JPS55110227A - Photo control device - Google Patents

Abstract

PURPOSE:To achieve the higher efficiency of photo coupling with a simple constitution by exciting ultrasonic waves in the plural optical fibers disposed in proximity and transmitting only the specific light waves determined from the propagation constants of the light waves and ultrasonic waves to the other optical fiber. CONSTITUTION:There is the one in which an ultrasonic wave transducer 4A common to optical fibers 1, 2 are disposed to apply the ultrasonic waves of the same frequency to the both optical fibers simultaneously and the one in which ultrasonic transducers 4B, 4C of separate frequencies are disposed to the both fibers to apply the ultrasonic waves of separate frequencies to the both optical fibers. With the system of applying the ultrasonic waves of the same frequency to the both optical fibers 1, 2 simultaneously, the light waves satisfying the conditions of formula (1) may be coupled between both optical fibers 1, 2. With sytem of applying the ultrasonic waves of mutually different frequencies to the both fibers, the light waves satisfying the conditions of formula (2) may be coupled between the both optical fibers 1, 2. In this way, the efficiency of the photo coupling may be improved with the simple constitution.