JP2011137911A - Vibrating mirror element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibrating mirror element which accurately reflects light at a mirror part. <P>SOLUTION: The vibrating mirror element 100 includes: a cantilever-shaped driving part 31 which extends in Y-direction in a straight line form and includes an end part 31a formed on Y1 side, an end part 31b formed on Y2 side, and a connection part 31c formed on the end part 31b side; a mirror supporting part 32 which is connected to the connection part 31c of the driving part 31 and so formed to have substantially the same inclination as that of the connection part 31c when the driving part 31 drives; and an X-direction optical scanning part 10 which is turned around the turning center R2 extending in X-direction by being supported by the mirror supporting part 32 so as to have substantially the same inclination as that of the connection part 31c, wherein the turning center R2 is disposed at the position which passes through substantially the center R4 of a straight line (tangential lines C1 and D1) which extends in the Y-direction connecting the end part 31a and the connection part 31c of the diving part 31 when the driving part 31 does not drive. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vibrating mirror element, and more particularly to a vibrating mirror element provided with a drive unit.

  Conventionally, a vibrating mirror element including a drive unit is known (see, for example, Patent Documents 1 and 2).

  In Patent Document 1, a pair of drive units, a mirror unit disposed so as to be sandwiched between the pair of drive units, and rotated by a pair of drive units around a rotation center extending in the X direction, and a pair of An optical deflector is disclosed that includes a drive unit and a support unit disposed so as to surround the mirror unit. One end of each of the pair of drive units is connected to the mirror unit on one side and the other side in the Y direction (a direction orthogonal to the X direction in the same plane). Further, the other end of each of the pair of drive units is fixed by a support unit on the side opposite to the side where the Y-direction mirror unit is disposed. In addition, each of the pair of drive units is arranged in a state in which a plurality of piezoelectric actuators extending in the X direction are arranged in the Y direction, and are continuously connected by being folded back at each end of the plurality of piezoelectric actuators. Has been. Further, the adjacent piezoelectric actuators are configured to be deformed in the reverse direction when a voltage having an opposite phase is applied to the adjacent piezoelectric actuators.

  Further, Patent Document 2 includes a pair of a fixed end portion formed on one side in the X direction and a free end portion formed on the other side in the X direction, and extending linearly along the X direction. A cantilever beam and a folded beam that is arranged so as to be sandwiched between a pair of cantilever beams in the Y direction (a direction orthogonal to the X direction in the same plane) and extends in the same direction as the cantilever beam along the X direction (Supporting portion), a connecting member that connects a free end portion of the pair of cantilever beams and one end portion of the folded beam (the free end portion side of the pair of cantilever beams), and the other end portion (a pair of folded beams) A displacement element is disclosed which is connected to a fixed end portion of the cantilever and includes a rotatable displacement member (mirror portion). In this displacement element, the free end portion of the pair of cantilever beams is displaced to displace the connecting member, whereby the folded beam is inclined and the displacement member is displaced. Further, in the displacement element described in Patent Document 2, the fixed end portions of the pair of cantilevers and the displacement member are arranged so as to be positioned on a straight line extending in the Y direction.

JP 2009-169290 A WO2005 / 059933

  However, the optical deflector described in Patent Document 1 is configured such that adjacent piezoelectric actuators are deformed in the opposite direction, and therefore each inclination generated by the deformation of adjacent piezoelectric actuators is different. it is conceivable that. For this reason, when the pair of drive units are driven, the rotation center of the mirror unit disposed between the pair of drive units is in the vertical direction relative to the position of the rotation center when the pair of drive units is not driven. It is considered to move to. For this reason, since the position of the center of rotation of the mirror unit cannot be maintained constant, the position of the center of rotation of the mirror unit changes according to the driving state of the pair of drive units. However, it is difficult to accurately reflect light.

  Further, in the displacement element described in Patent Document 2, the fixed end portions of the pair of cantilevers and the displacement member are arranged so as to be positioned on a straight line extending in the Y direction. When is displaced, the rotation center of the displacement member is considered to move downward relative to the position of the displacement member when the pair of cantilevers are not displaced. For this reason, since the position of the rotation center of the displacement member cannot be maintained constant, the position of the rotation center of the displacement member changes according to the driving state of the pair of cantilevers. There is a problem that it is difficult to accurately reflect light on the member.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a vibrating mirror element capable of accurately reflecting light at a mirror portion. .

Means for Solving the Problems and Effects of the Invention

  A vibrating mirror element according to one aspect of the present invention includes a fixed end formed on one side in the first direction, a free end formed on the other side in the first direction, and a connection portion formed on the free end side. And is connected to the deformable cantilever-shaped first drive unit and the connection unit of the first drive unit, and when the first drive unit is driven, the connection unit In the second direction orthogonal to the first direction, the mirror support portion is configured to have substantially the same inclination as the inclination in the above, and is supported by the mirror support portion so as to have substantially the same inclination as the inclination in the connection portion. And a mirror portion that rotates about a first rotation center that extends, and the first rotation center connects the fixed end of the first drive portion and the connection portion when the first drive portion is not driven. It is arranged at a position passing through the approximate center of a straight line extending in the direction.

  In the oscillating mirror element according to one aspect of the present invention, as described above, the mirror unit is configured to be supported by the mirror support unit so as to have substantially the same inclination as the inclination in the connection part, thereby providing the first drive unit. When the mirror part is tilted together with the connecting part of the first driving part, the mirror part can be tilted at substantially the same tilt angle as the connecting part. That is, the first rotation center is substantially disposed at a position passing through the tangent line in the connection portion regardless of the driving state and the non-driving state of the first driving portion. Furthermore, in the non-driving state of the first drive unit, the first rotation center is disposed at a position passing through the approximate center of the straight line extending in the first direction connecting the fixed end of the first drive unit and the connection unit, Regardless of the drive state and non-drive state of the first drive unit, the distance between the first rotation center and the connection part of the first drive unit, and the distance between the first rotation center and the fixed end of the first drive unit Can be made substantially the same. Thus, the radius of the connecting portion of the first driving unit is always a straight line (tangent line at the connecting portion) connecting the first rotation center and the connecting portion regardless of the driving state and non-driving state of the first driving unit. And approximately positioned on an arc centered on the first rotation center. As a result, the first rotation center can be disposed at a substantially fixed position regardless of whether the first drive unit is driven or not. Accordingly, the mirror portion can be rotated around the first rotation center so as to have substantially the same inclination as that of the connection portion in a state where the position of the first rotation center does not substantially change. Can be accurately reflected.

  In the oscillating mirror element according to the above aspect, preferably, when the first drive unit is driven while being deformed, the first rotation center is a tangent at the fixed end of the first drive unit and the connection unit of the first drive unit. It is arranged at a position passing through the intersection with the tangent at, and the position of the first rotation center is not substantially changed. If comprised in this way, even if it is a case where it drives, deforming the 1st drive part, the 1st rotation center will be made substantially immovable irrespective of the drive state of the 1st drive part, and the non-drive state. Can be placed in position.

  In the oscillating mirror element according to the above aspect, preferably, when the first drive unit is driven while being deformed, the mirror support unit and the mirror unit have substantially the same inclination as that of the connection part of the first drive unit. It is comprised so that it may be located on the same plane. With this configuration, the mirror unit is rotated around the first rotation center in a state where the inclination of the connection portion of the first drive unit, the inclination of the mirror support unit, and the inclination of the mirror unit are maintained substantially the same. Can be tilted.

  In the vibrating mirror element according to the above aspect, preferably, the first drive unit and the mirror support unit are provided in a pair so as to sandwich the mirror unit on both sides of the mirror unit in the second direction, and the pair of first drive units The fixed ends of the first drive unit are arranged on one side of the mirror unit in the first direction, the free ends of the pair of first drive units are arranged on the other side of the mirror unit in the first direction, and the first rotation center is In a non-driving state of the pair of first drive units, the pair of first drive units are disposed at positions passing through substantially the center of a straight line extending in the first direction connecting the fixed ends of the pair of first drive units and the connection unit. If comprised in this way, each connection of a pair of 1st drive part is in the state which has arrange | positioned the 1st rotation center in the substantially fixed position irrespective of the drive state and non-drive state of a pair of 1st drive part. Since the inclination in the part can be controlled to substantially the same inclination angle, the mirror support part and the mirror part are inclined around the first rotation center at substantially the same inclination angle as each connection part of the pair of first drive parts. Can do. As a result, it is possible to accurately reflect light at the mirror portion. Further, by providing a pair of the first drive unit and the mirror support unit so as to sandwich the mirror unit on both sides of the mirror unit in the second direction, the first mirror unit is supported in a state where the mirror unit is supported from both sides in the second direction. Since it can be rotated around the rotation center, the mirror portion can be rotated more stably.

  In this case, preferably, the pair of first driving units are configured to be driven by applying a voltage, and the pair of first driving units are applied with voltages having substantially the same phase. It is configured. If comprised in this way, a deformation | transformation comparable as the same direction (direction which rotates a mirror part) can be made to raise | generate easily in a pair of 1st drive part.

  In the vibrating mirror element according to the above aspect, preferably, the connection portion of the first drive portion is formed in the vicinity of the free end of the first drive portion, and the mirror support portion is the first in the vicinity of one end portion of the mirror support portion. In the vicinity of the other end of the mirror support portion, it is connected to the connecting portion of the driving portion and is formed to extend linearly along the first direction from the connecting portion toward the fixed end side of the first driving portion. Connected to the mirror section. If comprised in this way, the inclination angle in a connection part can be enlarged more by forming the connection part of a 1st drive part in the free end vicinity which a displacement produces most in a 1st drive part of a cantilever shape. Therefore, a wider angle range in which the mirror portion can be tilted can be secured.

  In the vibrating mirror element according to the above aspect, the length of the first drive unit is preferably greater than the length of the mirror unit in the first direction. If comprised in this way, since the drive force of a 1st drive part can be enlarged by the length of a 1st drive part, the inclination angle in the connection part of a 1st drive part can be enlarged more. . Thereby, the angle range which can incline a mirror part can be ensured more widely.

  In this case, preferably, in the first direction, the length of the first drive unit is at least twice the length of the mirror unit. If comprised in this way, since the drive force of a 1st drive part can be enlarged easily, the inclination angle in the connection part of a 1st drive part can be enlarged easily.

  In the oscillating mirror element according to the above aspect, preferably, the mirror unit includes a mirror and a second driving unit that rotates the mirror around a second rotation center that is orthogonal to the first rotation center in the in-plane direction of the mirror. Including. With this configuration, it is possible to accurately reflect light around the first rotation center in the mirror, and by turning around the first rotation center and turning around the second rotation center, Light can be scanned two-dimensionally.

  In this case, preferably, the first drive unit is configured to rotate the mirror unit around the first rotation center based on the first frequency, and the second drive unit is configured to rotate more than the first frequency. Based on the large second frequency, the mirror is configured to rotate around the second rotation center. With this configuration, it is possible to scan light two-dimensionally in a state where the mirror unit is configured to rotate at a higher frequency around the second rotation center than around the first rotation center.

  In the vibrating mirror element according to the above aspect, the first drive unit, the mirror support unit, and the mirror unit are preferably integrally formed. With this configuration, it is not necessary to separately connect the first drive unit and the mirror support unit and the mirror support unit and the mirror unit, so that the manufacturing process of the vibrating mirror element can be simplified.

It is the perspective view which showed the structure of the vibration mirror element by one Embodiment of this invention. It is the top view which showed the structure of the vibration mirror element by one Embodiment of this invention. It is the side view which showed the structure of the vibration mirror element by one Embodiment of this invention. FIG. 3 is an enlarged sectional view taken along line 1000-1000 of the vibrating mirror element shown in FIG. FIG. 3 is an enlarged cross-sectional view of the oscillating mirror element shown in FIG. 2 taken along line 2000-2000. FIG. 3 is an enlarged cross-sectional view of the oscillating mirror element shown in FIG. 2 taken along line 3000-3000. FIG. 4 is an enlarged cross-sectional view of the oscillating mirror element shown in FIG. 2 taken along line 4000-4000. FIG. 8 is an enlarged cross-sectional view showing the vicinity of a piezoelectric actuator of the vibrating mirror element shown in FIGS. It is the perspective view which showed the state which the vibration mirror element by one Embodiment of this invention inclined with the predetermined | prescribed angle (inclination angle (theta) 1). It is the side view which showed the state in which the vibration mirror element by one Embodiment of this invention inclined with the predetermined | prescribed angle (inclination angle (theta) 1). It is the perspective view which showed the state which the vibration mirror element by one Embodiment of this invention inclined with the predetermined | prescribed angle (inclination angle (theta) 2). It is the side view which showed the state in which the vibration mirror element by one Embodiment of this invention inclined with the predetermined | prescribed angle (inclination angle (theta) 2). It is sectional drawing which showed the manufacturing process of the vibration mirror element by one Embodiment of this invention. It is sectional drawing which showed the manufacturing process of the vibration mirror element by one Embodiment of this invention. It is the top view which showed the structure of the vibration mirror element by the modification of one Embodiment of this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

  First, with reference to FIGS. 1-8, the structure of the vibration mirror element 100 by one Embodiment of this invention is demonstrated.

  As shown in FIGS. 1 to 3, the vibrating mirror element 100 according to an embodiment of the present invention includes an X-direction optical scanning unit 10 for scanning light in the X direction using a mirror 11 described later, and a mirror 11. And a Y-direction optical scanning unit 30 for scanning light in the Y direction orthogonal to the X direction. Further, as shown in FIGS. 4 to 7, the X direction optical scanning unit 10 and the Y direction optical scanning unit 30 are integrally formed on the Si substrate 1 having a common thickness t1 of about 0.1 mm. . The X-direction optical scanning unit 10 is an example of the “mirror unit” in the present invention.

  The oscillating mirror element 100 is incorporated in a device that scans light such as a projector (not shown), scans light in the X direction by the X direction light scanning unit 10, and emits light in the Y direction by the Y direction light scanning unit 30. It is configured to scan. The X-direction optical scanning unit 10 is configured to be resonantly driven at a resonance frequency of about 30 kHz, while the Y-direction optical scanning unit 30 is configured to be non-resonantly driven at a frequency of about 60 Hz. . Here, by configuring the Y-direction optical scanning unit 30 to be non-resonantly driven, there is no change in the resonance frequency due to a change in the temperature around the vibrating mirror element 100. It is possible to drive. The resonance frequency of about 30 kHz is an example of the “second frequency” in the present invention, and the frequency of about 60 Hz is an example of the “first frequency” in the present invention.

As shown in FIGS. 4 and 7, the X-direction optical scanning unit 10 and the Y-directional optical scanning unit 30 excluding the frame 20 described later have a thickness t1 of about 0.1 mm in the Z direction, while the frame The body 20 has a thickness t2 of about 0.5 mm that is larger than t1. The frame 20 is formed on the Si substrate 1 having a thickness t1 of about 0.1 mm, the thin SiO ₂ layer 2 formed on the lower surface (Z2 side) of the Si substrate 1, and the lower surface of the SiO ₂ layer 2. And a lower Si layer 3 having a thickness of about 0.4 mm.

  As shown in FIGS. 1 and 2, the X-direction optical scanning unit 10 is connected to the mirror 11, the torsion bars 12 and 13 that are connected to the mirror 11, and torsionally deformable, and torsion bars 12. , A tiltable bar 15 connected to the torsion bar 13, inner drive parts 16 and 17 connected to the bars 14 and 15, and fixing parts 18 and 19 for fixing the inner drive parts 16 and 17. The frame 20 is included. As shown in FIG. 2, the frame 20 (X-direction optical scanning unit 10) has a length L1 of about 5 mm in the Y direction and a length L2 of about 4 mm in the X direction. The inner drive units 16 and 17 are examples of the “second drive unit” in the present invention.

  Further, the mirror 11 and the torsion bars 12 and 13 are configured to be inclined more than the inclination angle of the bars 14 and 15 by resonance. Further, the rotation center R1 when the oscillating mirror element 100 scans light in the X direction and the rotation center R2 when scanning light in the Y direction are both configured to pass through the center R3 of the mirror 11. . The center R3 of the mirror 11 is configured to be positioned at the center in the X direction and the Y direction of the X direction optical scanning unit 10. The rotation center R1 is an example of the “second rotation center” in the present invention, and the rotation center R2 is an example of the “first rotation center” in the present invention. The Y direction is an example of the “first direction” in the present invention, and the X direction is an example of the “second direction” in the present invention.

  Further, as shown in FIG. 1, the inner drive units 16 and 17 are configured to be deformed into a concave shape or a convex shape in the Z direction, with the fixed portions 18 and 19 being fixed ends, respectively. The inner drive unit 16 and the inner drive unit 17 are deformed in directions opposite to each other so that the mirror 11 can be tilted in the A1 direction or the A2 direction around the rotation center R1 (see FIG. 2). Has been. Further, by repeating this deformation operation, the X-direction optical scanning unit 10 is configured to cause the mirror 11 to vibrate in the A direction around the rotation center R1 and to scan light in the X direction. The detailed structure of the inner drive units 16 and 17 will be described later.

  In addition, as shown in FIG. 2, the Y-direction optical scanning unit 30 includes a driving unit 31 and a mirror support unit 32 formed on the X1 side of the X-directional optical scanning unit 10, and an X2 side of the X-directional optical scanning unit 10. The drive part 33 and the mirror support part 34 which were formed are provided. That is, the drive unit 31, the mirror support unit 32, the drive unit 33, and the mirror support unit 34 are arranged so as to sandwich the X direction optical scanning unit 10 in the X direction. The drive units 31 and 33 and the mirror support units 32 and 34 are formed so as to extend linearly in the Y direction. The drive units 31 and 33 are examples of the “first drive unit” in the present invention.

  Here, in the present embodiment, the Y1 side end 31a of the drive unit 31 and the Y1 side end 33a of the drive unit 33 are fixed by an unshown outer frame. That is, each of the drive units 31 and 33 is a piece having the end portions 31a and 33a as fixed ends and the end portion 31b on the Y2 side of the drive portion 31 and the end portion 33b on the Y2 side of the drive portion 33 as free ends. It has a cantilevered structure. As a result, when the drive units 31 and 33 are driven, the end portions 31b and 33b are displaced in the Z direction (see FIG. 1) by being deformed so that the drive units 31 and 33 are warped. It is configured to be. At this time, the end portions 31a and 33a, which are fixed ends, are not displaced even when the drive portions 31 and 33 are driven. Thus, the tangent lines C1 and C2 at the end portions 31b and 33b that are free ends are configured to be inclined at a predetermined inclination angle with respect to the tangent lines D1 and D2 at the end portions 31a and 33a that are fixed ends. .

  Further, a connection portion 31c is provided in the vicinity of the end portion 31b on the Y2 side of the drive portion 31. The drive unit 31 is connected to a connection part 32b in the vicinity of the end part 32a on the Y2 side of the mirror support part 32 at the connection part 31c. Further, a connecting portion 33c is provided in the vicinity of the Y2 side end portion 33b of the driving portion 33. The drive unit 33 is connected to a connection part 34b in the vicinity of the Y2 side end 34a of the mirror support part 34 at the connection part 33c.

  As shown in FIG. 2, the mirror support portion 32 is formed so as to extend linearly in the Y direction from the connection portion 31 c of the drive portion 31 toward the end portion 31 a on the Y1 side of the drive portion 31. In addition, the mirror support portion 34 is formed to extend linearly in the Y direction from the connection portion 33 c of the drive portion 33 toward the end portion 33 a on the Y1 side of the drive portion 33.

  Further, in this embodiment, the mirror support portion 32 does not bend substantially even when the end portion 31b of the drive portion 31 is displaced in the Z direction (see FIG. 1) in the drive state of the drive portion 31. It is configured. Thereby, in the drive state of the drive part 31, the mirror support part 32 is located on the tangent C1 (refer FIG. 3) in the edge part 31b of the drive part 31 which is a free end, and the drive part 31 which is a fixed end. It is comprised so that it may incline with a predetermined | prescribed inclination | tilt angle with respect to the tangent D1 (refer FIG. 3) in the edge part 31a.

  Further, the mirror support portion 34 is configured so as not to bend substantially even when the end portion 33 b of the drive portion 33 is displaced in the Z direction in the drive state of the drive portion 31. Accordingly, the mirror support portion 34 is positioned on the tangent line C2 (see FIG. 3) at the end portion 33b of the drive portion 33 that is the free end in the drive state of the drive portion 33, so that the drive portion 33 that is the fixed end. It is comprised so that it may incline with a predetermined | prescribed inclination angle with respect to the tangent D2 (refer FIG. 3) in the edge part 33a.

  Further, the mirror support portion 32 is connected at the end portion 32c on the Y1 side in the vicinity of the end portion on the X1 side of the side surface on the Y2 side of the frame body 20 of the X direction optical scanning unit 10. Further, the mirror support portion 34 is connected in the vicinity of the end portion on the X2 side of the side surface on the Y2 side of the frame body 20 of the X direction optical scanning portion 10 at the end portion 34c on the Y1 side. As a result, the X-direction optical scanning unit 10 is positioned on a plane including the tangent line C1 where the mirror support unit 32 is located and the tangent line C2 where the mirror support unit 34 is located. It is configured to incline at an inclination angle.

  In the present embodiment, as shown in FIG. 2, the drive units 31 and 33 have a length L3 of about 14 mm in the Y direction and a width W1 of about 0.8 mm in the X direction. Accordingly, the length L3 in the Y direction of the drive units 31 and 33 is configured to be at least twice as long as the length L1 (about 5 mm) in the Y direction of the X direction optical scanning unit 10. The mirror support portions 32 and 34 have a length L4 of about 4.5 mm in the Y direction and a width W2 of about 0.7 mm in the X direction. At this time, the length L4 (about 4.5 mm) in the Y direction of the mirror support portions 32 and 34 and half (about 2.5 mm) of the length L1 (about 5 mm) in the Y direction of the X direction optical scanning portion 10 In the Y direction from the Y2 side ends (free ends) 31b and 33b (connecting portions 31c and 33c) of the drive units 31 and 33 to the rotation center R2 of the X direction optical scanning unit 10. It is configured to be a distance. Accordingly, the rotation center R2 of the X-direction optical scanning unit 10 is disposed so as to pass through a position of about 7 mm from the Y2 side end portions 31b and 33b (connection portions 31c and 33c) of the driving units 31 and 33 to the Y1 side. At the same time, the Y1 side ends (fixed ends) 31a and 33a of the drive units 31 and 33 are arranged to pass through a position of about 7 mm from the Y2 side. On the other hand, the center R4 in the Y direction of the drive unit 31 is located about 7 mm from the end (fixed end) 31a to the Y2 side and about 7 mm from the end (free end) 31b to the Y1 side. . Further, the center R5 in the Y direction of the drive unit 33 is located at a position about 7 mm from the end (fixed end) 33a to the Y2 side, and at a position about 7 mm from the end (free end) 33b to the Y1 side. . As a result, the rotation center R2 has substantially straight centers R4 and R5 extending in the Y direction connecting the connection portions 31c and 33c and the end portions (fixed ends) 31a and 33a when the drive portions 31 and 33 are not driven. It is arranged at a passing position.

  In the present embodiment, the X-direction optical scanning unit 10 (mirror 11) is supported by the mirror support units 32 and 34 without being bent, so that the X-direction optical scanning unit 10 (mirror 11) is positioned on a plane including the tangent lines C1 and C2. It is configured. Furthermore, in the non-driving state of the drive parts 31 and 33, the rotation center R2 has a substantially straight center R4 and an end part extending in the Y direction connecting the end part (fixed end) 31a and the end part (free end) 31b ( Regardless of the driving state and the non-driving state of the drive units 31 and 33, the fixed portion is disposed at a position passing through the approximate center R5 of the straight line extending in the Y direction connecting the end portion (free end) 33b. The distance between the rotation center R2 and the end portions (free ends) 31b and 33b is substantially the same as the distance between the rotation center R2 and the end portions (fixed ends) 31a and 33a of the first drive unit. As a result, the end portions (free ends) 31b and 33b always connect the rotation center R2 and the end portions (free ends) 31b and 33b regardless of whether the drive portions 31 and 33 are driven or not. A straight line (tangent lines C1 and C2) is used as the radius, and the straight line (tangent lines C1 and C2) is substantially positioned on an arc centered on the rotation center R2. At this time, the end portions (fixed ends) 31a and 33a are fixed, and the tangent lines D1 and D2 at the end portions (fixed ends) 31a and 33a do not change. Therefore, the circle around the rotation center R2 is fixed. It is configured not to move. As a result, it becomes possible to arrange the rotation center R2 at a substantially fixed position regardless of whether the drive units 31 and 33 are driven or not. A specific driving operation of the Y-direction optical scanning unit 30 will be described later.

  Also, as shown in FIGS. 4 to 7, the inner drive parts 16 and 17 (see FIG. 4) and the drive parts 31 and 33 are formed with a piezoelectric actuator 40 on the upper surface (the surface on the Z1 side) of the Si substrate 1. Have a structure. As shown in FIG. 8, the piezoelectric actuator 40 has a structure in which a lower electrode 41, a piezoelectric body 42, and an upper electrode 43 are laminated from the Si substrate 1 side (Z2 side). The lower electrode 41 is made of Ti or Pt and is formed on the upper surface of the Si substrate 1. Thus, the wiring process to the lower electrode 41 of the piezoelectric actuator 40 can be performed on an arbitrary portion of the Si substrate 1. Since the thickness of the piezoelectric actuator 40 is sufficiently smaller than that of the Si substrate 1, the piezoelectric actuator 40 formed in the inner driving portions 16 and 17 and the driving portions 31 and 33 in FIGS. 3, 10, and 12. Is omitted. Since the thickness of the lower electrode 41 is sufficiently small, the illustration of the lower electrode 41 formed on the upper surface of the Si substrate 1 is omitted in the drawings other than FIG.

  The piezoelectric body 42 is made of lead zirconate titanate (PZT) and is configured to expand and contract when a voltage is applied by being polarized in the film thickness direction (Z direction). The piezoelectric body 42 is also formed on the upper surface of the lower electrode 41 of the mirror support portions 32 and 34 (see FIG. 6). In addition, since the thickness of the piezoelectric body 42 is sufficiently small with respect to the Si substrate 1, the illustration of the piezoelectric body 42 formed on the upper surfaces of the mirror support portions 32 and 34 is omitted in FIGS. is doing.

  The upper electrode 43 is made of a conductive metal material such as Al, Cr, Cu, Au, or Pt. The upper electrodes 43 in the inner driving units 16 and 17 are configured to be applied with voltages having opposite phases, while the upper electrodes 43 in the driving units 31 and 33 are applied with voltages having the same phase. It is configured to be.

  Next, the driving operation of the Y-direction optical scanning unit 30 of the vibrating mirror element 100 according to the embodiment of the present invention will be described with reference to FIGS.

  From the state in which the drive units 31 and 33 as shown in FIGS. 1 and 3 are kept in a horizontal state due to the non-drive state, the drive units 31 and 33 are placed on the upper surface side of the piezoelectric actuator 40 as shown in FIG. When a voltage of the same phase is applied so that (Z1 side) is contracted more than the lower surface side (Z2 side), the upper surface side (Z1 side) of the drive units 31 and 33 is contracted more than the lower surface side (Z2 side). The Thereby, in the drive part 31, the drive part 31 warps upwards because the edge part 31b by the side of Y2 which is a free end is located above the edge part 31a by the side of Y1 which is a fixed end (Z1 side). It is deformed as follows. At this time, as shown in FIG. 10, the inclination angle of the end portion (free end) 31b of the drive portion 31 in the B1 direction is θ1 with respect to the tangent line D1 at the end portion 31a (fixed end). Similarly, in the drive unit 33, the end portion 33b on the Y2 side, which is a free end, is positioned above the end portion 33a on the Y1 side, which is a fixed end, so that the drive unit 33 is deformed to warp upward. The At this time, the inclination angle of the end portion (free end) 33b of the drive unit 33 in the B1 direction is θ1 with respect to the tangent line D2 at the end portion (fixed end) 33a.

  As a result, as shown in FIG. 10, the mirror support portion 32 connected to the Y2 side connection portion 31c of the drive portion 31 maintains the inclination angle θ1 of the end portion 31b of the drive portion 31 with respect to the tangent line D1. Inclined in the B1 direction without bending. Similarly, the mirror support portion 34 connected to the Y2 side connection portion 33c of the drive portion 33 maintains the inclination angle θ1 of the end portion 33b of the drive portion 33 with respect to the tangent line D2 and does not bend B1. Tilted in the direction. Accordingly, the X-direction optical scanning unit 10 (mirror 11) is supported by the mirror support unit 32 on the X1 side and the Y2 side, and supported by the mirror support unit 34 on the X2 side and the Y2 side. ) Is inclined in the B1 direction at an inclination angle θ1 with respect to the tangent lines D1 and D2, similarly to the mirror support portions 32 and.

  Further, as shown in FIG. 11, when a large voltage is applied to the drive units 31 and 33 so that the piezoelectric actuator 40 contracts more, the upper surface side (Z1 side) of the drive units 31 and 33 is the lower surface side (Z2 side). The drive parts 31 and 33 are deformed so as to warp further upward. At this time, as shown in FIG. 12, the inclination angle of the end portion 31b of the drive unit 31 in the B1 direction is set to θ2 larger than θ1 (see FIG. 10) with respect to the tangent D1 at the end portion 31a which is a fixed end. Become. Similarly, the inclination angle of the end portion 33b of the drive unit 33 in the B1 direction is θ2 larger than θ1 (see FIG. 10) with respect to the tangent line D2 at the end portion 33a which is a fixed end. As a result, the mirror support parts 32 and 34 and the X-direction optical scanning part 10 (mirror 11) are inclined in the B1 direction at an inclination angle θ2 with respect to the tangent lines D1 and D2, similarly to the mirror support parts 32 and 34.

  Further, the drive units 31 and 33 of the Y-direction optical scanning unit 30 are nonresonantly driven in a direction in which the upper surface side (Z1 side) of the piezoelectric actuator 40 is contracted more than the lower surface side (Z2 side) at a frequency of about 60 Hz. A voltage is applied to. Thus, the X-direction optical scanning unit 10 (mirror 11) is tilted from the horizontal state of FIGS. 1 and 3 at the tilt angle θ1 of FIGS. 9 and 10, and at the tilt angle θ2 of FIGS. After the tilt, the tilt is again tilted in the B1 direction at the tilt angle θ1 of FIGS. 9 and 10 to return to the horizontal state of FIGS. By repeating this series of deformation operations, the drive units 31 and 33 and the mirror support units 32 and 34 cause the mirror 11 to tilt in the B1 direction around the rotation center R2 and scan light in the Y direction.

  Next, with reference to FIG. 7, FIG. 8, FIG. 13 and FIG. 14, a manufacturing process of the vibrating mirror element 100 according to the embodiment of the present invention will be described. 13 and 14 are cross-sectional views taken along line 4000-4000 shown in FIG.

First, as shown in FIG. 13, the Si substrate 1, the SiO ₂ layer 2 formed on the lower surface (Z2 side) of the Si substrate 1, and the lower Si layer 3 formed on the lower surface of the SiO ₂ layer 2 are included. An SOI substrate 4 is prepared. Then, the lower electrode 41 (see FIG. 8) and the piezoelectric body 42 (see FIG. 8) are sequentially formed on the entire upper surface of the SOI substrate 4 (the surface on the Z1 side of the Si substrate 1) by sputtering or the like. Then, the upper electrode 43 (see FIG. 8) is formed on the upper surface of the piezoelectric body 42 corresponding to the inner driving units 16 and 17 and the driving units 31 and 33 by vapor deposition or the like. In this way, the piezoelectric actuator 40 is formed in the inner drive units 16 and 17 and the drive units 31 and 33.

  Then, after a resist pattern (not shown) is formed by photolithography at positions corresponding to the inner drive parts 16 and 17, the drive parts 31 and 33, and the mirror support parts 32 and 34, the resist pattern is used as a mask. By performing wet etching or the like, the piezoelectric body 42 formed at a position other than the position corresponding to the inner driving sections 16 and 17, the driving sections 31 and 33, and the mirror support sections 32 and 34 is removed. Thereafter, a mask made of Al, Cr, Cu, Au, Pt, or the like by vapor deposition or the like at a position corresponding to the frame 20 on the lower surface of the SOI substrate 4 (the surface on the Z2 side of the lower Si layer 3) and the outer frame not shown. Pattern 5 is formed.

  Then, after a resist pattern (not shown) is formed by photolithography at a position corresponding to the vibrating mirror element 100, wet etching or the like is performed using the resist pattern as a mask, so that a position other than the position corresponding to the vibrating mirror element 100 is obtained. The lower electrode 41 (see FIG. 8) formed at the position is removed. Thereby, the lower electrode 41 is formed only on the upper surface (the surface on the Z1 side) of the Si substrate 1 on which the oscillating mirror element 100 is formed.

Thereafter, as shown in FIG. 14, the Si substrate 1 formed at a position other than the position corresponding to the vibrating mirror element 100 is removed by reactive ion etching (RIE) or the like. Thereafter, the lower Si layer 3 formed at a position other than the position corresponding to the frame body 20 and the outer frame body (not shown) is removed by reactive ion etching (RIE) or the like using the mask pattern 5 as a mask. Thereafter, the SiO ₂ layer 2 formed at a position other than the position corresponding to the vibrating mirror element 100 is removed by reactive ion etching (RIE) or the like. Thereby, the vibrating mirror element 100 shown in FIG. 7 is formed.

  In the present embodiment, as described above, the X-direction optical scanning unit 10 (mirror 11) is supported by the mirror support units 32 and 34 so as to have substantially the same inclination as that of the end parts (free ends) 31b and 33b. With this configuration, when the drive units 31 and 33 are driven and the X-direction light scanning unit 10 is tilted together with the end portions (free ends) 31b and 33b of the drive units 31 and 33, the X-direction light scanning unit 10 is It can be inclined at substantially the same inclination angle as the end portions (free ends) 31b and 33b. That is, regardless of the drive state and non-drive state of the drive units 31 and 33, the rotation center R2 is substantially disposed at a position passing through the tangent lines C1 and C2 at the end portions (free ends) 31b and 33b. Furthermore, in the non-driving state of the drive parts 31 and 33, the rotation center R2 has a substantially straight center R4 and an end part extending in the Y direction connecting the end part (fixed end) 31a and the end part (free end) 31b ( Regardless of the driving state and the non-driving state of the drive units 31 and 33, the fixed portion is disposed at a position passing through the approximate center R5 of the straight line extending in the Y direction connecting the end portion (free end) 33b. The distance between the rotation center R2 and the end portions (free ends) 31b and 33b and the distance between the rotation center R2 and the end portions (fixed ends) 31a and 33a of the first drive unit may be substantially the same. it can. Thus, the end portions (free ends) 31b and 33b are always connected to the rotation center R2 and the end portions (free ends) 31b and 33b regardless of the drive state and non-drive state of the drive units 31 and 33. The straight line (tangent line C1 and C2) is a radius, and can be positioned substantially on an arc centered on the rotation center R2. At this time, the end portions (fixed ends) 31a and 33a are fixed, and the tangent lines D1 and D2 at the end portions (fixed ends) 31a and 33a do not change. Therefore, the circle around the rotation center R2 is fixed. Do not move. As a result, the rotation center R2 is substantially disposed at a position passing through the centers R4 and R5 in the non-driven state of the drive units 31 and 33, so that the rotation center R2 is intersected with the intersection of the tangent line D1 and the tangent line C1 and the tangent line D2. Since it can be arranged at a position passing through the intersection with the tangent line C2, the rotation center R2 can be arranged at a substantially fixed position regardless of whether the drive units 31 and 33 are driven or not. Accordingly, the X-direction optical scanning unit 10 can be rotated around the rotation center R2 so as to have substantially the same inclination as the end portions 31b and 33b in a state where the position of the rotation center R2 does not substantially change. The directional light scanning unit 10 (mirror 11) can reflect light with high accuracy.

  In the present embodiment, as described above, the Y1 side ends 31a and 33a of the drive units 31 and 33 are fixed ends, and the Y2 side ends 31b and 33b are free ends. By causing the parts 31 and 33 to perform the same drive, the inclination of the connection parts 31c and 33c of the drive parts 31 and 33 can be controlled to substantially the same inclination angle, so that the mirror support parts 32 and 34 and X The directional light scanning unit 10 (mirror 11) can be tilted at substantially the same tilt angle as the connection portions 31c and 33c of the drive units 31 and 33, respectively. As a result, light can be accurately reflected by the X-direction optical scanning unit 10 (mirror 11).

  In the present embodiment, as described above, the drive unit 31, the mirror support unit 32, the drive unit 33, and the mirror support unit 34 are arranged so as to sandwich the X direction optical scanning unit 10 in the X direction. Since the X direction optical scanning unit 10 can be rotated around the rotation center R2 while the X direction optical scanning unit 10 (mirror 11) is supported from both sides in the X direction, the X direction optical scanning can be performed more stably. The part 10 can be rotated.

  In the present embodiment, as described above, the rotation center R2 is located at a position passing through the intersection of the tangent C1 at the end (fixed end) 31a and the tangent D1 at the end (free end) 31b, and at the end. Even if the drive units 31 and 33 are driven while being deformed by being arranged at a position passing through the intersection of the tangent line C2 at the portion (fixed end) 33a and the tangent line D2 at the end portion (free end) 33b, Since the position of the moving center R2 can be configured so as not to change substantially regardless of the driving state and non-driving state of the driving units 31 and 33, the light is accurately reflected by the X-direction optical scanning unit 10 (mirror 11). Can be made.

  In the present embodiment, as described above, the X-direction optical scanning unit 10 is positioned on a plane including the tangent line C1 at the end 31b of the drive unit 31 and the tangent line C2 at the end 33b of the drive unit 33. By configuring, the inclination of the end part (free end) 31b of the drive part 31, the inclination of the end part (free end) 33b of the drive part 33, the inclination of the mirror support part 32, and the inclination of the mirror support part 34 The X-direction light scanning unit 10 (mirror 11) can be tilted about the rotation center R2 while maintaining the inclination of the X-direction light scanning unit 10 (mirror 11) to be substantially the same.

  In the present embodiment, as described above, the same phase voltage (X direction) is easily applied to the drive unit 31 and the drive unit 33 by applying the same phase voltage to the upper electrode 43 in the drive units 31 and 33. The same degree of deformation can be caused in the direction in which the optical scanning unit 10 (mirror 11) is rotated.

  In the present embodiment, as described above, the connection portions 31c and 33c are formed in the vicinity of the Y2 side end portions (free ends) 31b and 33b, respectively, thereby increasing the inclination angle of the connection portions 31c and 33c. Therefore, the tiltable angle range of the X-direction optical scanning unit 10 (mirror 11) can be secured more widely.

  In the present embodiment, as described above, the length L3 (about 14 mm) in the Y direction of the drive units 31 and 33 is more than twice the length L1 (about 5 mm) in the Y direction of the X direction optical scanning unit 10. Accordingly, the driving force of the driving units 31 and 33 can be easily increased by the length of the driving units 31 and 33, so that the end portions 31b and 33b of the driving units 31 and 33 can be easily set. The inclination angle at can be further increased. Thereby, the angle range which can incline the X direction optical scanning part 10 (mirror 11) can be ensured more widely.

  In the present embodiment, as described above, the mirror 11 is provided by providing the X-direction optical scanning unit 10 with the mirror 11 and the inner drive units 16 and 17 that rotate the mirror 11 around the rotation center R1. The light can be accurately reflected around the rotation center R2, and the light can be scanned two-dimensionally by the rotation about the rotation center R1 and the rotation about the rotation center R2.

  In the present embodiment, as described above, the X-direction optical scanning unit 10 is configured to be resonantly driven at a resonance frequency of about 30 kHz, while the Y-direction optical scanning unit 30 is non-resonant at a frequency of about 60 Hz. By being configured to drive, the X-direction optical scanning unit 10 scans light two-dimensionally in a state where the X-direction optical scanning unit 10 is configured to rotate at a greater frequency about the rotation center R1 than about the rotation center R2. be able to.

  Further, in the present embodiment, as described above, the drive unit 31, the mirror support unit 32, the drive unit 33, the mirror support unit 34 (Y direction light scanning unit 30), and the X direction light scan unit 10 are shared. By integrally forming on the Si substrate 1, the connection between the drive unit 31 and the mirror support unit 32, the connection between the drive unit 33 and the mirror support unit 34, and the mirror support units 32 and 34 and the X-direction optical scanning unit 10. Therefore, the manufacturing process of the vibrating mirror element 100 can be simplified.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above embodiment, the vibrating mirror element 100 includes the X direction light scanning unit 10 and the Y direction light scanning unit 30 and the mirror 11 is rotated in the A direction and the B1 direction (two-dimensional). However, the present invention is not limited to this. For example, unlike the oscillating mirror element 200 in the modification shown in FIG. 15, the Y-direction light scanning unit 230 and the mirror 211 are provided without the X-direction light scanning unit, thereby making it possible to You may comprise so that it may rotate only to the B1 direction (refer FIG. 1) (one-dimensionally). At this time, the mirror 211 is connected to the end portion 232d on the Y1 side of the mirror support portion 232 on the X1 side, and is connected to the end portion 234d on the Y1 side of the mirror support portion 234 on the X2 side. Thus, the mirror 211 is configured to be tiltable in the B1 direction. The rotation center R2 is the Y direction connecting the connection portions 31c and 33c (end portions (free ends) 31b and 33b) and the end portions (fixed ends) 31a and 33a when the drive portions 31 and 33 are not driven. It is arrange | positioned in the position which passes along the approximate center of the straight line extended to. The mirror 211 is an example of the “mirror part” in the present invention.

  In the above embodiment, the example in which the pair of drive units 31 and 33 and the pair of mirror support units 32 and 34 are provided in the Y-direction optical scanning unit 30 of the oscillating mirror element 100 has been described. Not limited. In the present invention, only one drive part and mirror support part of the vibrating mirror element may be formed on either side in the X direction. In addition, the vibration mirror element includes a plurality of drive units and mirror support units arranged alternately in the X direction, and a plurality of drive units and mirrors are connected by connecting adjacent drive units and mirror support units to each other. You may comprise so that it may have a support part.

  Moreover, in the said embodiment, while providing the connection part 31c in the vicinity of the edge part 31b by the side of Y2 of the drive part 31, the connection part 33c was provided in the vicinity of the edge part 33b by the side of Y2 of the drive part 33 was shown. However, the present invention is not limited to this. In the present invention, as long as the connection part is provided on the free end side of the drive part, the connection part may not be provided near the end part of the drive part.

  In the above embodiment, an example in which the length L3 (about 14 mm) in the Y direction of the drive units 31 and 33 is set to be twice or more the length L1 (about 5 mm) in the Y direction of the X direction optical scanning unit 10 is shown. However, the present invention is not limited to this. In the present invention, the length of the drive unit in the Y direction may be greater than 1 time and less than or equal to 2 times that of the X direction optical scanning unit (mirror unit). Further, the length of the drive unit in the Y direction may be substantially the same as or smaller than the length of the X direction optical scanning unit in the Y direction.

Moreover, although the piezoelectric body 42 showed the example which consists of lead zirconate titanate (PZT) in the said embodiment, this invention is not limited to this. For example, it may be formed of a piezoelectric material made of an oxide mainly composed of lead, titanium and zirconium other than PZT, or other piezoelectric materials. Specifically, the piezoelectric body includes zinc oxide (ZnO), lead lanthanum zirconate titanate ((Pb, La) (Zr, Ti) O ₃ ), potassium niobate (KNbO ₃ ), sodium niobate (NaNbO). _It may be formed of a piezoelectric material such as ₃ ).

  In the above embodiment, an example is shown in which the Y-direction optical scanning unit 30 is configured to be non-resonantly driven at a frequency of about 60 Hz. However, the present invention is not limited to this. In the present invention, the Y-direction optical scanning unit may be configured to be resonantly driven. The Y direction optical scanning unit is preferably non-resonantly driven at a frequency of about 30 Hz to about 120 Hz.

  In the above embodiment, the drive unit 31, the mirror support unit 32, the drive unit 33, the mirror support unit 34 (Y direction light scanning unit 30), and the X direction light scan unit 10 are placed on the common Si substrate 1. Although the example formed integrally was shown, this invention is not limited to this. In the present invention, the Y direction optical scanning unit and the X direction optical scanning unit may not be formed integrally, and the drive unit and the mirror support unit of the Y direction optical scanning unit may not be formed integrally. . For example, the Y-direction optical scanning unit may be formed by separately creating the drive unit and the mirror support unit and then joining them together.

  Moreover, in the said embodiment, the inner side drive parts 16 and 17 and the drive parts 31 and 33 showed the example containing the piezoelectric actuator 40 which has the structure where the lower electrode 41, the piezoelectric body 42, and the upper electrode 43 were laminated | stacked. However, the present invention is not limited to this. In the present invention, the inner drive unit and the drive unit may be configured to be driven by a drive device other than the piezoelectric actuator. For example, a driving device made of an elastomer sandwiched between electrodes may be used. At this time, by applying a voltage between the electrodes, the electrodes are attracted to each other, so that the elastomer is compressed and the driving device is deformed.

10 X-direction optical scanning unit (mirror unit)
11 Mirror 16, 17 Inner drive part (second drive part)
31, 33 Drive unit (first drive unit)
31a, 33a End (fixed end)
31b, 33b end (free end)
31c, 33c Connection part 32, 34, 232, 234 Mirror support part 100, 200 Vibrating mirror element 211 Mirror (mirror part)
R1 rotation center (second rotation center)
R2 center of rotation (first center of rotation)

Claims (11)

A fixed end formed on one side in the first direction, a free end formed on the other side in the first direction, and a connection portion formed on the free end side, along the first direction A linearly extending and deformable cantilevered first drive unit;
A mirror support part connected to the connection part of the first drive part, and configured to have substantially the same inclination as the inclination in the connection part when the first drive part is driven;
The mirror part rotated about the first rotation center extending in the second direction orthogonal to the first direction by being supported by the mirror support part so as to have substantially the same inclination as the inclination in the connection part. And
The first rotation center is disposed at a position that passes through a substantially center of a straight line extending in the first direction connecting the fixed end of the first drive unit and the connection unit when the first drive unit is not driven. A vibrating mirror element.   When driving while deforming the first drive unit, the first rotation center is at a position passing through an intersection of a tangent line at the fixed end of the first drive unit and a tangent line at the connection unit of the first drive unit. The vibrating mirror element according to claim 1, wherein the vibrating mirror element is arranged and configured so that a position of the first rotation center does not substantially change.   When driving while deforming the first driving unit, the mirror support unit and the mirror unit are positioned on substantially the same plane having substantially the same inclination as the inclination of the connection part of the first driving unit. The vibrating mirror element according to claim 1, wherein the vibrating mirror element is configured as follows. The first drive unit and the mirror support unit are provided as a pair so as to sandwich the mirror unit on both sides of the mirror unit in the second direction,
The fixed ends of the pair of first drive parts are both arranged on one side of the mirror part in the first direction, and the free ends of the pair of first drive parts are both of the mirror part in the first direction. Placed on the other side,
The first rotation center is substantially the center of a straight line extending in the first direction connecting the fixed ends of the pair of first drive units and the connection unit when the pair of first drive units is not driven. The vibrating mirror element according to claim 1, wherein the vibrating mirror element is disposed at a passing position. The pair of first driving units are configured to be driven by applying a voltage,
The vibrating mirror element according to claim 4, wherein voltages of substantially the same phase are applied to the pair of first drive units. The connection portion of the first drive unit is formed near the free end of the first drive unit,
The mirror support part is connected to the connection part of the first drive part in the vicinity of one end part of the mirror support part, and extends in the first direction from the connection part toward the fixed end side of the first drive part. The vibrating mirror element according to claim 1, wherein the vibrating mirror element is formed so as to extend linearly and connected to the mirror portion in the vicinity of the other end of the mirror support portion.   The vibrating mirror element according to claim 1, wherein in the first direction, a length of the first drive unit is larger than a length of the mirror unit.   The vibrating mirror element according to claim 7, wherein in the first direction, the length of the first drive unit is twice or more the length of the mirror unit.   The said mirror part contains a mirror and the 2nd drive part which rotates the said mirror around the 2nd rotation center orthogonal to a said 1st rotation center in the in-plane direction of the said mirror. The vibrating mirror element according to any one of the above. The first drive unit is configured to rotate the mirror unit around the first rotation center based on a first frequency,
10. The vibrating mirror according to claim 9, wherein the second driving unit is configured to rotate the mirror around the second rotation center based on a second frequency higher than the first frequency. element.   The vibrating mirror element according to claim 1, wherein the first drive unit, the mirror support unit, and the mirror unit are integrally formed.

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