JP2005181576A - Two-dimensional optical scanner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-dimensional optical scanner in which a two-dimensional plane is scanned. <P>SOLUTION: The optical scanner is provided with: an inner frame 34 furnished in a supporting frame 31 and having a magnet face formed on the back face of the frame; a pair of torsion springs 38 and 39 supporting both ends of the inner frame 34 on the supporting frame 31; a mirror plate 37 furnished in the inner frame 34 and forming a mirror face on the front surface and forming a magnet face on the back face; a pair of torsion springs 40 and 41 arranged in the direction orthogonal to the aligned direction of the pair of torsion springs 38 and 39 and supporting both ends of the mirror plate 37 on the inner frame 34; and a magnetic field generation means which generates a magnetic field orthogonal to the magnet face formed on the the back face of the inner frame 34 and the back face of the mirror plate 37. The magnet on the back face of the inner frame 34 and the magnet on the back face of the mirror plate 37 are magnetized in a direction inclined to the aligned direction of the pair of torsion springs 38 and 39 and the aligned direction of the pair of torsion springs 40 and 41, and the mirror plate 37 is tilted in two-dimensional directions with the magnetic field generated by the magnetic field generation means around the respective torsion axes which are the pair of torsion springs 38 and 39 and the pair of torsion springs 40 and 41, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical scanner that scans a two-dimensional plane.

  A mirror part is formed on one surface and both ends of a scanning mirror having a magnet film formed on the other surface are supported, and a coil is arranged on the side of the scanning mirror facing the magnet film forming surface to make the scanning mirror one-dimensional. There is known a one-dimensional optical scanner which is driven in a continuous manner (for example, see Patent Document 1).

Prior art documents related to the invention of this application include the following.
Japanese Patent Application Laid-Open No. 06-082711

  However, since the conventional optical scanner described above does not scan a two-dimensional plane, for example, it emits laser light or radio waves in a two-dimensional direction in front of the vehicle and receives reflected light from an object existing in front of the vehicle. Thus, it cannot be used in a vehicle radar device that detects the size of an object and the distance to the object.

  The present invention is provided on the inner side of the support frame, provided on the inner frame with a magnet surface on the back surface, a pair of torsion springs X1 and X2 for supporting both ends of the inner frame on the support frame, and on the inner side of the inner frame. A pair of mirror plates having a mirror surface formed on the front surface and a magnet surface formed on the back surface and a pair of torsion springs X1 and X2 arranged in a direction orthogonal to the arrangement direction and supporting both ends of the mirror plate on the inner frame And torsion springs Y1 and Y2 and a magnetic field generating means for generating a magnetic field perpendicular to the magnet surface formed on the inner frame and the back surface of the mirror plate, and the magnets on the back surface of the inner frame and the mirror plate are connected to a pair of torsion springs Magnetized in a direction inclined from the alignment direction of X1 and X2 and the alignment direction of the pair of torsion springs Y1 and Y2, and using the pair of torsion springs X1 and X2 and the pair of torsion springs Y1 and Y2 as a torsion axis , Magnetic field of magnetic field generation means Tilting more to the mirror plate in a two-dimensional direction.

  According to the present invention, a small and inexpensive two-dimensional optical scanner can be provided.

  An embodiment in which the two-dimensional optical scanner of the present invention is applied to a vehicle laser radar device will be described.

<< First Embodiment of the Invention >>
FIG. 1 is a block diagram showing the configuration of the first embodiment. The laser diode 1 emits laser light having a predetermined divergence angle. The laser diode drive circuit 2 drives the laser diode 1 and emits laser light from the laser diode 1 in accordance with a light emission command from the control circuit 3. The laser light emitted from the laser diode 1 enters the scanner unit 4, and the laser light is scanned on a two-dimensional plane by the tilt of the scanner unit 4. The laser light reflected by the mirror part (details will be described later) of the scanner part 4 enters the reflecting mirror 5 and is totally reflected by the reflecting mirror 5 so that the optical axis is directed forward of the vehicle.

  The photodetector 6 receives the laser beam reflected by the object 7 in front of the vehicle. The light receiving circuit 8 shapes the light receiving signal output from the photo-detector 6 into a light receiving pulse signal and outputs the light receiving pulse signal to the control circuit 3. The control circuit 3 is the time from the laser light emission by the laser diode 1 to the light reception by the photodetector 6, that is, the laser light is emitted from the laser diode 1 and reaches the object 7, and the laser light reflected by the object 7 is photo-photographed. The propagation delay time until returning to the detector 6 is measured, and the distance and direction to the object 7 are detected based on the propagation delay time and the mirror section angle of the scanner section 4.

  The amplifiers 9 to 11 amplify torsion angle signals and bending angle signals from three angle detectors (described later in detail) installed in the scanner unit 4. The drive circuits 12 to 14 perform feedback control so that the twist angle and the bending angle from the three detected angle values of the scanner unit 4 coincide with the deflection angle command values from the control circuit 3, and the coil 15 (details will be described later). ) To output the scanner drive signal. The amplifiers 16 to 18 amplify the scanner drive signals of the drive circuits 12 to 14 and energize the coil 15.

  FIG. 2 is a cross-sectional view showing the shape of the scanner unit. In the scanner unit 4, a silicon plate 23 is installed on a base plate 21 via a spacer 22. The base plate 21 and the spacer 22 are hollow, and the coil 15 is housed in the hollow portion to generate a magnetic field in the direction A in the figure, that is, in the direction orthogonal to the silicon plate 23. Reference numerals 15 a and 15 b are power supply terminals of the coil 15.

  FIG. 3 is a top view showing the structure of the silicon plate 23. The silicon plate 23 has slits formed by micromachining and is divided into three concentric rectangles. The outermost frame is a support plate 31, which is attached to the spacer 22 of the scanner unit 4 shown in FIG. A frame 34 is formed on the inner side of the support plate 31 with the slits 32 and 33 interposed therebetween, and a mirror portion 37 is further formed on the inner side of the frame 34 with the slits 35 and 36 interposed therebetween. A mirror surface is formed on the surface of the mirror portion 37.

  The support plate 31 and the frame 34 are connected via a pair of torsion springs 38 and 39 in the left-right direction, and the frame 34 and the mirror part 37 are connected via a pair of torsion springs 40 and 41 in the vertical direction. The frame 34 and the mirror part 37 can be tilted independently of the support plate 31. The alignment direction of the pair of torsion springs 38 and 39 and the alignment direction of the pair of torsion springs 40 and 41 are orthogonal to each other. The torsion springs 40 and 41 can be tilted in a two-dimensional direction with respect to the support plate 31 with a torsion shaft.

  In the vicinity of the torsion spring 39, an angle detector 42 for detecting the torsion angle of the torsion spring 39, that is, the tilt angle of the frame 34 with the pair of torsion springs 38 and 39 as the torsion shaft is installed. Further, an angle detector 43 that detects the torsion angle of the torsion spring 40, that is, the tilt angle of the mirror portion 37 with the pair of torsion springs 40 and 41 as the torsion axis, is installed in the vicinity of the torsion spring 40. Further, an angle detector 44 that detects the bending angle of the torsion spring 41, that is, the tilt angle of the mirror portion 37 with the arrangement direction of the pair of torsion springs 38 and 39 as an axis, is installed in the vicinity of the torsion spring 41. Piezoresistive elements are used for these angle detectors 42-44. The angle signals of the angle detectors 42 to 44 are guided to the contact pads 45 on the support plate 31 via the wiring pattern (not shown) on the upper surface of the frame 34 and the support plate 31, and the corresponding amplifier 9 via the signal wiring. To 11.

  On the back surface of the silicon plate 23, a magnetic thin film made of a ferromagnetic material is formed. The magnetic thin film is formed, for example, by laminating a plurality of composite materials of a ferromagnetic material such as samarium or terbium and a weak magnetic material such as iron or nickel by a thin film forming method such as sputtering.

  The magnetic thin film magnetic poles are formed in the direction of the arrow C in the figure inclined 45 degrees from the direction in which the pair of torsion springs 38, 39 in the left-right direction and the direction in which the pair of torsion springs 40, 41 in the vertical direction are aligned, As shown, it has an N pole and an S pole. The pair of torsion springs 38 and 39 in the left and right direction has a torsional resonance frequency of 250 Hz, and the pair of torsion springs 40 and 41 in the up and down direction has a torsional resonance frequency of 50 Hz. Further, the pair of torsion springs 40 and 41 in the vertical direction has a bending resonance frequency of 2 kHz.

  When an alternating magnetic field of 250 Hz is generated in the direction perpendicular to the silicon plate 23 by the coil 15 disposed on the back surface of the silicon plate 23, the pair of torsion springs 38 and 39 in the left-right direction twist and resonate in the E direction in the figure. Arise.

  In order to make the explanation easier to understand, consider the moment when a coil 15 generates a stationary magnetic field of N pole on the back surface (magnetic thin film forming surface) side of the silicon plate 23 and S pole on the front surface (mirror surface forming surface) side. . Focusing on the torsional resonance of the pair of torsion springs 38 and 39 in the left-right direction, the a part and e part in the figure are magnetized to the S pole by the magnetic moment of the vertical component Cβ of the magnetic pole C. Repels the magnetic field and moves to the surface side of the silicon plate 23 (the front side of FIG. 3). Similarly, the b part and the f part in the figure are magnetized to the N pole by the magnetic moment of the vertical component Cβ of the magnetic pole C, so that they are attracted by the magnetic field of the coil 15 (see FIG. Move to the back of the 3rd page. Therefore, the frame 34 and the mirror part 37 tilt in the direction of arrow E in the drawing with the pair of torsion springs 38 and 39 in the left-right direction as the torsion axis.

  When a 50 Hz alternating magnetic field is generated by the coil 15 in a direction perpendicular to the silicon plate 23, the pair of torsion springs 40 and 41 in the vertical direction generate torsional resonance vibration in the direction D shown in the figure.

  In order to make the explanation easy to understand, let us consider a moment when a stationary magnetic field of N pole on the back side of the silicon plate 23 and S pole on the front side is generated by the coil 15. When attention is paid to the torsional resonance of the pair of torsion springs 40 and 41 in the vertical direction, the portion c in the figure is magnetized to the S pole by the magnetic moment of the horizontal component Cα of the magnetic pole C. It repels and moves to the surface side of the silicon plate 23 (the front side of FIG. 3). Similarly, the portion d in the figure is magnetized to the N pole by the magnetic moment of the left-right direction component Cα of the magnetic pole C, so that it is attracted by the magnetic field of the coil 15 and the back side of the silicon plate 23 (on the paper surface of FIG. 3). Move to the back side. Therefore, the mirror portion 37 tilts in the direction of the arrow D in the figure with the pair of torsion springs 40 and 41 in the vertical direction as the torsion axis.

  Further, when an alternating magnetic field of 2 kHz is generated by the coil 15 in a direction perpendicular to the silicon plate 23, the pair of torsion springs 40 and 41 in the vertical direction generate bending resonance vibration in the E direction in the figure.

  In order to make the explanation easy to understand, let us consider a moment when a stationary magnetic field of N pole on the back side of the silicon plate 23 and S pole on the front side is generated by the coil 15. When attention is paid to the bending resonance of the pair of torsion springs 40 and 41 in the vertical direction, the portion e in the figure is magnetized to the S pole by the magnetic moment of the vertical component Cβ of the magnetic pole C. It repels and moves to the surface side of the silicon plate 23 (the front side of FIG. 3). Similarly, the portion f in the figure is magnetized to the N pole by the magnetic moment of the vertical component Cβ of the magnetic pole C, so that it repels the magnetic field of the coil 15 and the back side of the silicon plate 23 (on the paper surface of FIG. 3). Move to the back side. Therefore, the pair of torsion springs 40 and 41 in the vertical direction is tilted in the direction of arrow E in the drawing with the vertical center of the mirror portion 37 as the center of rotation.

  FIG. 4 is a diagram showing a scanning locus of the scanner unit mirror. The horizontal direction (left-right direction of the silicon plate 23 shown in FIG. 3) is resonant scanning with a deflection angle of 20 degrees and a frequency of 50 Hz. Further, the vertical direction (the vertical direction of the silicon plate 23 shown in FIG. 3) is resonant scanning with a deflection angle of 5 degrees and a frequency of 250 Hz. Since the horizontal / vertical frequency ratio is 5, a scanning trajectory 51 that alternates once in the horizontal direction is drawn when it alternates five times in the vertical direction. In addition, since the scanning locus | trajectory 51 becomes a standing wave and passes the same place, the irradiation defect part 52 of a laser beam arises.

  FIG. 5 is an enlarged view of a portion F in FIG. In FIG. 4, the scanning trajectory 51 is drawn with a thin line. Actually, however, resonance scanning with a deflection angle of 3 degrees and a frequency of 2 kHz is performed by bending resonance of a pair of torsion springs 40 and 41 in the vertical direction as shown in FIG. .

  According to the first embodiment, in addition to the torsional resonance frequency of the pair of torsion springs 38 and 39 and the torsional resonance frequency of the pair of torsion springs 40 and 41, the coil 15 causes a pair of torsion springs. Since an alternating magnetic field having components of bending resonance frequencies of 40 and 41 is generated, horizontal scanning is performed even if the ratio of the natural resonance frequency of the horizontal (left / right) scanning axis to the vertical (up / down) scanning axis is an integer ratio. Or, in addition to the vertical scanning, a new scanning can be added, and the irradiation defect portion 52 (see FIG. 4) where the laser beam irradiation becomes impossible does not occur and is not detected when applied to a laser radar. Since there is no area, the performance of the laser radar can be improved.

In the first embodiment described above, the magnetic thin film formed on the back surface of the silicon plate 23 has the magnetic pole direction of a pair of torsion springs 38 and 39 in the left-right direction and a pair of torsion springs 40 and 41 in the up-down direction. Although an example in which the inclination is 45 degrees from the direction is shown, the inclination in the magnetic pole direction is not limited to 45 degrees, and may be arbitrarily determined according to the necessary degree of force in the left-right direction and the up-down direction. For example, when the horizontal deflection angle is 20 degrees and the vertical deflection angle is 5 degrees, that is, when a force four times as large as the vertical direction is required, tan ⁻¹ (0.25) = 14 degrees is desirable. Also, when the resonance frequency in the left-right direction and the up-down direction are greatly different, or when the shape of the mirror part 37 is greatly different from the square, the optimum inclination angle of the magnetic pole can be determined from the required force obtained by simple geometric calculation. Good. In general, the optimum inclination angle is often in the range of 20 degrees to 70 degrees.

  In the first embodiment, in addition to the torsional resonance between the pair of torsion springs 38 and 39 in the left and right direction and the pair of torsion springs 40 and 41 in the up and down direction, bending of the pair of torsion springs 40 and 41 in the up and down direction is performed. Although an example using resonance is shown, three resonances are not necessarily required. For example, if there is an application in which occurrence of a scanning defect portion does not become a problem, it is not necessary to use bending resonance for the pair of torsion springs 40 and 41 in the vertical direction. In addition to the torsional resonance between the pair of torsion springs 38 and 39 in the left and right direction and the pair of torsion springs 40 and 41 in the up and down direction, bending resonance of the pair of torsion springs 38 and 39 in the left and right direction may be used.

  As described above, according to the first embodiment described above, the pair of the frame 34 provided inside the frame of the support plate 31 and having the magnet surface formed on the back surface and the both ends of the frame 34 supported by the support plate 31. A torsion springs 38 and 39, a mirror portion 37 provided on the inner side of the frame 34, having a mirror surface on the front surface and a magnet surface on the back surface, and a direction orthogonal to the arrangement direction of the pair of torsion springs 38 and 39 And a pair of torsion springs 40 and 41 that support both ends of the mirror portion 37 on the frame 34, and a coil 15 that generates a magnetic field perpendicular to the magnet surface formed on the back surface of the frame 34 and the mirror portion 37. The magnets on the back surface of the frame 34 and the mirror portion 37 are inclined with respect to the direction in which the pair of torsion springs 38 and 39 are aligned and the direction in which the pair of torsion springs 40 and 41 are aligned. Since the pair of torsion springs 38 and 39 and the pair of torsion springs 40 and 41 are used as torsion axes, the mirror portion 37 is tilted in a two-dimensional direction by the magnetic field of the coil 15. A small and inexpensive two-dimensional optical scanner can be provided that can scan in a two-dimensional direction with a small amount of energy.

<< Second Embodiment of the Invention >>
A second embodiment in which the magnetic thin film is not formed only in the portions of the torsion springs 38 to 41 will be described. FIG. 6 is a view of the silicon plate 23 according to the second embodiment as viewed from the back side. In addition, the same code | symbol is attached | subjected to the member similar to the member shown in FIG. 3, and it demonstrates centering on difference. The configuration other than the formation of the magnetic thin film on the back surface of the silicon plate is the same as that of the first embodiment described above, and illustration and description thereof are omitted.

  After slitting the silicon plate 23, when a magnetic thin film is attached to the entire back surface by a technique such as sputtering, a mask 53 is attached to the torsion springs 38 to 41, and only the torsion springs 38 to 41 are magnetic. Avoid forming a thin film.

  Since the magnetic thin film is not attached to the portions of the torsion springs 38 to 41, the magnetostrictive effect of the magnetic thin film does not occur. In particular, the torsion springs 38 to 41 are generally processed to be thin and thin to reduce torsional elasticity in order to increase the deflection angle. Therefore, when a magnetostriction effect due to the magnetic thin film is generated in the portions of the torsion springs 38 to 41, unnecessary stress acts on the torsion springs 38 to 41, thereby preventing resonance of the torsion springs 38 to 41. According to the second embodiment, no magnetostrictive force is generated in the torsion springs 38 to 41 so as to prevent torsional resonance and bending resonance.

  Thus, according to the second embodiment, the support plate 31, the frame 34, the mirror unit 37, the pair of torsion springs 38 and 39, and the pair of torsion springs 40 and 41 are formed from a single silicon thin plate. A processed integrally molded member is formed, and a magnetic thin film is formed on the back surface of the integrally molded member by masking a portion of the pair of torsion springs 38 and 39 and the pair of torsion springs 40 and 41, and the pair of torsion springs 38 , 39 and the alignment direction of the pair of torsion springs 40, 41 are magnetized in a direction inclined, so that in addition to the above-described effects of the first embodiment, A magnetostrictive force that prevents torsional resonance and bending resonance is not generated in the portion, and accurate scanning in a two-dimensional direction is possible.

<< Third Embodiment of the Invention >>
A magnetic thin film is also formed on the portions of the torsion springs 38 to 41. However, only the portion of the torsion springs 38 to 41 is magnetized in a direction in which no magnetostrictive force that prevents torsional resonance and bending resonance is generated. An embodiment will be described. FIG. 7 is a view of the silicon plate 23 of the third embodiment viewed from the back side. In addition, the same code | symbol is attached | subjected to the member similar to the member shown in FIG. 3, and it demonstrates centering on difference. The configuration other than the formation of the magnetic thin film on the back surface of the silicon plate is the same as that of the first embodiment described above, and illustration and description thereof are omitted.

  After slitting the silicon plate 23, a magnetic thin film is attached to the entire back surface by a technique such as sputtering. At this time, a magnetic field in the C direction is formed on the back surface of the silicon plate 23 by performing the sputtering process while applying a strong magnetic field in the direction of the arrow C shown in the drawing. Next, by applying a strong magnetic field perpendicularly to the silicon plate 23 only to the portions 54 to 57 in the vicinity of the torsion springs 38 to 41, the magnetic thin film of the torsion spring portions 54 to 57 is made to have a magnetic pole perpendicular to the silicon plate 23. Magnetize in the direction. At this time, in all the torsion springs 38 to 41, the magnetic poles are aligned so that the back side of the silicon plate becomes the N pole.

  As a result, the magnetic thin film magnetic poles of the torsion spring portions 54 to 57 are the same as the magnetic poles of the coil 15, and the stress due to the magnetostrictive effect acts in a direction perpendicular to the silicon plate 23, but this stress tilts the frame 34 and the mirror portion 37. It will not be a force to let you. As described above, the torsion springs 38 to 41 are generally processed to be thin and thin to reduce the torsional elasticity in order to increase the deflection angle. Therefore, when a magnetostriction effect due to the magnetic thin film is generated in the torsion spring portions 54 to 57, unnecessary stress acts on the torsion springs 38 to 41, thereby preventing the torsion springs 38 to 41 from resonating. According to the third embodiment, no magnetostrictive force that prevents torsional resonance and bending resonance is generated in the torsion spring portions 54 to 57.

  Thus, according to the third embodiment, the support plate 31, the frame 34, the mirror portion 37, the pair of torsion springs 38 and 39, and the pair of torsion springs 40 and 41 are formed from a single silicon thin plate. A processed integrally molded member is formed, and a magnetic thin film is formed on the back surface of the integrally molded member, and only a pair of torsion springs 38 and 39 and a pair of torsion springs 40 and 41 are attached in a direction perpendicular to the integrally molded member. In addition to magnetizing, except for the portions of the pair of torsion springs 38 and 39 and the pair of torsion springs 40 and 41, the arrangement direction of the pair of torsion springs 38 and 39 and the arrangement direction of the pair of torsion springs 40 and 41 In addition to the above-described effects of the first embodiment, the torsion springs 38 to 41 prevent torsional resonance and bending resonance. Not magnetostrictive force is not occur as, on the accurate scanning of the two-dimensional direction is possible, such as a mask member Hakare be simplified process to become unnecessary, the cost can be reduced.

  The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the support plate 31 is a support frame, the frame 34 is an inner frame, the mirror portion 37 is a mirror plate, a pair of torsion springs 38 and 39 in the left and right direction is a pair of torsion springs X1 and X2, and a pair of up and down directions. The torsion springs 40 and 41 constitute a pair of torsion springs Y1 and Y2, and the coil 15 constitutes a magnetic field generating means. In addition, unless the characteristic function of this invention is impaired, each component is not limited to the said structure.

  In the above-described embodiment, an example in which the two-dimensional optical scanner of the present invention is applied to a vehicle laser radar apparatus has been described. However, the two-dimensional optical scanner of the present invention is not limited to a vehicle laser radar apparatus, and a laser It can be applied to any device that emits light and radio waves in a two-dimensional direction.

It is a figure which shows the structure of 1st Embodiment. It is sectional drawing which shows the shape of the scanner part of 1st Embodiment. It is a top view which shows the structure of the silicon plate of 1st Embodiment. It is a figure which shows the scanning locus | trajectory of a scanner part. It is the elements on larger scale of the scanning locus | trajectory of a scanner part. It is a reverse view of the silicon plate of 2nd Embodiment. It is a reverse view of the silicon plate of 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser diode 2 Laser diode drive circuit 3 Control circuit 4 Scanner part 5 Reflector 6 Photo detector 8 Light receiving circuit 9-11, 16-18 Amplifier circuit 12-14 Drive circuit 15 Coil 15a, 15b Power supply terminal 21 Base plate 22 Spacer 23 Silicon Plate 31 Support plate 32, 33, 35, 36 Slit 34 Frame 37 Mirror portions 38, 39, 40, 41 Torsion springs 42, 43, 44 Angle detector 45 Contact pad 51 Scanning locus 52 Laser light irradiation defect portion 53 Mask 54 ~ 57 Torsion spring

Claims (4)

An inner frame provided inside the support frame and having a magnet surface formed on the back surface;
A pair of torsion springs X1, X2 for supporting both ends of the inner frame on the support frame;
A mirror plate provided inside the inner frame, forming a mirror surface on the front surface and forming a magnet surface on the back surface;
A pair of torsion springs Y1, Y2 disposed in a direction perpendicular to the direction in which the pair of torsion springs X1, X2 are arranged, and supporting both ends of the mirror plate on the inner frame;
Magnetic field generating means for generating a magnetic field orthogonal to the magnet surface formed on the inner frame and the back surface of the mirror plate,
Magnetizing the inner frame and the magnet on the back surface of the mirror plate in a direction inclined from the arrangement direction of the pair of torsion springs X1 and X2 and the arrangement direction of the pair of torsion springs Y1 and Y2,
A two-dimensional scanner characterized in that the mirror plate is tilted in a two-dimensional direction by a magnetic field of the magnetic field generating means with the pair of torsion springs X1, X2 and the pair of torsion springs Y1, Y2 as torsion axes. . The two-dimensional scanner according to claim 1.
The support frame, the inner frame, the mirror plate, the pair of torsion springs X1 and X2 and the pair of torsion springs Y1 and Y2 are integrally molded members processed from a single silicon thin plate,
A magnetic thin film is formed on the back surface of the integrally molded member by masking the portions of the pair of torsion springs X1 and X2 and the pair of torsion springs Y1 and Y2, and the pair of torsion springs X1 and X2 are arranged. A two-dimensional scanner characterized by magnetizing in a direction inclined from a direction and an arrangement direction of the pair of torsion springs Y1, Y2. The two-dimensional scanner according to claim 1.
The support frame, the inner frame, the mirror plate, the pair of torsion springs X1 and X2 and the pair of torsion springs Y1 and Y2 are integrally molded members processed from a single silicon thin plate,
A magnetic thin film is formed on the back surface of the integrally molded member, and only the portions of the pair of torsion springs X1 and X2 and the pair of torsion springs Y1 and Y2 are magnetized in a direction perpendicular to the integrally molded member, Except for the portions of the pair of torsion springs X1 and X2 and the pair of torsion springs Y1 and Y2, the alignment direction of the pair of torsion springs X1 and X2 and the alignment direction of the pair of torsion springs Y1 and Y2 A two-dimensional scanner characterized in that it is magnetized in a direction inclined from the side. The two-dimensional scanner according to any one of claims 1 to 3,
In addition to the torsional resonance frequency of the pair of torsion springs X1 and X2 and the torsional resonance frequency of the pair of torsion springs Y1 and Y2, the magnetic field generation means includes bending resonance of the pair of torsion springs X1 and X2. A two-dimensional scanner that generates an alternating magnetic field having a frequency or a component of a bending resonance frequency of the pair of torsion springs Y1 and Y2.

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