Electrical chopper comprising photo-sensitive transistors and light emissive diode

Claim 1

AN ELECTRO-OPTICAL CHOPPER FOR SWITCHING AN ELECTRICAL SIGNAL FROM A FIRST CIRCUIT TO A SECOND CIRCUIT, COMPRISING: (A) A PAIR OF TRANSISTORS COMPRISED OF A FIRST SEMICONDUCTOR MATERIAL EACH HAVING AN EMITTER REGION, A BASE REGION AND A COLLECTOR REGION WITH THE COLLECTOR REGION OF ONE OF SAID PAIR OF TRANSISTORS INTERCONNECTED WITH THE EMITTER REGION OF THE OTHER OF SAID PAIR OF TRANSISTORS, AND THE COLLECTOR REGION OF SAID OTHER OF SAID PAIR OF TRANSISTORS INTERCONNECTED WITH THE EMITTER REGION OF SAID ONE OF SAID PAIR OF TRANSISTORS TO EFFECT AT LEAST A PARTIAL CANCELLATION OF THE JUNCTION VOLTAGES AS MEASURED BETWEEN THE EMITTER REGIONS OF SAID PAIR OF TRANSISTORS WHEN CONDUCTING, (B) AN INPUT TERMINAL CONNECTED TO THE INTERCONNECTION OF SAID COLLECTOR REGION OF SAID ONE OF SAID PAIR OF TRANSISTORS AND SAID EMITTER REGION OF SAID OTHER OF SAID PAIR OF TRANSISTORS FOR CONNECTION INTO SAID FIRST CIRCUIT AND FOR THE APPLICATION OF SAID ELECTRICAL SIGNAL THERETO, (C) AN OUTPUT TERMINAL CONNECTED TO THE INTERCONNECTION OF SAID COLLECTOR REGION OF SAID OTHER OF SAID PAIR OF TRANSISTORS AND SAID EMITTER REGION OF SAID ONE OF SAID PAIR OF TRANSISTORS FOR CONNECTION INTO SAID SECOND CIRCUIT, (D) SAID PAIR OF TRANSISTORS CONDUCTING IN RESPONSE TO OPTICAL RADIATION INCIDENT THEREON WHICH HAS A PHOTON ENERGY GREATER THAN THE BAND GAP ENERGY OF SAID FIRST SEMICONDUCTOR MATERIAL, AND (E) A SEMICONDUCTOR LIGHT EMITTING DEVICE FOR GENERATING OPTICAL RADIATION HAVING A PHOTON ENERGY GREATER THAN THE BAND GAP ENERGY OF SAID FIRST SEMICONDUCTOR MATERIAL ELECTRICALLY ISOLATED FROM BUT OPTICALLY COUPLED TO SAID PAIR OF TRANSISTORS FOR DIRECTING SAID OPTICAL RADIATION THEREON, (F) SAID LIGHT EMITTING DEVICE HAVING 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 AND GENERATING SAID OPTICAL RADIATION WHEN A CURRENT IS CAUSED TO FLOW THROUGH SAID JUNCTION IN A FORWARD DIRECTION.