JP2009210946A - Oscillating body device, light deflection device, and optical instrument using optical deflection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oscillating body device, capable of using various combinations of bending deformation modes of a plurality of bending beams in a beam structure for rockably supporting a movable body for various purposes such as scanning line interval correction or the like. <P>SOLUTION: The oscillating body device includes a movable body 101, a beam structure which supports the movable body to a support frame 105 so as to be rockable around two oscillating axes, and at least one of drive means and detection means. The beam structure includes a torsion-deformable torsion beam 102 and a plurality of bending-deformable bending beams 103. One end of the torsion beam 102 is connected to the movable body, the other end thereof is connected to one end of each bending beam through a connection part 102, and the other end of each bending beam 103 is connected to the support frame 105. The drive means 106 or 113 selects a combination of bending deformation modes of the bending beams according to a drive signal, and selects at least one oscillation axis to cause angular displacement of the movable body around the oscillation axis. The detection means receives an effect according to the combination of bending deformation modes of the bending beams and detects the angular displacement of the movable body around the at least one oscillation axis. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an oscillator device having a movable body supported so as to be swingable, an optical deflection device, and an optical apparatus using the optical deflection device. In particular, the present invention relates to an optical deflection apparatus that has a configuration capable of executing a distortion correction function of a scanning line and can be manufactured by a micromachining technique, and an optical apparatus using the optical deflection apparatus.

The optical deflecting device is used for, for example, an application for deflecting laser light. There is a galvanometer mirror as a scanning mirror for deflecting and scanning a laser beam. The driving principle of the galvanometer mirror is as follows. When a current is passed through a moving coil arranged in a magnetic field, an electromagnetic force is generated in relation to the current and the magnetic flux, and a torque proportional to the current is generated. The movable coil rotates to an angle at which the torque and the spring force are balanced, and the presence or absence or magnitude of the current is detected by swinging the pointer through the movable coil. The galvanometer mirror uses the principle of such a galvanometer, and is configured by providing a reflecting mirror instead of the pointer on an axis that rotates integrally with the movable coil.

However, a galvanomirror requires a mechanically wound drive coil and a large yoke for generating a magnetic field, and there is a limit to downsizing these mechanical elements mainly because of output torque. At the same time, the size of the entire device for light deflection tends to increase due to the space for assembling each component.

As a small-sized optical deflecting device, there is an optical deflecting device manufactured by using a micromachining technique in which a micromachine is integrally formed on a semiconductor substrate by applying a semiconductor manufacturing technique. As such an optical deflecting device, K.E.Petersen et al. Has proposed Torsional-Scanning-Mirror formed of silicon (see Non-Patent Document 1). In this optical deflecting device, as shown in FIG. 14 (a), the mechanically movable portion 3 includes a mirror 3a as an optical deflecting plate and a beam 3b that supports the mirror. A driving voltage is applied between the mirror 3a and the fixed electrode 2 formed on the substrate, and a torsional moment is applied to the beam 3b by the generated electrostatic attraction force to rotate it to change the deflection angle of the mirror 3a. The maximum deflection angle of the mirror 3a is uniquely determined by the gap interval t0 between the mirror 3a and the substrate. The optical deflecting device having such a configuration can be used as an optical scanner device that scans incident light in a one-dimensional manner, for example, in an image forming apparatus as shown in FIG.

Further, an actuator 10 having a structure in which a mirror 16 as shown in FIG. 14B is arranged to be deflectable around two axes is also disclosed (see Patent Document 1). That is, the movable mirrors 12B and 16 are supported by the gimbal 12A with the two torsion bars 13B, the gimbal is supported by the substrate 11 with the two torsion bars 13A, and the swing axes of the movable mirrors 12B and 16 and the gimbal 12A are orthogonal to each other It has the structure to do. The drive coil 15B is formed on the peripheral part of the movable mirror and gimbal with this configuration, and the permanent magnets 4 and 5 are arranged in the diagonal direction of the movable mirror and the gimbal with the movable mirror and the gimbal sandwiched therebetween. Drive the mirror and gimbal. The optical deflecting device having such a configuration can be used as an optical scanner device that scans incident light two-dimensionally in an image display device as shown in FIG. 13, for example.
IBM J.RES.DEVELOP., VOL.24, NO5,9,1980.P631-637 JP-A-8-322227

In an optical device such as an image forming apparatus or an image display apparatus using a uniaxial light deflector or a biaxial light deflector as described above, an image is formed on the scanning trajectory of the laser beam written on the photosensitive member or on the projection surface. The scanning trajectory of the laser beam is generally as shown in FIG. As can be seen from FIG. 11 (a), the interval between the scanning lines turned back near the end of the scanning pattern is narrowed. As a result, the pixel spacing becomes uneven near the end of the scanning pattern, and it is not easy to obtain an image with sufficient resolution. In the case of so-called multi-beam scanning in which light from a plurality of light sources is simultaneously scanned, it is not easy to align the scanning lines and the problem described above is likely to be significant.

The first oscillator device according to the present invention has the following characteristics. That is, the present oscillator device includes a movable body, a beam structure that supports the movable body with respect to the support frame so as to be swingable about two orthogonal swing shafts, and a driving means for driving the movable body. And at least one of detecting means for detecting the movement of the movable body. The beam structure includes at least a torsional beam that can be torsionally deformed and at least a plurality of bending beams that can be bent and deformed. One end of the torsion beam is connected to the movable body, the other end is connected to one end of each bending beam via a connection portion, and the other end of each bending beam is connected to the support frame. The drive means selects a combination of bending deformation modes of the plurality of bending beams according to a drive signal, selects at least one of the two swing shafts, and rotates around the swing shaft. An angular displacement of the movable body is caused. The detection means receives an action corresponding to a combination of bending deformation modes of the plurality of bending beams, and detects an angular displacement of the movable body around at least one of the two swing shafts. To detect.

The second oscillator device according to the present invention has the following characteristics. In other words, the oscillator device includes a movable body and a beam structure that supports the movable body with respect to the support frame so as to be swingable about two orthogonal swing axes. The beam structure includes at least a torsional beam that can be torsionally deformed and at least a plurality of bending beams that can be bent and deformed. One end of the torsion beam is connected to the movable body, the other end is directly connected to one end of each bending beam, and the other end of each bending beam is connected to the support frame.

An optical deflection apparatus according to the present invention includes the oscillator device, wherein the movable body is provided with an optical deflection element, and deflects a light beam incident on the optical deflection element.

An optical apparatus according to the present invention includes the light deflection device, wherein the light deflection device deflects a light beam from a light source and causes at least a part of the light beam to enter a light irradiation object. And

According to the present invention, since the movable body is swingably supported using the beam structure as described above, various combinations of the bending deformation modes of the plurality of bent beams can be used for various applications. Can do. For example, it is possible to flexibly control the angular displacement movement of the movable body or to detect acceleration applied from the outside through the angular displacement of the movable body by the driving means and the detection means as described above. As a typical application, the oscillator device of the present invention can be applied to an optical deflecting device to correct the interval between scanning lines that are folded back at the end of a scanning pattern of deflected light. Thereby, the range of available scanning lines can be widened, and high-resolution image formation is possible.

The basic configuration and principle of the present invention will be described. The first embodiment of the oscillator device according to the present invention basically includes a movable body and a beam structure that supports the movable body with respect to a support frame so as to be swingable around two orthogonal swing axes. Have. Typically, a pair of beam structures is provided with a movable body sandwiched therebetween, but the movable body may be swingably supported by one beam structure in a cantilever manner. The beam structure has one torsional beam that can be torsionally deformed and a plurality of bending beams that can be bent and deformed (typically one pair, but may be a plurality of pairs). One end of the torsion beam is connected to the movable body, the other end is connected to one end of each bending beam via a connection portion, and the other end of each bending beam is connected to the support frame. In such a structure, at least one of driving means for driving the movable body and detection means for detecting the movement of the movable body is provided. The driving means selects an appropriate one according to the application from various combinations of bending deformation modes of the plurality of bending beams according to the driving signal, and at least one of the two oscillating shafts Is selected to cause angular displacement of the movable body around the swing axis. The detecting means detects an angular displacement of the movable body around at least one of the two oscillating shafts by receiving an action corresponding to a combination of bending deformation modes of the plurality of bending beams. Thereby, it can be used as a sensor for detecting acceleration applied from the outside, or the angular displacement movement of the movable body can be adjusted by controlling the drive signal applied to the driving means by feeding back the detection result of the angular displacement of the movable body. It can be used as an oscillator device.

Further, the second embodiment of the oscillator device according to the present invention basically has a beam structure that supports the movable body and the support frame so as to be swingable around two orthogonal swing axes. Have a body. Here, typically, a pair of beam structures is provided with the movable body sandwiched therebetween, but the movable body may be swingably supported by one beam structure in a cantilever manner. The beam structure has one torsional beam that can be torsionally deformed and a plurality of bending beams that can be bent and deformed, and the torsional beam has one end connected to the movable body and the other end directly connected to one end of each bending beam. Connected to The other end of each bending beam is connected to a support frame. Here, each curved beam is typically connected at a right angle to the other end of the torsion beam. Moreover, you may have at least one of the above drive means and a detection means. Similar to the first embodiment, various combinations of bending deformation modes of a plurality of bending beams can be used for various purposes, and the above-described operation can be performed.

When the embodiment having the above basic configuration is applied to an optical deflecting device that scans incident light in one or two dimensions, for example, along with the original optical scanning function, the scanning line near the end of the scanning pattern The function of correcting the interval can be performed.

Hereinafter, the present invention will be described in detail with reference to examples.
(Example 1)
FIG. 1 (a) is a top view showing a configuration of a first embodiment relating to an optical deflection device using the oscillator device of the present invention. FIG. 1B is a cross-sectional view taken along the line AA ′ in FIG. FIG. 1 (c) is a cross-sectional view taken along the line BB ′ of FIG. 1 (a). FIG. 1 (d) is a cross-sectional view taken along the line CC ′ of FIG. 1 (a). FIG. 1 (e) is a cross-sectional view taken along the line DD ′ of FIG. 1 (a). 2 (a) to 2 (c), 3 (a), and 3 (b) are diagrams illustrating a driving method for optical scanning in the Y direction, using the cross-sectional view of FIG. 1 (b). is there. 4 (a) to 4 (c), 5 (a), and 5 (b) are diagrams illustrating a driving method for scanning in the X direction, using the cross-sectional view of FIG. 1 (e). .

In this embodiment, the movable mirror 101, which is provided with a reflecting surface as a light deflecting element on the movable body and deflects the incident light beam, is supported by the beam structure so as to be swingable around two orthogonal swing axes. The frame 105 is supported. The beam structure includes at least a torsion beam 102 that can be torsionally deformed, a plurality (two in this case) of bending beams 103 that can be bent and deformed, and a connecting portion 104. One end of the torsion beam 102 is connected to the movable mirror 101, and the other end is connected to one end of each bending beam 103 via the connection portion 104. The other end of each bending beam 103 is connected to the support frame 105.

In the present embodiment, the two orthogonal swing axes extend in the X direction and the Y direction, respectively. Each connecting portion 104 is connected to the other end of the torsion beam 102 and the one end of each bending beam 103 at substantially right angles, and the torsion beam 102 and each bending beam 103 extend substantially parallel to each other. The two bent beams 103 are arranged symmetrically with a swing shaft extending in the Y direction defined by the extension direction of the torsion beam 102 interposed therebetween. Here, a pair of beam structures are provided across the movable mirror 101, and this form is a preferred form for stable operation, but the movable mirror 101 is a single beam structure in a cantilever manner. The support frame 105 may be swingably supported. The movable mirror 101, the torsion beam 101, the bending beam 103, the connection portion 104, and the support frame 105 can be integrally formed by removing the flat single crystal silicon.

On each bending beam 103, an actuator capable of extending and contracting, which is a driving means for driving the movable mirror 101, is provided. As the actuator that can be expanded and contracted, for example, piezoelectric bodies 106 to 113 that can expand and contract in the length direction of the beam by applying a voltage signal can be used. The piezoelectric bodies 106 to 113 are disposed on the bending beam 103 on which an insulating layer (not shown) is formed. An oxide film can be used for the insulating layer. In addition, wirings are formed in the piezoelectric bodies 106 to 113 so that the movement can be controlled (not shown). The driving means selects a combination of bending deformation modes of the plurality of bending beams 103 according to the driving signal, selects at least one of the two swing shafts, and a movable mirror around the swing shaft Causes 101 angular displacement.

In this embodiment, the piezoelectric bodies 106 to 113 are arranged on the upper and lower surfaces of all the bending beams 103, but any arrangement may be used as long as the arrangement can execute the function of the driving means. May be. For example, the piezoelectric body may be provided only on the upper surface or the lower surface of all the bending beams 103. Further, a piezoelectric body may be provided only on the upper surface of the two right bending beams 103 and the lower surface of the two left bending beams 103 with the movable mirror 101 in FIG. Alternatively, a piezoelectric body may be provided only on the upper surface of the upper two bending beams 103 and the lower surface of the lower two bending beams 103 across the swing shaft extending in the Y direction in FIG. .

A method of driving the optical deflector having the above configuration will be described with reference to FIGS.
When a constant voltage signal is applied only to the piezoelectric bodies 107, 109, 110, and 112, the movable mirror 102 is angularly displaced about the swing axis extending in the X direction as shown in FIG. In addition, when applying a constant voltage signal only to the piezoelectric bodies 106, 108, 111, 113, the movable mirror 102 moves in the X direction in the opposite direction to that in FIG. 2 (a) as shown in FIG. 2 (c). Angular displacement about the extending swing axis. FIG. 2 (b) shows the state of the neutral position taken by the movable mirror 102 when no constant voltage signal is applied to any piezoelectric body. By periodically applying the drive voltage signal of FIG. 3 (a) to the piezoelectric bodies 107, 109, 110, 112 and the drive voltage signal of FIG. 3 (b) to the piezoelectric bodies 106, 108, 111, 113, the movable mirror 102 Repeats the angular displacement motion as shown in Fig. 2 (a)->(b)->(c)->(b)-> (a).

On the other hand, when a constant voltage signal is applied only to the piezoelectric bodies 106, 110, 109, 113, the movable mirror 102 is angularly displaced about the swing axis extending in the Y direction as shown in FIG. In addition, when applying a constant voltage signal only to the piezoelectric bodies 107, 111, 108, 112, the movable mirror 102 moves in the Y direction in the opposite direction to that in FIG. 4 (a) as shown in FIG. 4 (c). Angular displacement about the extending swing axis. FIG. 4B shows a state of the neutral position that the movable mirror 102 takes when no constant voltage signal is applied to any piezoelectric body. By periodically applying the drive voltage signal of FIG. 5A to the piezoelectric bodies 106, 110, 109, and 113 and applying the drive voltage signal of FIG. 5B to the piezoelectric bodies 107, 111, 108, and 112, the movable mirror 102 Repeats the angular displacement motion as shown in Fig. 4 (a)-> (b)-> (c)-> (b)-> (a).

By superimposing the angular displacement motions shown in FIGS. 2 and 4, the movable mirror 102 swings around the two swing axes, and light incident thereon can be deflected in the X direction and the Y direction. In this embodiment, the frequency of the drive voltage signal is set so that the scanning speed in the Y direction at this time is twice the scanning speed in the X direction. That is, the frequency of the drive voltage signal in FIG. 3 is set to twice the frequency of the drive voltage signal in FIG. In this way, the voltage signal causes the first drive voltage signal that causes the angular displacement of the movable body around one of the two swing shafts, and the angle of the movable body around the other swing shaft. And a second drive voltage signal that causes displacement. Of course, the angular displacement motion shown in FIG. 2 and FIG.

Here, with reference to FIG. 12, an embodiment of an image forming apparatus using the light deflection apparatus having the above-described configuration will be described. Reference numeral 601 denotes an optical deflecting device shown in FIG. 1, which is used as an optical scanner device for scanning incident light in this case. Reference numeral 602 denotes a laser light source. Reference numeral 603 denotes a lens or a lens group, reference numeral 604 denotes a writing lens or lens group, and reference numeral 605 denotes a photoconductor that rotates at a constant speed as a light irradiation target. The laser light emitted from the laser light source 602 is subjected to predetermined intensity modulation related to the optical scanning timing, and is deflected and scanned by the optical deflecting device 601. The scanned laser light forms an image on the photosensitive member 605 by the writing lens 604. The photosensitive member 605 is uniformly charged by a charger (not shown), and an electrostatic latent image is formed by scanning light thereon. Further, a toner image is formed on the image portion of the electrostatic latent image by a developing device (not shown), and this is transferred and fixed on a paper (not shown), for example, thereby forming a visible image on the paper.

The optical scanning in the direction (X direction) perpendicular to the rotation direction of the photosensitive member 605 is performed by the angular displacement motion shown in FIG. For example, the frequency of the drive voltage signal for scanning in the X direction can be set to 20 kHz. This drive voltage signal is preferably a voltage signal that causes the movable body and the torsion beam to torsionally resonate. At this time, scanning in the Y direction orthogonal to the X direction is performed by the angular displacement motion shown in FIG. 2, and the frequency of the drive voltage signal is set to 40 kHz, which is twice the drive frequency in the X direction. The amplitude of the drive signal in the Y direction is appropriately set so that the scanning line intervals are equal. That is, the scanning in the Y direction fulfills the function of correcting the scanning line interval at the end of the scanning pattern. The scanning line locus on the photosensitive member when there is no Y-direction scanning is as shown in FIG. 11 (a), whereas the scanning line locus when the correction function is used is as shown in FIG. 11 (b). Become.

In the above configuration, a part of the piezoelectric body of the driving unit for driving the movable body can be used as a detection unit for detecting the movement of the movable body. The detecting means receives an action corresponding to a combination of bending deformation modes of a plurality of bending beams by the piezoelectric body, and an angle of the movable body around at least one of the two swing shafts. It has a function to detect displacement as a voltage signal. In this case, the detection result of the angular displacement of the movable body by the detection means can be used to adjust and control the angular displacement motion of the movable body by controlling the drive signal fed back and applied to the drive means.

Further, in the above configuration, all the piezoelectric bodies can be used as detection means for detecting the movement of the movable body, and the oscillator device can be used as a sensor for detecting the acceleration around the axis applied from the outside. In this case, the second drive means described in Example 3 to be described later is further provided, and the detection result of the angular displacement of the movable body by the detection means is used as the feedback control signal for the second drive means. You can also Alternatively, as shown in FIG. 2, the functions of all the piezoelectric bodies are specialized in the function of angularly displacing the movable mirror 102 about the swing axis in the X direction, and only the function of correcting the scanning line interval at the end of the scanning pattern is achieved. You may do it. Furthermore, the second driving means described in the third embodiment can be provided in place of the driving means.

As described above, in the optical deflecting device of this embodiment having the above-described configuration, it is possible to correct the interval between the scanning lines that are folded back near the end portion of the scanning pattern, and to widen the range of usable scanning lines. In this way, it is possible to form an image having a high resolution. In addition, the light deflection apparatus of this embodiment can be easily reduced in size, and the image forming apparatus using the light deflection apparatus of this embodiment can also be reduced in size.

(Example 2)
[Embodiment 2] A second embodiment relating to an optical deflection apparatus using the oscillator device of the present invention will be described. In this example, an optical deflector was designed and manufactured as shown in FIG. FIG. 6A is a top view showing the configuration of the optical deflecting device of this embodiment, and FIG. 6B is a cross-sectional view taken along the line AA ′ of the optical deflecting device of FIG.

The configuration of the optical deflection apparatus in the present embodiment is obtained by changing the arrangement of the bending beams of the optical deflection apparatus in FIG. 1 so as to be orthogonal to the torsion beams. That is, the present embodiment includes a movable mirror 801 that is a movable body and a beam structure that supports the movable mirror 801 with respect to the support frame 805 so as to be swingable about two orthogonal swing axes. The beam structure includes at least a torsion beam 802 that can be torsionally deformed and a plurality of bending beams 803 that can be at least bent and deformed. One end of the torsion beam 802 is connected to the movable mirror 801, the other end is connected almost directly to one end of each bending beam 803, and the other end of each bending beam 803 is connected to the support frame 805. Here, a fillet is provided between the torsion beam 802 and the bending beam 803 for reinforcement in strength, but this may be omitted. Each bending beam 803 is connected to the other end of the torsion beam 802 at a substantially right angle. This angle can be changed, and the torsion beam 802 and the two bending beams 803 can be connected in a Y shape.

Also in this embodiment, at least one of a driving unit for driving the movable mirror 801 and a detection unit for detecting the movement of the movable mirror 801 can be provided. Also here, piezoelectric bodies 806 to 813 that can expand and contract in the length direction of the bending beam 803 (however, the piezoelectric bodies 811 and 813 are not visible in FIG. 6) can be used. As described in the first embodiment, a piezoelectric body can be used as a driving unit. In this case, the driving means selects a combination of bending deformation modes of the plurality of bending beams 803 according to the driving signal, selects at least one of the two oscillating shafts, and selects the oscillating shaft. Angular displacement of the surrounding movable mirror 801 occurs. When a piezoelectric body is used as the detection means, the detection means receives an action corresponding to a combination of bending deformation modes of the plurality of bending beams 803, and receives at least one of the two swing shafts. The angular displacement of the surrounding movable mirror 801 is detected. Other configurations, driving methods, and changeable modes are the same as those described in the description of the first embodiment.

Even when the light deflecting device of this embodiment is used in the image forming apparatus shown in FIG. 12, it is possible to correct the spacing of the scanning lines that are folded back near the end of the scanning pattern, thereby widening the range of usable scanning lines. it can. In this way, it is possible to form an image having a high resolution. In addition, the light deflection apparatus of this embodiment can be easily reduced in size, and the image forming apparatus using the light deflection apparatus of this embodiment can also be reduced in size.

(Example 3)
[Embodiment 3] A third embodiment relating to an optical deflector using the oscillator device of the present invention will be described. In this example, an optical deflector was designed and manufactured as shown in FIG. FIG. 7 is a top view showing the configuration of the optical deflecting device of the present embodiment, and FIGS. 9 and 10 illustrate the operation of the structure in the cross section taken along the line AA ′ of the optical deflecting device of FIG. FIG.

In the present embodiment, the movable mirror 901 is supported by the support frame 905 so as to be movable around the two swing axes by a beam structure (a first torsion beam 902, a bending beam 903, and a connecting portion 904). . The support frame 905 is supported by the fixed portion 915 so as to be torsionally rotatable by a second torsion beam 914 that is an elastic support portion. The first torsion beam 902 and the second torsion beam 914 are arranged so as to be orthogonal to each other. The movable mirror 901, the torsion beam 901, the bending beam 903, the connection portion 904, the support frame 905, the second torsion beam 914, and the fixing portion 915 can be integrally formed by removing flat single crystal silicon. The second torsion beam 914 that is an elastic support portion can support the support frame 905 with respect to the fixed portion 915 so as to be swingable around another swing shaft different from the two swing shafts. The support frame 905 is movably supported around a swing shaft extending in the X direction. In other words, the other swing shaft coincides with one swing shaft of the two swing shafts.

On the bending beam 903, an actuator capable of extending and contracting, which is a driving means for driving the movable mirror 901, is provided. As the actuator that can extend and contract, for example, piezoelectric bodies 906 to 913 that can extend and contract in the length direction of the beam can be used. The piezoelectric bodies 906 to 913 are disposed on a bending beam 903 on which an insulating layer (not shown) is formed. An oxide film can be used for the insulating layer. In addition, wirings are formed on the piezoelectric bodies 906 to 913 (not shown) so that the movement can be controlled. In addition, these piezoelectric bodies are as described in the first embodiment.

In this embodiment, a coil 916 is formed on the support frame 905 on which an insulating layer (not shown) is formed so as to go around the movable mirror 901 and the beam structure. A permanent magnet 917 is arranged outside the coil 916 that generates a magnetic field by applying a current signal so that different magnetic poles face each other. Permanent magnets 917 are arranged in directions inclined 45 ° from the extending directions of the first and second torsion beams 902 and 914, respectively. The coil 916 and the permanent magnet 917 constitute the second driving means. This second driving means is for driving the support frame 905.

8A to 8C and FIGS. 9A to 9C are diagrams for explaining the driving method of this embodiment. FIG. 9 is a cross-sectional view taken along the line A-A ′ of FIG.

In order to cause the movable mirror 901 to undergo angular displacement movement with respect to the support frame 905, a sine wave first drive current signal (FIG. 8A) is applied to the coil 906. The frequency of the sine wave was set to a torsional resonance frequency of 20 kHz with respect to the support frame 905 of the movable mirror 901 and the first torsion beam 902. As a result, the movable mirror 901 performs an angular displacement motion in which the angular displacement with respect to the support frame 905 is sinusoidal (see FIG. 9A). In addition, a sawtooth-shaped second drive current signal (FIG. 8B) is applied to the coil 906 in order to cause the support frame 905 to undergo angular displacement movement with respect to the fixed portion 915. This driving frequency was set to 60 Hz. At this time, the angular displacement of the support frame 905, which is a cymbal, becomes a sawtooth waveform (see FIG. 9B). When only the second drive current signal is applied to the coil 906, the movable mirror 901 is connected to the support frame 905 by the beam structure including the first torsion beam 902. The torsion beam 914 makes an angular displacement movement with respect to the fixed portion 915. By superimposing the first drive current signal and the second drive current signal (Fig. 8 (c)) and applying them to the coil 906, the movable mirror 901 can be angularly displaced in two dimensions with respect to the fixed portion 915. (See Fig. 9 (c)). The scanning pattern at this time is shown in FIG.

On the other hand, by applying the drive voltage signal of FIG. 3A to the piezoelectric bodies 907, 909, 910, and 912 and the drive voltage signal of FIG. 3B to the piezoelectric bodies 906, 908, 911, and 913, the movable mirror 901 is Repeated angular displacement motion as shown in Fig. 10 (a)-> (b)-> (c)-> (b)-> (a). The frequency of this drive voltage signal was set to 40 kHz (twice the resonance frequency of 20 kHz).

The first drive current signal and the second drive current signal are superimposed and applied to the coil 906, and the drive voltage signal is applied to the plurality of piezoelectric bodies as described above, so that the scan line is folded back near the end of the scan pattern. Can be corrected (see FIG. 11B). The correction principle here is as described in the above embodiment.

With reference to FIG. 13, an embodiment of an image display apparatus using the optical deflection apparatus of the present embodiment will be described. First, the modulation light source 1203 is directly modulated by the modulation signal 1202 output from the light source modulation drive unit 1201. In this embodiment, a red semiconductor laser is used as the direct modulation light source 1203. As the direct modulation light source 1203, red, blue, and green light sources that can be directly modulated may be used by mixing them with a color mixing optical system. The output light 1204 directly modulated from the direct modulation light source 1203 is applied to the reflection surface of the light deflector 1205. Further, the reflected light deflected by the light deflecting device 1205 passes through the correction optical system 1206 and is displayed as an image on the image display body 1207 that is an irradiation object. The correction optical system 1206 is an optical system that corrects image distortion due to resonance scanning.

The optical deflecting device 1205 is the optical deflecting device shown in FIG. 7, and an image can be displayed on the image display body 1207 with high resolution by performing raster scanning of the output light 1204 using the optical deflecting device 1205.

The optical deflecting device of this embodiment can also correct the interval of the scanning lines that are folded back near the end of the scanning pattern, can widen the range of usable scanning lines, and can form an image with high resolution. Is possible. In addition, the optical deflecting device of the present embodiment can also be reduced in size, and an image display device using the optical deflecting device of the present embodiment can be made high definition and downsized.

The second driving means comprising the coil and permanent magnet of this embodiment can also be used in the second embodiment. Also in this embodiment, the means made of the piezoelectric material can be used only as the detecting means.

(A) is a top view showing Example 1 of the optical deflecting device of the present invention, (b) is a cross-sectional view taken along the line AA ′ showing Example 1, and (c) is BB ′ showing Example 1. FIG. 4D is a cross-sectional view taken along the line CC ′ of Example 1, and FIG. 5E is a cross-sectional view taken along the line DD ′ of Example 1. FIG. 3 is a cross-sectional view illustrating driving for scanning in the Y direction according to Embodiment 1. FIG. It is a figure explaining the drive signal for the scanning of a Y direction. FIG. 3 is a cross-sectional view illustrating driving for scanning in the X direction according to the first embodiment. It is a figure explaining the drive signal for the scanning of a X direction. (A) is a top view of the second embodiment of the optical deflecting device of the present invention, and (b) is a cross-sectional view taken along the line A-A ′ showing the second embodiment. FIG. 6 is a top view showing Embodiment 3 of the optical deflecting device of the present invention. FIG. 6 is a diagram for explaining a drive signal of Example 3. FIG. 10 is a diagram for explaining a driving method according to the third embodiment. FIG. 10 is a diagram illustrating driving for scanning line interval correction according to the third embodiment. It is a figure explaining a scanning locus. It is a figure explaining one Embodiment of the image forming apparatus using the optical deflection | deviation apparatus of this invention. It is a figure explaining the other form of the image forming apparatus using the optical deflection | deviation apparatus of this invention. It is a figure explaining a prior art example.

Explanation of symbols

101, 801, 901 Movable body (movable mirror)
102, 802, 902 torsion beam (first torsion beam)
103, 803, 903 Curved beam
104, 904 connection
105, 805, 905 Support frame
106 to 113, 806 to 813, 906 to 913 Driving means (detection means, piezoelectric body)
601, 1205 Optical deflection device
602, 1203 Light source (laser light source, direct modulation light source)
605, 1207 Irradiation target (photoreceptor, image display)
914 Elastic support (second torsion beam)
915 Fixed part
916 Second drive means (coil)
917 Second drive means (permanent magnet)

Claims (10)

A movable body,
A beam structure that supports the movable body with respect to a support frame so as to be swingable around two orthogonal swing axes;
At least one of drive means for driving the movable body and detection means for detecting movement of the movable body;
An oscillator device comprising:
The beam structure has at least a torsional beam that can be torsionally deformed, and at least a plurality of bending beams that can be bent and deformed.
One end of the torsion beam is connected to the movable body, and the other end is connected to one end of each bending beam through a connection portion,
The other end of each bending beam is connected to the support frame,
The drive means selects a combination of bending deformation modes of the plurality of bending beams according to a drive signal, selects at least one of the two swing shafts, and rotates around the swing shaft. An angular displacement of the movable body is caused, and the detection means is subjected to an action according to a combination of bending deformation modes of the plurality of bending beams, and at least one of the two oscillating shafts. An oscillator device characterized by detecting angular displacement of the surrounding movable body. Each connecting portion is connected to the other end of the torsion beam and one end of each bending beam at right angles,
2. The oscillator device according to claim 1, wherein the torsion beam and each bending beam extend in parallel to each other. An oscillator device having a movable body and a beam structure that supports the movable body with respect to a support frame so as to be swingable around two orthogonal swing axes,
The beam structure has at least a torsional beam that can be torsionally deformed, and at least a plurality of bending beams that can be bent and deformed.
The torsion beam has one end connected to the movable body and the other end directly connected to one end of each bending beam,
The other end of each bending beam is connected to the support frame. 4. The oscillator device according to claim 3, wherein each of the bending beams is connected to the other end of the torsion beam at a right angle. Having at least one of drive means for driving the movable body and detection means for detecting movement of the movable body;
The drive means selects a combination of bending deformation modes of the plurality of bending beams according to a drive signal, selects at least one of the two swing shafts, and rotates around the swing shaft. An angular displacement of the movable body is caused, and the detection means is subjected to an action according to a combination of bending deformation modes of the plurality of bending beams, and at least one of the two oscillating shafts. 5. The oscillator device according to claim 3, wherein an angular displacement of the surrounding movable body is detected. 6. The driving device according to claim 1, wherein at least one piezoelectric body that expands and contracts when a voltage signal is applied is provided on each of the bending beams. The oscillator device according to the item. The voltage signal is
A first drive voltage signal for causing an angular displacement of the movable body around one of the two swing shafts;
7. The oscillator device according to claim 6, further comprising a second drive voltage signal that causes an angular displacement of the movable body around the other oscillation shaft of the two oscillation shafts. 2. An elastic support portion that supports the support frame with respect to a fixed portion so as to be swingable around a swing shaft, and a second drive means for driving the support frame. 8. The oscillator device according to any one of 1 to 7. 9. An optical deflection device comprising the oscillator device according to claim 1, wherein the movable body is provided with an optical deflection element, and deflects a light beam incident on the optical deflection element. apparatus. It has an optical deflecting device according to claim 9,
An optical apparatus, wherein the light deflector deflects a light beam from a light source and causes at least a part of the light beam to enter a light irradiation target.

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