Theta Modulation in Optics

The experiments reported in this paper are similar to the famous Abbe experiments. However, they were done for quite different reasons, namely, to perform certain information processing operations by optical means. Our technique, called theta modulation, allows production of a color image from a black and white film, on which the color object is recorded in encoded form. Furthermore, nonlinear characteristics (H & D curves) of any shape can be realized. A special application of theta modulation, called multiplex storage, will be described. By this technique, more than one image can be recorded in the same area on a piece of film. Subsequently, the individual images can be recovered with a minimum of crosstalk.