Abstract: An apparatus for photo-electric automatic feedback compensation control is used with a charged coupled device (CCD) scanner to efficiently bring the CCD scanner into optimal operating range by controlling the output intensity of a light source based upon output readings from the CCD. A voltage controlled power supply drives a light source to emit light through an optical system to irradiate a CCD scanner. The voltage induced in the CCD scanner is output and manipulated to produce a digital control signal. When the photo-electric conversion rate of the CCD is too high, the light emitting intensity of the light source is reduced based upon the output of the CCD. When the photo-electric conversion rate of the CCD is too low, the output intensity of the light source is increased based upon the output signal of the CCD scanner.