JP5151756B2 - Optical device - Google Patents

Description

  The present invention relates to an optical device that changes the reflection direction of a light beam.

Patent Document 1 discloses an optical device in which a mirror is supported by a pair of torsion bars. The pair of torsion bars are arranged on the same axis, extend in parallel with the substrate at a distance from the substrate, and the end on the anti-mirror side of each torsion bar is fixed to the substrate. Yes. In this case, when the torsion bar is twisted, the mirror swings around the extension line of the torsion bar, and the mirror is inclined with respect to the substrate.
If the distance between the substrate and the mirror is long when the substrate and the mirror extend in parallel, it is difficult to obtain a suction force for twisting the torsion bar by attracting one end of the mirror to the substrate. On the other hand, if the distance between the gaps is short, the mirror cannot be largely inclined with respect to the substrate.
In the technique of Patent Document 1, the torsion bar (that is, the swing axis of the mirror) is arranged at a position eccentric from the center of the mirror. According to this configuration, the mirror can be largely inclined while shortening the distance between the substrate and the mirror.

US Pat. No. 5,867,2020

  The optical device of Patent Document 1 is used for a projector or the like. If the mirror can be tilted greatly, the reflection direction of the light beam can be greatly changed. As a result, a large-diameter lens can be used, and a high-contrast projection image can be obtained. However, in order to tilt the mirror greatly, the torsion bar must be twisted greatly. For this purpose, it is necessary to lengthen the torsion bar and reduce the torsional rigidity of the torsion bar. Narrowing the torsion bar width can also reduce the torsional rigidity of the torsion bar, but due to manufacturing process limitations, there is a lower limit on the torsion bar width, which actually requires a longer torsion bar. .

There is a demand to reduce the size of optical devices. In particular, when a projector that forms a projection image by arranging a plurality of optical devices in a matrix form, there is a demand to provide a high-resolution bright image by closely arranging small optical devices. .
However, in the optical device of Patent Document 1, each of the pair of torsion bars is long, which prevents a small optical device from being densely arranged. In particular, the width in the extending direction of the torsion bar, that is, the direction along the swing axis of the mirror cannot be shortened. The optical device of Patent Document 1 is dissatisfied with the point that small optical devices cannot be densely arranged.

  The present invention provides an optical device that is compact and can be densely arranged.

The present invention provides an optical device that changes the reflection direction of a light beam by swinging a mirror around a swing axis.
The optical device of the present invention includes a substrate, a cantilever, a mirror, and an actuator. The base end of the cantilever is fixed to the substrate. The cantilever is spaced apart from the substrate at a height parallel to the substrate and extending in a direction perpendicular to the mirror swing axis. The cantilever has flexibility that can be bent and can be bent in a direction in which the tip of the cantilever approaches the substrate. The “bending” here is a generic term for a case where one or more bending points exist, and includes a case where the bending point is infinite and the whole is gently curved.

  The mirror is fixed to the tip of the cantilever beam. The mirror includes a plate-like portion extending from the distal end side to the proximal end side of the cantilever, and a reflection surface is formed on the opposite side of the plate-like portion. The light beam can be reflected by this reflecting surface. In addition, as for this reflective surface, another film | membrane which reflects a light beam may be formed in the surface of a plate-shaped part, and the surface of the plate-shaped part itself may form the reflective surface.

The actuator is formed between the tip of the cantilever and the vicinity of the part where the mirror is fixed (hereinafter referred to as a fixed part) and the substrate. The actuator generates a suction force that brings the fixed part closer to the substrate. The actuator only needs to generate an attractive force between the vicinity of the fixed part and the substrate. The mirror itself has conductivity, and an electrostatic attractive force is generated between the electrode disposed on the substrate side. It may be generated. Alternatively, an electrode may be disposed both in the vicinity of the fixed portion of the mirror and the substrate, and an electrostatic attractive force may be generated between the pair of electrodes. Alternatively, the Lorentz force may be generated by forming a coil in the vicinity of the fixed portion and generating a magnetic field using a permanent magnet or the like around the coil.
In the first aspect of the invention, the above-described actuator is expressed as a first actuator in order to distinguish it from the actuator used in the second aspect of the invention.

  When a suction force is generated by the first actuator, the tip of the cantilever is bent in a direction approaching the substrate, and the fixed part side of the mirror is bent in a direction approaching the substrate. The mirror swings around a swing axis that passes in the vicinity of the fixed part. The length of the mirror located on the tip side of the swing axis and within the range of bending toward the substrate is short, and the mirror can be largely inclined even if the distance between the mirror and the substrate is short. The mirror can be greatly tilted around the swing axis, and the reflection direction of the light beam can be greatly changed.

In the optical apparatus of the present invention, the mirror is swung by bending the cantilever. That is, the mirror is swung by the bending beam. On the other hand, in the optical device of Patent Document 1, the mirror is swung by twisting a torsion bar. That is, the mirror is swung by the torsion beam. When a bending beam and a torsion beam are compared, the bending beam has lower rigidity. Therefore, the bending beam can swing the mirror having the same shape with a shorter length than the twisting beam. By using a beam having a short length, it is possible to reduce that the length of the beam hinders miniaturization of the optical device. In the optical device of the present invention, since the bending beam is used, the width of the optical device can be reduced, and the small optical devices can be arranged at high density.
Moreover, the optical apparatus of patent document 1 has arrange | positioned the torsion bar in series. According to this configuration, the width of the optical device cannot be made smaller than the length of two beams. On the other hand, in the optical device of the present invention, the cantilevers are arranged in parallel. For this reason, the width of the optical device can be reduced to the length of one beam, and it can be reduced that the length of the beam hinders miniaturization of the optical device. The width of the optical device can be reduced, and small optical devices can be arranged at high density.

The mirror may further extend from the tip of the cantilever beyond the base of the cantilever. In this case, a second actuator is installed. The second actuator is formed between the extended portion of the mirror extending beyond the base end of the cantilever and the substrate, and generates a suction force that brings the extended portion closer to the substrate. This optical device is operated by selecting either the first actuator or the second actuator.
If the extension part and the second actuator are attached, the mirror located at the tip side of the cantilever can be brought closer to the substrate using the first actuator, or the proximal end of the cantilever can be used using the second actuator. The part of the mirror located on the side can be brought closer to the substrate. As a result, the mirror can be swung to both sides around the swing axis, and the directivity direction of the mirror can be greatly changed. The reflection direction of the light beam can be changed greatly.

  A pair of cantilevers may extend in parallel across the mirror. When the mirror is supported by a pair of cantilever beams extending in parallel across the mirror, the mirror can be prevented from being twisted and the mirror can be stably swung in a plane perpendicular to the rocking axis. Can do. The reflection direction of the light beam can be stably changed in one plane.

When providing an extension part in a mirror and attaching a 2nd actuator, it is effective to provide a slit in a mirror. In this case, a pair of slits extending in parallel with the cantilever and a slit connecting the ends of the pair of slits on the front end side of the cantilever are formed.
When the above-described slit is provided, a portion surrounded on three sides by the slit is formed. This portion is continuous with the extended portion of the mirror and is inclined according to the inclination angle of the extended portion of the mirror. For this reason, when a suction force is generated between the extended portion of the mirror and the substrate by the second actuator, the portion surrounded on three sides by the slit is inclined more than the portion outside the slit. If the light beam is reflected at the portion surrounded by the slits, the reflection direction of the light beam can be further changed.

A slit may be formed in the mirror, and the cantilever may be accommodated in the slit. In this case, a single cantilever beam can realize a symmetrical structure with the cantilever beam as the axis of symmetry.
If the number of cantilever beams that support the mirror can be reduced to one, the area ratio of the mirror in the optical device can be increased. Thereby, the reflection efficiency of the light beam can be increased.

  The first actuator can be composed of an electrode fixed to the substrate and an electrode fixed to the mirror. In this case, the distance from the base end of the cantilever to the electrode on the substrate side may be equal to the distance from the base end of the cantilever to the electrode on the mirror side. On the other hand, the distance from the base end of the cantilever to the electrode on the substrate side may be shorter than the distance from the base end of the cantilever to the electrode on the mirror side. According to the latter configuration, it is possible to generate a suction force that draws the distal end side of the cantilever beam toward the proximal end side of the cantilever beam. As a result, the mirror fixed to the tip of the cantilever can be greatly inclined. Thereby, the mirror can be largely swung around the swing axis, and the reflection direction of the light beam can be greatly changed.

  According to the present invention, by bending the cantilever, the mirror fixed to the tip of the cantilever can be greatly inclined. The reflection direction of the light beam can be greatly changed by largely swinging the mirror around the swing axis. In the optical apparatus according to the present invention, since the bending beam (cantilever beam) is used, the mirror can be swung with a beam having a short length. Moreover, cantilever beams can be arranged in parallel. This can reduce the length of the beam from hindering the miniaturization of the optical device. The width of the optical device can be reduced, and small optical devices can be arranged at high density. A high-resolution projection image can be generated.

The main features of the embodiment described below are organized.
(Feature 1) The substrate is made of silicon single crystal.
(Feature 2) The cantilever and the plate-like portion are made of silicon single crystal containing impurities.
(Feature 3) An aluminum film is used as the reflective film.

(First embodiment)
FIG. 1 is a plan view of the optical device 2 according to the first embodiment, and FIG. 2 is a front view of the optical device 2. When the optical device 2 is used, one optical device 2 can be used alone, but a plurality of optical devices 2 can also be arranged and used in one or two dimensions. If arranged in one dimension, a one-dimensional projection image can be generated, and if arranged in two dimensions, a two-dimensional projection image can be generated. In this embodiment, a description will be given of one optical device 2.

  The optical device 2 includes a substrate 10 (see FIG. 2), support columns 20a and 20b, cantilever beams 22a and 22b, a mirror structure 38, and electrodes 12a and 12b on the substrate side (see FIG. 2). Yes. The mirror structure 38 includes a silicon film 34 and an aluminum film 36 spreading in a flat plate shape. An arrow D1 indicates the distal end side of the cantilever beams 22a and 22b, and an arrow D2 indicates the proximal end side of the cantilever beams 22a and 22b.

  The substrate 10 is formed of silicon single crystal. As shown in FIG. 2, the columns 20 a and 20 b extend vertically upward from the surface of the substrate 10. The pillars 20a and 20b are made of silicon single crystal containing impurities, and are connected to an electric circuit (the electric circuit configuration is omitted in FIGS. 1 and 2) formed on the surface layer portion of the substrate 10. ing. The end (base end 22a1) on the D2 side of the cantilever 22a is fixed to the support column 20a. The end portion (base end 22b1) on the D2 side of the cantilever beam 22b is fixed to the support column 20b. The cantilever 22a and the cantilever 22b are formed of a silicon single crystal containing impurities. The support column 20a and the cantilever beam 22a are integrated and electrically connected. The support column 20b and the cantilever beam 22b are integrated and electrically connected. Note that there is no particular limitation on the positions of the columns 20a and 20b in the direction D1-D2. As shown in FIG. 1, the support columns 20a and 20b may exist at the center of the width in the D1-D2 direction of the optical device 2, or may exist on the D1 side or D2 side of the center position.

  The silicon film 34 is formed of a silicon single crystal containing impurities. An end portion vicinity 34a on the D1 side of the silicon film 34 is fixed to an end portion (tip 22a2) on the D1 side of the cantilever 22a. An end portion vicinity 34a on the D1 side of the silicon film 34 is fixed to an end portion (tip 22b2) on the D1 side of the cantilever 22b. An end portion vicinity 34a on the D1 side of the silicon film 34 is fixed to the tip 22a2 of the cantilever 22a, and at the same time, is fixed to the tip 22b2 of the cantilever 22b. The silicon film 34, the cantilever beam 22a, and the cantilever beam 22b are integrated and electrically connected. The potential of the entire silicon film 34 is fixed via an electric circuit formed on the surface layer portion of the substrate 10.

The silicon film 34 includes a portion 34b extending from the end portion vicinity 34a on the D1 side toward the base ends 22a1 and 22b1 of the cantilever 22a and the cantilever 22b, and a portion extending from the portion 34b in the D2 direction. 34c and a portion 34d extending in the D2 direction. The silicon film 34 has a flat plate shape as a whole.
On the surfaces of the portions 34a, 34b, 34c, and 34d of the silicon film 34, an aluminum film 36 that reflects a light beam is formed. A mirror structure 38 is formed by stacking the silicon film 34 and the aluminum film 36. The cantilever 22a and the cantilever 22b extend in the D1-D2 direction on both sides of the mirror structure 38.
Electrodes 12 a and 12 b are formed on the surface of the substrate 10. The electrode 12a is formed at a position facing the vicinity of the portion 34a of the silicon film 34, and the electrode 12b is formed at a position facing the vicinity of the portion 34d of the silicon film 34.

  When a voltage is applied to the electrode 12 a to form a potential difference between the electrode 12 a and the silicon film 34, an electrostatic attractive force can be applied between the electrode 12 a and the vicinity of the portion 34 a of the silicon film 34. Similarly, when a voltage is applied to the electrode 12b to form a potential difference between the electrode 12b and the silicon film 34, an electrostatic attractive force can be applied between the electrode 12b and the vicinity of the portion 34d of the silicon film 34. The optical device 2 is used by switching between a state in which a voltage is applied to the electrode 12a, a state in which a voltage is applied to the electrode 12b, and a state in which no voltage is applied to any electrode.

  3A and 3B show operation diagrams of the optical device 2. FIG. The optical device 2 can alternately take the states shown in FIGS. In FIG. 3A, an electrostatic attractive force is generated between the electrode 12a and the vicinity of the portion 34a of the silicon film 34. In this case, the portion 34 a approaches the substrate 10, and the tips of the cantilevers 22 a and 22 b that support the mirror structure 38 are bent in a direction approaching the substrate 10. As a result, the end vicinity 34d on the D2 side is inclined away from the substrate 10. When the position of the swing shaft 26 of the mirror structure 38 at this time is observed, it is not on the base ends 22a1 and 22b1 of the cantilever beams 22a and 22b but on the front end 22a2 and 22b2 side of the cantilever beams 22a and 22b. I understand that.

In the optical device 2, the distance from the swing shaft 26 to the D1 side edge 34e of the silicon film 34 is short (compared to the distance from the support columns 20a, 20b to the D1 side edge 34e of the silicon film 34). The silicon film 34 is not prevented from inclining with respect to the substrate 10 until the large inclination angle θ ₁ is obtained. Even if the pillars 20a and 20b are low and the distance between the cantilevers 22a and 22b and the substrate 10 is short, the silicon film 34 can be largely inclined. Here, the “tilt angle” indicates a displacement angle from a state in which the mirror structure 38 is parallel to the substrate 10. The light beam 40 incident on the aluminum film 36 is reflected in the reflection direction 42.

In FIG. 3B, an electrostatic attractive force is generated between the electrode 12b and the vicinity of the portion 34d of the silicon film 34. In this case, the portion 34d approaches the substrate 10, and the cantilevers 22a and 22b are curved so that the tips 22a2 and 22b2 are displaced upward. As a result, the mirror structure 38 is tilted around the swing shaft 26 in such a direction that the end portion vicinity 34 a on the D1 side is away from the substrate 10. The inclination angle of the mirror structure 38 at this time is theta _2. The light beam 40 incident on the aluminum film 36 is reflected in the reflection direction 44.
When the mirror structure 38 swings counterclockwise around the swing shaft 26, the distance from the swing shaft 26 to the edge Df of the silicon film 34 on the D2 side is long (from the pillars 20a, 20b to the silicon film 34). Even if it is pulled until the vicinity of the end portion 34d on the D2 side of the silicon film 34 comes into contact with the substrate 10 (relative to the distance to the end edge 34f on the D2 side), a large inclination angle cannot be obtained. θ ₂ <θ ₁ is satisfied. However, when (a) and (b) in FIG. 3 are compared, the mirror structure 38 of the optical device 2 is inclined clockwise by θ _{1 and} counterclockwise by θ ₂ from the horizontal position. At the same time, the inclination angle is switched by θ ₁ + θ ₂ . Obviously, when the reflection directions 42 and 44 are compared, the reflection direction is largely switched.

  When an electrostatic attractive force is alternately generated on the D1 side and the D2 side to repeatedly displace the cantilever, a load is applied to the cantilever. In the optical device 2, since the mirror structure 38 is supported by the pair of cantilevers 22a and 22b, the mirror structure 38 is supported even if the rigidity of each of the cantilevers 22a and 22b is lowered to facilitate bending. can do. Rather than supporting the mirror structure 38 with a single cantilever beam, the load applied to the cantilever beam can be reduced and the durability can be improved.

As shown in FIG. 1, the width of the optical device 2 in the direction parallel to the swing shaft 26 is the width W, and the width of the optical device 2 in the direction orthogonal to the swing shaft 26 is the width L. FIG. 4 is a plan view of the optical device 3 in which the widths W and L of the optical device 2 are reduced. The width W 1 of the optical device 3 in the direction parallel to the swing shaft 26 is smaller than the width W of the optical device 2. The width L3 of the optical device 3 in the direction orthogonal to the swing shaft 26 is smaller than the width L of the optical device 2. The optical device 2 and the optical device 3 differ only in width, and the other configurations are the same. For this reason, the detailed description regarding the structure of the optical apparatus 3 is abbreviate | omitted.
When the width of the optical device 2 is reduced, the torque of the mirror is reduced. For this reason, the optical device 3 requires a beam with low rigidity in order to largely swing the mirror. However, since the optical device 2 uses bending beams (cantilever beams 22a and 22b), the rigidity of the beams is sufficiently small. Even if the widths W and L are reduced, it is not necessary to increase the length of the beam to further reduce the rigidity. That is, since the optical device 2 uses a bending beam, the width of the optical device can be reduced without being limited by the length of the beam. As a result, the small optical devices 3 can be arranged with high density.
In the optical device 2, the cantilevers 22a and 22b are arranged in parallel. If the cantilever beams 22a and 22b are arranged in series, the width is smaller than the width of twice the length of the cantilever beams 22a and 22b (the width of the portion 34b in the direction perpendicular to the swinging shaft 26). It cannot be downsized. In the optical device 2, since the beams can be arranged in parallel, the width of the optical device can be reduced without being limited by the length of the beam. As a result, the small optical devices 3 can be arranged with high density.

(Second embodiment)
FIG. 5 shows a plan view of the optical device 4 of the second embodiment. The optical device 4 is different from the optical device 2 only in the mirror structure 58, and the other configuration is the same as that of the optical device 2. For this reason, detailed description of portions other than the mirror structure 58 is omitted. Hereinafter, also in the third and fourth embodiments, only portions different from the optical device 2 will be described, and redundant description will be omitted.

The mirror structure 58 includes a silicon film 54, an aluminum film 56, and a slit 55. An aluminum film 56 is formed on the surface of the silicon film 54. The slit 55 is formed from three slit portions.
The pair of slits 55a and 55b extends in parallel with the cantilever beams 22a and 22b. The third slit 55c connects the end portions 55a1 and 55b1 on the D1 side of the pair of slits 55a and 55b.
In the vicinity of the D2 side ends of the pair of slits 55a and 55b, the narrow portions 52a and 52b are formed outside the vicinity of the D2 side ends of the pair of slits 55a and 55b. Is formed. An end portion vicinity 58d on the D2 side of the mirror structure 58 is connected to the narrow portions 52a and 52b. Therefore, when the end portion 58d on the D2 side of the mirror structure 58 is brought close to the substrate 10, the narrow portions 52a and 52b are bent at the center. An aluminum film 56 is formed on the surface of the portion 57 surrounded by the slit 55 in the three directions.

  FIG. 6 shows a front view of the optical device 4 when an electrostatic attractive force is generated on the D2 side. Since the portion 57 is connected to the end vicinity 58d on the D2 side of the mirror structure 58, the portion 57 is inclined by the same angle as the inclination angle of the end vicinity 58d on the D2 side of the mirror structure 58.

If electrostatic attraction is generated between the electrodes 12b and 32b, the narrow portion 52a, D1-side portion than 52b is inclined by theta ₃ counterclockwise. At that time, since the narrow portions 52a and 52b are easily bent, the vicinity of the end portion 58d on the D2 side of the mirror structure 58 is more greatly inclined. Thus, the aluminum film 56 formed on the surface of the portion 57 which is surrounded on three directions by the slit 55 is inclined by the same angle as the inclination angle theta ₄ of D2 side of the end portion 58d of the mirror structure 58. θ ₃ <θ ₄ is satisfied.
As a result, the aluminum film 56 is inclined more than the inclination angle θ ₂ of the first embodiment shown in FIG. θ ₃ <θ ₄ and θ ₂ <θ ₄ are also satisfied.
In the optical device 4, the aluminum film 56 can be greatly inclined counterclockwise, and the reflection direction of the light beam incident on the aluminum film 56 can be greatly changed.

(Third embodiment)
FIG. 7 is a plan view of the optical device 6 according to the third embodiment. The optical device 6 is different from the optical device 2 only in the mirror structure 68, the support column 21, and the cantilever beam 23, and the other configuration is the same as that of the optical device 2. The mirror structure 68 includes a silicon film 64, an aluminum film 66, and a slit 65. An aluminum film 66 is formed on the surface of the silicon film 64. The slit 65 is formed so that the center position of the width in the direction orthogonal to the D1-D2 direction of the mirror structure 68 extends in the D1-D2 direction. The support column 21 and the cantilever beam 23 exist inside the slit 65. The end portion on the D2 side of the cantilever beam 23 is fixed to the column 21. The cantilever beam 23 extends from the end fixed to the column 21 to the D1 side. The end vicinity 34a on the D1 side of the mirror structure 68 is fixed to the tip of the cantilever 23.
It is preferable that the slit 65 has a shape along the shapes of the support column 21 and the cantilever beam 23. In FIG. 7, the width of the slit 65 in the same direction is reduced according to the width of the cantilever 23 in the direction orthogonal to the D1-D2 direction. Thereby, the occupation area ratio of the aluminum film 66 in the optical device 6 can be improved, and the reflection efficiency of the light beam can be increased.

  In the optical device 6, the mirror structure 68 is swingably supported by one cantilever beam 23. Thereby, the occupation area ratio of the reflection surface of the mirror structure 68 in the optical device 6 can be made larger than when two cantilever beams are used. Thereby, the reflection efficiency of the light beam can be increased.

(Fourth embodiment)
FIG. 8 shows a front view of the optical device 8 of the fourth embodiment. The optical device 8 is different from the optical device 2 only in the configuration that generates an electrostatic attractive force between the substrate 10 and the mirror structure 38, and the other configuration is the same as that of the optical device 2. The optical device 8 includes support columns 70a and 70b, cantilever beams 72a and 72b, and a mirror structure 78. The mirror structure 78 includes a silicon film 74 and an aluminum film 76. The columns 70a and 70b, the cantilevers 72a and 72b, and the silicon film 34 are formed of silicon single crystal and are insulators. The electrode 32a exists on the D1 side of the surface of the mirror structure 78 on the substrate 10 side. The electrode 32b exists on the D2 side of the surface of the mirror structure 38 on the substrate 10 side. The electrode 13a exists on the D1 side of the substrate 10. If the distance from the support column 20a to the electrode 13a is L1, and the distance from the support column 20a to the electrode 32a on the D1 side of the mirror structure 38 is L2, in the optical device 8, the distance L1 is smaller than the distance L2. According to this configuration, when an electrostatic attractive force is generated between the electrode 32a and the electrode 13a, as shown in FIG. 9, a force 74 that attracts the tips of the cantilevers 22a and 22b toward the columns 20a and 20b is generated. can get. This force, the cantilever 22a, the tip portion of 22b is largely curved, can be tilted largely mirror structure 38 until the inclination angle theta _5. The inclination angle θ ₅ is larger than the inclination angle θ ₁ of the first embodiment shown in FIG. By largely swinging the mirror structure 38 around the swing shaft 26, the reflection direction of the light beam can be greatly changed.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. For example, a coil may be wound around each of the electrodes 32a and 32b on the mirror structure 38 instead of the electrode, and a magnetic field may be generated around the coil using a permanent magnet or the like. Thereby, a Lorentz force may be generated, and the mirror structure 38 may be swung.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The top view of the optical apparatus of 1st Example is shown. The front view of the optical apparatus of 1st Example is shown. (a) and (b) schematically show the operating principle of the optical apparatus of the first embodiment. The top view of the optical apparatus which reduced in size the optical apparatus of 1st Example is shown. The top view of the optical apparatus of 2nd Example is shown. The front view in operation | movement of the optical apparatus of 2nd Example is shown. The top view of the optical apparatus of 3rd Example is shown. The front view of the optical apparatus of 4th Example is shown. An operation principle of the optical device according to the fourth embodiment is schematically shown.

Explanation of symbols

2: Optical device 10: Substrates 12a, 12b; Electrodes 20a, 20b: Supports 22a, 22b: Cantilever 26: Oscillating shaft 34: Silicon film 36: Aluminum film 38: Mirror structure D1: Tip direction of cantilever D2: Proximal direction of the cantilever

Claims (5)

A substrate,
A beam having a base end fixed to the substrate and having a bendable flexibility;
The plate is fixed to the distal end of the beam, extends from the distal end side to the proximal end side of the beam, and includes a plate-like portion that can swing around the swing axis with respect to the substrate,
An apparatus in which the plate-like portion includes a pair of slits in a direction orthogonal to the swing axis and a slit that connects ends of the pair of slits on the distal end side of the beam. A first actuator for generating a suction force for bringing the distal end side of the beam of the plate-like portion closer to the substrate;
A second actuator for generating a suction force for bringing the base end side of the beam of the plate-like portion closer to the substrate;
The apparatus according to claim 1, wherein either the first actuator or the second actuator can be selected and operated. The plate-like portion has a reflecting surface on the opposite side as viewed from the substrate;
The apparatus according to claim 1, wherein one end of the reflecting surface is in contact with the slit. The first actuator includes a substrate side electrode fixed to the substrate, and a plate portion side electrode fixed to the plate portion,
The distance along the direction in which the beam extends from the base end of the beam to the center of the substrate side electrode is the distance along the direction in which the beam extends from the base end of the beam to the center of the plate side electrode. 3. The device of claim 2, which is shorter. An optical device that changes the reflection direction of a light beam by swinging a mirror around a swing axis,
A substrate,
A base end is fixed to the substrate, and a height apart from the substrate is parallel to the substrate and extends in a direction perpendicular to the swing axis, and has flexibility to bend. Cantilever,
The plate is fixed to the tip of the cantilever, and includes a plate-like portion extending from the tip of the cantilever toward the base end, and a reflection surface is formed on the side opposite to the plate-like portion. Mirror
The tip of the cantilever and the vicinity of the portion where the mirror is fixed and the substrate are provided, and includes a first actuator that generates a suction force that brings the portion closer to the substrate,
The mirror extends beyond the proximal end from the tip of the cantilever;
A second actuator that is formed between an extension portion extending beyond the base end and the substrate, and that generates a suction force that brings the extension portion closer to the substrate;
It is configured to select and operate either the first actuator or the second actuator,
An optical device in which a pair of slits extending in parallel with the cantilever and a slit connecting the end portions on the tip side of the pair of slits are formed in the mirror.

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