JPS59191019A - Parallel shifting device for light beam - Google Patents

Abstract

PURPOSE:To enable parallel shifting of a light beam with a high response speed and reliability by providing two Peltier effect element pairs facing each other on a pair of parallel side faces. CONSTITUTION:A photoconductor 1, such as TiO2 having a thermooptic effect is of a rectangular prism shape and a light beam 2 propagates therein upward and downward in the Z-axis direction. Peltier effect element pairs 7-10 facing each other are juxtaposed on the opposed side faces 3, 4 in the X-axis direction and similar elements 11-14 are provided on the opposed side faces 5, 6 in the Y-axis direction as well. The element pairs 7-14 heat and cool the contact surfaces in the direction of the current to terminals A1-A4, B1-B4, C1-C4, D1-D4. The beam is shifted parallel by DELTAl in the X-axis direction by driving the elements 7-10. If the elements 11-14 are simultaneously driven, the light beam emitted from the photoconductor 1 is parallel shifted as desired within the X-Y plane.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention provides an opto-electronic device such as a video disk.
The present invention relates to a so-called solid-state parallel shift device for a light beam, which moves the irradiation position of a light beam by a small distance.

(Background of the Invention) As is well known, in opto-electronic equipment, such as video discs, tracking mirrors and optical discs are used. The mirror is slightly rotated by electromagnetic force from an electromagnetic coil, so that a light beam is accurately irradiated onto one track on the disk. As described above, in conventional optoelectronic devices, the irradiation position of the light beam can be avoided by moving the irradiation position by a minute distance in parallel by mechanically rotating or moving optical components such as mirrors.

However, when performing a parallel shift of a light beam using a mechanical IINM, the mechanism becomes complex and requires high precision. Therefore, it is expensive, and miniaturization is an in-house effort.

(Object of the Invention) An object of the present invention is to provide a parallel shift device for a solid-state light beam, which does not require a horizontal mechanical drive, is therefore inexpensive, and can be miniaturized. It's about doing.

(Structure and Effects of the Invention) In order to achieve the above-mentioned [; Effect element pair and second
A pair of Bertier effect elements are arranged side by side, one of the first pair of Bertier effect elements heats the light guide and the other cools the light guide, and the second pair of Bertier effect elements is connected to the first pair of Bertier effect elements. The light beam propagating in the juxtaposed direction of the Vertier effect element pair of 1.12 is
The device is characterized in that the deflected beam is deflected at a predetermined angle (fan surface size V) between the first pair of Peltier effect elements, and the deflected beam is deflected between the second pair of Peltier effect elements in a direction that is a supplementary angle to the predetermined angle. .

According to this configuration, it is possible to provide a so-called solid light beam parallel shift device 1 that can shift a light beam in parallel by a minute distance by utilizing the refractive index change that occurs in the light guide. The refractive index change that occurs inside the light guide is due to the quality optical effect, so
Composition or 1! i) Grade 111 (complicated manufacturing process that causes refractive index changes is not required, therefore extremely -C
It is easy to manufacture and can be made at low cost.

In addition, since the pair of Beltier effect elements is known by electric signals that avoid heating and cooling operations, and the light beam is directly shifted one-dimensionally or two-dimensionally (from 1 to 1), unlike the conventional method, Compared to operating the optical system by a drive mechanism, an excellent effect of increasing the response speed 1σ not only improves reliability but also increases reliability can be obtained. Therefore, an optoelectronic device using the light beam parallel shift device according to the present invention can be made highly reliable, small and lightweight, and can also reduce cost.

(Description of an Embodiment) Fig. 1 does not show an embodiment of the 4'ls shift device for a light beam according to the present invention. It is a light body, for example 110
2, a polymer film, a ferroelectric material such as 1iNb03, or a non-rufus material such as glass. This light guide 1
is formed into a rectangular parallelepiped shape, and the light beam 2 is oriented in the 7-axis direction.
It propagates from the second surface to the bottom surface. Then, a pair of opposite surfaces 3. /I, pairs of Bertier effect elements 7, 8 and 9.10 facing each other are arranged side by side along the propagation direction of the light beam 2, and Bertier effect elements are arranged on a pair of opposing side surfaces 5, 6 formed in the YII11 direction. The pairs 11, 12 and J: and 13, 1=1 are juxtaposed in the propagation direction of the light beam 2.

Each of the above Bertier effect element pairs (7, 8), (9°10>,
(11, 12), (13, 14> are the respective terminals (A
+, B+), (C+, D+).

(A2.B2), (C2, D2>, (A3.B3), (
C3, D3), (A4, B+), (C4, D4)
The respective contacts are heated or cooled in the direction of the drive current supplied to J.

FIG. 2 shows a drive circuit that supplies drive current to each of the terminals. This driving UJ circuit consists of one power supply 21 and two switches 22 and 23 that are connected to both ends of this power supply 21 and are interlocked.
and a current limiting resistor R inserted into the heating drive current path. This resistor R is -6 to limit the heating drive current, thereby making the absolute value of the heating temperature and the cold MI temperature by each pair of Bertier effect elements equal. Note that this drive circuit is for driving the Peltier effect cord pairs 7, 8 and 9, 10 arranged on the opposing side surfaces 3.4 in the The circuits for driving the pair of Bertier effect elements 11.12 and 13.14 arranged in the figure are omitted because they have the same configuration.

This drive circuit drives the pair of Bertier effect elements 7.8 and 9, 10 in the following manner. When the changeover switch 22.23 is operated to the changeover terminal a side, the Peltier effect cable 7 in the pair 7.8 of the Bertier effect element is heated by being supplied with a drive current from the terminal A1 to the terminal 131, and the Bertier effect A driving current is supplied to the element 8 in the direction from the terminal D1 to the terminal C1, and the element 8 performs a cooling operation. And Pelch.”
- In the effect element pair 9.10, the driving current is supplied to the Beltier effect element 9 in the direction from the terminal D2 to the terminal Δ2 and performs a cooling operation, and the driving current is supplied to the Beltier effect element 10 in the direction from the terminal C2 to the terminal D2. heating operation. In other words, the pair of Beltier effect elements is 7.8 and the pair of Beltier effect elements is 9.10.
The operating directions of heating and cooling are opposite to each other. In the illustrated example, the Peltier effect elements 7 and 8
The light beam propagating between them is deflected by a predetermined angle toward the Peltier effect element 7 side, and this deflected beam is propagated between the pair of Peltier effect elements 9 and 10 in a direction that is a supplementary angle to the above predetermined angle, so that the light beam 2 propagates. deflected in a direction approximately parallel to the As a result, the light beam emitted from the light guide 1 is parallel-shifted by Δl in the X-axis direction.

In the above description, each Peltier element pair 7°8 and 9, disposed on a pair of opposing side surfaces formed in the X-axis direction of the light guide 1,
I drove 10, but this! When the pair of Bertier effect elements 11.12 and 13.14 disposed on the axially opposite side surfaces 5 and 6 are also operated simultaneously, the light beam emitted from the light guide 1 can be arbitrarily shifted within the XY plane (this parallel shift is It can be set to 1.

Next, an outline of the parallel shift according to the present invention will be explained with reference to FIGS. 3 and 4. FIG. 3 shows an extracted portion of the pair of Bertier effect elements 7.8, and FIG. 4 shows the temperature distribution and refractive index distribution occurring between the pair of Bertier effect elements 7.8. d5, the light guide 1 is Ti 0
It consists of 2.

In FIG. 4, the reference numeral 41 indicates the temperature distribution generated by the Bertier effect element 7 that performs a heating operation, and the refractive index distribution corresponding to this is the refraction in one direction as a whole, as indicated by the reference numeral 42. The refractive index change is maximum at J5 on the side surface 4 side. What is shown by reference numeral 43-e is the temperature distribution generated by the Bertier effect element 8 which performs cold l'1 operation, and the refractive index distribution corresponding to this is shown by reference numeral 44, which shows the overall refractive index in the child direction. The refractive index change (+Δn) is maximum on the side surface 3 side. Therefore, when the heating operation of the Beltier effect element 7 and the cooling operation of the Beltier effect element 8 are performed at the same time, the refractive index distribution generated between the side surfaces 3. .44
The light beam is a composite of the light beams 2 and is tilted at an appropriate angle with respect to the light beam 2. Since the width of change in the refractive index distribution 45 applied to the portion intersecting the light beam 2 can be made almost uniform at each point, the light beam 2 is directed toward the side surface 3 with a uniform deflection angle θ. will be deflected.

And, although not shown, there is Pelchu. Effect completion vs. 9.1
Between 0 and 0, the Beltier effect element 9 performs a cooling operation,
Since the Pelzi 1 effect element 10 performs a heating operation, the refractive index distribution generated therein is a symmetrical inversion of the refractive index distribution 45.

Therefore, between the pair of Beltier effect elements 9 and 10, the deflected beam deflected by a predetermined angle θ between the pair of Beltier effect elements 7 and 8 is at an angle θ with respect to the traveling direction of this deflected beam, and therefore the deflection angle θ is compensated for. deflected in an angular direction. As a result, the light beam emitted from the output end of the light guide 1 is parallel shifted by Δl in the X-axis direction, as shown above.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a light beam parallel shift device according to the present invention, FIG. 2 is a diagram showing a drive circuit of the above embodiment device, and FIG. 3 is a diagram showing the operation of the above embodiment device. Schematic side sectional view showing a part extracted for explanation, No. 11
The figure is a schematic diagram showing a temperature distribution and a corresponding refractive index distribution between a pair of Peltier effect elements, as well as explaining the deflection effect of a light beam. 1...Light guide 2...Light beam 3.4 and 5, 6...Pair of flat side surfaces 7
．． 8 and 9, 10... 1st. 11.1 “Second Belch” Effect Element Pair
2 and 13.14... 1st. Second pair of Bertier effect elements 41...
...Curve 42 showing temperature distribution due to heating...
・Corresponds to changes in heating temperature (Curve 7'13 corresponds to change in refractive index... Curve 44 corresponds to temperature change due to cold 7i11) <j 2+l Corresponds to changes in quality Curve 45 showing the change in refractive index...The curve θ shows the change in the combined refractive index.
・・・・・・・・・Direction angle Δ℃・・・・・・X 1r111 Direction parallel shift 1 (1 patent applicant Riiko Denki Co., Ltd. Figure 7)

Claims (1)

[Claims] (1) A first pair of Bertier effect elements and a second pair of Bertier effect elements facing each other are arranged side by side on a pair of parallel side surfaces formed on a light guide having a humidity optical effect. One pair of Bertier effect elements heats the light guide and the other cools the light guide, and the second pair of Bertier effect elements heats the light guide in the opposite direction to the first pair of Bertier effect elements. The first one is configured to be cooled while the other is heated;
．． A light beam propagating in the direction in which the second pair of Bertier effect elements are juxtaposed is deflected at a predetermined angle between the first pair of Bertier effect elements, and the deflected beam is deflected at a complementary angle to the predetermined angle between the second pair of Peltier effect elements. What is claimed is: 1. A parallel shift device for a light beam, characterized in that the light beam is deflected in a direction that