A METHOD FOR COMPARISON BETWEEN A FIRST OPTICAL SIGNAL AND AT LEAST ONE OTHER SIGNAL

摘要

Method for comparison between a first optical signal ( PHI 1) and at least one other signal. The invention can for instance be used for image recognition. In this application it is a problem to be able to perform parallel processing of the content of an image. This problem among others is solved in connection with the invention by illuminating a MIS-structure (11; Fig. 1) with the first optical signal ( PHI 1), which creates an optically induced change in the surface potential of the MIS-structure and by influencing the surface potential also by said at least one other signal by illuminating the MIS-structure (11; Fig. 1) with a second optical signal ( PHI 2) or by applying the signal in the form of a voltage across the structure or by providing the structure with charge in the insulator or its interfaces or by a combination of these methods and by varying at least one of all signals as a function of time.