ANALYSIS AND DESIGN OF PHOTON-COUPLED LOGIC-CIRCUITS

This paper reviews the noise characteristics in photon-coupled circuit s which may be employed in the design of optoelectronic logic gates fo r use in signal processing and computers. A model-based estimate shows that the photon coupled transistor (a form of regenerative optocouple r having very small transit time) has the ability to operate at very l ow noise figures. Quantum efficiencies less than 0.6 have been demonst rated to be sufficient for implementing cascadable logic circuits such as inverters, NOR gates and RS flip flops.