Iris controller of television camera

Abstract

Abstract PURPOSE: To make it possible to prevent effectively the deterioration and damage of a pickup tube by stopping down an iris mechanism by supplying power to a lens unit not through a power switch while applying a control voltage to a control terminal. CONSTITUTION: Camera unit 20 is applied with a direct-current voltage through power switch 23 and lens unit 21 with the direct-current voltage by way of switch 23 and relay switch 24. With switch 23 OFF, the supply of power to unit 21 through switch 23 is cut off, but capacitor 26 is discharge through resistance 27 to turn transistor 28 ON, thereby feeding power to unit 21 through switch 24. Further, a control voltage is applied to iris controller 7 to stop down the iris mechanism. Consequently, the deterioration and damage of a pickup tube can effectively be prevented. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Sadami Nakajima

Bibliographic Details