TV camera with stray light compensating circuit - has integrator with output connected to latching circuit via non-linear resistor

摘要

The TV camera is fitted with a stray light compensation circuit. The circuit will determine the black level. The video signal which is affected by the stray lighting is fed to the input of this latching circuit. The latching circuit is followed by an integrator whose output can be connected to the video signal. The output of the integrator (17, 18, 19) is connected to the input of the latching circuit for determining the black level via a non-linear resistance (22-25) in the stray light compression circuit. The compensation voltage of the latching circuit is a non-linear function of the mean voltage of the video signal.