Light responsive system including load circuit with solid state switch

Claim 1

A LIGHT RESPONSIVE SYSTEM COMPRISING: A PHOTOCELL CIRCUIT INCLUDING A LOAD RESISTOR CONNECTED IN SERIES WITH A SOLAR CELL CHARACTERIZED BY GENERATING CURENT IN RESPONSE A SOLAR CELL CHARACTERIZED BY GENERATING CURENT IN RESPONSE TO LIGHT FALLING THEREON AND EXHIBITING A SUBSTANTIALLY HORIXONTAL FLAT CURRENT CURVE IN THE REVERSE VOLTAGE DIRECTION; SAID LOAD RESISTOR HAVING A VALVE WITH RESPECT TO SAID CELL WHEREBY ITS LOAD LINE INTERSECTS THE USEFUL CHARACTERISTIC CURVES AT SUBSTANTIALLY ZERO VOLTAGE AND BEFORE THE BREAKDOWN VOLTAGE; A LOAD CIRCUIT INCLUDING A LOAD CONNECTED IN SERIES WITH A SEMICONDUCTOR CONTROLLED RECTIFIER HAVING AN ANODE CONNECTED TO THE GATING ELECTRODE; SAID CELL HAVING AN ANODE CONNECTED TO THE GATING ELECTRODE OF SAID RECTIFIER; A SOURCE OF NEGATIVE BIASING VOLTAGE APPLIED TO THE ANODE OF SAID CELL CAUSING SAID SOLAR CELL TO OPERATE ONLY IN THE REVERSE VOLTAGE DIRECTION; AND A SOURCE OF BIAS VOLTAGE APPLIED TO THE RECTIFIER FOR RENDERING SAID RECTIFIER CONDUCTIVE WHEN THE VOLTAGE ACROSS THE CELL IS ZERO.