Abstract: An automatic focus adjustment apparatus adapted for use with cameras includes an automatic focusing means for shifting an imaging objective for automatic focusing in response to an output signal from a pair of photo-detectors which receives light radiated from a light emitting element and then reflected from a subject to be photographed. The in-focus range in which the pair of photo-detector means is deemed to receive the substantially equal amount of light is enlarged when the amount of light received by the pair of photo-detector means is smaller than a predetermined amount of light.

Abstract: An automatic focus adjustment apparatus adapted for use with cameras includes an automatic focusing means for shifting an imaging objective for automatic focusing in response to an output signal from a pair of photo-detectors which receives light radiated from a light emitting element and then reflected from a subject to be photographed. The light energy from the light emitting element is controlled by a radiance control means in such a manner that it radiates a diminished energy for a period of time and then restores its light energy.