Reflector scanner

Abstract

To provide a reflector scanner capable of suppressing manufacturing cost and crosstalk.SOLUTION: A reflector scanner includes; a frame that has a frame-shaped portion and a pair of bridging portions and being rotatably held about a first axis; a mirror portion that is connected to the inside of the frame via a first elastic member that extends in a second axis direction; and first and second driving units. The first driving unit includes: a magnet pair with magnets facing each other across the frame on the first axis; a first coil wired in a first annular portion including one bridging portion close to one magnet of the magnet pair and a portion of the frame-shaped portion on a one magnet side; and a second coil wired in a second annular portion including the other bridging portion close to the other magnet of the magnet pair and a portion of the frame-shaped portion on the other magnet side. The second driving unit includes: a second magnet pair with magnets facing each other across a region between the pair of bridging portions of the frame on the second axis; and a third coil at least wired in a region between the pair of bridging portions of the frame-shaped portion.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present invention relates to a reflector scanner that scans the orientation of a reflector. [Background technology]

[0002] As such a reflector scanner, a driving device having a MEMS (Micro Electro Mechanical Systems) structure that reflects received light while scanning it in two axial directions perpendicular to each other is known.

[0003] Furthermore, as the driving device, one has been proposed that has a plate-like, rectangular first movable part having three openings arranged side by side along a first direction, a second movable part with a reflective surface, and a support body (see Patent Document 1).

[0004] The second movable part is supported by a pair of first torsion bars extending in a first direction within a central opening of the first movable part. The support supports the first movable part by a pair of second torsion bars extending in a second direction perpendicular to the first direction.

[0005] On the surface of the first movable part, a first coil wired to surround the central opening, and a second coil wired to surround three openings along the four ends of the first movable part are arranged. In addition, a pair of magnetic members magnetized to different polarities by a first pair of magnets are provided in the openings at both ends of the three openings of the first movable part. The pair of magnets is arranged below the central opening of the first movable part. Furthermore, a pair of second magnets with faces of different polarities facing each other are arranged around the support body near a pair of sections along the second direction in the second coil.

[0006] With this configuration, by intermittently passing a current through the first coil, a force is applied to a region (referred to as the first region) on the first movable part where the first coil is arranged and along the magnetic member, and the second movable part oscillates around the first torsion bar as a central axis. Also, by intermittently passing a current through the second coil, a force is applied to a region (referred to as the second region) on the first movable part where the second coil is arranged and along the second magnet, and the second movable part oscillates around the second torsion bar as a central axis. This allows the orientation of the reflecting surface of the second movable part to be scanned in the first and second directions, making it possible to scan the received light in two axial directions. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 6726356 Summary of the Invention [Problem to be solved by the invention]

[0008] Incidentally, in the drive device described in Patent Document 1, not only the second coil but also the first coil are wired in the region along the side adjacent to the second magnet at the end of the four sides of the first movable part. Therefore, in this drive device, in order to prevent a force acting on this region due to the current flowing through the first coil, that is, so-called crosstalk, the second magnet is arranged in four separate locations in this region, excluding the section in which the first coil is wired.

[0009] Therefore, when constructing such a drive device, in addition to the first pair of magnets, four second magnets, i.e., six systems of magnets, must be prepared and installed in separate locations, which increases the number of parts and complicates the structure, resulting in higher manufacturing costs.

[0010] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a reflector scanner capable of reducing manufacturing costs and crosstalk. [Means for solving the problem]

[0011] A reflector scanner according to the present invention includes a frame having a frame-like portion extending along one surface and held rotatably around a first axis along the first surface, a mirror portion connected to an inside of the frame via a first elastic member extending along a second axis along the first surface, a first drive unit that rotates the frame in a direction of rotation about the second axis as a central axis, and a second drive unit that rotates the frame in a direction of rotation about the first axis as a central axis, the frame extending inside the frame so as to sandwich the first axis and having a pair of bridging portions that span across portions of the frame facing each other across the second axis, the first drive unit having a first magnetic field that is arranged opposite each other on the first axis so as to sandwich the frame therebetween. The second driving unit includes a pair of magnets, a first coil wired to a first annular portion formed by one bridging portion closer to one magnet of the first magnet pair than the mirror portion and a portion of the frame-shaped portion on one side of the first magnet pair than the first bridging portion, and a second coil wired to a second annular portion formed by another bridging portion closer to the other magnet of the first magnet pair than the mirror portion and a portion of the frame-shaped portion on the other side of the first magnet pair than the other bridging portion, and the second driving unit includes a second magnet pair arranged opposite each other on the second axis to sandwich the area between the pair of bridging portions of the frame, and a third coil wired at least to the area between the pair of bridging portions of the frame-shaped portion.

[0012] The reflector scanner according to the present invention includes a frame having a frame-shaped portion extending along one surface and held rotatably around a first axis along the first surface, a mirror portion connected to the inside of the frame via a first elastic member extending along a second axis along the first surface, a pair of magnets arranged opposite each other to sandwich the frame, a coil wired to the frame-shaped portion of the frame and the set of bridge portions, a first support pillar installed inside the frame formed by the first annular portion, and a second support pillar installed on the inside of the frame formed by the second annular portion. and a second support pillar installed inside a frame having a first axis and a second support pillar installed inside the frame, the frame extending inside the frame so as to sandwich the first axis and having a set of bridging parts spanning opposing parts of the frame on either side of the second axis, the first support pillar being connected to one of the set of bridging parts via an elastic member that stretches along the first axis, and the second support pillar being connected to the other of the set of bridging parts via an elastic member that stretches along the first axis. Effect of the Invention

[0013] According to the present invention, by using four magnets, the influence (crosstalk) that the driving current passed through the coil to rotate the frame to which the mirror section is connected via the elastic member in a direction of rotation about the second axis can be exerted on the force to rotate the frame in a direction of rotation about the first axis can be reduced, thereby allowing the mirror section to oscillate in two axial directions.

[0014] Therefore, according to the present invention, it is possible to reduce the device scale and manufacturing costs. [Brief description of the drawings]

[0015] [Figure 1A] FIG. 1 is a top view of a reflector scanner 200 according to a first embodiment of the present invention. [Figure 1B] FIG. 2 is a side view of a reflector scanner 200. [Diagram 2]2 is a top view of the reflector scanner 200 showing the direction of the current flowing in each coil of the reflector scanner 200, the direction of the magnetic field, and the direction of the Lorentz force. [Figure 3A] FIG. 3 is a top view of a reflector scanner 300 according to a second embodiment of the present invention. [Figure 3B] FIG. 3 is a side view of a reflector scanner 300. [Figure 4] 3 is a top view of the reflector scanner 300 showing the direction of the current flowing in each coil of the reflector scanner 300, the direction of the magnetic field, and the direction of the Lorentz force. [Diagram 5] FIG. 4 is a top view of a reflector scanner 400 according to a third embodiment of the present invention. [Figure 6A] FIG. 5 is a top view of a reflector scanner 500 according to a fourth embodiment of the present invention. [Figure 6B] FIG. 5 is a side view of a reflector scanner 500. [Figure 7] FIG. 6 is a top view of a reflector scanner 600 according to a fifth embodiment of the present invention. [Figure 8] FIG. 7 is a top view of a reflector scanner 700 which is a modification of the reflector scanner 600 according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. EXAMPLES

[0017] FIG. 1A is a top view of a reflector scanner 200 according to a first embodiment of the present invention, and FIG. 1B is a side view of the reflector scanner 200 as viewed from the direction of the white arrow shown in FIG. 1A.

[0018] The reflector scanner 200 is, for example, a MEMS (Micro Electro Mechanical System) mirror in which a mirror part MR having a reflective surface is configured to oscillate in two axial directions, with a first axis J1 and a second axis J2 perpendicular to the first axis J1 as the central axes of rotation.

[0019] As shown in FIGS. 1A and 1B, the reflector scanner 200 includes a frame 20, support columns 21a and 21b, a pair of magnets 31a and 31b as a first magnet, a pair of magnets 32a and 32b as a second magnet, and a base 40.

[0020] The frame 20 is divided into a frame portion FR extending along the outer edge of one surface of the frame 20 by the openings Oa, Os, and Ob arranged side by side along the direction of the first axis J1, and a pair of bridging portions consisting of a bridging portion Ba between the openings Oa and Os and a bridging portion Bb between the openings Ob and Os. In other words, the frame 20 is composed of the frame portion FR extending along the outer edge, and a pair of bridging portions (Ba, Bb) that bridge, i.e. connect, the frame portions FR, which extend on either side of the first axis J1, at portions facing each other across the second axis J2.

[0021] In the frame 20, an annular region consisting of the bridging part Ba, which is closer to the magnet 31a, of the pair of bridging parts (Ba, Bb), and the frame part FR around the opening Oa is referred to as an annular region Ra. Furthermore, in the frame 20, an annular region consisting of the bridging part, which is closer to the magnet 31b, of the pair of bridging parts, and the frame part FR around the opening Ob is referred to as an annular region Rb.

[0022] Within the opening Os, i.e., in the region between the bridging portions Ba and Bb, there is provided a mirror portion MR which is connected to the frame portion FR of the frame 20 via torsion bars T1a and T1b extending along the second axis J2.

[0023] Within the opening Oa, that is, inside the annular region Ra, a support column 21a is provided which is connected to the frame portion FR of the frame 20 via a torsion bar T2a extending along the first axis J1.

[0024] Within the opening Ob, i.e., inside the annular region Rb, a support 21b is installed which is connected to the frame portion FR of the frame 20 via a torsion bar T2b as an elastic member stretched along the first axis J1. Each of the torsion bars T1a, T1b, T2a, and T2b is made of an elastic member.

[0025] A coil L1 wired in a loop or spiral shape is disposed in the annular portion of the annular region Ra. One end and the other end of the wire constituting the coil L1 are connected to the power supply circuit 50 via a pair of wires wired on the surface of the torsion bar T2a, inside the support 21a, and inside the base 40.

[0026] A coil L2 wired in a loop or spiral shape is disposed in the annular portion of the annular region Rb. One end and the other end of the wire constituting the coil L2 are connected to the power supply circuit 50 via a pair of wires wired on the surface of the torsion bar T2b, inside the support column 21b, and inside the base 40.

[0027] Furthermore, in the region (hereinafter also referred to as the central region) between the pair of bridge parts (Ba, Bb), a coil L3 (indicated by a broken line) is arranged in a loop or spiral shape surrounding the mirror part MR. One end of the wiring constituting the coil L3 is connected to the power supply circuit 50 via wiring provided on the frame part FR, the surface of the torsion bar T2a, the support pillar 21a, and the inside of the base 40. The other end of the wiring constituting the coil L3 is connected to the power supply circuit 50 via wiring provided on the frame part FR, the surface of the torsion bar T2b, the support pillar 21b, and the inside of the base 40. The support pillars 21a and 21b are installed on the base 40. Regarding the wiring for the pillars 21a and 21b, the wiring may be performed inside the pillars by using TSVs (through silicon vias) as the pillars, or bonding pads may be provided on the surfaces of the pillars and the wiring may be led out to the outside by wire bonding across the frame 20 and the magnets (31a, 31b).

[0028] 1A, in the frame 20, a coil L1 is installed in the annular region Ra, and a coil L2 is installed in the annular region Rb. Furthermore, a mirror section MR and a third coil L3 are installed in the central region between the annular regions Ra and Rb, that is, the region between the pair of bridge sections. Note that the coil L3 includes a wiring section that is wired close to the magnet 32a or 32b so as to cross the region sandwiched between at least a pair of magnets 32a and 32b.

[0029] The power supply circuit 50 supplies a first driving current, which is an AC current for oscillating the mirror portion MR in the direction of rotation about the second axis J2, to each of the coils L1 and L2. Furthermore, the power supply circuit 50 supplies a second driving current, which is an AC current for oscillating the mirror portion MR in the direction of rotation about the first axis J1, to the coil L3. Note that, although the power supply circuit 50 is installed at a position separated from the base 40 in FIG. 1B, it may be installed directly on the base 40.

[0030] The magnets 31a, 31b, 32a, and 32b are installed on the base 40 so that one is disposed at each of the outer circumferential positions close to each side of the frame 20. The height of each of the magnets 31a, 31b, 32a, and 32b from the surface of the base 40 is equal to or greater than the height from the base 40 to the surface of the frame 20.

[0031] The magnets 31a and 31b as the first magnet pair are mounted on the base 40 on the first axis J1 so as to sandwich the frame 20 with their faces of opposite polarity facing each other.

[0032] The magnets 32a and 32b as a second magnet pair are mounted on the base 40 on the second axis J2 so as to sandwich the frame 20 with their faces of opposite polarity facing each other.

[0033] The length of each of the magnets 32a and 32b in the direction along the first axis J1 is set to a length that is at least long enough to sandwich the central region, that is, the region between a pair of bridging portions (Ba, Bb).

[0034] The operation of the reflector scanner 200 will now be described with reference to FIG.

[0035] 2 is a top view of the reflector scanner 200, with symbols or arrows indicating the direction of the current flowing through each coil of the reflector scanner 200 at a given time, the direction of the magnetic field, and the direction of the Lorentz force.

[0036] The power supply circuit 50 supplies the coil L1 with the driving current i1, which is an AC current, and supplies the coil L2 with the driving current i1e, which is an AC current with the phase inverted from that of the driving current i1. As a result, at a certain point in time, the driving current i1 flows in the coil L1 in a clockwise direction as shown by the arrow in FIG. 2, for example, and the driving current i1e flows in the coil L2 in a clockwise direction as shown by the arrow in FIG. 2, for example.

[0037] Therefore, a first Lorentz force is applied to the left end of the frame 20 in response to the magnetic field B1 (indicated by a hollow arrow) generated by the magnet 31a and the drive current i1 (indicated by a black arrow) crossing the magnetic field B1. Furthermore, a second Lorentz force is applied to the right end of the frame 20 in response to the magnetic field B1e (indicated by a hollow arrow) generated by the magnet 31b and the drive current i1e (indicated by a black arrow) crossing the magnetic field B1e. At this time, the direction in which the first Lorentz force is applied and the direction in which the second Lorentz force is applied are opposite to each other, that is, when one of the first and second Lorentz forces is applied in the direction in which the front surface of the frame 20 faces, the other is applied in the direction in which the back surface of the frame 20 faces. As a result, a force (couple force) that rotates the frame 20 about the second axis J2 as the central axis is applied to the frame 20. Furthermore, since the drive currents i1 and i1e are alternating currents, the directions of the Lorentz forces acting on the right and left ends of the frame 20, respectively, are reversed at a period corresponding to the frequency of the alternating current while maintaining mutually opposite directions.

[0038] As a result, the frame 20 reverses the direction of rotation around the second axis J2 at a period corresponding to the frequency of the AC current, and the torsion bars T1a and T1b, receiving the inertial force, twist has the mirror portion MR oscillate in the direction of rotation around the second axis J2.

[0039] Incidentally, the direction of the drive current flowing through the bridge portion Ba (Bb) of the coil L1 (L2) is opposite to the direction of the drive current flowing through the frame portion FR on the left (right) end side of the frame 20. Therefore, the Lorentz force acting on the bridge portion Ba (Bb) due to the magnetic field B1 (B1e) shown in FIG. 2 is opposite to the Lorentz force acting on the left (right) end of the frame 20, that is, in the direction that hinders the rotational movement of the frame 20. However, the distance from the bridge portion Ba (Bb) to the magnet 31a (31b) is longer than the distance from the frame portion FR at the left (right) end of the frame 20 to the magnet 31a (31b). Therefore, the magnetic field b1 (b1e) at the bridge portion Ba (Bb) generated by the magnet 31a (31b) is smaller than the magnetic field B1 (B1e), so the generated torque is also small and the effect of hindering the rotational movement of the frame 20 is small.

[0040] In addition, in the reflector scanner 200, the power supply circuit 50 supplies the driving current i2, which is an AC current, to the coil L3. As a result, at a certain point in time, the driving current i2 flows through the coil L3 in the frame portion FR in the direction indicated by the arrow in FIG.

[0041] Therefore, a third Lorentz force is applied to the frame portion FR at the upper end of the frame 20 in response to the magnetic field B2 (indicated by a hollow arrow) generated by the magnet 32a and the drive current i2 (indicated by a black arrow) crossing the magnetic field B1. Furthermore, a fourth Lorentz force is applied to the frame portion FR at the lower end of the frame 20 in response to the magnetic field B2e (indicated by a hollow arrow) generated by the magnet 32b and the drive current i2 (indicated by a black arrow) crossing the magnetic field B2e. At this time, the direction in which the third Lorentz force is applied and the direction in which the fourth Lorentz force is applied are opposite to each other, that is, when one of the third and fourth Lorentz forces is applied in the direction in which the front surface of the frame 20 faces, the other is applied in the direction in which the back surface of the frame 20 faces. As a result, a force (couple force) that rotates the frame 20 about the first axis J1 as the central axis is applied to the frame 20. Furthermore, since the driving current i2 is an AC current, the directions of the Lorentz forces acting on the upper and lower ends of the frame 20 are reversed at a period corresponding to the frequency of the AC current while maintaining a state in which they are opposite to each other.

[0042] As a result, the frame 20 reverses the direction of rotation around the first axis J1 at a period corresponding to the frequency of the AC current, and the torsion bars T2a and T2b, receiving the inertial force, twist, causing the mirror portion MR to oscillate in the direction of rotation around the first axis J1.

[0043] By the way, due to the magnetic field b1 (b1e) applied to the bridging portion Ba (Bb) and the driving current i2 flowing through the coil L3 across the magnetic field b1 (b1e), a couple of forces that rotate the frame 20 about the second axis J2 is also applied to the bridging portion Ba (Bb) as crosstalk. However, as described above, the distance from the bridging portion Ba (Bb) to the magnet 31a (31b) is longer than the distance from the left (right) end of the frame 20 to the magnet 31a (31b). Furthermore, since the distance from the bridging portion Ba (Bb) to the second axis J2 is short, the torque generated on the bridging portion Ba (Bb) is small, and the influence of crosstalk is also small.

[0044] 1A, the frame 20 is provided with one pair of bridging parts (Ba, Bb), but the number of bridging parts provided on the frame 20 is not limited to two. In other words, as long as the frame 20 is formed with one pair of bridging parts (Ba, Bb) surrounding the mirror part MR, the number of bridging parts may be three or more.

[0045] In short, the reflector scanner 200 employs a configuration including the following frame, mirror unit, and first and second drive units, thereby causing the mirror unit to oscillate in two axial directions.

[0046] That is, the frame (20) has a frame-like portion (FR) extending along one surface, and is held rotatably around a first axis (J1) along the one surface. The frame extends so as to sandwich the first axis inside itself, and has a pair of bridge portions (Ba, Bb) that span across opposing portions across a second axis (J2) along the one surface. The mirror portion (MR) is connected to the inside of the frame via a first elastic member (T1a, T1b) that extends along the second axis along the one surface. The first driving portion (31a, 31b, L1, L2) rotates the frame in a direction of rotation about the second axis as a central axis, and the second driving portion (32a, 32b, L3) rotates the frame in a direction of rotation about the first axis as a central axis. Here, the first driving unit includes a first magnet pair (31a, 31b) arranged facing each other on the first axis so as to sandwich the frame, and first and second coils wired to the frame. The first coil (L1) is wired to a first annular portion (Ra) formed by a first bridging portion (Ba) closer to one magnet (31a) of the first magnet pair (31a, 31b) than the mirror portion and a portion of the frame-shaped portion (FR) on one side of the first magnet pair than the first bridging portion. The second coil (L2) is wired to a second annular portion (Rb) formed by another bridging portion (Bb) closer to the other magnet (31b) of the first magnet pair (31a, 31b) than the mirror portion and a portion of the frame-shaped portion (FR) on the other side of the first magnet pair than the other bridging portion.

[0047] With this configuration, by using four magnets, it is possible to suppress crosstalk, in which the driving currents (i1, i1e) flowing through the first and second coils to rotate the frame in a direction of rotation about the second axis affect the force that rotates the frame in a direction of rotation about the first axis, and to swing the mirror portion in two axial directions.

[0048] Therefore, according to the present invention, it is possible to reduce the device size and manufacturing costs compared to the driving device described in Patent Document 1, which requires six magnets. EXAMPLES

[0049] FIG. 3A is a top view of a reflector scanner 300 according to a second embodiment of the present invention, and FIG. 3B is a side view of the reflector scanner 300 as viewed from the direction of the white arrow shown in FIG. 3A.

[0050] In the reflector scanner 300, the magnet 31b is mounted on the base 40 so that the polarity (e.g., S pole) of the surface of the magnet 31b facing the magnet 31a is opposite to the polarity (e.g., N pole) of the magnet 31b of the reflector scanner 200. That is, in the reflector scanner 300, the magnets 31a and 31b as the first magnet pair are mounted on the base 40 so that the opposing surfaces of the magnets 31a and 31b have the same polarity.

[0051] Furthermore, the reflector scanner 300 employs a power supply circuit 50A instead of the power supply circuit 50 included in the reflector scanner 200. Since the configuration other than the above is the same as that of the reflector scanner 200, a description of the other configuration will be omitted.

[0052] The operation of the reflector scanner 300 will now be described with reference to FIG.

[0053] 4 is a top view of the reflector scanner 300, in which the directions of the current, magnetic field, and Lorentz force flowing through each coil of the reflector scanner 300 at a given time are indicated by symbols or arrows.

[0054] The power supply circuit 50A supplies the driving current i2, which is an AC current, to the coil L3. Furthermore, the power supply circuit 50A supplies the driving current i1, which is an AC current, to the coil L1, and supplies the driving current i1e, which is an AC current in the same phase as the driving current i1, to the coil L2. As a result, at a certain point in time, the driving current i1 flows in the coil L1 in a clockwise direction as shown by the arrow in FIG. 4, and the driving current i1e flows in the coil L2 in a counterclockwise direction as shown by the arrow in FIG. 4.

[0055] Therefore, a first Lorentz force is applied to the frame portion FR at the left end of the frame 20 in response to the magnetic field B1 (indicated by a hollow arrow) generated by the magnet 31a and the drive current i1 (indicated by a black arrow) crossing the magnetic field B1. Furthermore, a second Lorentz force is applied to the frame portion FR at the right end of the frame 20 in response to the magnetic field B1e (indicated by a hollow arrow) generated by the magnet 31b and the drive current i1e (indicated by a black arrow) crossing the magnetic field B1e. At this time, the direction in which the first Lorentz force is applied and the direction in which the second Lorentz force is applied are opposite to each other, that is, when one of the first and second Lorentz forces is applied in the direction in which the front surface of the frame 20 faces, the other is applied in the direction in which the back surface of the frame 20 faces. As a result, a force (couple force) that rotates the frame 20 about the second axis J2 as the central axis is applied to the frame 20. Furthermore, since the drive currents i1 and i1e are alternating currents, the directions of the Lorentz forces acting on the right and left ends of the frame 20, respectively, are reversed at a period corresponding to the frequency of the alternating current while maintaining mutually opposite directions.

[0056] As a result, the frame 20 reverses the direction of rotation around the second axis J2 at a period corresponding to the frequency of the AC current, and the torsion bars T1a and T1b, receiving the inertial force, twist has the mirror portion MR oscillate in the direction of rotation around the second axis J2.

[0057] That is, in the reflector scanner 300, similarly to the reflector scanner 200, the mirror portion MR can be swung in the direction of rotation about the second axis J2.

[0058] Furthermore, the oscillation operation of the mirror section MR around the first axis J1 as the central axis by the driving current i2, the second magnet pair (32a, 32b), and the coil L3 is similar to that of the reflector scanner 200 described above, so a description thereof will be omitted.

[0059] 3A and 3B, the directions of the Lorentz forces acting on the bridging portions Ba and Bb due to the driving current i2 flowing through the coil L3 and the magnetic field b1 (b1e) from the magnet 31a (31b) are the same. Therefore, the Lorentz forces acting on both of the above-mentioned regions according to the driving current i2 flowing through the coil L3 do not become couple forces with respect to the rotational movement about the second axis J2.

[0060] Therefore, in the reflector scanner 300, the driving current i2 flowing through the coil L3 does not affect the rotational movement of the frame 20 about the second axis J2, that is, no crosstalk occurs. EXAMPLES

[0061] FIG. 5 is a top view of a reflector scanner 400 according to a third embodiment of the present invention.

[0062] The reflector scanner 400 has the same configuration as the reflector scanner 300, except that magnets 32aX and 32bX are used instead of the magnets 32a and 32b of the reflector scanner 300 shown in FIG. 3A, and coil L3A is used instead of coil L3.

[0063] Therefore, the following will mainly describe the configuration of the magnets 32aX and 32bX as the second magnet pair, and the coil L3A, and will explain the operation of the reflector scanner 400 employing this configuration.

[0064] 5, the coil L3A is wired in a loop or spiral shape on the frame portion of the frame 20 so as to surround the area on the surface of the frame 20 where the mirror portion MR and the coils L1 and L2 are arranged. One end of the wire constituting the coil L3A is connected to the power supply circuit 50A via wires provided on the surface of the torsion bar T2a, the support pillar 21a, and the base 40. The other end of the wire constituting the coil L3A is connected to the power supply circuit 50A via wires provided on the surface of the torsion bar T2b, the support pillar 21b, and the base 40.

[0065] As shown in FIG. 5, the magnets 32aX and 32bX are disposed outside the frame 20 on either side of a wiring section of the coil L3A that is routed along the direction of the first axis J1.

[0066] In the reflector scanner 400, as shown in FIG. 5, only the coils L1 and L2 are wired to the bridging portions Ba and Bb, and the coil L3A is not wired.

[0067] 5, the magnets 32aX and 32bX as the second magnet pair are longer in the direction along the first axis J1 than the magnets 32a and 32b shown in FIG. 3A. As a result, the wiring section of the coil L3A that crosses the magnetic field from the magnets 32aX and 32bX is longer than that of the reflector scanner 300 shown in FIG. 3A, and the Lorentz force is accordingly higher. Therefore, even if the amount of the drive current i2 is reduced, the mirror section MR can be reliably swung in the direction of rotation about the first axis J1, which makes it possible to reduce the power consumption and size of the entire device.

[0068] 5, the drive current i2 does not affect the rotation of the frame 20 about the second axis J2, i.e., no crosstalk occurs. In addition, on the surface of the frame 20, the direction of the Lorentz force generated in the region between the annular region Ra and the magnet 32aX (32bX) in response to the drive current i1 (i1e) is opposite to the direction of the Lorentz force generated in the region between the annular region Rb and the magnet 32aX (32bX). Therefore, the Lorentz force generated in the region between the annular region Ra and the magnet 32aX (32bX) and the Lorentz force generated in the region between the annular region Rb and the magnet 32aX (32bX) are offset with respect to the rotation direction of the frame 20 about the first axis J1. Therefore, the drive currents i1 and i1e which are responsible for the rotational movement of the frame 20 about the second axis J2 do not affect the rotational movement of the frame 20 about the first axis J1, that is, they do not cause crosstalk. EXAMPLES

[0069] FIG. 6A is a top view of a reflector scanner 500 according to a fourth embodiment of the present invention, and FIG. 6B is a side view of the reflector scanner 500 as viewed from the direction of the white arrow shown in FIG. 6A.

[0070] In addition, in the reflector scanner 500, the coils L1 and L2 are connected in parallel with each other, the coil L3B is used instead of the coil L3, and the power supply circuit 50B is used instead of the power supply circuit 50. Other configurations are the same as those of the reflector scanner 200 shown in Figures 1A and 1B.

[0071] Therefore, the wiring configuration of the coils L1, L2, and L3B in the reflector scanner 500 will be described.

[0072] 6A, in the reflector scanner 500, like the reflector scanner 200 shown in FIG 1A, the annular region Ra of the frame 20 includes a coil L1, a support column 21a, and a torsion bar T2a, and the annular region Rb includes a coil L2, a support column 21b, and a torsion bar T2b. Furthermore, the central region between the annular regions Ra and Rb includes a mirror section MR, torsion bars T1a, T1b, and a coil L3B.

[0073] Here, one end and the other end of the wiring forming the coil L1 are connected to the power supply circuit 50B via a pair of wires routed on the surface of the torsion bar T2a, inside the support pillar 21a, and inside the base 40. One end and the other end of the wiring forming the coil L2 are connected in parallel to the coil L1.

[0074] The coil L3B is wired in a loop or spiral shape between a pair of bridge parts Ba and Bb and the frame part FR so as to surround the mirror part MR, similar to the coil L3. However, one end and the other end of the wiring constituting the coil L3B are connected to the power supply circuit 50B via a pair of wirings installed inside the frame part FR on the outer periphery of the opening Ob, the surface of the torsion bar T2b, the support pillar 21b, and the base 40.

[0075] The power supply circuit 50B supplies a driving current i1 as an AC current to the coil L1, and also supplies a driving current i2 as an AC current to the coil L3B.

[0076] According to the configuration of the reflector scanner 500 shown in Figures 6A and 6B, the number of wires on the surfaces of the torsion bars T2a and T2b can be reduced from three to two, so that the width of these torsion bars T2a and T2b can be reduced. Furthermore, according to the configuration shown in Figures 6A and 6B, the number of wires of the coil L3B that crosses the magnetic field caused by the magnet 32a in the section close to the magnet 32a can be matched with the number of wires of the coil L3B that crosses the magnetic field caused by the magnet 32b in the section close to the magnet 32b. This makes it possible to achieve torque balance of the Lorentz forces that respectively promote clockwise rotation and counterclockwise rotation around the first axis J1 as the central axis. EXAMPLES

[0077] FIG. 7 is a top view of a reflector scanner 600 according to a fifth embodiment of the present invention.

[0078] 7, in the reflector scanner 600, the support 21a is connected to the bridge portion Ba of the pair of bridge portions (Ba, Bb) via a torsion bar T2a extending along the first axis J1. Also, the support 21b is connected to the bridge portion Bb of the pair of bridge portions (Ba, Bb) via a torsion bar T2b extending along the first axis J1.

[0079] The configuration other than the above is the same as that of the reflector scanner 300 shown in FIGS. 3A and 3B.

[0080] 7, the position of the connection point between the torsion bar T2a (T2b) and the frame 20 is closer to the second axis J2 than when the torsion bar T2a (T2b) is connected to the frame portion FR of the frame 20 as shown in FIG. 3A. This reduces the amount of displacement caused by the bending of the torsion bar T2a (T2b) when the frame 20 rotates about the second axis J2. This reduces the tensile stress applied to the torsion bar T2a (T2b) and the wiring on its surface, thereby extending the life of the torsion bar T2a (T2b) itself and reducing the probability of breakage of the wiring in the torsion bar T2a (T2b). This makes it possible to extend the life of the reflector scanner itself.

[0081] In the configuration shown in FIG. 7, the first drive current (i1, i1e) passed through coils L1 and L2 rotates the frame 20 around the second axis J2 as the central axis, and the second drive current (i2) passed through coil L3 rotates the frame 20 around the first axis J1 as the central axis.

[0082] However, two-axis rotational movement may be achieved by disposing only one system of single-wired coils on a frame 20A in which a support 21a (21b) is connected to a bridging portion (Ba, Bb) via a torsion bar T2a (T2b) as shown in FIG. 7, and supplying a current in which the above-mentioned first and second drive currents are superimposed to this single system of coils.

[0083] FIG. 8 is a top view of a reflector scanner 700, which has been created in consideration of the above points and is a modified example of the reflector scanner 600 shown in FIG.

[0084] 8, in the reflector scanner 700, a coil LQ consisting of a single wire is wired in a spiral or loop shape in each of the annular regions Ra and Rb of the frame 20A and in the central region including the bridging portions Ba and Bb. In this case, one end of the wire constituting the coil LQ is led out via a single wire wired in or on the surface of the torsion bar T2a, the support 21a, and the base 40. Furthermore, the other end of the wire constituting the coil LQ is led out via a single wire wired in or on the surface of the torsion bar T2b, the support 21b, and the base 40.

[0085] Furthermore, in the reflector scanner 700, instead of using four magnets (31a, 31b, 32a, 32b), a pair of magnets 33a and 33b are arranged facing each other on either side of the frame 20A on a third axis J3 extending diagonally across the frame 20A.

[0086] Here, the power supply circuit generates a drive current that is a superposition of the above-mentioned drive currents i1, i1e, and i2, and supplies this to one end and the other end of the wiring that forms the coil LQ, causing the frame 20A to rotate in a rotational direction around the two axes (J1, J2). [Explanation of symbols]

[0087] 20, 20A Frame 21a, 21b struts 31a, 31b First magnet pair 32a, 32b, 32aX, 32bX, 33a, 33b Second magnet pair 40 Foundations 50, 50A, 50B power circuit FR frame part L1, L2, L3, L3A, L3B, LQ coil MR mirror part T1a, T1b, T2a, T2b Torsion Bar

Claims

1. a frame having a frame-shaped portion extending along one surface and supported rotatably about a first axis along the one surface; a mirror portion connected to an inside of the frame via a first elastic member that stretches along a second axis along the first surface; a first drive unit that rotates the frame in a direction of rotation about the second shaft; a second drive unit that rotates the frame in a direction of rotation about the first shaft; Including, the frame has a pair of bridge portions extending on an inner side of the frame so as to sandwich the first axis therebetween and spanning between opposing portions of the frame across the second axis, The first drive unit includes: a first magnet pair disposed opposite to each other with the frame therebetween; a first coil that is wired in a ring shape along a first ring portion that is formed by a bridge portion that is closer to one of the magnets of the magnet pair than the mirror portion and a portion of the frame portion that is closer to the one side of the magnet pair than the first bridge portion; a second coil that is wired in a ring shape along a second ring portion that is formed by another bridging portion that is closer to the other magnet of the magnet pair than the mirror portion and a portion of the frame portion on the other side of the magnet pair than the other bridging portion, The second drive unit includes: The magnet pair; a third coil wired at least in a region between the pair of bridging portions of the frame-shaped portion.

2. a frame including a frame-shaped portion extending along one surface and a pair of bridge portions extending inside the frame-shaped portion so as to sandwich a first axis, the bridge portions spanning between portions facing each other across a second axis perpendicular to the first axis along the first surface, and the frame being supported rotatably around the first axis; a mirror portion connected to an inside of the frame via a first elastic member that stretches along the second axis; a first magnet pair disposed opposite to each other with the frame therebetween; A coil is wired to the frame-shaped portion of the frame and the pair of bridge portions; a first support pillar disposed inside a frame formed by a first annular portion that is formed by one of the set of bridging portions that is closer to one of the magnets of the magnet pair than the mirror portion is, and a portion of the frame-shaped portion that is closer to one of the magnet pair than the set of bridging portions; a second support pillar disposed inside a frame formed by a second annular portion formed by another bridging portion of the set of bridging portions that is closer to the other magnet of the magnet pair than the mirror portion is, and a portion of the frame-shaped portion on the other side of the magnet pair than the set of bridging portions; The first strut is connected to one of the pair of bridging portions via an elastic member that stretches along the first axis, A reflector scanner, characterized in that the second support is connected to the other of the pair of spanning portions via an elastic member that stretches along the first axis.

3. 3. The reflector scanner according to claim 1, wherein the pair of magnets are arranged opposite each other on either side of the frame on a third axis different from the first axis and the second axis, the third axis passing through the intersection of the first axis and the second axis along the first surface.

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