WO2004038485A1

WO2004038485A1 - Optical switch and optical device

Info

Publication number: WO2004038485A1
Application number: PCT/JP2003/013484
Authority: WO
Inventors: Katsuhiko Kurumada; Toshiaki Tamamura; Masatoshi Kanaya; Tohru Ishizuya
Original assignee: Ntt Electronics Corporation; Nikon Corporation
Priority date: 2002-10-22
Filing date: 2003-10-22
Publication date: 2004-05-06
Also published as: JPWO2004038485A1; AU2003275584A8; AU2003275584A1

Abstract

An optical switch using a vibration-resistant mirror having a high reflectance. The optical switch comprises an optical waveguide substrate (230), a mirror portion (118) and a movable portion (231) on which the mirror portion (118) is mounted. The mirror portion (118) has a light-reflecting portion (101) and a supporting portion (102) for supporting the light-reflecting portion (101) on the movable portion (231). The optical waveguide substrate (230) has a groove (247) into which the light-reflecting portion (101) is inserted by the movable portion (231) for switching over the optical path, and a recess (250) for receiving a part of the supporting portion (102) when the light-reflecting portion (101) is inserted into the groove (247).

Description

TECHNICAL FIELD The present invention relates to an optical switch and an optical device having an optical element formed by a thin film. 2. Description of the Related Art An optical switch that switches an optical path by moving a minute mirror into an optical path by moving a minute mirror in Japanese Patent Application Laid-Open No. 2000-142223 (Patent Document 1). Is disclosed. This optical switch forms a movable electrode plate with a micro mirror mounted by micro-machining technology. The reflection surface of the minute mirror is perpendicular to the main plane of the movable electrode plate. A fixed electrode is disposed at a position facing the movable electrode plate, and the movable electrode plate is moved by electrostatic force by applying a voltage between the movable electrode plate and the fixed electrode. With this structure, a very small mirror is inserted into the optical path or taken out of the optical path.

In addition, in this optical switch, a photo resist film having a thickness equivalent to the height of a mirror is formed on a thin film to be a movable electrode plate in order to form a mirror on the movable electrode plate. A mirror-shaped etching hole is provided in the photoresist film, a metal film is grown in the etching hole by plating, and the photoresist film is removed.

Also, Japanese Patent Application Laid-Open No. 2001-142008 (Patent Document 2) An optical switch is disclosed in which a mirror is mounted on an actuator and the mirror is moved into the optical path by the actuator to switch the optical path.

In Sensors and Actuators A, 33 (1992) 249-256, "Microfabricated Hinges" (Non-Patent Document 1), a film serving as a plate is formed on a substrate, and this plate is applied to the substrate. It is disclosed that by raising vertically, a plate perpendicular to the substrate is formed. In the process of forming a film serving as a plate, a hinge structure for connecting one end of the plate to the substrate is formed. The plate is raised around the hinge to form a fine vertical structure. DISCLOSURE OF THE INVENTION As described above, the micro mirror of the optical switch described in Patent Literature 1 is provided with an etching hole in a photo resist film formed thick by the height of a mirror, and plating the etching hole with a plating method. It is formed by filling a metal film with a metal. Therefore, the mirror surface has a shape obtained by inverting the surface shape of the side surface of the etching hole. With the current photoresist film etching technology, it is difficult to control the angle of the side surface of the etching hole with respect to the main plane, and it is also difficult to smooth the surface roughness of the side surface. For this reason, it was difficult to manufacture a mirror having a high reflectance with a reflecting surface perpendicular to the movable electrode plate by the method described in Patent Document 1.

In addition, Patent Document 2 does not describe in detail the minute mirror structure and the manufacturing method.

In addition, it is conceivable to apply the configuration described in Non-Patent Document 1 in which the plate is vertically raised and supported by a hinge to a mirror of an optical switch, but a plate formed by a thin film process is considered. The three-dimensional structure formed by the thin film process Since the structure is supported vertically by a hinge made of steel, it is easy to generate gas and it is difficult to obtain strength. This makes it difficult to keep the plate perpendicular to the substrate surface.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical switch using a mirror having a high reflectivity and being resistant to vibration.

To achieve the above object, according to the present invention, the following optical switch is provided.

That is, it has an optical waveguide substrate, a mirror portion, and a movable portion on which the mirror portion is mounted,

The mirror unit includes: a light reflection unit; and a support unit that supports the light reflection unit on the movable unit.

The optical waveguide substrate includes a groove into which the light reflecting portion is inserted by the movable portion for switching an optical path, and a groove formed by the supporting portion when the light reflecting portion is inserted into the groove. An optical switch having a concave portion into which a part enters.

In the above-mentioned optical switch, the light reflecting portion and the supporting portion can be constituted by respective films, and at this time, the supporting portion has one end fixed to the movable portion and the other end. The portion is connected to the light reflecting portion directly or via another member, and is curved from the one end to the other end to form a main plane of a film constituting the light reflecting portion. Can be supported non-parallel to the main plane of the optical waveguide substrate.

In the above optical switch, the other end of the supporting portion is located at a position higher than a lower end of the light reflecting portion, and suspends the light reflecting portion directly or via the other member. When the light reflecting portion is inserted into the groove, the concave portion of the optical waveguide substrate has the support. 03 013484

Four

The other end of the holding portion may be configured to enter.

In the optical switch, the support portion may be disposed on both sides of the light reflection portion, and may be configured to support the light reflection portion from both sides. The concave portion of the optical waveguide substrate may include: It is possible to arrange on both sides of the groove corresponding to the support parts on both sides of the light reflection part.

In the above optical switch, the groove and the concave portion may be continuous, and the groove and the concave portion may be filled with oil for refractive index matching. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is a cross-sectional view taken along the line AA of the optical switch according to the embodiment of the present invention in a state where a voltage is applied and the movable plate 2 31 is lowered, and FIG. FIG. 3 is a sectional view taken along line AA of FIG.

FIG. 2 is a top view of the optical switch according to the embodiment of the present invention.

FIG. 3 is a cutaway perspective view of the optical waveguide substrate 240 of the optical switch according to the embodiment of the present invention.

FIG. 4 is a cutaway perspective view of the mirror structure substrate 230 of the optical switch according to the embodiment of the present invention.

FIG. 5A is a cross-sectional view of a mirror 118 used in the optical switch according to the embodiment of the present invention, and FIG. 5B is a view taken in the direction of arrow B in FIG. 5A. . FIG. 6 is a perspective view of a mirror 118 used for the optical switch according to the embodiment of the present invention.

FIG. 7 is a top view showing the arrangement of the movable plate 231 on the mirror structure substrate 230 in the optical switch according to the embodiment of the present invention.

FIGS. 8A to 8C are cross-sectional views of the optical switch according to the embodiment of the present invention, showing the manufacturing steps of the mirror-structured substrate 230 taken along the line CC. 9 (a) to 9 (c) are cross-sectional views of the optical switch according to the embodiment of the present invention, taken along the line C-C, each showing a step of manufacturing the mirror structure substrate 230.

FIG. 10 is a top view showing the optical switch according to the embodiment of the present invention, in a state before the final asshing step is performed in the manufacturing process of the mirror-structured substrate 230.

FIG. 11 (a) is a D-D cross-sectional view showing the shape of another mirror 117 that can be mounted on the optical switch according to the embodiment of the present invention, and FIG. 11 (b) is FIG. 7 is a front view of the reflecting portion 101 of the mirror 111 viewed from the back side. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an optical switch according to an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1A, the optical switch according to the present embodiment is fixed by sandwiching an optical waveguide substrate 240 and a mirror structure substrate 230 with a spacer (not shown). Are arranged at intervals. The space between the optical waveguide substrate 240 and the mirror structure substrate 230 is filled with a matching oil (refractive index matching liquid) that matches the refractive index of the optical waveguide of the optical waveguide substrate 240. I have.

As shown in FIGS. 2 and 3, the optical waveguide substrate 240 has optical waveguides 21, 24, 24, etc., and optical waveguides 244, 245, 246, etc. in advance. They are arranged so that they intersect at a defined angle. These optical waveguides 241 to 246 are embedded in an optical waveguide substrate 240. At the intersection of the optical waveguides 2 4 1, 2 4 2, 2 4 3, etc. with the optical waveguides 2 4 4, 2 4 5, 2 4 6, etc., the mirror 1 1 8 of the mirror structure substrate 2 3 0 A groove 247 is provided for insertion of a groove. The opening direction of the groove 247 is shown in Fig. 1 (a) and Fig. 3. As described above, it is directed to the mirror structure substrate 230 side (lower side). By inserting the reflecting portion 101 of the mirror 110 of the mirror structure substrate 230 into the groove 247 as shown in FIG. 1B, one of the intersecting optical waveguides is transmitted. The light to be conveyed is reflected and made incident on the other optical waveguide to perform a switching operation.

As shown in FIGS. 1 (a) and 4, the U moving plate 2 31 is mounted on the mirror structure substrate 230, and the mirror 1 18 is mounted on the movable plate 2 31. The movable plate 2 3 1 is composed of a three-layer film in which a silicon nitride film, an A 1 film, and a silicon nitride film are sequentially laminated, and has a rectangular mirror mounting plate 2 3 1 b for mounting the mirror 1 18. And two strip-shaped support plates 2311c connected to the ends of the mirror mounting plate 2311b. The support plate 2311c has at each end a leg 2311a. The leg 2 31 a is fixed to the substrate 230. The movable plate 231 is a mirror-structured substrate at room temperature due to the internal stress generated by the difference in thermal expansion coefficient between the silicon nitride film and the A1 film, and the internal stress generated during film formation. Is formed so as to be curved upward. As a result, the movable plate 2 31 lifts up the mirror mounting plate 2 3 1 b side with the leg 23 la as a fulcrum, as shown in FIG. Can be inserted into the groove 2 4 7.

Further, the A1 film constituting the movable plate 231, is connected to the wiring in the substrate 230 through the leg 23la. Further, electrodes (not shown) are arranged in the substrate 230 so as to face the movable plate 231. Therefore, by applying a voltage between the A1 film of the movable plate 23 1 and an electrode (not shown) inside the substrate 230, the movable plate 2 31 is attracted to the substrate 230 by electrostatic force. Then, as shown in FIG. 1 (a), it comes into close contact with the substrate 230. As a result, the mirror 118 can be taken out of the groove 247 of the optical waveguide substrate 240. Although FIGS. 1 and 4 show a state in which only one movable plate 231 is mounted on the mirror structure substrate 230, the optical waveguides 241, etc. in FIG. In order to insert the mirror 1 18 into that of the groove 2 4 7 at the point where the movable plate 2 3 1 is actually arranged, as shown in Fig. 7, a plurality of movable plates 2 3 1 are arranged side by side vertically and horizontally. Mirror 1 1 1 8 is mounted on 2 3 1. At that time, the mirror mounting plate 23 lb of the movable plate 231, which is in contact with the movable plate 231, is disposed between the support plate 231c of the movable plate 231 and the inside thereof. With such an arrangement, the mirrors 118 can be arranged on the substrate 230 with high density.

Next, the configuration of the mirror 118 mounted on the movable plate 231 will be described.

As shown in FIGS. 5 (a), (b) and FIG. 6, the mirror 1 18 has two strip-shaped support portions 102, two connection portions 104, and two strip-shaped portions. , A reflecting portion 101, and a reflecting portion supporting portion 105. Both the support portion 102 and the support portion 103 are curved in an arc shape in the longitudinal direction. The connecting portion 104, the reflecting portion supporting portion 105 and the reflecting portion 101 have a step (return) at an edge in order to increase rigidity.

One end of each of the two support portions 102 is fixed to the movable plate 231 by a leg portion 102c. The upper ends of the support portions 103 are connected to the tips of the two support portions 102 via the connection portions 104, respectively. The two support portions 103 hang downward, and the tips support both ends of the reflection portion support portion 105. The reflecting portion 101 is mounted on the reflecting portion supporting portion 105. Therefore, the reflecting portion support portion 105 on which the reflecting portion 101 is mounted is configured to be suspended by the two supporting portions 103.

The support 102 is a two-layer film in which a silicon nitride film 102a and an A1 film 102b are stacked as shown in FIG. Support part 103 is A 1 membrane This is a two-layer film in which 103 a and a silicon nitride film 103 b are stacked. Each of the supporting portions 102 and 103 is curved in an arc shape by the stress generated by the difference in the thermal expansion coefficient between the A1 film and the silicon nitride film and the stress generated during the film formation. At this time, as shown in FIGS. 5 (a) and 6, the support portion 102 is formed so as to be curved upward with respect to the movable plate 231, whereas the support portion 1 Numeral 03 is formed so as to be curved downward, opposite to the supporting portion 102. For this purpose, the support portion 102 is laminated in the order of the silicon nitride film 102 a and the A 1 film 102 b from the movable plate 23 1 side, and the support portion 103 is formed of the movable plate 23 The A1 film 103a and the silicon nitride film 103b are stacked in this order from the first side.

By bending the supporting portion 103 in the opposite direction to the supporting portion 102 in this way, as shown in FIG. 5 (a), the position where the reflecting portion 101 is supported is moved to the movable plate 23. In the horizontal direction, the reflecting portion 101 can be supported at a position close to the leg portion 102c of the supporting portion 102. As a result, in the mirror 118, the reflecting portion 101 is less likely to vibrate, and the position of the reflecting portion 101 is stabilized.

As described above, the structure of the mirror 111 has an advantage that the reflecting portion 101 is hard to vibrate, but the structure in which the reflecting portion supporting portion 105 is suspended by the supporting portion 103 is provided. The connecting portion 104 exists at a high position near the upper end of the reflecting portion 101. Therefore, as shown in FIG. 1 (b), when the mirror 1 18 is lifted by the movable plate 2 3 1 and the reflecting portion 101 is inserted into the groove 2 47 of the optical waveguide substrate 240, There is a possibility that the connecting portion 104 and the supporting portions 102 and 103 come into contact with the optical waveguide substrate 230 and hinder insertion of the reflecting portion 101 into the groove 247.

In order to solve this problem, according to the present embodiment, as shown in FIGS. 1 (a) and 1 (b) and FIG. 2, the contact is provided on both sides of the groove 247 of the optical waveguide substrate 240. A concave portion 250 into which the connecting portion 104 and the supporting portions 102 and 103 can enter is formed. The concave portions 250 are provided on both sides of the groove 247, at least in the regions where the connecting portions 104 and the supporting portions 102 and 103 are inserted. In FIGS. 1 and 2, a wide area is provided inside the rhombic region surrounded by the optical waveguides 241 on both sides of the groove 247. However, a certain distance is provided from the optical waveguide 241 so that the concave portion 250 does not affect the propagation light of the optical waveguide 241 and the like. The depth of the concave portion 250 is designed according to the height of the connecting portion 104. In FIG. 1, the groove is formed so as to have the same depth as the groove 247. As a result, even when the reflecting portion 101 is hard to vibrate and the hanging mirror 118 is used, the reflecting portion 101 is not sufficiently provided in the groove 247 of the optical waveguide substrate 240. Can be inserted to depth. Therefore, a high-performance optical switch having a large extinction ratio can be provided as the optical switch.

In FIGS. 1 and 2, the groove 247 is formed so as to be continuous with the concave portions 250 on both sides thereof. As a result, the adjacent grooves 247 are continuous by the concave portions 250. By adopting such a configuration, when the reflecting portion 101 of the mirror 118 is inserted into the groove 247 filled with the matching oil, the matching oil is formed in the concave portion 250, which is a wide left and right space. Therefore, the effect of reducing the resistance when the reflecting portion 101 is inserted into the groove 247 can be obtained.

The operation of the optical switch according to the present embodiment will be described using a mirror 118 at a position where the optical waveguides 242 and 245 intersect as an example. In a state in which a voltage is applied between the A1 film of the movable plate 23 1 and the electrode inside the substrate 230, the movable plate 2 31 is moved by the electrostatic force to the substrate 2 as shown in Fig. 1 (a). The mirror 110 is attracted to 30 and the reflecting portion 101 of the mirror 118 is located below the groove 247 of the optical waveguide substrate 240. Therefore, for example, the optical waveguide 242 The light to be carried propagates through the optical waveguide 242 as it is across the groove 247. On the other hand, when no voltage is applied between the A1 film of the movable plate 231 and the electrode inside the substrate 230, the movable plate 231 bends as shown in FIG. The reflecting portion 101 of 118 is inserted into the groove 247, and the connecting portion 104 and the supporting portions 102, 103 are inserted into the concave portions 250 on both sides of the groove. Thus, for example, the light propagating through the optical waveguide 242 is reflected by the reflecting portion 101 in the groove 247, and is turned back, enters the optical waveguide 245, and Propagate 5. Thus, light propagating through the optical waveguide 242 can be extracted from the optical waveguide 245, and switching in the light propagation direction can be realized.

As for the reflecting portion 101 of the mirror 118, as shown in FIG. 6, the surface facing the substrate 230 side at the time of manufacturing has a higher reflectance, and is suitable for use as a reflecting surface. . Therefore, the direction in which the mirror 1 18 is mounted on the movable plate 2 3 1 is adjusted so that the surface in FIG. 6 of the reflection section 101 becomes the reflection surface according to the direction of light propagation of the optical waveguide substrate 240. It is desirable to determine

Next, a method of manufacturing the optical waveguide substrate 240 will be described. In the present embodiment, 2 4 1 like optical waveguides of the optical waveguide substrate 2 4 0 is formed by S i 0 ₂ with increased refractive index by doping impurities. Further, clad portion around the optical waveguide path is formed by S i 0 _2. As a manufacturing procedure, first, an Si substrate is prepared, a lower cladding layer is formed by depositing glass particles on the Si substrate by a flame deposition method, and impurities are doped thereon by a flame deposition method. The formed optical waveguide layer of the glass fine particles is formed. Thereafter, heat treatment is performed to make the lower cladding layer and the optical waveguide layer into a transparent glass state. Next, the optical waveguide layer is subjected to dry etching to form the optical waveguides 241 to 246 as shown in FIG. On top of this, glass particles are deposited again by the flame deposition method, forming an upper cladding layer, The optical waveguides 241 to 246 are covered. Further heat treatment turns the upper clad layer into a transparent glass state. Finally, a groove 247 and a recess 250 are formed by dry etching or wet etching. As described above, the optical waveguide substrate 240 can be manufactured.

Next, the manufacturing method of forming the movable plate 2 31 and the mirror 118 on the mirror structure substrate 230 will be described with reference to FIGS. 8 (&) to ( ₀ ) and FIGS. 9 (&) to (0). This will be described with reference to FIG.

First, the movable plate 23 1 is formed on the substrate 230. A resist layer 28 1 is formed on a substrate 230 on which electrodes and wirings (not shown) are formed in advance, and the positions where the legs 2 31 a of the movable plate 2 31 are to be formed are located. An opening (not shown) is formed by photolithography (FIG. 8 (a)). O This resist layer 281, which is a sacrificial layer, is removed in the last step. Next, a silicon nitride film is formed on the upper surface of the resist layer 281, and an opening is provided in the silicon nitride film at the bottom of the opening. Further, an A1 film is formed, and a silicon nitride film is stacked thereon. The three-layered film of the silicon nitride film, the A1 film, and the silicon nitride film becomes the movable plate 231. The thickness and the film forming conditions of the silicon nitride film and the A1 film are set to predetermined film thickness and film forming conditions so that the movable plate 231 is warped upward. Thereafter, the silicon nitride film, the A1 film, and the silicon nitride film formed in the above-described process are transferred to the shape of the movable plate 231 shown in FIG. 7 by photolithography and etching. To synchronize. Thus, the movable plate 231 in which the A1 film is connected to the wiring of the substrate 230 at the position of the leg 231a can be formed.

Next, a mirror 1 18 is formed on the movable plate 2 3 1. The support portions 102, 103, the connection portion 104, the reflection portion support portion 105, and the reflection portion 101 of the mirror 118 are arranged on the movable plate 231 as shown in FIG. It is formed into a shape. FIGS. 8 (a) to (c) and FIGS. 9 (a) to (c) show C-C of FIG. The manufacturing procedure of the mirror 118 in the cross section is shown.

First, a resist layer 81 is formed on the entire surface of the substrate 230 on which the movable plate 231 is formed, and an opening 8 la is formed at a position where the leg 102 c of the support 102 is to be formed. It is formed by photolithography (Fig. 8 (a)). Next, a resist island 201 is formed at a position where the connecting portion 104 and the reflecting portion supporting portion 105 are to be formed (FIG. 8B). By forming the resist island 201, the connecting portion 104 and the reflecting portion supporting portion 105 can be formed into a shape having a step around the periphery. An A1 film 103a of the support portion 103 is formed on the entire surface of the substrate 230 in this state, and the support portion 103 shown in FIG. 10 is formed by photolithography and etching. Figure 3 (c). Next, a silicon nitride film and an A1 film 102b are sequentially formed on the entire surface (FIG. 9A). After patterning the formed A1 film 102b into the shape of the support portion 102 of FIG. 1 ◦, the silicon nitride film formed in the above process is changed to the support portion 102, the connection portion 104, The support portion 103 and the reflective portion support portion 105 are patterned into a shape (FIG. 9B). Thus, the silicon nitride film 103b of the support portion 103, the connection portion 104, and the reflection portion support portion 105 are formed at a time.

A resist layer 141 is formed on the entire surface of the substrate 230 in the state shown in FIG. An opening is formed (Fig. 9 (c)). A resist layer 82 is further formed thereon, and the resist layer is removed except for the reflecting portion 101, thereby forming a resist island. By forming the resist island, the reflecting portion 101 can be formed into a shape having a step 101 a around the reflecting portion 101. An opening is also formed in the resist layer 82 of the resist island at a position to be the connection portion 105b. An A1 film 101 is formed on the entire surface of the substrate 230 in this state, and is patterned into the shape of the reflecting portion 101 (FIG. 9 (c)). This allows As shown in FIG. 10, the movable plate 231, the support portions 102, 103, the connection portion 104, and the reflection portion support portion sandwiching the sacrificial layers 281, 81, 141, etc. 105 and the reflecting portion 101 can form a laminated substrate 230.

Finally, the resist layers 281, 81, 141, 82 of the sacrificial layer are removed by asshing. As a result, the supporting portions 102 and 103 are curved and rise up on the movable plate 231, as shown in FIG. 6, to have the shape of the mirror 118 in FIG. Further, the movable plate 2 31 also curves, rises with respect to the substrate 230 as shown in FIG. 1 (b), and is brought into a state in which the mirror 1 18 can be moved up and down. As described above, the mirror structure substrate 230 can be manufactured.

Finally, the optical waveguide substrate 240 and the mirror structure substrate 230 are aligned, and the spacers are interposed and fixed. Then, a matching oil is injected into a space between the optical waveguide substrate 240 and the mirror structure substrate 230 to seal the space. As a result, the optical switch according to the present embodiment can be manufactured.

As described above, the optical switch according to the present embodiment has a configuration in which a mirror 111 is formed by vertically raising a reflecting portion 101 formed of a thin film by supporting portions 102 and 103. Therefore, the main plane of the thin film can be used as the reflecting surface of the reflecting portion 101. Therefore, since the reflecting surface can be easily formed smoothly, a high reflectance can be obtained. In addition, the mirror 118 can support the reflecting portion 101 at a low position close to the movable plate 231, by suspending the reflecting portion supporting portion 105. Hard to vibrate. Moreover, since the concave portion 250 is provided in the optical waveguide substrate 240, even when the hanging mirror 110 is used, the connecting portion 104 and the supporting portions 102, 100 are used. The reflecting portion 101 can be inserted all the way into the groove 247 without the 3 hitting the optical waveguide substrate 240. Therefore, it is strong against vibration and extinction ratio It is possible to provide a large optical switch.

Further, the mirror that can be used for the optical switch according to the above-described embodiment is not limited to the above-mentioned mirror 118. The optical waveguide substrate provided with the concave portion 250 as in the present embodiment is effective when the mirror supporting the reflecting portion uses a mirror having a structure present on both sides of the reflecting portion. For example, as shown in Figs. 11 (a) and (b), the reflector 101 is suspended downward from the two supports 102 on both sides (movable plate 2 31 side). Can be used. This mirror 117 also has the advantage that the height of the reflecting portion 101 from the movable plate 231 is low, and the reflecting portion 101 is unlikely to vibrate even when the movable plate 231 moves. Since the upper end of the supporting portion 102 is the same height as the upper end of the reflecting portion 101, the depth of the concave portion 250 is equal to or greater than that of the groove 247. Formed.

Further, in the above-described embodiment, the groove 247 of the optical waveguide substrate 240 and the concave portions 250 on both sides are made continuous, but it is not always necessary to make them continuous. Further, depending on the arrangement of the mirror support, it is possible to provide the concave portion 250 only in the portion where the mirror support collides with the optical waveguide substrate 240.

Further, in the above-described embodiment, the concave portion 250 of the optical waveguide substrate 240 is formed by etching, but it is also possible to form the concave portion 250 by other methods such as mechanical addition without being limited to etching. It is.

As described above, according to the present invention, it is possible to provide an optical switch using a mirror having a high reflectance and a high resistance to vibration.

In FIG. 1, by stopping the position of the movable plate 2 31 at a desired height, in the configuration of the present embodiment, the reflecting portion 101 of the mirror 118 is stopped in the middle of the optical path. Can be. For example, it can be stopped at a height that blocks a desired amount of light, such as half or 1/3 of the light flux. As a result, this implementation It can be used as a light attenuator (attenuator) that allows only the desired amount of light to pass through the optical switch. In this case, it is possible to mount a film having a low light reflectance as a light-shielding portion instead of the reflecting portion 101 of the mirror 118. Further, instead of the reflecting portion 101, it is also possible to mount a polarizing film having a polarization characteristic or an optical thin film having a light wavelength filter characteristic. By mounting these on the movable plate 231, optical devices such as a polarizer and a wavelength selector can be configured.

Claims

The scope of the claims

1. It has an optical waveguide substrate, a mirror portion, and a movable portion on which a part of the mirror is mounted,

The optical waveguide substrate includes a groove into which the light reflecting portion is inserted by the movable portion for switching an optical path, and a groove formed by the supporting portion when the light reflecting portion is inserted into the groove. An optical switch characterized by having a recess into which a part enters.

2. The optical switch according to claim 1,

The light reflecting portion and the supporting portion are each formed of a film, and the supporting portion has one end fixed to the movable portion, and the other end connected to the light reflecting portion directly or through another member. The main surface of the film constituting the light reflecting portion is non-aligned with respect to the main surface of the optical waveguide substrate by being curved from the one end to the other end. An optical switch characterized in that it is configured to be supported in parallel.

3. The optical switch according to claim 2,

The other end of the support portion is located at a position higher than a lower end of the light reflection portion, and the light reflection portion is suspended directly or via the other member,

The optical switch, wherein when the light reflecting portion is inserted into the groove, the other end of the support portion enters the concave portion of the optical waveguide substrate.

4. The optical switch according to claim 2 or 3,

The support portion is disposed on both sides of the light reflection portion, and is configured to support the light reflection portion from both sides,

The optical switch, wherein the concave portion of the optical waveguide substrate is disposed on both sides of the groove, corresponding to the support portions on both sides of the light reflecting portion.

5. The optical switch according to claim 1, 2, 3, or 4,

The groove and the recess are continuous, and the groove and the recess are filled with oil for refractive index matching.

6. It has an optical waveguide substrate, an optical element, and a movable part on which the optical element is mounted,

The optical element includes: an optical film having desired optical characteristics; and a support unit that supports the optical film on the movable unit.

The optical waveguide substrate includes a groove into which the optical film is inserted by the movable portion, and a recess into which a part of the support portion enters when the optical film is inserted into the groove. An optical device, comprising:

7. The optical device according to claim 6, wherein

The support portion is formed of a film, one end is fixed to the movable portion, the other end is connected to the optical film directly or through another member, and the other end is connected to the other end. An optical device having a configuration in which the main plane of the optical film is supported non-parallel to the main plane of the optical waveguide substrate by curving toward the end of the optical waveguide.

8. The optical device according to claim 7,

The other end of the support portion is located at a position higher than a lower end of the optical film, and has a configuration in which the optical film is suspended directly or through the other member.

The optical device, wherein when the optical film is inserted into the groove, the other end of the support portion enters the concave portion of the optical waveguide substrate.

9. The optical device according to claim 7 or 8,

The support portion is disposed on each side of the optical film, and supports the optical film from both sides.

The optical device according to claim 1, wherein the concave portion of the optical waveguide substrate is disposed on both sides of the groove, corresponding to the support portions on both sides of the optical film.

10. The optical device according to claim 6, 7, 8, or 9,

The optical device, wherein the groove and the concave portion are continuous, and the groove and the concave portion are filled with oil for refractive index matching.

11. The optical device according to claim 6, 7, 8, 9, or 10, wherein the optical film is formed of a film that blocks light, and functions as a light amount attenuator.