OPTICAL INFORMATION-PROCESSING BY SYNTHESIS OF THE COHERENCE FUNCTION

We propose an optical parallel information processing technique adopting synthesis of the optical coherence function by using direct frequency modulation of a laser diode. The optical coherence function having a delta-function-like shape can be synthesized by modulating the laser frequency with an appropriate waveform. In this optical parallel information processing system, selective extraction of two-dimensional information from a three-dimensional semitransparent object, and other operations between two-dimensional information, can be carried out. This manner has no mechanical moving part, and there is no need for calculation by combining with holographic method. In this paper, the method to synthesize the optical coherence function is studied in detail. The manner to improve the suppression ratio of unnecessary subpeaks in the delta-function-like coherence function is studied both in theory and experiments. Moreover, notch-shaped optical coherence function is also studied. Selective extraction and selective masking of a two-dimensional information from a three-dimensional object was successfully performed in basic experiments.