JPS59183339A - Color separator - Google Patents

Abstract

PURPOSE:To perform the color separation of the whole incident rays in real time by a system wherein angles from the normal line of a wavefront of sound waves on a light emission plane of an acoustooptic filter utilizing distant-axis anisotropic Bragg diffraction are made different from an angle on an incident plane and an electric signal of white noise is impressed on the rays. CONSTITUTION:An acoustooptic filter utilizing distant-axis anisotropic Bragg diffraction is employed for an acoustooptic filter 1. Electric signals from a white-noise generator 3 are amplified by an amplifier 4, transduced into an ultrasonic signal by a transducer 2, and propagated through the filter 1. Incident rays lambdai are diffracted and emitted in specified directions in which the frequencies of ultrasonic waves correspond to the wavelengths of the rays in the ratio of 1:1, respectively, and are taken out of an image sensor 5 as electric signals corresponding to the wavelengths of the rays. The angles from the normal line of a wavefront of sound waves on a light emission plane are made different from the angle on an incident plane to magnify the diffusion of the rays. Thereby the rays in the wide range of wavelengths can be diffused simultaneously with high resolution.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a color separation device (monochromator) K used for measuring spectral distribution characteristics of a light source.

Conventional configurations and their problems Conventional monochrome cameras use prisms, diffraction gratings, etc., but because they cannot cover a wide range of light wavelengths, it is difficult to simultaneously measure a wide range of spectra. Ta.

OBJECTS OF THE INVENTION It is an object of the present invention to eliminate such conventional drawbacks and provide a color separation device that can simultaneously perform color separation with high resolution and a wide light wavelength range. In order to achieve the object, the color separation device of the present invention uses an acousto-optic filter (Japanese Unexamined Patent Publication No. 50-23838 ``Acousto-optic Filter'') that utilizes far-axis anisotropic Bragg diffraction, and uses the acoustic wave on the light exit surface of the acousto-optic filter. By making the angle from the wavefront normal direction different from the angle of the incident surface, wavelength dispersion in the light output direction is thickened, and an electric signal from a white noise generator is applied to the acousto-optic filter to generate force and tsuto M
e The configuration is such that the filtered light from the acousto-optic filter is detected by an image sensor.

With this configuration, the incident light is simultaneously diffracted according to the acousto-optic effect by the ultrasonic signal converted from the electric signal of all frequency components within the band of the acousto-optic filter, and is diffracted in the direction corresponding to the wavelength of each light. The light is emitted, but at this time the wavelength dispersion further increases at the exit surface and is shifted by an angle. This separated light is detected by an image sensor placed at an appropriate distance, and the position and light wavelength are read in a form that corresponds to each other. Furthermore, since it is possible to control the intensity of the light that is diffracted by the acousto-optic effect by the intensity of the electrical signal, it is also possible to simultaneously detect and control the intensity of the light based on the signal level from the image sensor. .

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below. The basic configuration of the color separation device is shown in Figure 1, and each condition of the acousto-optic filter is shown in Figure 2.
As shown in the figure. In FIG. 1, 1 is an acousto-optic filter; 2 is an acousto-optic filter;
3 is a white noise generator, 4 is an amplifier, 6 is an image sensor, λ is incident light, and λ is a transducer for converting an electrical signal into an ultrasonic signal. is transmitted light (non-diffracted light), λ1. λ2 indicates the diffracted light, and 6 indicates that the polarization direction of the incident light λ□ is perpendicular to the paper surface.

The electric signal from the white noise generator 3 is amplified by the amplifier 4, becomes an ultrasonic signal by the transducer 2, and propagates through the acousto-optic filter 1. Incident light λ1
The frequency of the il-1 ultrasonic wave and the optical wavelength are diffracted and emitted in specific directions with a one-to-one correspondence, and the image sensor 5
The signal is extracted as an electrical signal from the channel of the image sensor 6 corresponding to the optical wavelength.

In FIG. 2, θi is the light incidence angle with respect to the crystal axis, α is the inclination angle of the ultrasonic wavefront with respect to the crystal axis, β is the angle of the light exit surface with respect to the nine-person incidence plane, and l is the length of the transducer.

For example, tellurium dioxide is used as the medium of an acousto-optic filter, the light incidence angle θ□ is set to 200° from the 11o〉 axis, the ultrasonic inclination angle α is 2° from the 001〉 axis, and the wavelength λ1 is set to 40°.
Ordinary ray component of light from 0 to 700 mm (E vector is the second
When light (perpendicular to the negative surface in the figure) is incident, the frequency is 113 MHz.
A diffracted light is obtained by an electric signal of -51 MHz. At this time, if the length l of the transducer is 15 brains, the optical wavelength resolution will be 1.51 TUn or less. Angle correction β is 5°
Then, the light emission angle is 11.5° to 9.6°. Therefore, by arranging the image sensor on its focal plane using an appropriate lens, a light receiving channel of the image sensor corresponding to the wavelength of light can be obtained.

Effects of the Invention In the color separation device of the present invention, since a white noise generator is used for the electric signal, there is no reduction in resolution due to frequency sweep, and all incident light spectra can be separated in real time. In fact, it is also possible to control the intensity of the light emitted by controlling the level and frequency band characteristics of the amplifier.

As described above, according to the color separation device of the present invention, it is possible to simultaneously separate a wide range of light wavelengths in real time and to control the separation using electrical signals.

[Brief explanation of drawings]

FIG. 1 is a basic configuration diagram showing an embodiment of a color separation device according to the present invention, and FIG. 2 is a basic configuration diagram of an acousto-optic filter constituting the same device. 1... Acousto-optic filter, 3... White noise generator, 5... Image sensor. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure-229-

Claims (1)

[Claims] The angle of the light exit surface of an acousto-optic filter using far-axis anisotropic Bragg diffraction from the normal direction of the wave front of the sound wave is made different from the angle of the entrance surface, and the wavelength dispersion in the light exit direction is increased ((, A color separation device comprising: applying a signal from a white noise generator to the acousto-optic filter; and detecting filtered light from the acousto-optic filter using an image sensor.