| 摘要 |
PURPOSE:To simplify the time axis expansion, compression and time delay for an electric signal, by the photoelectric conversion for a light obtained from the modulation to the light with the electric signal given to an acoustooptic processing section. CONSTITUTION:A sinusoidal signal in frequency f1 inputted to a terminal 6 is converted into an ultrasonic signal 11 by an ultrasonic wave oscillator 1 and propagates in a cell toward an ultrasonic wave absorbing member 2. When a plane wave 9 is made incident so as to cross the ultrasonic wave signal, a diffracted light in frequency f1 is obtained. The sinusoidal wave signal in frequency f1 is applied to a terminal 6' through pulse amplitude modulation. A frequency difrracted light corresponding to the sum and the difference of the ultrasonic wave signal 11 and an ultrasonic wave signal from an ultrasonic wave oscillator 1' in the light intensity appears at locations where they are overlapped spatially toward the optical axis. The signal 11 is scanned by another ultrasonic wave signal in accordance with relative speed and its sign of the two ultrasonic wave signals. The change in the amount of output light results in the expansion of the time axis of electric signal. |
