JP2002328317A - Light deflector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light deflector capable of obtaining a large deflection angle of a light refection part with a low driving voltage. SOLUTION: The light deflector comprises a fixing base 4 having an opening 4a and equipped with a first supporting part 3a protruding toward the central part of the opening 4a, a supporting base 2 arranged on the opening 4a and equipped with a second supporting part 6a arranged facing the first supporting part 3a radially protruding from the peripheral part, a plurality of elastic members 5 connecting to the supporting base 2 and the fixing base 4, a light reflection part 1 placed on the supporting base 2 so as a reflection part 1a to make a prescribed angle, a first electrode 3 arranged on a first comb-shaped part 3A of the first supporting part 3a, and a second electrode 6 arranged on a second comb-shaped part 6A of the second supporting part 6a. A potential is impressed to between the first electrode 3 and the second electrode to make them attract and repel each other by static electricity and oscillate the supporting base 2, thereby, to make the light incident on the reflection part 1a of the light reflection part 1 reflected at a prescribed angle. Voltage is applied between the first electrode 3 and the second electrode 6. The first supporting part 3a and the second supporting part 6a are sucked and repelled by electrostatic force. The supporting base 2 is swung, and light incident on the reflection part 1a of the light reflection part 1 is reflected by the prescribed angle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical deflector, and more particularly, to an optical scanner used for continuously scanning laser light, and a light for changing the direction by deflecting the laser light to a predetermined angle. The present invention relates to an optical deflector suitable for a switch, an optical cross connect, and the like.

[0002]

2. Description of the Related Art Scanning devices for optical equipment such as electrophotographic copying machines, laser beam printers, bar code readers, etc., optical deflecting devices for optical disk tracking control devices, and display devices for scanning laser beams and projecting images. For example, an optical deflector is used.

[0003] In general, optical deflectors for mechanically deflecting light include a rotary polygon mirror (polygon mirror) and a vibrating reflecting mirror (galvano mirror). The galvanomirror type is a polygon mirror type. The mechanism can be made smaller than that of, and a prototype of a micromirror using a silicon substrate by applying recent semiconductor process technology has been reported. Further reductions in size, weight, and cost can be expected. .

Conventional examples of such a galvanomirror type optical deflector are shown in FIGS. 6 and 7, respectively.

FIG. 6 is an exploded perspective view showing a first conventional optical deflector. In FIG. 6, a base 59 is provided with a pair of left and right support portions 51 and 52, and this pair of support portions 5 is provided.
A vibrating body 53 is arranged on 1 and 52. The vibrating body 53 includes an outer frame 54 and an opening 54 of the outer frame 54.
a, and a pair of beams 56, 56 connecting the reflection mirror 55 and the outer frame 54 at an axial position passing through the center of gravity of the reflection mirror 55. Is formed. The left and right ends of the outer frame 54 are fixed on a pair of support parts 51 and 52.

The driving means D has a pair of left and right fixed electrodes 57 and 58 disposed on a base 59, and the pair of fixed electrodes 57 and 58 are located at positions opposed to both left and right ends of the reflection mirror 55. Are located in This pair of fixed electrodes 5
A reflection mirror section 55 is provided as an electrode on the other side of the pair of fixed electrodes 57 and 58. A voltage is selectively applied between one of the pair of fixed electrodes 57 and 58 and the reflection mirror section 55 via a switch SW. It can be applied. Since the reflection mirror 55 is connected to the outer frame 54 via the pair of beams 56, 56, the voltage applied to the reflection mirror 55 may be applied to the outer frame 54.

[0007] The first conventional optical deflector 50A having the above-described configuration.
In the above, when a voltage is applied between one fixed electrode 57 and the reflection mirror portion 55, the left side of the reflection mirror portion 55 with respect to the drawing is attracted by electrostatic force, and the reflection mirror portion 55 is moved to the pair of beam portions 56. , 56, and when a voltage is applied between the other fixed electrode 58 and the reflection mirror portion 55, the right side of the reflection mirror portion 55 is attracted by electrostatic force and the reflection mirror portion is attracted. The portion 55 rotates clockwise about the pair of beam portions 56, 56. Therefore, the reflection mirror 55 vibrates right and left by alternately applying a voltage to the pair of fixed electrodes 57 and 58 by the driving means D. The reflection angle of the light incident on the reflection mirror section 55 is changed by the vibration of the reflection mirror section 55, and the light is deflected by this.

FIG. 7 is an exploded perspective view showing a second conventional optical deflector. In FIG. 7, the same components as those of the first conventional example in the second conventional example are denoted by the same reference numerals in the drawings, and the description thereof will be omitted. Only different components will be described.

That is, in the optical deflector 50B of the second conventional example, the driving means D is disposed on a pair of left and right permanent magnets 60 and 61 disposed on the base 59 and on the outer peripheral portion of the reflection mirror section 55. And a driving coil 62, and a driving current is supplied to the driving coil 62 alternately in the forward and reverse directions.

In the optical deflector 50B having the above-described configuration, when a driving current is applied to the driving coil 62 by the driving means D in the alternate direction, the external magnetic field of the pair of permanent magnets 60 and 61 and the driving coil 62 The reflection mirror 55 oscillates around the pair of beams 56, 56 by Lorentz force caused by the current.

[0011]

By the way, as in the optical deflector 50A of the first conventional example, in the case of a type in which the reflection mirror portion (light reflection portion) 55 is tilted or vibrated by an electrostatic force (also referred to as an electrostatic structure). In), the reflection mirror 55
In order to increase the deflection angle (also referred to as an optical scanning angle), it is necessary to increase the gap between the fixed electrodes 57 and 58 and the reflection mirror unit 55. However, the electrostatic force
Since it is inversely proportional to the square of the gap interval, there is a problem that it is necessary to apply a large voltage between the fixed electrodes 57 and 58 and the reflection mirror unit 55 to obtain a large deflection angle.

Further, in the case of a type in which the reflection mirror section (light reflection section) 55 is tilted or vibrated by the Lorentz force as in the optical deflector 50B of the second conventional example, the deflection angle of the reflection mirror section 55 is increased. In order to achieve this, it is necessary to obtain a large Lorentz force by increasing the current flowing through the drive coil 62, and the reflection mirror 55 is deformed by the generation of Joule heat due to the flow of the large current, resulting in a large deflection angle. There is a problem that it is difficult to stably obtain.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an optical deflector having a simple structure and capable of obtaining a large deflection angle of a light reflecting portion with a small driving voltage. It is assumed that.

[0014]

As a means for achieving the above object, the optical deflector of the present invention has an opening and a first supporting portion protruding toward the center of the opening. A support base, a support base including a second support portion disposed in the opening and radially protruding from a peripheral edge and opposed to the first support portion; and the support base and the fixed base And a plurality of elastic members for connecting the first and second supporting members, a light reflecting portion having a reflecting portion mounted on the support table at a predetermined angle, and a second reflecting portion disposed on a first comb portion of the first supporting portion. A first electrode, and a second electrode disposed on a second comb-like portion of the second support portion, wherein a voltage is applied between the first electrode and the second electrode, and a voltage is applied between the first electrode and the second electrode. And the second support portion is attracted and repelled by electrostatic force, the support base is swung, and the light incident on the reflection portion of the light reflection portion An optical deflector for causing reflected at a predetermined angle.

[0015]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

<First Embodiment> FIG. 1 is a top view showing a first embodiment of the optical deflector of the present invention. FIG. 2 is a sectional view taken along the line AA 'shown in FIG. FIG. 3 shows a first example of the optical deflector of the present invention.
FIG. 4 is a perspective view illustrating an operation state of the example. The optical deflector 10 according to the first embodiment is provided between the fixed base 4, the support base 2 on which the light reflection unit 1 is disposed, and the fixed base 4 and the support base 2 for holding the support base 2. A plurality of springs 5, a plurality of second electrodes 6 arranged on the support base 2, a plurality of first electrodes 3 arranged on the fixed base 4, and a voltage between the second electrodes 6 and the first electrodes 3. And a driving source (not shown) for applying the voltage.

The light reflecting portion 1 for reflecting the incident light 11 at a predetermined deflection angle is inclined on the support 2 at a predetermined angle (inclination angle) θ with respect to the surface of the support 2. Are located. The end of the light reflecting portion 1 in contact with the support 2 is positioned by a stopper 8, and the height of the light reflecting portion 1 with respect to the support 2 is adjusted by a height adjusting portion 7 that supports a substantially central portion of the light reflecting portion 1. (Tilt angle) is defined. The reflecting portion 1a of the light reflecting portion 1 is mirror-finished, reflects the incident light 11 and emits it as the outgoing light 12.

The support table 2 is, for example, disc-shaped, and
Are arranged in the opening 4a, and a plurality of 2
Although supported by at least one spring 5, it can rotate by a predetermined angle around a rotation center axis 10 c perpendicular to the surface of the support 2. A plurality of, for example, two or more second electrodes 6 are provided on the outer peripheral portion of the support base 2, and the second electrodes 6 are separated from the fixed base 4 by a predetermined distance.

The second electrode 6 is formed on the second support portion 6a and a plurality of comb portions 6A and 6B connected to the second support portion 6a. The second support portion 6a is provided on the outer peripheral portion of the support base 2, and It extends radially toward the fourth side, and one ends of the circumferential comb portions 6A and 6B are connected to these. Combs 6A, 6B
Are arranged at a predetermined distance from the second support portion 6a, for example, at a side in a clockwise direction, and are spaced apart from each other by a predetermined distance.

The fixed base 4 is provided with a plurality of, for example, two or more first electrodes 3 corresponding to the second electrodes 6. First
The electrode 3 is formed on the first support portion 3a and the comb portions 3A and 3B. The first support portion 3a is provided on the inner peripheral portion of the fixed base 4 (on the support base side). They extend radially, and one ends of the circumferential comb portions 3A and 3B are connected to them. The comb portions 3A and 3B are arranged with respect to the first support portion 3a.
The comb portions 6A, 6B and the second support portion 6a are arranged on the opposite side, that is, on the side in the counterclockwise direction in this case, at a predetermined distance from each other.

The comb portions 6A and 6B and the comb portions 3A and 3B3
The comb portion 3A is arranged with a gap provided between the outer peripheral portion of the support base 2 and the comb portion 6A.
A comb portion 3B is arranged with a gap provided between the comb portions 6A and 6B. The ends of the comb portions 6A and 6B opposite to the second support portion 6a and the ends of the comb portions 3A and 3B opposite to the first support portion 3a are arranged to face each other.

The second electrode 6 and the first electrode 3 are insulated from each other, and a drive source (voltage source) (not shown) is connected between the second electrode 6 and the first electrode 3 so that a voltage is applied. When applied, the comb portions 6A, 6B of the comb field electrode 6 and the comb portions 3A, 3B of the first electrode 3 are attracted or repelled to each other by electrostatic force, and the support base 2 is rotated relative to the fixed base 4 with respect to the rotation center. Axis 10
The oscillating rotation is performed at a predetermined angle clockwise or counterclockwise around c. The swing angle at this time is determined by the restoring force acting on the support base 2 counterclockwise or clockwise with respect to the fixed base 4 by the spring 5 and the electrostatic force due to the voltage applied between the second electrode 6 and the first electrode 3. It depends on the balance.

As shown in FIG. 3, the reflecting portion 1 of the light reflecting portion 1
The incident light 11 composed of the laser light incident on the a rotates at the rotation angle determined by the voltage applied between the second electrode 6 and the first electrode 3 together with the swing rotation of the support 2 around the rotation center axis 10c. The light is scanned or deflected by the light reflecting unit 1 and emitted as the emission light 12.

If the optical deflector 10 of the first embodiment is operated so as to stop at a predetermined angle, it can be used for applications such as an optical switch for changing the direction of laser light.
If it operates so as to rotate and reciprocate within a predetermined angle range, it can be used for applications such as an optical scanner.

In the structure of the optical deflector 10 of the first embodiment,
In order to increase the rotation angle around the rotation center axis 10c, the length of the circumferential comb teeth 6A, 6B and the comb teeth 3A, 3B may be increased, and the comb teeth 6A, 6B and the comb teeth 3A, 3B may be increased. Since there is no need to widen the gap between them, there is an advantage that the applied voltage does not need to be extremely increased even if a large rotation angle is required. Further, structurally, since the support base 2 and the fixed base 4 are arranged on the same plane, the micromachine manufacturing technique can be applied to manufacture the semiconductor device by a simple manufacturing process, and the size can be easily reduced.

<Second Embodiment> FIG. 4 is a schematic perspective view showing a second embodiment of the optical deflector of the present invention. The optical deflector 10A according to the second embodiment is the same as the optical deflector 10 according to the first embodiment except that a height adjusting unit 17 is used instead of the height adjusting unit 7. It is configured similarly to.

One end of the height adjusting section 17 has the light reflecting section 1.
Is connected to a slide portion 17A arranged on the support base 2 at the other end thereof so as to be swingable, and has a gear rack and pinion structure capable of reciprocating a predetermined distance in the direction of arrow c. By moving the portion 17A, the inclination angle θ1 of the light reflecting portion 1 with respect to the support 2 of the reflecting portion 1a can be variably set to a value within a predetermined range.

The disc-shaped support base 2 applies a predetermined voltage between the first electrode 3 and the second electrode 6 around its center axis of rotation 10Ac which is at the center of the support base 2 and is perpendicular to the surface. Accordingly, since the light can be rotated at a predetermined rotation angle and the inclination angle θ1 of the light reflecting portion 1 can be changed, the incident light incident on the light reflecting portion 1 can be deflected in two axes.

In the structure of the optical deflector 10A of the second embodiment, in order to increase the rotation angle around the rotation center axis 10Ac, similarly to the first embodiment, the circumferential comb teeth 6A (not shown),
6B and the comb teeth 3A, 3B may be lengthened.
Since there is no need to widen the gap between A, 6B and the comb teeth 3A, 3B, there is an advantage that it is not necessary to extremely increase the applied voltage even if a large rotation angle is required. In addition, this second
The optical deflector 10A of the embodiment can manufacture the gear rack and pinion together with the support base 2, the fixing base 4 and the like by a simple manufacturing process by applying the micromachine manufacturing technology, and can easily downsize the optical switch and the optical switch. It can be applied to optical cross connect.

<Third Embodiment> FIG. 5 is a schematic perspective view showing a third embodiment of the optical deflector of the present invention. The optical deflector 10B according to the third embodiment is different from the optical deflector 10 according to the first embodiment in that the light reflecting portion 1 is provided on the support base 2 which is disposed at a predetermined angle by the stopper 8 and the height adjusting portion 7. Instead, a disc-shaped support base 2B in which the light reflecting unit 1 (not shown) is held and arranged at a predetermined angle by the stopper 8 and the height adjusting unit 7
Is a ring-shaped support base 2A held by a pair of left and right support parts 5A passing through the center of gravity of the support base 2B, and a pair of electrodes 13 respectively disposed at lower portions at both ends separated from the support part 5A of the support base 2B. The configuration is the same as that of the optical deflector 10 of the first embodiment, except that a voltage can be selectively applied between any one of the support 13 and the support 2B.

The support 2A has a second electrode 6 provided on the outer periphery of the support 2A (not shown) around a rotation center axis 10Bc perpendicular to the surface of the support 2 at the center thereof, and a fixed base (not shown). When a predetermined voltage is applied between the first electrode 3 and the first electrode 3 provided on the inner peripheral portion of the motor 4, the motor 4 rotates at a predetermined angle.

The support 2B swings counterclockwise or clockwise around the support 5A by applying a predetermined voltage between one of the electrodes 13 and 13 and the support 2B. Rotate dynamically. Therefore, the incident light can be deflected in two axes by the reflector 1a of the light reflector 1 (not shown).

In the structure of the optical deflector 10B according to the third embodiment, in order to increase the rotation angle around the rotation center axis 10Bc, similarly to the first embodiment, the circumferential comb teeth 6A,
6B and the comb teeth 3A, 3B may be lengthened.
Since there is no need to widen the gap between A, 6B and the comb teeth 3A, 3B, there is an advantage that it is not necessary to extremely increase the applied voltage even if a large rotation angle is required.

The optical deflector 10B according to the third embodiment employs a micromachine fabrication technique to support the support 2A and the support 2A.
B, the supporting portion 5A is processed by etching, patterning, and the like, and the light reflecting portion 1 is die-cut, so that it can be easily manufactured and can be easily miniaturized, and is applied to an optical switch and an optical cross connect. can do.

[0035]

As described above, the optical deflector of the present invention has an opening, a fixed base having a first support protruding toward the center of the opening, and the opening. And a plurality of elastic members for connecting the support table and the fixed table, the support table including a second support section disposed opposite to the first support section and radially protruding from a peripheral edge portion. A light reflecting portion having a reflecting portion mounted on the support table at a predetermined angle; a first electrode disposed on a first comb portion of the first supporting portion; And a second electrode disposed on a second comb-like portion of the first portion.
A voltage is applied between the first support portion and the second electrode.
The support section is attracted and repelled by electrostatic force, the support base is swung, and the light incident on the reflection section of the light reflection section is reflected at a predetermined angle, thereby having a simple structure and a small driving voltage. There is an effect that an optical deflector that can obtain a large deflection angle of the light reflecting portion can be provided.

[Brief description of the drawings]

FIG. 1 is a top view showing a first embodiment of an optical deflector of the present invention.

FIG. 2 is a sectional view taken along the line A-A 'shown in FIG.

FIG. 3 is a perspective view showing an operation state of the first embodiment of the optical deflector of the present invention.

FIG. 4 is a schematic perspective view showing a second embodiment of the optical deflector of the present invention.

FIG. 5 is a schematic perspective view showing a third embodiment of the optical deflector of the present invention.

FIG. 6 is an exploded perspective view showing an optical deflector of a first conventional example.

FIG. 7 is an exploded perspective view showing an optical deflector of a second conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Light reflection part, 1a ... Reflection part, 2, 2A, 2B ... Support base, 3 ... 1st electrode, 3a ... First support part, 3A, 3B ... Comb part, 4 ... Fixed base, 4a ... Opening part, 5 ... Spring, 5A ... support part, 6 ... second electrode, 6a ... second support part, 6A, 6B ... comb part, 7 ... height adjustment part, 8 ... stopper, 10, 10A,
10B: optical deflector, 10c, 10Ac, 10Bc: center axis of rotation, 11: incident light, 12: outgoing light, 13: electrode, 1
Reference numeral 7: height adjustment section, 17A: slide section, 17B: support plate, 50A: optical deflector, 50B: optical deflector, 51: support section, 52: support section, 53: vibrating body, 54: outer frame section, 54
a ... opening, 55 ... reflection mirror, 56 ... beam, 57 ...
Fixed electrode, 58: fixed electrode, 59: base, 60: permanent magnet, 61: permanent magnet, 62: driving coil.

Claims (1)

[Claims] 1. A fixed base having an opening and having a first support protruding toward the center of the opening, and being disposed in the opening and projecting radially from a peripheral edge. A support having a second support disposed opposite to the first support, a plurality of elastic members connecting the support and the fixed base, and a reflecting part having a predetermined angle on the support. A light reflecting portion mounted and mounted; a first electrode disposed on a first comb portion of the first support portion; and a second electrode disposed on a second comb portion of the second support portion. When,
A voltage is applied between the first electrode and the second electrode, the first support and the second support are attracted and repelled by electrostatic force, and the support is oscillated, An optical deflector that reflects light incident on a reflecting portion of the light reflecting portion at a predetermined angle.