JP6670143B2 - Control device for oscillator device - Google Patents

Description

  The present invention relates to a control device for an oscillator device such as a MEMS mirror.

  Conventionally, as a two-dimensional optical scanning device, a technology for driving a MEMS (Micro Electro Mechanical Systems) mirror at high speed is known. For example, MEMS scanners with micro-mirrors often include a spring-mounted mirror plate that operates in one or more axes. The MEMS scanner scans a target (target region) by applying an electrostatic, electromagnetic, thermal, or piezoelectric force to the mirror plate. For example, Patent Literatures 1 and 2 disclose a technique in which a driving signal is supplied to a light source or a light deflecting device operable in two directions of an X axis and a Y axis to perform scanning in a spiral orbit.

U.S. Patent Application Publication No. 2015/281630 JP 2006-520022 Gazette

  For example, the MEMS scanner oscillates a mirror plate serving as an oscillating body at a high speed, and sequentially irradiates light to a region corresponding to a position at the time of oscillating (a tilt position from a reference position). When the mirror plate is swung, the driven portion is largely swung, that is, a large amplitude (for example, a scanning area) can be obtained by driving the mirror plate at a frequency corresponding to the resonance frequency. .

  On the other hand, in consideration of manufacturing a power-saving oscillator device, it is preferable that the oscillator device have a large Q value (Quality factor). For example, the Q value is determined by characteristics of a spring constituting the MEMS scanner. For example, in an oscillator device such as a MEMS scanner, the higher the Q value, the more stable the oscillation state (vibration state) can be obtained with power saving.

  On the other hand, since the responsiveness is reduced when the Q value is increased, the oscillator device having a high Q value has a characteristic that the time from the application of the driving force to the stabilization of the oscillating operation becomes longer. Here, when performing a drive that draws a helical trajectory (hereinafter, referred to as a spiral drive), it is necessary to periodically modulate the amplitude (eg, the swing angle) of the oscillator. Therefore, in consideration of performing the spiral drive of the oscillator device having a high Q value, a problem that stable oscillation modulation of the oscillator becomes difficult due to its low response is cited as an example.

  In a vibrating body device having a vibrating body such as a vibrating body such as a vibrating body device having a high Q value, it is preferable that stable drive control can be performed with power saving.

  The present invention has been made in view of the above points, and it is an object of the present invention to provide a control device of an oscillator device capable of performing amplitude modulation of the oscillator with power saving.

  According to a first aspect of the present invention, there is provided a control device for an oscillating device including an oscillating body that oscillates about at least one oscillating axis and a driving unit that drives the oscillating body, wherein a frequency of the oscillating body is higher than a resonance frequency of the oscillating body. A generator for generating a first signal for increasing the swing angle of the oscillator and a second signal for decreasing the swing angle, the signals being constant amplitude signals corresponding to the frequencies; And an output unit for outputting the first and second signals to the drive unit by alternately repeating the first and second periods for outputting the respective signals.

FIG. 2A is a schematic top view of the oscillator device according to the first embodiment and a control device thereof, and FIG. 2B is a cross-sectional view of the oscillator device according to the first embodiment. FIG. 2 is a block diagram illustrating a configuration of a control device according to the first embodiment. FIG. 6A is a diagram illustrating a waveform of an output signal of the control device according to the first embodiment, and FIG. 6B is a diagram illustrating a change in amplitude of a mirror plate around a swing axis AX in the oscillator device according to the first embodiment. FIG. (A) is a schematic operation explanatory view of the oscillator device according to the first embodiment, and (b) is a diagram illustrating a scanning locus of laser light by the oscillator device according to the first embodiment. FIG. 6 is a diagram illustrating an output example of another output signal of the control device of the oscillator device according to the first embodiment.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1A is a schematic top view of the oscillator device 10 and a control device 20 thereof according to the first embodiment. The oscillator device 10 is a device in which the oscillator 14 is swung by applying a driving force. In the present embodiment, the oscillating body 14 is a mirror plate, and the oscillating body device 10 is an optical scanner that drives the mirror plate 14 to perform optical scanning of an object. However, the oscillating body 14 is not limited to a mirror plate. For example, the oscillator device 10 may be an actuator having a movable part as the oscillator 14. In the following, a case where the oscillator 14 is a mirror plate will be described.

  The oscillator device 10 includes a base 11, an oscillator 12, a drive 13, and an oscillator 14. Further, in the present embodiment, the oscillator device 10 is configured such that the oscillator 14 swings around two swing axes (first and second swing axes) AX and AY that are orthogonal to each other. ing. Further, the drive unit 13 generates a swinging power (drive force) for swinging the swinging unit 12 and the swinging body 14. The control unit 20 is connected to the drive unit 13, and the drive of the drive unit 13 is controlled by the control device 20.

  In the present embodiment, the base unit 11 includes first and second base substrates B1 and B2. The oscillating portion 12 has a torsion bar (first torsion bar) SX having one end connected to the base portion 11 and a oscillating frame that is connected to the other end of the torsion bar SX and oscillates around the oscillating axis AX. MX, a torsion bar (second torsion bar) SY having one end connected to the swing frame MX, and a swing plate MY connected to the other end of the torsion bar SY and swinging around the swing axis AY. And A rocking body 14 is formed on the rocking plate MY.

  In the present embodiment, the torsion bars SX and SY include at least two bar-shaped elastic members (elastic bars) having elasticity in the circumferential direction. The torsion bars SX (elastic rods) are aligned in the length direction with the swing frame MX interposed therebetween, and the alignment direction is the direction of the swing axis AX of the swing frame MX. One end of the torsion bar SX is a fixed end fixed to the base 11, and the other end is connected to the outer peripheral portion of the swing frame MX. The torsion bars SY (elastic bars) are aligned in the length direction with the rocking plate MY interposed therebetween, and the alignment direction is the direction of the rocking axis AY of the rocking plate MY. Further, one end of the torsion bar SY is connected to the inner periphery of the swing frame MX, and the other end is connected to the outer periphery of the swing plate MY.

  The drive unit 13 includes a permanent magnet MG, a wiring (first wiring) WX routed along the outer periphery of the swing frame MX on the swing frame MX, and a swing plate MY on the swing plate MY. And a wiring (second wiring) WY routed along the outer periphery. In this embodiment, the drive unit 13 electromagnetically swings the swing unit 12 and the swing body 14 by a magnetic field generated by the permanent magnet MG and an electric field generated by applying a current to the wirings WX and WY. An electromagnetic force (driving force) to be generated is generated.

  In this embodiment, the permanent magnet MG is provided outside the second base substrate B2, and has a plurality of magnet pieces arranged side by side with the swing portion 12 interposed therebetween. In the present embodiment, two magnet pieces are arranged along each of the swing axes AX and AY, that is, a total of four magnet pieces are arranged. When a current flows through the wiring WX, the interaction between the electric field generated in the wiring WX and the magnetic field generated by the magnet pieces of the permanent magnet MG arranged in the axial direction of the oscillation axis AY causes the torsion bar SX to twist in the circumferential direction. , The swing frame MX swings around the swing axis AX. Similarly, the torsion bar SY is twisted by the electric field generated by the current flowing through the wiring WY and the magnetic field generated by the magnet pieces of the permanent magnet MG arranged in the axial direction of the swing frame AX, and the swing plate MY moves around the swing axis AY. Rocks. In the present embodiment, the resonance frequency of the swing unit 12 around the swing axis AX is equal to the resonance frequency of the swing unit AY around the swing axis AY.

  In this embodiment, the mirror plate as the rocking body 14 has a flat plate shape and has a central axis CA orthogonal to the rocking axes AX and AY. The oscillating plate MY mounts the oscillating body 14, the oscillating frame MX is arranged to surround the oscillating plate MY, and the base portion 11 is arranged to surround the oscillating frame MX. The oscillating portion 12 and the oscillating body 14 are arranged rotationally symmetrically with respect to the center axis CA of the oscillating body 14.

  FIG. 1B is a cross-sectional view of the oscillator device 10. FIG. 1B is a cross-sectional view taken along the line VV in FIG. In the present embodiment, the oscillator device 10 is a MEMS (Micro Electro Mechanical Systems) device. Specifically, first, as shown in FIG. 1B, the base portion 11 includes a first base substrate B1 having a concave portion, and a second base plate having a flat plate shape fixed to the first base substrate B1. And a substrate B2. For example, the first base substrate B1 is formed from a resin material, and the second base substrate B2 is formed from an SOI (Silicon on Insulator) wafer.

  Further, the swing part 12 (the swing frame MX, the swing plate MY, and the torsion bars SX and SY) is formed of a second base substrate B2 (SOI wafer) formed by processing the second base substrate B2 (SOI wafer). Part. Further, the oscillating portion 12 and the oscillating body 14 are supported (suspended) by the second base substrate B2 on the concave portion of the first base substrate B1. In addition, the swing body 14 is suspended on the swing unit 12 that functions as a two-axis gimbal. Note that a portion of the second base substrate B2 outside the torsion bar SX functions as a support frame that supports the swing unit 12 and the swing body 14 so as to be able to vibrate (swing).

  Further, the mirror plate as the oscillator 14 is formed in a plate shape (film shape) on a portion of the second base substrate B2 functioning as the oscillator plate MY. The permanent magnet MG is formed outside the portion of the second base substrate B2 functioning as the torsion bar SX, in this embodiment, on the first base substrate B1. In the present embodiment, the swing unit 12 swings in the thickness direction of the second base substrate B2. Further, the swinging body 14 swings so as to be inclined with respect to the second base substrate B2 (base portion 11) with one point on the central axis CA as the swing center.

  As described above, the oscillator device 10 includes the oscillator 14 that swings around the oscillation axes AX and AY, and the drive unit 13 that drives the oscillator 14. Further, the oscillator device 10 is provided with a control device 20 for controlling the driving of the oscillator device 10. Further, in the present embodiment, the rocking body 14 is formed on the rocking section 12 which rocks by the driving section 13, and the rocking section 14 rocks by the rocking section 12 rocking by the driving section 13. . The control circuit 20 is connected to the drive unit 13.

  FIG. 2A is a block diagram illustrating a configuration of the control device 20. The control device 20 generates a signal for driving the oscillator device 10 and supplies the signal to the oscillator device 10. The control device 20 includes a reference signal generation unit 21, a swing signal generation unit (generation unit) 22 that generates a signal for swinging the oscillator device 10, and an output unit 23 that outputs the signal to the drive unit 13. Have. In the present embodiment, the control circuit 20 includes a switching signal generation unit 24 that generates a switching signal for switching a signal output from the output unit 23, and a swing angle detection unit 25 that detects a swing angle of the swing body 14. Having.

  The reference signal generation unit 21 generates a reference signal RS serving as a reference of the swing signal, and supplies the reference signal RS to the swing signal generation unit 22. The reference signal generation unit 21 generates a periodic signal as the reference signal RS. The reference signal RS is, for example, a sine wave and a sawtooth wave.

  The swing signal generator 22 includes a first swing signal (first signal) S1 for increasing the swing angle of the swing body 14 with respect to the swing axis AX, and a swing angle of the swing body 14 with respect to the swing axis AX. Has a first generation unit 22A that generates a second swing signal (second signal) S2 that reduces the noise. Further, the swing signal generation unit 22 includes a third swing signal S3 for increasing the swing angle of the swing body 14 with respect to the swing axis AY, and a third swing signal S3 for decreasing the swing angle of the swing body 14 with respect to the swing axis AY. And a second generation unit 22B that generates the fourth swing signal S4.

  The first generator 22A includes a first phase shift circuit SF1 that shifts the phase of the reference signal RS by 90 degrees to generate a shift reference signal RSS, and a second phase that shifts the phase of the shift reference signal RSS by 180 degrees. The shift circuit includes a shift circuit SF2 and first and second amplifier circuits AM1 and AM2 connected to output terminals of the first and second phase shift circuits SF1 and SF2, respectively. The first generator 22A supplies the signals amplified by the first and second amplifier circuits AM1 and AM2 to the output unit 23 as first and second swing signals S1 and S2, respectively.

  The second generator 22B includes a third phase shift circuit SF3 that shifts the phase of the reference signal RS by 180 degrees, and a third phase shift circuit SF3 and a third phase shifter connected to the output terminals of the reference signal generator 21. And fourth amplifier circuits AM3 and AM4. The second generator 22B supplies the signals amplified by the third and fourth amplifier circuits AM1 and AM2 to the output unit 23 as first and second swing signals S3 and S4, respectively.

  The output unit 23 selects the first and second swing signals S1 and S2 and outputs the selected signal as the first output signal OS1, and the third and fourth swing signals S3 and S4. And outputs a second output signal OS2.

  The first output signal OS1 is a control signal for controlling the swing angle (amplitude) of the oscillator 14 with respect to the swing axis AX, and the second output signal OS2 is the swing of the oscillator 14 with respect to the swing axis AY. This is a control signal for controlling the angle (amplitude). In this embodiment, the first output signal OS1 is supplied to the wiring WX, and the second output signal OS2 is supplied to the wiring WY.

  The reference signal generator 21 includes, for example, an oscillator. Each of the first to third phase shift circuits SF1 to SF3 includes, for example, a delay circuit. Each of the first to fourth amplifier circuits AM1 to AM4 includes, for example, a multiplication circuit. The first and second output units 23A and 23B include, for example, a selector. The first output unit 23A has three input terminals, the first and second input terminals receive first and second swing signals S1 and S2, and the third input terminal is grounded. Have been. The second output unit 23B has three input terminals, the first and second input terminals receive third and fourth swing signals S3 and S4, and the third input terminal is grounded. Have been.

  Further, the control device 20 includes a switching signal generation unit 24 that controls the output signals OS1 and OS2 in the output unit 23, that is, generates switching signals SS1 and SS2 for switching each swing signal, respectively. The switching signal SS1 is supplied to a first output unit 23A, and the switching signal SS2 is supplied to a second output unit 23B. That is, the output operation of the output unit 23 is controlled by the switching signals SS1 and SS2.

  The control device 20 includes a swing angle detection unit (hereinafter, simply referred to as a detection unit) 25 that detects a swing angle of the swing body 14. The detection unit 25 detects the tilt angle of the rocking frame MX and the rocking plate MY, for example, to detect the rocking angle of the rocking body 14 with respect to each of the rocking axes AX and AY from the non-driving position. The detection unit 25 includes, for example, a first detection unit (not shown) including a resistor formed on the torsion bar SX and a measurement circuit for measuring an electric resistance value of the resistor, And a second detector (not shown) for measuring the electric resistance value of the resistor.

  FIG. 3A is a diagram illustrating a waveform of the output signal OS1 output from the first output unit 23A of the output unit 23. In the figure, the horizontal axis represents time, and the vertical axis represents the amplitude of the output signal OS1. The generation operation of the swing signal generation unit 22 and the output operation of the output unit 23 will be described with reference to FIG. First, the swing signal generation unit 22 (first generation unit 22A) has a frequency corresponding to the resonance frequency of the oscillator 14 (for example, an integral multiple) and a first and second oscillation signal S1 having a constant amplitude. And S2 are generated.

  The output unit 23 (first output unit 23A) outputs the first swing signal S1 in the first period P1, and outputs the second swing signal S2 in the second period P2. Further, in the present embodiment, the output unit 23 instructs the drive unit 13 to perform a first period P1, a second period P2, and a non-signal period (third period) P3 for stopping signal output. Is repeated in this order. More specifically, the first output unit 23A changes the connection position of its input terminal to the output terminal of the first amplifier circuit AM1, the output terminal of the second amplifier circuit AM2, and the ground terminal by the switching signal SS1, Is switched repeatedly in this order.

  In the present embodiment, the first and second periods P1 and P2 are periods of substantially the same length. More specifically, the first period P1 and the period from the start of the second period P2 to the end of the no-signal period P3 (period P2 + P3) have the same length. On the other hand, each of the first period P1 and the second period P2 is sufficiently longer than the no-signal period P3.

  The non-signal period P3 is started when the swing angle of the swing body 14 is equal to or less than a predetermined angle, for example, at a reference position when not driven (when the swing angle is 0 degree). That is, the output unit 23 is configured to apply a fixed potential (for example, a ground potential) to the driving unit 13 for a predetermined period when the rocking angle of the rocking body 14 becomes equal to or smaller than the predetermined angle after the second period P2. ing. The non-signal period P3 (application of the ground potential) starts based on the detection signal of the detection unit 25.

  FIG. 3B is a diagram illustrating a change in a swing angle of the swing body 14 with respect to the swing axis AX that has been swung by the output signal OS1. In the figure, the horizontal axis indicates time, and the vertical axis indicates the swing angle (amplitude) of the swing body 14 around the swing axis AX. First, as described above, the swing signal S1 is supplied to the oscillator 14 such that the swing angle of the oscillator 14 increases in the first period P1. However, when the rocking body 14 has a high Q value, the desired rocking state is not reached immediately after the signal is supplied due to its low response. Therefore, as shown in FIG. 3B, in the first period P1, the oscillator 14 receives a driving force at a frequency corresponding to the resonance frequency, and while gradually increasing the oscillation angle, that is, the amplitude, of the oscillator. Perform the action.

  On the other hand, after the first period P1, as a second period P2, a driving force such that the rocking angle of the rocking body 14 becomes small. In this embodiment, a rocking signal S2 having a phase opposite to that of the rocking signal S1. Is supplied to the oscillator 14. Specifically, the rocking body 14 is configured such that after the amplitude increases in the first period P1 and reaches the rocking state with a predetermined amplitude, the rocking is suppressed in the second period P2. Receive driving force. Therefore, the rocking body 14 rocks in the second period P2 such that the rocking angle, that is, the amplitude becomes small.

  Further, in the present embodiment, after the second period P2, that is, after the swing angle of the swing body 14 is reduced, the control device 20 performs a period in which the swing signals S1 and S2 are not supplied to the swing body 14, that is, The process shifts to the non-signal period P3. In the non-signal period P3, since the ground potential is applied to the driving unit 13 of the oscillator 14, no driving force is generated. After the third period P3, the output unit 23 performs signal output by repeating the first to third periods P1 to P3.

  Note that the frequencies of the first and second swing signals S1 and S2 and the third and fourth swing signals S3 and S4, which will be described later, are based on the resonance frequencies of the swing body 14 around the swing axes AX and AY. They need to be roughly matched. On the other hand, the amplitudes of the first and second swing signals S1 and S2 and the second period P2 can be adjusted according to the Q value of the swing body 14. For example, the amplitude of the first swing signal S1 up to a desired swing angle is calculated based on the Q value of the swing body 14, and the amplitude of the first swing signal S1 and the amplitude of the first swing signal S1 are calculated based on the calculation result. 2, the length of the period P2 can be set.

  As described above, the control device 20 controls the first swing signal (the first swing signal (the first swing signal) that increases the swing angle of the swing body 14, which is a signal whose frequency corresponds to the resonance frequency of the swing body 14 and whose amplitude is constant. ), A swing signal generator 22 for generating a second swing signal (second signal) S2 for decreasing the swing angle of the swing body 14, and a first swing signal S1. An output unit that outputs the first and second swing signals S1 and S2 to the driving unit 13 by repeating the first period P1 and the second period P2 that outputs the second swing signal S2; . Therefore, the amplitude modulation of the oscillator 14 can be performed easily and reliably.

  Further, the second output unit 23B of the output unit 23 outputs the third and fourth swing signals S3 and S4 to the driving unit 13 during the first and second periods P1 and P2, respectively. Therefore, the waveform of the output signal OS2 output from the second output unit 23B of the output unit 23 is similar to the output signal OS1 shown in FIG. 3A except that the phase is shifted by 90 degrees. The waveform is shown. The change of the swing angle of the swing body 14 with respect to the swing axis AY caused by the output signal OS2 is similar to the change of the swing angle with respect to the swing axis AX shown in FIG.

  In this embodiment, the rocking body 14 rocks about first and second rocking axes AX and AY which are orthogonal to each other. The generating unit 22 oscillates the oscillating body 14 with respect to the first oscillating axis AX and the first and second signals S1 and S2, and oscillates the oscillating body 14 with respect to the second oscillating axis AY. Third and fourth signals S3 and S4 to be generated are generated.

  Further, the first and second signals S1 and S2 are signals having a constant amplitude and opposite phases to each other corresponding to a common resonance frequency around the first and second oscillation axes AX and AY of the oscillator 14. It is. The third and fourth signals S3 and S4 have a frequency corresponding to the common resonance frequency, have a constant amplitude, and have a phase of 90 degrees with the first and second signals S1 and S2, respectively. Different signals.

  The control device 20 supplies the similar output signals OS1 and OS2 to the swing axes AX and AY of the swing body 14, respectively, so that the swing body 14 is modulated with respect to the modulated angles (with respect to the swing axes AX and AY). Swing with amplitude). By swinging the swinging body 14 in this manner, it is possible to easily perform the spiral drive of the swinging body 14.

  FIG. 4A is a schematic operation explanatory view of the MEMS mirror as the oscillator device 10. The oscillator device 10 is configured to reflect the input light L1 from the light source LS toward the target object OB by the mirror plate 14. The mirror plate 14 is driven by the control device 20. The oscillating device 10 oscillates the mirror plate 14 to irradiate the illuminated area A1 to be scanned with the object OB with the reflected light L2 and perform optical scanning of the illuminated area A1. For example, when the oscillator device 10 is mounted on an imaging device, the irradiation area A1 of the target object OB is an imaging region.

  FIG. 4B is a diagram schematically illustrating a driving locus of the mirror plate 14 by the control device 20. FIG. 4B is a diagram schematically showing an optical scanning trajectory of the irradiation area A1 by the MEMS mirror as the oscillator device 10, that is, an irradiation trajectory of the reflected light L2 in the irradiation area A1 of the object OB. In the present embodiment, a case where the irradiated area A1 is a planar area will be described.

  As shown in FIG. 4B, the reflected light L2 is applied to the irradiation area A1 so as to draw a spiral trajectory. That is, the oscillator device 10 swings the mirror plate 14 by spiral driving. Therefore, the MEMS mirror as the oscillator device 10 scans the irradiation area A1 by spiral scanning.

  In the spiral driving (spiral scanning), for example, the tilt angle (swing angle) from the central axis CA when the mirror surface of the mirror plate 14 is not driven is modulated, and the mirror plate 14 is moved to one point on the central axis CA. Can be realized by driving so as to rotate around the rotation center.

  For example, the above-described method of controlling the oscillator device 10 by the control device 20 can provide a large effect (easiness of driving and power saving) when the oscillator 14 having a high Q value is spirally driven. The Q value of the oscillator 14 is determined by the material and shape of the oscillator 14, the configuration of the oscillator 12, and the like. For example, if the resonance frequency of the oscillator 14 with respect to the oscillation axes AX and AY is f, and the period from when the oscillator 14 returns from the rest state to the rest state through the oscillation state is T, the resonance frequency of the oscillator 14 Is more effective when the Q value of Q satisfies Q> 4.5 × f × T. When the Q value of the oscillating body 14 is Q ≦ 4.5 fT, the same oscillating drive can be performed by simply supplying the oscillating body 14 (the driving unit 13) with an oscillating signal whose amplitude is modulated. It is confirmed by simulation that it is possible.

  Further, in the present embodiment, the case where the driving unit 13 generates the electromagnetic force as the driving force for driving the swing unit 12 and the swing body 14 has been described, but the configuration of the driving unit 13 is not limited thereto. For example, the drive unit 13 may be configured to generate an electrostatic force or a piezoelectric force by receiving a control signal (for example, the swing signals S1 and S2) from the control device 20.

  Also, the case has been described where the first and second swing signals S1 and S2 are sinusoidal signals having the same amplitude and opposite phases, but the configuration of the first and second swing signals S1 and S2 is as follows. It is not limited to this. The first and second swing signals S1 and S2 only need to have a constant amplitude, and the first swing signal S1 is a signal for increasing the swing angle of the swing body 14, and the second swing signal The signal S2 may be a signal that reduces the swing angle of the swing body 14. Further, the case where the first and second periods P1 and P2 have substantially the same length has been described, but the first and second periods may have different lengths. The same applies to the third and fourth swing signals S3 and S4.

  Further, in the present embodiment, the case where the control device 20 includes the reference signal generation unit 21 and the swing angle detection unit 25 has been described, but the reference signal generation unit 21 and the swing angle detection unit 25 are provided outside the control device 20. May be provided. Further, for example, when the swing angle can be estimated, it is not necessary to provide the swing angle detection unit 25.

  Also, a case has been described where the swing signal generation unit 22 has first and second generation units 22A and 22B, and the output unit 23 has first and second output units 23A and 23B. The configurations of the generation unit 22 and the output unit 23 are not limited to this. For example, the oscillator device 10 may be configured to swing the oscillator 14 around only one swing axis, for example, only the swing axis AX. In this case, the swing signal generator 22 only needs to have the first generator 22A, and the output unit 23 only needs to have the first output unit 23A. That is, the swing signal generation unit 23 only needs to generate the first and second swing signals S1 and S2, and the output unit 23 selectively outputs the first and second swing signals S1 and S2. What is necessary is just to be comprised.

  FIG. 5 is a diagram illustrating another example of the output signal OS1 output from the first output unit 23A of the output unit 23. As shown in FIG. 5, the output unit 23 outputs the first and second swing signals S1 and S2 by repeating the first and second periods P2 alternately without shifting to the above-described no-signal period P3. It may be configured to do so.

  That is, the output unit 23 repeats the first period P1 during which the first swing signal S1 is output and the second period P2 during which the second swing signal S2 is output, and outputs the first and second signals to the drive unit 13. It suffices if it is configured to output the two swing signals S1 and S2. In this case, there is no need to provide the detection unit 25, and the first and second periods P1 and P2 may be repeated periodically.

  Considering that the swing angle (that is, the amplitude) of the swing body 14 is accurately controlled, it is preferable that the swing angle of the swing body 14 be 0 degrees after the second period P2. In this case, after the second period P2, the detection unit 25 detects the swing angle of the swing body 14, and when the swing angle of the swing body 14 becomes equal to or smaller than a predetermined value, the output unit 23 outputs the second swing angle. After the period P2, it is preferable to shift to the non-signal period P3 and stop the output of the swing signal.

  As described above, in the present embodiment, the control device 20 includes the swing body 14 that swings around at least one swing axis (swing axis AX) and the drive unit 13 that drives the swing body 14. The control of the oscillator device 10 is performed. In addition, the control device 20 controls the first signal S1 that increases the swing angle of the oscillator 14 and the first signal S1 that is a signal having a constant amplitude corresponding to the resonance frequency of the oscillator 14 and the oscillation of the oscillator 14. The driving section 22 generates the second signal S2 for decreasing the angle, and repeatedly drives the first period P1 for outputting the first signal S1 and the second period P2 for outputting the second signal S2. The output unit 23 outputs the first and second signals S1 and S2 to the unit 13. Therefore, for example, the rocking body 14 having a high Q value can be rocked while easily performing amplitude modulation. Accordingly, it is possible to provide the control device 20 of the oscillator device 10 and the control method of the oscillator device 10 that can perform the amplitude modulation of the oscillator 14 with power saving.

Reference Signs List 10 Oscillator device 13 Drive unit 14 Oscillator AX, AY Oscillator shaft 20 Controller 22 Oscillation signal generator (generation unit)
23 output unit 25 swing angle detection unit (detection unit)
S1 First swing signal (first signal)
S2 Second swing signal (second signal)

Claims (7)

A control device for an oscillator device, comprising: an oscillator that swings around at least one oscillation axis; and a driving unit that drives the oscillator.
A signal having a constant amplitude corresponding to a resonance frequency of the oscillating body is generated, and a first signal for increasing the oscillating angle of the oscillating body and a second signal for decreasing the oscillating angle are generated. A generating unit;
A control unit comprising: an output unit that outputs the first and second signals to the driving unit by alternately repeating first and second periods for outputting the first and second signals, respectively. apparatus.   The control device according to claim 1, wherein the second signal has an opposite phase to the first signal.   The control device according to claim 1, wherein the output unit repeats the first period, the second period, and a third period in which signal output is stopped in this order. . A detecting unit that detects a swing angle from a reference position when the swing body is not driven,
4. The output unit, when the swing angle of the swing body from the reference position becomes equal to or smaller than a predetermined angle, shifts to the third period and stops outputting a signal. 5. The control device according to claim 1.   The control device according to any one of claims 1 to 4, wherein the first and second periods are periods of substantially the same length.   Assuming that the resonance frequency of the oscillator is f and the period from the stationary state of the oscillator to the stationary state through the oscillation state is T, the Q value of the oscillator is Q> 4.5f × T. The control device according to claim 1, wherein the relationship is satisfied. The rocking body rocks about first and second rocking axes orthogonal to each other,
The generator includes the first and second signals for swinging the oscillator about the first swing axis, and a second signal for swinging the oscillator about the second swing axis. Generating third and fourth signals;
The first and second signals are signals having constant amplitudes and opposite phases, each corresponding to a common resonance frequency around the first and second oscillation axes of the oscillator,
The third and fourth signals are signals whose frequencies correspond to the common resonance frequency, each has a constant amplitude, and each has a phase different from the first and second signals by 90 degrees. The control device according to any one of claims 1 to 6, characterized in that:

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