DEFT: Direct electronic Fourier transforms of optical images

A family of novel devices for electronic imaging is described and several different realizations age presented. Direct electronic Fourier transform (DEFT) cameras employ coupling between surface strain waves, the image intensity, and electrical charge to produce electronic signals representing the spatial Fourier transform of the image at a single pair of terminals. This signal can be easily processed to accomplish pattern recognition, all-electronic image magnification (zoom) and stabilization, motion detection, and focusing. Reproduction of the image is expected to be accomplished by a light valve employing strain-induced modulation of uniform light. Experimental results for light intensity variation in one dimension are reviewed for a silicon chip bulk acoustic wave camera and for a CdS surface wave camera. Some preliminary results are also reported for a fused quartz elastobirefringent light valve image reconstruction device.