Electro-optical transistor switching device

Claim 1

AN ELECTRO-OPTICAL COUPLING SYSTEM COMPRISING: (A) A TRANSISTOR COMPRISED OF A FIRST SEMICONDUCTOR MATERIAL HAVING A COLLECTOR REGION, A BASE REGION AND AN EMITTER REGION, (B) CONTACTS CONNECTED TO SAID COLLECTOR REGION AND SAID EMITTER REGION, (C) SAID TRANSISTOR BEING CHARACTERIZED BY THE ABSORPTION OF OPTICAL RADIATION INCIDENT THEREON WHICH HAS A PHOTON ENERGY GREATER THAN TE BAND GAP ENERGY OF SAID FIRST SEMICONDUCTOR MATERIAL FOR GENERATING EXCESS MINORITY CARRIES THEREIN AND BEING RESPONSIVE TO SAID EXCESS MINORITY CARRIERS TO ALTER THE CHARACTERISTICS OF THE COLLECTOR-BASE AND BASE-EMITTER JUNCTIONS THEREOF WHEN SAID OPTICAL RADIATION IS ABSORBED WITHIN A MINORITY CARRIER DIFFUSION LENGTH FROM AT LEAST ONE OF SAID COLLECTOR-BASE AND BASE-EMITTER JUNCTIONS, (D) A LIGHT EMITTING SEMICONDUCTOR DEVICE ELECTRICALLY ISOLATED FROM BUT OPTICALLY COUPLED TO SAID TRANSISTOR AND HVING A FIRST REGION OF ONE CONDUCTIVITY TYPE AND A SECOND REGION OF AN OPPOSITE CONDUCTIVITY TYPE CONTIGUOUS TO AND FORMING A RECTIFYING JUNCTION WITH SAID FIRST REGION, SAID FIRST REGIONA ND A PORTION OF SAID SECOND REGION OF SAID LIGHT EMITTING DEVICE ARE COMPRISED OF A SECOND SEMICONDUCTOR MATERIAL HAVING A BAND GAP ENERGY GREATER THAN THAT OF SAID FIRST SEMICONDUCTOR MATERIAL, AND THE REST OF SAID SECOND REGION IS COMPRISED OF A THIRD SEMICONDUCTOR MATERIAL HAVING A BAND GAP ENERGY GREATER THAN THAT OF SAID SECOND SEMICONDUCTOR MATERIAL WITH SAID SECOND REGION BEING DISPOSED BETWEEN SAID FIRST REGION AND SAID TRANSISTOR, (E) SAID LIGHT EMITTING DEVICE BEING CHARACTERIZED BY THE GENERATION OF SAID OPTICAL RADIATION WHEN A FORWARD CURRENT IS CAUSED TO FLOW THROUGH THE RECTIFYING JUNCTION THEREOF, (F) SAID OPTICAL RADIATION GENERATED BY SAID LIGHT EMITTING DEVICE BEING CHARACTERIZED BY A PHOTON ENERGY GREATER THAN THE BAND GAP ENERGY OF SAID FIRST SEMICONDUCTOR MATERIAL IN WHICH AT LEAST A PORTION THEREOF IS ABSORBED IN SAID TRANSISTOR WITHIN A MINORITY CARRIER DIFFUSION LENGTH FROM AT LEAST ONE OF SAID COLLECTOR-BASE AND BASE-EMITTER JUNCTIONS.