JPS58189618A - Light deflection device - Google Patents

Abstract

PURPOSE:To control deflection angle exactly at high speed with a simple structure, by fixing one end of a material having piezoelectric effect, installing plural pairs of electrodes on both its sides, controlling a number of the electrodes to which voltage is impressed to change angle of a reflective face. CONSTITUTION:One end 11 of a material 1 having piezoelectric effect, such as quartz crystal or barium titanate, is fixed to a base 2, and the other end 12 is left free. Pairs of electrodes 31, 41,-34, 44 are arranged on both sides of the material 1 at equal intervals, and a reflective film 5 is applied onto the electrodes 41-44. Light b1 made incident perpendicularly on the film 5 is reflected and goes back, but when voltage is impressed to the pairs of the electrodes 31, 41-34, 44 across the material 1, it is bent, and its free end 12 is inclined by angle theta, and the incident light b1 is reflected in the direction b2 inclined by angle theta to the normal of the end 12. It can be directed in the desired direction by selecting pairs of the electrodes to which voltage is impressed and changing angle of theta, thus controlling deflection of angle exactly at high speed with a simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION (8) Technical Field of the Invention The present invention relates to an optical deflection device that is effective in deflecting light in optical information processing devices, measurement devices, control devices, and the like.

(b) Prior art and its problems The deflection of a light beam such as a laser beam is used to input information into an optical information processing device, or to apply the light beam to measurement or control. There is. Examples of such a deflection device include a mechanical type such as a rotating mirror, a type using an electro-optic effect, a type using an acousto-optic effect, and the like. However, the mechanical method involves mechanical movement and has a slow response speed, and the method using the electro-optic effect has an element whose refractive index depends on the wavelength of light, lacks stability, and requires a high applied voltage. Furthermore, in the acousto-optic method, the deflection angle is determined by the blank angle of the light, and it cannot be used in applications where the deflection angle can be freely controlled.

(C1 Purpose of the Invention The present invention solves these problems in conventional optical deflection devices, has fast response and excellent stability (can easily obtain any deflection angle, and has a simple configuration). The purpose is to realize a light deflection device that is flexible.

+d) Structure of the Invention In order to achieve this object, the present invention fixes one end of a material having a piezoelectric effect, and provides pairs of electrodes on both sides of the piezoelectric material in the direction from the fixed end to the free end. By substantially arranging a plurality of electrodes, providing a light reflecting surface such that the angle of the reflecting surface changes depending on the deformation of the piezoelectric effect material, and applying a voltage to at least one set of each of the electrodes. , a configuration is adopted in which the angle of the reflective surface is changed.

te1 Embodiment of the invention Next, an embodiment of the optical deflection device according to the invention will be described based on the drawings. FIG. 1 shows a first embodiment of the optical deflection device, in which (a) is a side view and (b) is a front view.

L is a material having a piezoelectric effect, such as crystal or barium titanate, and one end 11 thereof is fixed to the base 2, and the tip is a free end 12.

Pairs of electrodes 31, 41, 32, 42, . . . , 34, 44 are arranged at equal intervals so as to sandwich the piezoelectric effect material 1 from both sides. That is, between electrodes 31 and 41, between electrodes 32 and 4
A voltage is applied between 2, 33 and 43, and 34 and 44. Each of these electrodes 31, 41, 32, 42,...34
- 44 are arranged in a row from the base end 11 to the free end 12. And one electrode 41.42.43.44
A light reflecting object, for example a reflecting film 5, is arranged and fixed on top.

In the state shown by the solid line in the figure, the piezoelectric effect material 1 is not deformed, and the light b1 that is perpendicularly incident on the reflective film 5 in this state is reflected to the same path and returns to its original state. However, electrodes 31 and 41.
When a voltage is applied to 32, 42, . . . , 34, 44, the piezoelectric effect material 1 is deformed by the piezoelectric effect (more precisely, piezoelectric inverse effect) and curves as shown by the chain line. As a result, the free end 12 of the piezoelectric effect material 1 is tilted by an angle θ. When the piezoelectric effect material 1 is curved in this way, the reflective film 5 is exposed to the incident light b1.
Since the light incident on the reflective film 5 is tilted relative to the mirror 5, the light incident on the reflective film 5 is reflected in a direction different from that in the above case, as shown by the broken line.

The inclination angle θ of the piezoelectric effect material 1 can be freely changed depending on the number of electrodes to which voltage is applied. For example, the proximal end
When a voltage is applied only between one pair of electrodes 31 and 41 on the side, the inclination angle θ is small, and therefore the reflection angle θ is also small. In addition to the first electrode 31, 41 from the base end 11, the second electrode 32, 42 or the third and subsequent electrodes 33, 43, 34
- If a voltage is also applied to 44, the inclination angle θ of the free end 12 will further increase, and the light reflection angle θ will also increase. By increasing the number of electrodes to which voltage is applied in this way, the free end 1
In 2, the slope is accumulated, and all electrodes are 31, 41, 32
When a voltage is applied to 42, . . . , 34 and 44, the inclination angle θ of the free end 12 becomes maximum, and the reflection angle θ at a position near the free end 12 also becomes maximum.

By digitally increasing or decreasing the number of electrodes to which a voltage is applied in this way, it is possible to digitally change the reflection angle θ of the reflected light b2 with respect to the incident light b1. Furthermore, in addition to increasing or decreasing the number of electrodes to which a voltage is applied, by changing the magnitude of the applied voltage in an analog manner, it is also possible to abruptly change the inclination angle θ and cause reflection in any direction. Furthermore, since there is no time delay in the piezoelectric phenomenon, the direction of reflection of the incident light b1 can be changed at high speed, which is effective for deflecting the light beam. It can also be used for light scanning by gradually increasing or decreasing the number of electrodes to which voltage is applied and continuously changing the reflection angle θ.

In the above example, the reflective film 5 is provided on the electrodes, but as shown in FIG. 2(A), the electrodes 31, 41, 32, 42,...
・Direct piezoelectric effect material 1 on the side of rows 34 and 44
(B) The reflective film can also be divided as shown by 5 in the figure. Furthermore, a reflective film may be provided only at a position near the free end 12 of the piezoelectric effect material 1. It is needless to say that the electrodes can be connected in common by making one ground side continuous.

(F1 Effects of the Invention As described above, according to the present invention, one end of a material having a piezoelectric effect is fixed, and electrodes forming a pair with each other are arranged on both sides of the piezoelectric effect material substantially in the direction from the fixed end to the free end. By controlling the number of electrodes to which a voltage is applied, the amount of deformation of the piezoelectric effect material can be changed.The angle of the reflecting surface changes according to the deformation of the piezoelectric effect material. A light reflecting surface is provided as shown in FIG. This allows the light beam to be deflected in the desired direction, and since it utilizes the piezoelectric effect, high-speed operation is possible, the deflection angle can be precisely controlled, and the configuration is extremely simple. An inexpensive and popular optical deflection device can be realized.

[Brief explanation of drawings]

The drawings show embodiments of the present invention; FIG. 1 is a side view and front view of the first embodiment, and FIGS. 2(a) and 2(b) are views showing different embodiments. In the figure, 1 is a piezoelectric effect material, 12 is a free end, 31.
41, 32, 42, . . . 34, 44 are electrodes, and 5 is a reflective film, respectively.

Claims (1)

[Claims] One end of a substance having a piezoelectric effect material is fixed, and a plurality of paired electrodes are substantially arranged on both sides of the piezoelectric effect material in the direction from the fixed end to the free end, and the piezoelectric effect material is deformed. A light reflecting surface configured to change the angle of the reflecting surface by providing a light reflecting surface such that the angle of the reflecting surface changes by applying a voltage to at least one set of each of the electrodes. Deflection device.