized in that: include: A reflector device comprising a substrate and a movable reflector, wherein the substrate has a first surface and a second surface opposite to the first surface, and the movable reflector is supported on the substrate in a manner movable along a first direction intersecting the first surface; and a component having a third surface opposite to the second surface, a fourth surface on the opposite side to the third surface, and a fifth surface spaced apart from the reflector device at least in a region opposite to the movable reflector, The second surface of the base and the third surface of the component are bonded to each other. The fifth surface of the component extends to the outer edge of the component as viewed from the first direction, A region between the movable reflector and the member is connected to a region located outside the base of the reflector device when viewed from the first direction.

2. A reflector assembly, characterized in that: include: A reflector device comprising a substrate and a movable reflector, wherein the substrate has a first surface and a second surface opposite to the first surface, and the movable reflector is supported on the substrate in a manner movable along a first direction intersecting the first surface; and a component having a third surface opposite to the second surface, a fourth surface on the opposite side to the third surface, and a fifth surface spaced apart from the reflector device at least in a region opposite to the movable reflector, The second surface of the base and the third surface of the component are bonded to each other. At least a portion of the outer edge of the base overlaps with the fifth surface of the component when viewed from the first direction, A region between the movable reflector and the member is connected to a region located outside the base of the reflector device when viewed from the first direction.

3. The reflector assembly according to claim 1 or 2, characterized in that: The second surface of the base and the third surface of the member are joined to each other by direct bonding.

4. The reflector assembly according to any one of claims 1 to 3, characterized in that: The reflector device is composed of a semiconductor substrate. The semiconductor substrate comprises a support layer composed of a first semiconductor layer, a device layer composed of a second semiconductor layer, and an intermediate layer composed of an insulating layer disposed between the support layer and the device layer. The second surface of the substrate is a surface of the device layer on the opposite side to the intermediate layer. The reflective mirror surface of the movable reflector is provided on a surface of the device layer on the intermediate layer side.

5. The reflector assembly according to any one of claims 1 to 4, characterized in that: The substrate further includes a sixth surface spaced apart from the member in a region including at least a portion of an outer edge of the substrate when viewed from the first direction.

6. The reflector assembly according to any one of claims 1 to 5, characterized in that: When viewed from the first direction, an outer edge of the component is located outside an outer edge of the base.

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