2重超音波を利用して発生させた光ビートの応用
I. 実時間相関器
1973 年 42 巻 8 号 p. 807-811
詳細
1973 年 42 巻 8 号 p. 807-811
An optical heterodyne detection-system, consisting of two closely successive ultrasonic wa-ves and an optical mask with a reference signal, has been studied for the purpose of real-time correlational signal processing. The first order in the double diffraction spectrum of laser light by the ultrasonic waves can provide a signal light wave as well as a reference one for photo-mixing. The signal and reference waves arise from the first and second ultrasonic waves, re-spectively. For a system without the mask two time-varying signals, applied to the ultrasonic waves, can be processed in a form of real-time convolution obtainable from the envelope of a beat signal. When the mask is set in the system and only a time-varying signal is fed to one of the ultrasonic waves, the mask and time signals can be processed in a form of real-time correlation.
