ELECTRONIC AUTOMATIC FLICKERING DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent a bidirectional thyristor from being turned off readily even if brightness fluctuates slightly when the bidirectional thyristor is turned on once. SOLUTION: A negative liquid crystal plate LC is provided between connection points of resistors R3, R4 and an output terminal X2 so as to reduce the quantity of light to a solar battery SB. The liquid crystal plate LC has a transmissive window having light reducing property to open and close this transmissive window by utilizing a voltage divided by resistors R3, R4 from power supply E. That is, the liquid crystal plate LC closes its transmissive window so as to reduce the light through it when a TRIAC Q1 is turned on and power is not supplied and opens its transmissive window when the TRIAC Q1 is turned off and power is supplied.