path 19 or both photoconductive paths an output will be produced at multi mode optical waveguide 31 this is in contrast to the exclusive or gate operation of fig1 where the input must be exclusively to photoconductive path 18 or photoconductive path 19 in order to produce an output accordingly the concept of the present invention embodies a configuration which will operate in the manner of a nand gate and an or gate in addition to operating as a nor gate an exclusive or gate or an and gate those knowledgeable and skilled in the pertinent prior arts will readily and wholly appreciate that the present invention provides a generalized optical logic element which can simultaneously function to perform different and distinct logic operations this simultaneous operation was not true of known electronic logic elements since each was independently operative consequently if a number of logic operations were required to be performed by means of prior art electronic logic gates the logic operations would have to be done in sequence rather than simultaneously an understanding of the present invention where for instance simultaneous logic operations can be performed providing the functions of a nand gate a nor gate an or gate and an and gate all in the same generalized configuration as shown in fig2 conclusively establishes an outstanding advantage of this innovative concept in both speed and effectiveness of operation moreover the present invention is simple to fabricate and virtually immune.