OPTICAL MODULATING AND DEFLECTING DEVICE FOR MULTIPLE BEAMS

摘要

PURPOSE:To determine the intensity of an output beam in accordance with the level of input signals by controlling the intensity of an input beam such that the intensity of a non-diffracted light or a reference output beam generated separately takes a preset value. CONSTITUTION:An ultrasonic optical deflecting element 1 is driven in response to the drive signals 2 having a plurality of frequency components f1 to fn so that a plurality of output beams having their intensities modulated and a non-diffracted light 5 are generated by the input beam coming from a light source 20A. The non- diffracted light 5 is received by an optical detector 13 to generated an output proportional to the intensity so that the output is fed to a current output type amplifier 15. A reference voltage is impressed upon one input 16 of the amplifier 15 thereby to constitute a compensating system 12. The intensity of an input beam 3 is so controlled as to make the intensity of the non-diffracted light 5 constant so that the intensity of the output beam 4 can be determined solely in response to its input