Charged voltage display circuit of flash device

Abstract

Abstract PURPOSE:To enable flash photography during flicker display performance of neon tube, by providing a unidirectional conductive element between the neon tube and a trigger controlling capacitor. CONSTITUTION:A diode D1 is connected between a neon tube NL and a trigger controlling capacitor C1 as a unidirectional conductive element. As a result, a main capacitor CM is fully charged, and an oscillating circuit Co is oscillated by the output of a voltage detecting circuit VD to detect the output voltages of voltage dividing resistors R3, R4. Then a transistor T1 becomes ON, and a resistor R2 is short- circuited to put out the neon tube NL. At this time, because of the existence of the diode D1, the charge in the capacitor C1 is held. And when a synchronous switch S1 is turned on by releasing, the charged charge in the capacitor C1 is applied to a thyristor SCR1, and is discharged to a trigger transformer TT, which causes a discharge tube TT to emit a flash. Thus, the intended purpose may be achieved.

Inventors

• 👤 Tadashi Okino

Bibliographic Details