JPH01149019A - acousto-optic element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an acousto-optic device.

BACKGROUND OF THE INVENTION Conventionally, this type of acousto-optic device has had a configuration as shown in FIG. In FIG. 3, 11 is an acousto-optic medium, and one end surface 11a of the medium has an electric signal source (for example, an oscillator).
A transducer 13 connected to 12 is attached, and a sound absorbing material 14 is attached to the other end surface 11b of 1.

In the above configuration, when an electric signal is applied from the electric signal source 12 to the transducer 13, an ultrasonic wave a is generated and travels through the acousto-optic medium 11 toward the sound absorbing material 14. At this time, the incident light beam entering from the light entrance surface 11c of the acousto-optic medium 11 is diffracted by the acousto-optic effect and is emitted as diffracted light C from the light exit surface lid. Note that d is transmitted light.

Problems to be Solved by the Invention With such a conventional configuration, when a device is manufactured using an acousto-optic element, the device becomes long in one direction, and
An external reflecting mirror and a shielding plate to block the undiffracted light are also required, which poses problems such as the inability to downsize the device, high costs, and loss of optical power.

The present invention is intended to solve these problems, and aims to make the device more compact and cost-effective by effectively utilizing space when manufacturing the device, and to reduce the loss of optical power. It is.

Third Means for Solving the Problems In order to solve the above problems, the acousto-optic element of the present invention includes:
In addition to providing an acousto-optic medium with a transducer that generates ultrasonic waves, a reflective film is provided on the surface of the acousto-optic medium opposite to the light incident surface, so that the light reflected by this reflective film is prevented from interacting with the ultrasonic waves again. The surface facing the light entrance surface is inclined with respect to the light entrance surface.

Effect: According to this configuration, the diffracted light and the undiffracted light are reflected by the reflective film on the surface facing the light incident surface, and the undiffracted light is reflected by the reflective film on the incident surface side and does not exit to the incident surface side. Since only the diffracted light is emitted, there is no need for slits or shielding plates to block the non-diffracted light, and even if external reflecting mirrors are used, only a small number are required, so space can be used effectively. At the same time, the device can be made more compact and cost-effective, and loss of optical power can be reduced.

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows a schematic configuration of an acousto-optic element. In FIG. 1, l is an acousto-optic medium, on one end surface 1a of which is attached a transducer 3 that is connected to an electric signal source (for example, an oscillator) 2 to generate ultrasonic waves, and on the other end surface 1b is attached a sound absorbing material 4. is provided. One side surface 1c perpendicular to the one end surface 1a is used as a light incident surface, and a reflective film 5 is provided over the entire other side surface 1d opposite to this light incident surface. , is tilted with respect to the light incident surface so that the diffracted light generated by the acousto-optic effect (interaction by ultrasonic waves) inside the acousto-optic medium 1 is not reflected by the reflective film 5 and subjected to the acousto-optic effect again. ing. Further, a reflective film 6 is partially provided in the center of one side surface 1c, which is the light entrance surface, to reflect only the non-diffracted light out of the t light reflected by the reflection film 5 on the light entrance surface.

Regarding the ff1flF optical element configured as above,
The operation will be explained below.

The incident light A that enters from the light incidence surface is diffracted inside the acousto-optic medium 1 by the acousto-optic effect caused by the ultrasonic waves generated from the transducer 3. The diffracted light B is reflected by the reflective film 5 on the other side surface 1d facing the light incidence surface, but since the other side surface 1d facing the light incidence surface and the light incidence surface are not parallel,
The diffracted light B is again emitted from the light incident surface without being subjected to the acousto-optic effect caused by the ultrasonic waves. On the other hand, the undiffracted light C is reflected by the reflective film 5 on one side 1d facing the light incident surface, and is not subjected to the acousto-optic effect due to the ultrasonic waves again, and is reflected by the reflective film 6 provided on a part of the light incident surface. It is reflected, reflected again by the reflective film 5 on the other side surface 1d facing the light incident surface, and finally scattered, so that only the diffracted light B can be extracted.

By the way, in the above embodiment, the − side surface 1c, that is, the other side surface 1d opposite to the light incident surface, is one surface, but as shown in FIG. A reflective film 5 may be provided on the surface of each of the reflective films 5, and the reflective film 5 may be tilted with respect to the light incident surface so that the fluorescent light reflected by each of the reflective films 5 is not subjected to the acousto-optic effect due to the ultrasonic waves.

Effects of the Invention According to the configuration of the present invention described above, a transducer that generates ultrasonic waves in an acousto-optic medium is installed! In addition, a reflective film is provided on the surface of the acousto-optic medium opposite to the light incidence surface, and the surface facing the light incidence surface is provided with a reflective film so that the light reflected by the reflection film is not subjected to interaction by ultrasonic waves again. Since the plane is tilted with respect to the light incident surface, the diffracted light and undiffracted light are reflected by the reflective film on the surface facing the light incident surface, and the undiffracted light is further reflected by the reflective film on the incident surface side, It does not emit to the side.

In addition, since only the diffracted light is emitted to the incident surface side, there is no need for a t-th slit or shielding plate to block the non-diffracted light, and when incorporating an acousto-optic element into the device, there is less need to use it on the entire exterior of the reflecting bell. Therefore, space can be used effectively, the device itself can be made smaller and less expensive, and optical power loss can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an acousto-optic device according to an embodiment of the present invention, FIG. 2 is a schematic diagram of an acousto-optic device according to another embodiment of the present invention, and FIG. 3 is a diagram of a conventional acousto-optic device. It is a schematic block diagram. 1... Acousto-optic medium, IC...-side (light incident surface)
, 1d...Pond side, 2...Electric signal source, 3...Transducer, 4...Sound absorbing material, 5.6...Reflection film. Agent Yoshihiro Yoshimoto 1st Figure 1 C----1111th page (Yujin Liseki) Itl--1 other 1st rule 3・-Li; Suji user 5.6-It order 2nd Figure 3rd page

Claims (1)

[Claims] 1. A transducer for generating ultrasonic waves is provided in an acousto-optic medium, and a reflective film is provided on the surface of the acousto-optic medium opposite to the light incident surface, so that the light reflected by the reflective film is reflected again. An acousto-optic element in which a surface facing the light entrance surface is inclined with respect to the light entrance surface so as not to receive interaction due to ultrasonic waves. 2. According to claim 1, a reflective film is provided on a part of the light entrance surface to reflect only the undiffracted light out of the diffracted light and the undiffracted light reflected by the reflective film on the light entrance surface again. acousto-optic element. 3. The acousto-optic element according to claim 1, wherein the surface facing the light incident surface provided with the reflective film is multifaceted.