JP5767939B2 - Mirror array - Google Patents

Description

  The present invention relates to a mirror array including a plurality of mirrors and an actuator for driving the mirrors.

  2. Description of the Related Art Conventionally, a mirror device that rotates a mirror about a main axis and a sub axis that are orthogonal to each other is known. For example, Patent Document 1 discloses a mirror device including four actuators for one mirror. Specifically, two sets of actuators are provided on both sides of the mirror main axis, that is, two sets. In each set, the two actuators are arranged with the secondary shaft in between. Each actuator includes a plate-like actuator main body extending in the sub-axis direction and a counter electrode provided to face the actuator main body. Each actuator body tilts so as to be attracted to the counter electrode by electrostatic attraction between the counter electrode. In the mirror device configured as described above, the mirror rotates about the main axis by tilting any two actuators downward. Depending on which set of actuators is tilted, the rotation direction around the main axis of the mirror can be switched. On the other hand, by tilting the actuator located on one side with respect to the secondary shaft in both sets, the mirror rotates about the secondary shaft. Depending on which side of the actuator is tilted with respect to the secondary shaft, the rotation direction of the mirror around the secondary shaft can be switched.

JP 2009-229916 A

  By the way, in a mirror array including a plurality of mirrors, the number of actuators increases according to the number of mirrors. Therefore, it is preferable to simplify the configuration of the mirror and the actuator in order to increase the number of mirrors included in the mirror array.

  The technology disclosed herein has been made in view of such a point, and an object thereof is to simplify the configuration of the mirror array.

  The mirror array disclosed herein includes a base portion, a plurality of mirrors supported by the base portion, and a plurality of actuators coupled to the mirror to drive the mirror, and the mirrors are orthogonal to each other. And rotating around the auxiliary shaft. The actuator includes an actuator body extending in the sub-axis direction and a piezoelectric element laminated on the surface of the actuator body, and is configured to tilt the actuator body by expanding and contracting the piezoelectric element. Each of the mirrors is provided with two actuators arranged on both sides of the auxiliary shaft on only one side with respect to the main shaft.

  According to the above configuration, two actuators are provided for each mirror. That is, the number of actuators per mirror is reduced compared to the mirror device described in Patent Document 1. Therefore, the configuration of the mirror array can be simplified.

  Also, in the configuration in which the piezoelectric element is laminated on the surface of the actuator body, the actuator body can be tilted to the opposite side of the surface on which the piezoelectric element is laminated by extending the piezoelectric element, while the piezoelectric element is contracted. By doing so, the actuator body can be tilted to the piezoelectric element side. Therefore, even if the actuator is provided only on one side with respect to the main axis of the mirror, the mirror can be rotated in any direction around the main axis.

  Furthermore, since the two actuators provided for each mirror are arranged with the secondary shaft in between, the mirror can be rotated around the secondary shaft by tilting one of the actuators. At this time, the rotation angle around the secondary axis of the mirror can be increased by tilting the other actuator to the side opposite to the one actuator.

  That is, even in a simple configuration in which the actuator is provided only on one side with respect to the main axis of the mirror, the mirror can also be moved around the main axis by using the actuator as a piezoelectric drive and arranging the two actuators in parallel with the auxiliary shaft in between. It can also be rotated around the auxiliary shaft.

  According to the mirror array, the mirror array can be simplified without impairing the mirror drive performance.

It is a top view of the mirror array which concerns on embodiment. It is a bottom view of a mirror array. It is sectional drawing in the III-III line | wire of FIG. 1 of a mirror array. It is the schematic of a wavelength selective switch. It is a top view of the 1st hinge. It is a top view of the 2nd hinge. It is a top view of the basic model used for simulation. It is a top view of model 0 of the 1st hinge. It is a top view of the model 1 of a 1st hinge. It is a top view of the model 2 of a 1st hinge. It is a top view of the model 3 of a 1st hinge. It is explanatory drawing for demonstrating the main-axis direction component and sub-axis direction component of a filament part. It is a top view of the model 4 of a 1st hinge. It is a top view of the model 5 of a 1st hinge. It is a top view of the model 6 of a 1st hinge. It is a top view of the model 7 of a 1st hinge. It is a top view of the model 8 of a 1st hinge. It is a top view of the model 9 of a 1st hinge. It is explanatory drawing for demonstrating the main-axis direction component and sub-axis direction component of a filament part. It is a top view of the model 10 of a 1st hinge. It is a top view of the model 11 of a 1st hinge. It is a top view of the model 12 of a 1st hinge. It is a top view of the model 13 of a 1st hinge. It is a top view of the model 14 of a 1st hinge. It is a top view of the model 15 of a 1st hinge. It is a top view of the model 16 of a 1st hinge.

  Hereinafter, exemplary embodiments will be described in detail with reference to the drawings.

  1 is a plan view of the mirror array 100, FIG. 2 is a bottom view of the mirror array 100, and FIG. 3 is a cross-sectional view of the mirror array 100 taken along line III-III in FIG.

  The mirror array 100 includes a frame-shaped base portion 2, a plurality of actuators 1, 1,..., A plurality of mirrors 110, 110,..., A first hinge 6 that connects each actuator 1 to the mirror 110, and each mirror. The 2nd hinge 7 which connects 110 to the base part 2, and the control part 120 which controls actuator 1,1, ... are provided. Two actuators 1 and 1 are provided for each mirror 110. That is, each mirror 110 is driven by two actuators 1 and 1. Specifically, the mirror 110 rotates about the main axis X and the sub axis Y that are orthogonal to each other.

The mirror array 100 is manufactured using an SOI (Silicon on Insulator) substrate 200. The SOI substrate 200 includes a first silicon layer 210 made of single crystal silicon, an oxide film layer 220 made of SiO ₂ , and a second silicon layer 230 made of single crystal silicon in this order. Configured.

  The mirror array 100 is used by being incorporated in a wavelength selective switch 300, for example. FIG. 4 shows a schematic diagram of the wavelength selective switch 300.

  The wavelength selective switch 300 includes one input optical fiber 310, three output optical fibers 320 to 340, a collimator 350 provided on the optical fibers 310 to 340, a spectroscope 360 formed of a diffraction grating, A lens 370 and a mirror array 100 are provided. In this example, there are only three output fibers, but the present invention is not limited to this.

  In the wavelength selective switch 300, a plurality of optical signals having different wavelengths are input via the input optical fiber 310. This optical signal is collimated by the collimator 350. The optical signal that has become parallel light is demultiplexed into a predetermined number of optical signals of a specific wavelength by the spectroscope 360. The demultiplexed optical signal is collected by the lens 370 and enters the mirror array 100. The number of specific wavelengths to be demultiplexed and the number of mirrors 110 in the mirror array 100 correspond to each other. In other words, the demultiplexed optical signals having specific wavelengths are incident on the corresponding mirrors 110 respectively. Then, the optical signal is reflected by each mirror 110, passes through the lens 370 again, and enters the spectroscope 360. The spectroscope 360 combines a plurality of optical signals having different wavelengths and outputs them to the output optical fibers 320 to 340. Here, the mirror array 100 adjusts the reflection angle of the optical signal by rotating each mirror 110 around the main axis, and switches which output optical fiber 320 to 340 the corresponding optical signal is input to. . More specifically, when changing the rotation angle around the main axis of each mirror 110 in order to switch the output optical fibers 320 to 340 for inputting an optical signal, the mirror 110 is rotated around the sub-axis about the main axis. Change the rotation angle. This prevents the reflected light from the mirror 110 from being input to an undesired output optical fiber when changing the rotation angle around the main axis.

  Next, the configuration of the mirror array 100 will be described in detail.

  The base portion 2 is formed in a substantially rectangular frame shape although the entire illustration is omitted. Most of the base portion 2 is formed of the first silicon layer 210, the oxide film layer 220, and the second silicon layer 230.

  The mirror 110 is formed in a substantially rectangular plate shape. The mirror 110 is formed by forming an Au / Ti film on the surface of the first silicon layer 210.

  The first hinge 6 has one end connected to the tip of the actuator 1 and the other end connected to the edge of the mirror 110. The detailed shape of the first hinge 6 will be described later. 1-3, the 1st hinge 6 is simplified and shown in figure. Two first hinges 6 and 6 are connected to the mirror 110. That is, the two actuators 1 and 1 are connected to the mirror 110 via the first hinges 6 and 6. The two first hinges 6 and 6 are connected to positions symmetrical with respect to the midpoint of the edge of the mirror 110. The first hinge 6 is formed of the first silicon layer 210.

  One end of the second hinge 7 is connected to the edge of the mirror 110 that faces the end edge to which the first hinge 6 is connected. On the other hand, the other end of the second hinge 7 is connected to the base portion 2. The detailed shape of the second hinge 7 will be described later. 1-3, the 2nd hinge 7 is simplified and shown in figure. The second hinge 7 is connected to the midpoint of the edge of the mirror 110. The second hinge 7 is formed of the first silicon layer 210.

  Each actuator 1 includes a base portion 2, an actuator body 3 coupled to the base portion 2, a piezoelectric element 4 formed on the surface of the actuator body 3, and a counter electrode provided to face the actuator body 3. And 5.

  The actuator body 3 has a base end connected to the base portion 2. The actuator body 3 is supported by the base portion 2 in a cantilever manner. The first hinge 6 is connected to the tip of the actuator body 3. The actuator body 3 is formed of the first silicon layer 210. The actuator body 3 is formed integrally with a portion of the base portion 2 formed by the first silicon layer 210.

  The piezoelectric element 4 is formed on the surface 31 of the actuator body 3 (the surface opposite to the surface 32 facing the counter electrode). The piezoelectric element 4 includes a lower electrode 41, an upper electrode 43, and a piezoelectric layer 42 sandwiched therebetween. The lower electrode 41, the piezoelectric layer 42, and the upper electrode 43 are laminated on the surface 31 of the actuator body 3 in this order. The piezoelectric element 4 is formed of a member different from the SOI substrate 200. Specifically, the lower electrode 41 is formed of a Pt / Ti film. The piezoelectric layer 42 is formed of lead zirconate titanate (PZT). The upper electrode 43 is formed of an Au / Ti film.

  The piezoelectric layer 42 is provided over the entire area of the actuator body 3 in the longitudinal direction. The piezoelectric layer 42 also extends from the base end portion of the actuator body 3 to the base portion 2 side. The piezoelectric layer 42 is connected to the piezoelectric layer 42 of another adjacent actuator on the base portion 2. That is, the piezoelectric layers 42, 42,... Of the four actuators 1, 1,.

  The upper electrode 43 includes a main body 43a provided on a portion of the piezoelectric layer 42 on the actuator main body 3, and a terminal (hereinafter referred to as an “upper terminal”) provided on a portion of the piezoelectric layer 42 on the base portion 2. 43b, and a connecting portion 43c for connecting the main body 43a and the terminal 43b. The connecting portion 43c is thinner than the main body 43a and the terminal 43b.

  The lower electrode 41 has substantially the same shape as the piezoelectric layer 42 and is located below the piezoelectric layer 42. Therefore, the lower electrode 41 is basically not exposed to the outside. However, only the terminal (hereinafter also referred to as “lower terminal”) 41a of the lower electrode 41 is exposed to the outside. The lower terminal 41a of the lower electrode 41 is common to the lower electrodes 41, 41,... Of the four actuators 1, 1,.

  The counter electrode 5 is configured integrally with the base portion 2. The counter electrode 5 is provided to face the base end portion 33 of the actuator body 3. A gap G <b> 1 is provided between the counter electrode 5 and the base end portion 33 of the actuator body 3. The counter electrode 5 is provided for each actuator body 3. The counter electrode 5 is formed of the second silicon layer 230. The counter electrode 5 is formed integrally with a portion formed of the second silicon layer 230 in the base portion 2. However, in the second silicon layer 230 of the base portion 2, grooves 234, 234,... For separating the four counter electrodes 5, 5,. The groove 234 reaches the oxide film layer 220. Thus, the four counter electrodes 5, 5,... Are electrically insulated from each other. The gap G1 is formed by removing the oxide film layer 220.

  As will be described in detail later, the base portion 2 is provided with first and second detection terminals 81 and 82 for detecting the capacitance between the actuator body 3 and the counter electrode 5. Specifically, the first detection terminal 81 is provided on the first silicon layer 210 in the base portion 2. Since the first detection terminal 81 is provided in the first silicon layer 210, it is electrically connected to the actuator body 3. The base portion 2 is formed with a substantially rectangular opening 21 for exposing the second silicon layer 230 to the first silicon layer 210 side. The opening 21 penetrates the first silicon layer 210 and the oxide film layer 220. The second detection terminal 82 is provided on the second silicon layer 230 exposed in the opening 21. Since the second detection terminal 82 is provided in the second silicon layer 230, it is electrically connected to the counter electrode 5.

  Further, a reference terminal 83 is provided on the first silicon layer 210 of the base portion 2 on the side opposite to the first detection terminal 81 with the opening 21 in between. The reference terminal 83 is a terminal for detecting a reference capacitance, which will be described later in detail.

  A gap G <b> 2 is provided between the first silicon layer 210 and the second silicon layer 230 in a portion of the base portion 2 adjacent to the opening 21 and closer to the reference terminal 83 than the opening 21. The gap G2 communicates with the opening 21. The gap G2 is formed by removing the oxide film layer 220.

  Next, the operation of the mirror array 100 configured as described above will be described. The control unit 120 of the mirror array 100 applies a driving voltage to the terminal 43 b of the upper electrode 43 and the lower terminal 41 a of the lower electrode 41. In response to this driving voltage, the piezoelectric layer 42 contracts or expands, and the actuator body 3 tilts upward (on the front surface 31 side) or downward (on the back surface 32 side). More specifically, the mirror 110 can be rotated about the main axis X by tilting the two actuator bodies 3 and 3 connected to the mirror 110 in the same direction. At this time, the rotation direction of the mirror 110 around the main axis X can be switched depending on whether the two actuator bodies 3 and 3 are tilted upward or downward. On the other hand, the mirror 110 can be rotated around the sub-axis Y by tilting the two actuator bodies 3 and 3 in opposite directions. At this time, the rotation direction of the mirror 110 around the secondary axis Y can be switched by switching the actuator body 3 tilted upward and the actuator body 3 tilted downward.

  Further, the control unit 120 detects the electrostatic capacitance between the actuator body 3 and the counter electrode 5 via the first and second detection terminals 81 and 82 provided on the base unit 2, so that the actuator body 3 displacement, that is, the amount of tilting is detected. That is, when the actuator body 3 tilts, the size of the gap G1 between the actuator body 3 and the counter electrode 5 changes. Thereby, since the electrostatic capacitance between the actuator body 3 and the counter electrode 5 changes, the tilt amount of the actuator body 3 can be detected by detecting the electrostatic capacity. Then, the control unit 120 adjusts the drive voltage based on the capacitance between the first and second detection terminals 81 and 82 so that the tilt amount of the actuator body 3 becomes a desired value. By doing so, the amount of tilting of the actuator body 3 can be stably controlled even if a characteristic change occurs in the piezoelectric element 4.

  When detecting the capacitance, the control unit 120 uses the reference terminal 83 and the second detection terminal 82 to connect the first silicon layer 210 and the second silicon layer with the gap G2 in the base unit 2 interposed therebetween. The electrostatic capacity between 230 is detected. Since the gap G2 should not change even when the actuator body 3 is operated, the capacitance of the gap G2 can be used as a reference capacitance. That is, since the amount of change in the capacitance in the gap G1 before and after the tilting of the actuator body 3 is very small, it is difficult to obtain a large amplification in the circuit by itself. However, by providing a reference electrode having the same capacitance, the capacitance before tilting can be canceled out differentially, and only the change before and after tilting the capacitance can be greatly amplified. Thereby, the change of the electrostatic capacitance resulting from the tilting of the actuator body 3 can be detected with high accuracy. Note that the gap G2 is not necessarily provided, and the capacitance in the portion where the oxide film layer 220 exists may be used for reference. However, in this case, it is necessary to match the value of the reference capacitance with the capacitance in the gap G1 before tilting.

  Regarding the control method when the rotation angle of the mirror 110 is kept constant, in addition to the feedback control that keeps the capacitance of the detection unit constant, the host system monitors the reflected light from the mirror and the light quantity is constant. A method of applying feedback to the arithmetic device may be used. Alternatively, both can be used in combination.

  The control unit 120 can be configured by an arithmetic device such as a CPU. The control unit 120 determines a voltage value of a drive voltage for rotating the mirror 110 to a desired rotation angle with reference to a parameter stored in a storage device accessible from the arithmetic device. The parameter represents the rotation angle of the mirror for each drive voltage, and is stored in the storage device in the form of table data or in the form of approximate curve coefficients.

  The parameter stored in the storage device may include a displacement caused by the surrounding environment such as a temperature change. In addition, since the actuator warp generated by the piezoelectric element is not constant when no voltage is applied, an offset voltage for matching the actuator warp to the reference plane may be stored in the storage device. These parameters are usually required for each mirror, but may be represented by one.

  The voltage application instruction by the CPU as described above may be sequentially performed on each mirror 110 in order to simplify the circuit.

  Next, a method for manufacturing the mirror array 100 will be described.

  First, an SOI substrate 200 is prepared.

  Subsequently, the portion of the oxide film layer 220 that becomes the gaps G1 and G2 is removed by sacrificial layer etching. At this time, a plurality of through holes are formed in the first silicon layer 210, and sacrificial layer etching is performed through the through holes. Further, with respect to the portion that becomes the gap G1, not all the oxide film layer 220 is removed, but the oxide film layer 220 partially remains at the end of the actuator body 3 on the tip side of the portion that becomes the counter electrode 5. Keep it.

Thereafter, an SiO ₂ film, a Pt / Ti film 250, a PZT film, and an Au / Ti film are sequentially formed on the surface of the first silicon layer 210, and then formed into a predetermined shape by etching. Thus, the piezoelectric element 4 is formed on the surface of the first silicon layer 210. The through hole used in the sacrifice layer etching is filled by forming a SiO ₂ film or the like.

  Subsequently, the first silicon layer 210 is etched to form the base 2, the actuator bodies 3, 3,..., The mirrors 110 and 110, the first hinges 6, 6,. Thereafter, the oxide film layer 220 exposed in the opening 21 of the base portion 2 is removed by etching.

  Next, the second silicon layer 230 is etched to form the counter electrode 5. At this time, since the oxide film layer 220 remains at the end of the counter electrode 5 adjacent to the portion to be removed in this step (that is, the end on the front end side of the actuator body 3), the etching gas Is prevented from flowing into the gap G1. This prevents unnecessary processing of the first and second silicon layers 210 and 230 that form the gap G1.

  .., The mirrors 110 and 110, the first hinges 6, 6,... And the oxide film layer 220 on the back side of the second hinges 7 and 7 are removed by etching. At this time, the oxide film layer 220 remaining at the end of the actuator body 3 in the portion that becomes the counter electrode 5 is also removed, and a complete gap G1 is formed.

  Next, an Au / Ti film is formed to form the mirror surface on the surface of the mirror 110, the balance weight on the back surface of the mirror 110, and the first detection terminal 81, the second detection terminal 82, and the reference terminal 83 in the base portion 2. To do.

  Thus, the mirror array 100 is manufactured.

  Next, the detailed shape of the first hinge 6 will be described. FIG. 5 shows a plan view of the first hinge 6.

  The first hinge 6 has a first zigzag folding part 61 provided on the mirror side and a second zigzag folding part 62 provided on the actuator side. The first zigzag folding part 61 and the second zigzag folding part 62 are continuously formed by one line.

  In the first zigzag folding part 61, linear line parts 61 a that extend in a straight line and bent parts 61 b that bend so as to be folded back are alternately connected, and are bent in zigzag form as a whole. One end of the first zigzag folding portion 61 is connected to an end portion on the outer side in the main axis X direction (width direction) of the mirror 110. The linear portions 61a, 61a,... Extend in the main axis X direction, and are arranged parallel to each other and at equal intervals. The bent portions 61b, 61b, ... are located on the inner side and the outer side in the main axis X direction. In other words, the first zigzag folding part 61 extends in the sub-axis Y direction (longitudinal direction) while meandering in the main axis X direction. The first zigzag folding part 61 starts with a linear part 61a extending inward in the main axis X direction from the mirror 110, and through the bent part 61b, a linear part 61a extending outward in the main axis X direction and a linear part extending inward in the main axis X direction. 61a is repeated, and finally ends with a linear portion 61a extending inward in the main axis X direction.

  In the second zigzag folding part 62, the linearly extending linear part 62a and the bending part 62b bent so as to be folded back are alternately connected, and the second zigzag folding part 62 is bent in zigzag as a whole. One end of the second zigzag folding part 62 is connected to the outer end of the actuator 1 in the main axis X direction. The linear portions 62a, 62a,... Extend in the sub-axis Y direction, and are arranged in parallel to each other at equal intervals. The bent portions 62b, 62b,... Are located on the actuator side and the mirror side in the sub-axis Y direction. In other words, the second zigzag folding part 62 extends in the main axis X direction while meandering in the sub axis Y direction. The second zigzag folding part 62 starts from the linear part 62a extending to the mirror side from the actuator 1, and repeats the linear part 62a extending to the actuator side and the linear part 62a extending to the mirror side via the bent part 62b. Ends with a line portion 62a extending to the mirror side. A linear portion 62 a extending to the last mirror side is connected to the first zigzag folding portion 61.

  The two first hinges 6, 6 connected to one mirror 110 are configured to be line symmetric with respect to the sub-axis Y.

  According to the 1st hinge 6 comprised in this way, while being able to transmit the driving force (displacement) of the actuator 1 to the mirror 110 efficiently, it can prevent that rotation of the mirror 110 is prevented. it can.

  That is, in order to efficiently transmit the driving force of the actuator 1 to the mirror 110, the first hinge 6 may not have a bending rigidity around the main axis X that is too small or too large. If the bending rigidity around the main axis X is too small, the first hinge 6 absorbs the driving force of the actuator 1 and the driving force transmitted to the mirror 110 decreases. On the other hand, if the bending rigidity around the main axis X is too large, the actuator 1 is prevented from tilting. That is, for example, when the tip of the actuator body 3 tilts so as to sink downward, the mirror 110 rotates so that the actuator side sinks. That is, the actuator 1 and the mirror 110 are bent at the first hinge 6 as a whole. Here, if the bending rigidity of the first hinge is large, it is difficult to bend at the first hinge 6. As a result, the actuator 1 is prevented from tilting by the resistance of the first hinge 6 and the mirror 110.

  On the other hand, in the present embodiment, the first hinge 6 includes a first zigzag folded portion 61 including a plurality of linear portions 61a, 61a,... Extending in the main axis X direction, and a plurality of linear portions extending in the sub-axis Y direction. The second zigzag folding part 62 including 62a, 62a,. Since the linear portions 61a, 61a,... Of the first zigzag folding portion 61 extend in the main axis X direction, torsional deformation around the main axis X is likely to occur. That is, the first zigzag folding part 61 has a small bending rigidity around the main axis X. On the other hand, since the linear portions 62a, 62a,. That is, the second zigzag folding part 62 has a large bending rigidity around the main axis X. Thus, the first hinge 6 adjusts the bending rigidity around the main axis X by combining the first zigzag folding part 61 having a small bending rigidity around the main axis X and the second zigzag folding part 62 having a large bending rigidity around the main axis X. As a result, moderate bending rigidity can be realized as a whole.

  In order not to prevent the rotation of the mirror 110, it is preferable that the first hinge 6 has a small bending rigidity around the sub-axis Y. That is, when the mirror 110 is rotated around the sub-axis Y, the two actuators 1 and 1 simply tilt up and down while being parallel to the sub-axis Y, whereas the mirror 110 is It rotates around the axis Y. Therefore, the first hinge 6 must be twisted around the sub-axis Y. If the bending rigidity of the first hinge 6 about the sub-axis Y is large, even if the two actuators 1 and 1 tilt up and down, the first hinges 6 and 6 become resistances and the mirror 110 rotates about the sub-axis Y. It will prevent the rotation.

  On the other hand, in this embodiment, the 1st hinge 6 has the 2nd zigzag folding part 62 containing several linear part 62a, 62a, ... extended in the sub-axis Y direction. Since the linear portions 62a, 62a,... Of the second zigzag folding portion 62 extend in the sub-axis Y direction, torsional deformation around the sub-axis Y is likely to occur. That is, the second zigzag folding part 62 has a small bending rigidity around the sub-axis Y. Thus, the first hinge 6 has the second zigzag folding part 62 having a small bending rigidity around the sub-axis Y, thereby reducing the bending rigidity around the sub-axis Y as a whole.

  Next, the detailed shape of the second hinge 7 will be described. FIG. 6 shows a plan view of the second hinge 7.

  The second hinge 7 is formed by a single filament. The second hinge 7 is connected to the mirror 110 at one end, extends from there in a counterclockwise spiral toward the center of the spiral, turns back at the center of the spiral, and then spirals in a clockwise spiral from there. It extends toward the outside, and the other end is connected to the base portion 2. Specifically, in the second hinge 7, horizontal line portions 71a extending in the main axis X direction and vertical line portions 71b extending in the sub-axis Y direction are alternately connected to form a spiral shape as a whole. One end and the other end of the second hinge 7 are located on the auxiliary axis Y. When the second hinge 7 is divided into two by the sub-axis Y, the part on one side and the part on the other side with respect to the sub-axis Y have a point-symmetric shape with respect to the center of the spiral.

  Since the second hinge 7 configured as described above has a spiral shape, the rotation of the mirror 110 around the main axis X and the rotation around the sub-axis Y can be prevented. That is, by forming the second hinge 7 in a spiral shape, the second hinge 7 has a plurality of horizontal line portions 71a, 71a,... Having a certain length and a plurality having a certain length. Of the vertical strips 71b, 71b,. Since the horizontal strips 71a, 71a,... Extend in the main axis X direction, the torsional rigidity around the main axis X is small. Moreover, since the vertical strips 71b, 71b,... Extend in the secondary axis Y direction, the torsional rigidity around the secondary axis Y is small. That is, the second hinge 7 is easy to rotate both about the main axis X and about the sub-axis Y. As a result, the rotation of the mirror 110 around the main axis X and the rotation around the sub-axis Y are not hindered.

  Further, the horizontal strips 71a, 71a,... Pass through the center of the spiral and are evenly arranged on both sides of the main shaft X, and the vertical strips 71b, 71b,. Are evenly arranged. Therefore, the deformation of the second hinge 7 when the mirror 110 is deformed around the main axis X and the sub axis Y is uniform with respect to the main axis X and the sub axis Y.

<simulation>
Next, a simulation of the rotation angle of the mirror 110 when the shape of the first hinge 6 is changed will be described. Note that the models used in the following simulation are merely examples, and the present invention is not limited to these.

FIG. 7 shows a plan view of the basic model used in the simulation. In the simulation, a model as shown in FIG. 7 was used. The actuator body 3, the first hinge 6, the mirror 110, and the second hinge 7 are made of silicon having a thickness of 7.5 μm, and the entire surface of the actuator body 3 (the hatched area in FIG. 7) has a thickness. 3 μm PZT is laminated. The analysis tool used for the simulation was ANSYS Workbench Mechanical 13.0. As material properties, silicon was linear isotropic, Young's modulus was 170 GPa, density was 2330 kg / m ³ , and Poisson's ratio was 0.3. PZT is linear isotropic, Young's modulus is 60 GPa, density is 8500 kg / m ³ , Poisson's ratio is 0.3, and piezoelectric constant d ₃₁ is 1.15 × 10 ⁻¹⁰ m / V.

  Each actuator body 3 is rectangular and has a length (dimension in the secondary axis Y direction) of 3000 μm and a width (dimension in the principal axis X direction) of 47.5 μm. The two actuator bodies 3, 3 are integrated at the base end, and the base end of the integrated part is fixedly restrained. The integrated part has a length of 80 μm and a width of 100 μm. A gap of 5 μm was provided between the two actuator bodies 3 and 3.

  The mirror 110 is rectangular and has a length of 400 μm and a width of 100 μm.

  The second hinge 7 has a spiral shape as described above, and extends approximately three and a half halves toward the center of the vortex, and then turns back and extends approximately three and a half halves toward the outside of the spiral. The distance in the secondary axis Y direction between the second hinge 7 and the base portion 2 is 140 μm. The total width of the second hinge 7 in the principal axis X direction is 72 μm. Moreover, the length of the vertical line part 71b which exists in the center of the spiral of the 2nd hinge 7 is 56 micrometers. The width of the filaments was 2 μm, and the spacing between the filaments was 3 μm. The mirror-side end and the base-side end of the second hinge 7 extend in the sub-axis Y direction by 5 μm. The end portion of the second hinge 7 on the base portion side is fixedly restrained.

  In such a model, the rotation angle of the mirror 110 was obtained by changing the shape of the first hinge 6 in various ways. As for the rotation angle of the mirror 110 about the main axis X, the rotation angle when a voltage of 5 V was applied to the two actuators 1 and 1 was obtained. As for the rotation angle of the mirror 110 about the sub-axis Y, the rotation angle when a voltage of 5 V was applied to one actuator 1 and −5 V was applied to the other actuator 1 was obtained.

-Model 0-
In FIG. 8, the top view of the model 0 of the 1st hinge 6 is shown. This model 0 is a model in which the first hinge 6 is configured by only the first zigzag folding portion 61. The distance between the actuators 1, 1 and the mirror 110 in the sub-axis Y direction is 123 μm, and 24 linear portions 61 a, 61 a,... In this model 0, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 0.74 degrees.

-Model 1-
In FIG. 9, the top view of the model 1 of the 1st hinge 6 is shown. The model 1 has the same configuration as the first hinge 6 shown in FIG. Specifically, in the model 1, the first hinge 6 includes a first zigzag folding portion 61 and a second zigzag folding portion 62. The first zigzag folding part 61 is arranged on the mirror side, and the second zigzag folding part 62 is arranged on the actuator side. The first zigzag fold 61 is connected to the outer end of the mirror 110 in the main axis X direction. The second zigzag fold 62 is connected to the outer end of the actuator 1 in the main axis X direction. The distance in the sub-axis Y direction between the actuators 1 and 1 and the mirror 110 is 128 μm. A total of 11 line portions 61a, 61a,... Of the first zigzag folding portion 61 are provided, and are parallel to each other and extend in the main axis X direction. A total of nine line portions 62a, 62a,... Of the second zigzag folding portion 62 are provided and extend in parallel to each other and in the sub-axis Y direction. In the second zigzag folding part 62 from the actuator 1 to the first zigzag folding part 61, the linear part 62a on the most actuator 1 side is located on the outermost side in the main axis X direction. And the linear part 62a by the side of the most folded part is located in the innermost part of the main-axis X direction. In this model 1, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 2.65 degrees. The distance in the sub-axis Y direction between the actuators 1 and 1 and the mirror 110 is 128 μm in the following models 2 to 7 as well.

-Model 2-
In FIG. 10, the top view of the model 2 of the 1st hinge 6 is shown. The basic configuration of the model 2 is the same as that of the model 1, and the number of the linear portions 62a of the second zigzag folding portion 62 is different from the model 1. Specifically, in the model 2, only seven line portions 62a of the second zigzag folding portion 62 are provided from the outside in the main axis X direction toward the inside. Note that the number of the bent portions 62b is reduced as compared with the model 1 in accordance with the number of the linear portions 62a. In this model 2, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 2.55 degrees.

-Model 3-
In FIG. 11, the top view of the model 3 of the 1st hinge 6 is shown. The basic configuration of the model 3 is the same as that of the model 2, and the extending direction of the linear portion 62a of the second zigzag folding portion 62 is different from the model 2. Specifically, in the model 3, the linear portion 62a of the second zigzag folding portion 62 extends in a direction inclined with respect to the sub-axis Y. The linear portion 62a is inclined so that the actuator side is positioned on the inner side in the main axis X direction than the mirror side. However, the linear portion 62a located at the outermost position in the main axis X direction extends in the sub axis Y direction without being inclined. An angle (hereinafter also referred to as an inclination angle) θy formed by the linear portion 62a and the sub-axis Y is 13 degrees. As shown in FIG. 12, the inclined linear portion 62 a is decomposed into the main-axis X-direction component 62 ax and the sub-axis Y-direction component 62 ay so that the sub-axis Y-direction component 62 ay becomes larger. It is inclined. That is, the inclination angle θy with respect to the sub-axis Y of the linear portion 62a is less than 45 degrees. In this model 3, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 2.66 degrees.

-Model 4-
In FIG. 13, the top view of the model 4 of the 1st hinge 6 is shown. The basic configuration of the model 4 is the same as that of the model 2 described above, and the number of the linear portions 61a of the first zigzag folding portion 61 and the connection of the second zigzag folding portion 62 to the actuator 1 and the first zigzag folding portion 61 are made. Is different from Model 2. Specifically, the first zigzag folding part 61 is provided with ten line parts 61a, 61a,..., And the actuator-side line part 61a ends from the inner side toward the outer side in the main axis X direction. ing. In the second zigzag folding part 62 from the actuator 1 to the first zigzag folding part 61, the linear part 62a closest to the actuator 1 is located at the innermost position in the main axis X direction. That is, the second zigzag folding part 62 extends from the end on the outer side of the main shaft X direction of the actuator 1 in the sub-axis Y direction, immediately bends inward in the main shaft X direction, and extends from the innermost side to the outer side in the main shaft X direction. It extends while meandering. The outermost linear portion 62 a in the main axis X direction is connected to the first zigzag folding portion 61. In this model 4, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 2.51 degrees.

-Model 5-
In FIG. 14, the top view of the model 5 of the 1st hinge 6 is shown. The basic configuration of the model 5 is the same as that of the model 4, and the extending direction of the linear portion 62a of the second zigzag folding portion 62 is different from the model 4. Specifically, in the model 5, the line portions 62a of the second zigzag folding portion 62 extend in a direction inclined with respect to the sub-axis Y. The linear portion 62a is inclined so that the mirror side is positioned on the inner side in the main axis X direction than the actuator side. However, the linear portion 62a located at the outermost position in the main axis X direction extends in the sub axis Y direction without being inclined. An angle (hereinafter also referred to as an inclination angle with respect to the sub-axis Y) θy formed by the linear portion 62a and the sub-axis Y is 13 degrees. The linear portion 62a inclined in this way is inclined so that the sub-axis Y-direction component 62ay becomes larger when it is decomposed into the main-axis X-direction component 62ax and the sub-axis Y-direction component 62ay. That is, the inclination angle θy of the linear portion 62a with respect to the sub-axis Y direction is less than 45 degrees. In this model 5, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 1.40 degrees.

-Model 6
FIG. 15 shows a plan view of the model 6 of the first hinge 6. The basic configuration of the model 6 is the same as that of the model 3, and the shape of the first hinge 6 of the model 3 is inverted with respect to a straight line parallel to the main axis X (that is, the first hinge 6 in FIG. This is different from the model 3 in that the shape is reversed left and right. That is, in the first hinge 6 of the model 6, the first zigzag folding part 61 is provided on the actuator side, and the second zigzag folding part 62 is provided on the mirror side. The linear portion 62 a of the second zigzag folding portion 62 extends in a direction inclined with respect to the sub-axis Y. The linear portion 62a is inclined so that the mirror side is positioned on the inner side in the main axis X direction than the actuator side. The inclination angle θy of the linear portion 62a with respect to the minor axis Y is 13 degrees. In this model 6, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 2.53 degrees.

-Model 7-
FIG. 16 shows a plan view of the model 7 of the first hinge 6. The basic configuration of the model 7 is the same as that of the model 5 described above, and the first hinge 6 of the model 5 is inverted with respect to a straight line parallel to the main axis X (that is, the first hinge 6 in FIG. The shape is reversed left and right). That is, in the first hinge 6 of the model 7, the first zigzag folding part 61 is provided on the actuator side, and the second zigzag folding part 62 is provided on the mirror side. The linear portions 62a, 62a,... Of the second zigzag folding portion 62 extend in a direction inclined with respect to the sub-axis Y. The linear portion 62a is inclined so that the actuator side is positioned on the inner side in the main axis X direction than the mirror side. The inclination angle θy of the linear portion 62a with respect to the minor axis Y is 13 degrees. In this model 7, the rotation angle when the mirror 110 was rotated about the sub-axis Y was 1.59 degrees.

-Summary-
As described above, when the models 0 to 7 are compared, the rotation angle around the sub-axis Y is 0.74 degrees for the model 0, and 1.40 to 2.66 degrees for the models 1 to 7. That is, it can be seen that the rotation angle around the sub-axis Y is increased by including the first zigzag fold 61 and the second zigzag fold 62 in the first hinge 6. It can also be seen that the rotation angle around the sub-axis Y increases even when the linear portion 62a is inclined with respect to the sub-axis Y in the second zigzag folding section 62. Further, among the models 1 to 7, the models 1 to 4 and 6 have a significantly increased rotation angle around the sub-axis Y compared to the models 5 and 7.

-Model 8-
FIG. 17 shows a plan view of the model 8 of the first hinge 6. The basic configuration of the model 8 is the same as that of the model 2, and the dimension of the first zigzag folding portion 61 in the sub-axis Y direction is different from that of the model 2. Specifically, the distance in the sub-axis Y direction between the actuators 1 and 1 and the mirror 110 is 188 μm. The distance in the sub-axis Y direction from the actuator 1 to the mirror-side end of the second zigzag folding part 62 is 75 μm. Both end portions of the first zigzag folding portion 61 are vertical line portions 61c and 61c extending in the sub-axis Y direction, and are connected to the end of the second zigzag folding portion 62 and the mirror 110, respectively. Each vertical line 61c has a length of 33 μm. The length of the first zigzag folding part 61 in the sub-axis Y direction is 113 μm. In this model 8, the rotation angle when the mirror 110 is rotated about the main axis X is 5.48 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 2 It was 80 degrees. The distance in the sub-axis Y direction between the actuators 1 and 1 and the mirror 110 is 188 μm in the following models 9 to 13 as well.

-Model 9-
FIG. 18 shows a plan view of the model 9 of the first hinge 6. The basic configuration of the model 9 is the same as that of the model 8, and the extending direction of the linear portion 61a of the first zigzag folding portion 61 is different from the model 8. Specifically, in the model 9, the linear portion 61 a of the first zigzag folding portion 61 extends in a direction inclined with respect to the main axis X. The linear portion 61a is inclined so that the inner side in the main axis X direction is located on the mirror side than the outer side in the main axis X direction. An angle (hereinafter also referred to as an inclination angle with respect to the main axis X) θx formed by the linear portion 61a and the main axis X is 30 degrees. As shown in FIG. 19, the inclined linear portion 61a is inclined so that the main axis X direction component 61ax becomes larger when the main axis X direction component 61ax is decomposed into the main axis X direction component 61ax and the auxiliary axis Y direction component 61ay. doing. That is, the inclination angle θx with respect to the main axis X of the linear portion 61a is less than 45 degrees. Although the dimension in the sub-axis Y direction of the first zigzag folding part 61 as a whole is the same as that of the model 8, the length of the vertical line part 61c is different from that of the model 8. In the model 9, the vertical line 61c is different between the second zigzag folding part side and the mirror side, and the length of the vertical line 61c on the second zigzag folding part side is 20 μm. In this model 9, the rotation angle when the mirror 110 is rotated about the main axis X is 5.13 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 3 It was 0.00 degrees.

-Model 10-
In FIG. 20, the top view of the model 10 of the 1st hinge 6 is shown. The basic configuration of the model 10 is the same as that of the model 9, and the inclination direction of the linear portion 61a of the first zigzag folding portion 61 is different from that of the model 9. Specifically, in the model 10, the linear portion 61a of the first zigzag folding portion 61 is inclined so that the inner side in the main axis X direction is located on the actuator side than the outer side in the main axis X direction. The inclination angle θx of the linear portion 61a with respect to the main axis X is 30 degrees. The inclined linear portion 61a is inclined such that the main axis X-direction component 61ax is larger when it is decomposed into the main axis X-direction component 61ax and the sub-axis Y-direction component 61ay. The length of the vertical stripe 61c on the mirror side is 20 μm. In this model 10, the rotation angle when the mirror 110 is rotated about the main axis X is 5.13 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 2 It was .73 degrees.

-Model 11-
FIG. 21 shows a plan view of the model 11 of the first hinge 6. The basic structure of the model 11 is the same as that of the model 8, and the shape of the first hinge 6 of the model 8 is inverted with respect to a straight line parallel to the main axis X (that is, the first hinge 6 in FIG. It is different from the model 8 in that the shape is reversed left and right. Specifically, in the first hinge 6 of the model 11, the first zigzag folding part 61 is provided on the actuator side, and the second zigzag folding part 62 is provided on the mirror side. In this model 11, the rotation angle when the mirror 110 is rotated about the main axis X is 5.12 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 2 It was .83 degrees.

-Model 12-
FIG. 22 shows a plan view of the model 12 of the first hinge 6. The basic configuration of the model 12 is the same as that of the model 9, and the shape of the first hinge 6 of the model 9 is inverted with respect to a straight line parallel to the main axis X (that is, the first hinge 6 in FIG. It is different from the model 9 in that the shape is reversed left and right. Specifically, in the first hinge 6 of the model 12, the first zigzag folding part 61 is provided on the actuator side, and the second zigzag folding part 62 is provided on the mirror side. The linear portion 61 a of the first zigzag folding portion 61 extends in a direction inclined with respect to the main axis X. The linear portion 61a is inclined so that the inner side in the main axis X direction is located on the actuator side than the outer side in the main axis X direction. The inclination angle θx with respect to the linear portion 61a and the main axis X is 30 degrees. In this model 12, the rotation angle when the mirror 110 is rotated about the main axis X is 4.88 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 3 It was 49 degrees.

-Model 13-
FIG. 23 shows a plan view of the model 13 of the first hinge 6. The basic configuration of the model 13 is the same as that of the model 10 and is different from the model 10 in that the first hinge 6 of the model 10 has a shape inverted with respect to a straight line parallel to the main axis X. Specifically, in the first hinge 6 of the model 13, the first zigzag folding part 61 is provided on the actuator side, and the second zigzag folding part 62 is provided on the mirror side. The linear portion 61 a of the first zigzag folding portion 61 extends in a direction inclined with respect to the main axis X. The linear portion 61a is inclined so that the inner side in the main axis X direction is located on the mirror side than the outer side in the main axis X direction. The inclination angle θx with respect to the linear portion 61a and the main axis X is 30 degrees. In this model 13, the rotation angle when the mirror 110 is rotated about the main axis X is 4.87 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 2 It was 31 degrees.

-Summary-
As described above, when the model 8 and the model 11 are compared, in the configuration in which the linear portion 61a of the first zigzag folding portion 61 extends in the main axis X direction and the linear streak portion 62a of the second zigzag folding portion 62 extends in the sub-axis Y direction. It can be seen that even if the positions of the first zigzag fold 61 and the second zigzag fold 62 are switched, the rotation angles about the main axis X and the sub axis Y do not change significantly. That is, even if the first zigzag fold 61 and the second zigzag fold 62 are located on either the actuator side or the mirror side, there is no significant effect on the rotation angles around the main axis X and the sub axis Y.

  Further, when comparing the model 8 in which the linear portion 61a of the first zigzag folding portion 61 extends in the main axis X direction and the models 9 and 10 in which the linear portion 61a of the first zigzag folding portion 61 is inclined with respect to the main axis X direction, It can be seen that both models have large rotation angles around the main axis X and the sub-axis Y. More specifically, it can be seen that the rotation angle around the main axis X is the largest in the model 8, while the rotation angle around the sub-axis Y is the largest in the model 9 and the smallest in the model 10. However, these differences are slight.

  Furthermore, when comparing the model 11 in which the linear portion 61a of the first zigzag folding portion 61 extends in the main axis X direction and the models 12 and 13 in which the linear portion 61a of the first zigzag folding portion 61 is inclined with respect to the main axis X direction, It can be seen that both models have large rotation angles around the main axis X and the sub-axis Y. More specifically, it can be seen that the rotation angle around the main axis X is the largest in the model 11, while the rotation angle around the sub-axis Y is the largest in the model 12 and the smallest in the model 13. However, these differences are slight.

-Model 14-
FIG. 24 shows a plan view of the model 14 of the first hinge 6. The basic configuration of the model 14 is the same as that of the model 0, and the number of the linear portions 61a of the first zigzag folding portion 61 is different from that of the model 0. Specifically, the model 14 is a model in which the first hinge 6 is configured by only the first zigzag folding portion 61. The distance between the actuators 1, 1 and the mirror 110 in the sub-axis Y direction is 128 μm, and 16 line portions 61 a, 61 a,... At both ends of the first zigzag folding portion 61, vertical line portions 61c and 61c extending in the sub-axis Y direction are provided. The length of the vertical line portion 61c is 25.5 μm. In this model 14, the rotation angle when the mirror 110 is rotated about the main axis X is 5.73 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 0. It was 87 degrees. Note that the distance in the sub-axis Y direction between the actuators 1 and 1 and the mirror 110 is 128 μm in the following models 15 and 16 as well.

-Model 15-
FIG. 25 shows a plan view of the model 15 of the first hinge 6. The basic configuration of the model 15 is the same as that of the model 14, and the extending direction of the linear portion 61 a of the first zigzag folding portion 61 is different from the model 14. Specifically, in the model 15, the linear portion 61 a of the first zigzag folding portion 61 extends in a direction inclined with respect to the main axis X. The linear portion 61a is inclined so that the inner side in the main axis X direction is located on the mirror side than the outer side in the main axis X direction. The inclination angle θx of the linear portion 61a with respect to the main axis X is 35 degrees. The length of the vertical stripe 61c on the mirror side is 27.5 μm. In this model 15, the rotation angle when the mirror 110 is rotated about the main axis X is 4.60 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 0. It was 58 degrees.

-Model 16-
FIG. 26 shows a plan view of the model 16 of the first hinge 6. The basic configuration of the model 16 is the same as that of the model 15, and the inclination direction of the linear portion 61 a of the first zigzag folding portion 61 is different from that of the model 15. Specifically, in the model 16, the linear portion 61 a of the first zigzag folding portion 61 extends in a direction inclined with respect to the main axis X. The linear portion 61a is inclined so that the inner side in the main axis X direction is located on the actuator side than the outer side in the main axis X direction. The inclination angle θx of the linear portion 61a with respect to the main axis X is 35 degrees. The length of the vertical line 61c on the actuator side is 27.5 μm. In this model 16, the rotation angle when the mirror 110 is rotated about the main axis X is 4.59 degrees, and the rotation angle when the mirror 110 is rotated about the sub-axis Y is 1 It was 30 degrees.

-Summary-
When comparing the model 14 with the models 15 and 16, when the linear portion 61a is tilted with respect to the main axis X, the rotation angle around the main axis X becomes smaller and the rotation angle around the sub-axis Y becomes smaller in the inclination direction. It can be seen that it can be both large and small. In the model 2 in which the dimension in the sub-axis Y direction between the actuator 1 and the mirror 110 is the same and the first hinge 6 is composed of the first zigzag folding part 61 and the second zigzag folding part 62, the mirror 110 is the main axis. The rotation angle when rotated about X was 5.64 degrees, and the rotation angle when the mirror 110 was rotated about the sub-axis Y was 2.55 degrees. From this result, the rotation angle around the sub-axis Y is greater when the first hinge 6 includes the first zigzag fold 61 and the second zigzag fold 62 as compared to simply tilting the filament 61a. It can be seen that it can be greatly increased. Furthermore, it can be seen that even with such a configuration, the rotation angle around the main axis X is not significantly reduced.

  Therefore, according to the present embodiment, the mirror array 100 drives the mirror 110 by being connected to the base unit 2, the plurality of mirrors 110, 110,... Supported by the base unit 2, and the mirror 110. A plurality of actuators 1 and 1 are provided, and the mirror 110 is rotated about a main axis X and a sub-axis Y that are orthogonal to each other. The actuator 1 includes an actuator main body 3 extending in the sub-axis Y direction and a piezoelectric element 4 stacked on the surface of the actuator main body 3, and the actuator main body 3 is expanded and contracted by expanding and contracting the piezoelectric element 4. Each mirror 110 is provided with the two actuators 1, 1 arranged on both sides of the auxiliary shaft Y on only one side with respect to the main shaft X.

  According to this configuration, two actuators 1 and 1 are provided for one mirror 110. That is, the number of actuators per mirror is reduced compared to the mirror device described in Patent Document 1. Therefore, the configuration of the mirror array 100 can be simplified.

  Even if the actuator 1 has a simple configuration in which the actuator 1 is provided only on one side with respect to the main axis X of the mirror 110, the actuator 1 is piezoelectrically driven and the two actuators 1 and 1 are arranged side by side with the sub-axis Y in between. Thus, the mirror 110 can be rotated about both the main axis X and the sub-axis Y.

  That is, in the configuration in which the actuator body 3 and the piezoelectric element 4 are laminated, the actuator body 3 can be tilted to the opposite side of the piezoelectric element 4 by stretching the piezoelectric element 4, while the piezoelectric element 4 contracts. By doing so, the actuator body 3 can be tilted to the piezoelectric element side. Therefore, even if the actuator 1 is provided only on one side with respect to the main axis X of the mirror 110, the mirror 110 can be rotated in any direction around the main axis X.

  Further, since the two actuators 1 and 1 provided for each mirror 110 are arranged with the secondary axis Y in between, the mirror 110 is rotated about the secondary axis Y by tilting one actuator 1. Can do. At this time, the rotation angle of the mirror 110 around the secondary axis Y can be increased by tilting the other actuator 1 to the side opposite to the one actuator 1. Further, when the mirror 110 is rotated around the sub-axis Y, the sub-axis Y can be prevented from tilting.

  Further, the two actuators 1 and 1 are within the dimensions of the mirror 110 in the main axis X direction in the main axis X direction. That is, the dimension of the mirror device including the two actuators 1 and 1 and the mirror 110 in the main axis X direction can be suppressed. As a result, even if the mirror array 100 has a plurality of mirrors 110, 110,..., The mirror 110 can be arranged in a compact manner, and the mirror array 100 can be downsized. .

  In the mirror array 100, each actuator 1 is connected to the mirror 110 via the first hinge 6, and the mirror 110 is supported by the base portion 2 via the second hinge 7. The first hinge 6 is bent in a zigzag shape, and includes a first zigzag fold portion 61 including a plurality of parallel line portions 61a, 61a,... And a second zigzag fold part 62 including a plurality of striate parts 62a, 62a,... Extending in a direction different from the striated line part 61a, and the sliver part 61a of the first zigzag fold part 61 extends in the main axis X direction. When the component 61ax and the component 61ay in the sub-axis Y direction are decomposed, the component 61ax in the main axis X direction extends in the direction of increasing, while the linear portion 62a of the second zigzag folded portion 62 is in the main axis X direction. Component 62ax and component 62ay of the auxiliary shaft Y direction when decomposed into components 62ay of the countershaft Y direction is assumed to extend in the direction of increasing the.

  According to this configuration, the first zigzag folding portion 61 has a small bending rigidity around the main axis X. On the other hand, the second zigzag folding part 62 has a small bending rigidity around the sub-axis Y and a large bending rigidity around the main axis X. Therefore, the first hinge 6 can achieve an appropriate bending rigidity as a whole by adjusting the bending rigidity around the main axis X. In addition, the first hinge 6 can reduce the bending rigidity around the secondary axis Y as a whole. As a result, the first hinge 6 can efficiently transmit the driving force (displacement) of the actuator 1 to the mirror 110 and prevent the rotation of the mirror 110 from being hindered.

  Further, in the mirror array 100, the second hinge 7 has a shape that extends spirally from one end toward the center of the spiral, then turns back, extends spirally toward the outside of the spiral, and reaches the other end. I am doing.

  According to this configuration, the second hinge 7 includes the horizontal line portion 71a extending in the main axis X direction and the vertical line portion 71b extending in the sub-axis Y direction. The horizontal filament 71a has a small torsional rigidity around the main axis X. Further, the vertical line strip portion 71b has a small torsional rigidity around the sub-axis Y. Therefore, the second hinge 7 is easy to rotate about the main axis X and the sub axis Y, so that the rotation of the mirror 110 about the main axis X and the rotation about the sub axis Y are not hindered. be able to. In addition, since the second hinge 7 is formed in a spiral shape, compared with a configuration in which the second hinge 7 is formed in a zigzag manner like the first hinge 6, there are almost no portions where the filaments are folded back. can do.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the embodiment.

  In the embodiment, the example in which the mirror array 100 is applied to the wavelength selective switch 300 has been described. However, the present invention is not limited to this. The mirror array 100 can be incorporated into various applications.

Moreover, the shape, dimension, and material in the said embodiment are only illustrations, and are not restricted to these. For example, KNN ((K, Na) NbO ₃ ), which is a lead-free piezoelectric material, may be used instead of PZT.

  Moreover, in the said embodiment, although the 1st hinge 6 is employ | adopted for the connection of the actuator 1 and the mirror 110, and the 2nd hinge 7 is employ | adopted for the connection of the mirror 110 and the base part 2, it is not restricted to this. . For example, the second hinge 7 can be used instead of the first hinge 6, and the first hinge 6 can be used instead of the second hinge 7.

  In the mirror array 100, the upper terminal 43b, the first detection terminal 81, and the reference terminal 83 are provided in common for all the actuators 1, 1,..., But may be provided individually. The actuators 1, 1,... May be divided into several groups, and the terminals may be provided for each group.

  Further, even if the first and second hinges 6 and 7 do not have the configuration of the actuator 1, the above-described effects can be obtained. That is, even if two actuators are provided on both sides of the mirror main axis, that is, two actuators are provided, the first or second hinge 6 is connected to each actuator and the mirror. , 7 can be adopted. Furthermore, the first and second hinges 6 and 7 can be employed even for actuators other than the piezoelectric drive type. For example, an electrostatically driven actuator that tilts the actuator body by electrostatic force between the counter electrode, an electromagnetically driven actuator that tilts the actuator body due to the relationship between the magnetic force generated by the coil provided on the actuator body and an external magnetic field, Alternatively, the actuator body may be constituted by members having different linear expansion coefficients, and the actuator body may be tilted by a difference in thermal strain between the two.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a mirror array including a plurality of mirrors and an actuator for driving the mirrors.

DESCRIPTION OF SYMBOLS 100 Mirror array 110 Mirror 300 Wavelength selection switch 1 Actuator 2 Base part 3 Actuator main body 4 Piezoelectric element 6 1st hinge 61 1st zigzag folding part 61a Linear stripe part 62 2nd zigzag folding part 62a Linear line part 7 2nd hinge X Main axis Y Secondary axis

Claims (5)

A mirror comprising a base portion, a plurality of mirrors supported by the base portion, and a plurality of actuators coupled to the mirror to drive the mirror, and rotating the mirror about a main axis and a sub-axis orthogonal to each other An array,
The actuator includes an actuator main body extending in the sub-axis direction and a piezoelectric element stacked on the surface of the actuator main body, and is configured to tilt the actuator main body by expanding and contracting the piezoelectric element. ,
Each of the mirrors is a mirror array in which the two actuators arranged on both sides of the auxiliary shaft are provided only on one side with respect to the main shaft. The mirror array according to claim 1, wherein
The plurality of mirrors are mirror arrays arranged in the principal axis direction. The mirror array according to claim 1 or 2,
Each actuator is connected to the mirror via a first hinge;
The mirror is supported on the base portion via a second hinge,
The first or / and the second hinge is bent in a zigzag manner, and includes a first zigzag fold portion including a plurality of parallel line portions parallel to each other, and a first zigzag fold portion bent in a zigzag shape so as to be parallel to each other and the first zigzag fold portion. A second zigzag folded portion including a plurality of linear portions extending in a direction different from the linear portions of
While the linear portion of the first zigzag folding portion extends in a direction in which the component in the main axis direction increases when decomposed into a component in the main axis direction and a component in the sub axis direction,
The filament array of the second zigzag folding portion is a mirror array that extends in a direction in which the component in the sub-axis direction increases when it is decomposed into a component in the main axis direction and a component in the sub-axis direction. The mirror array according to claim 1 or 2,
Each actuator is connected to the mirror via a first hinge;
The mirror is supported on the base portion via a second hinge,
The first or / and the second hinge extends from one end in a spiral shape toward the center of the spiral, then turns back and extends in a spiral shape toward the outside of the spiral to reach the other end. Mirror array. The mirror array according to claim 3,
The first hinge has the first zigzag fold and the second zigzag fold.
The second hinge is a mirror array in which the second hinge extends from one end in a spiral shape toward the center of the spiral and then is folded back to extend outward from the spiral to the other end.

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