Circuit for displaying and controlling the ratios of ambient light

摘要

The circuit has a photoelement (F), detecting the background light level, coupled to an amplifier (V), providing a corresponding signal (II) which is mixed with the video signal (I) during operation of the video telephone or multi- media terminal. The combined signal is fed to the image reproduction system (M1) of the video telephone or multi-media terminal, for ensuring a readily visible image, pref. with a digital or analogue display of the background light level.