AUTOMATIC FOCUSING DEVICE

摘要

PURPOSE:To perform stably such automatic focusing that the amplitude of high frequency components of an image pickup signal is maximum even in case of the illumination of a discharging lamp by providing a reference frequency component detecting circuit to suppress or eliminate unnecessary components. CONSTITUTION:Unnecessary components of frequency components other than reference frequency components of high frequency components of the output signal of an image pickup element 2 are suppressed or eliminated by a reference frequency component detecting circuit 15 such as a BPF or the like. Consequently, reference frequency components where the quantity of unnecessary components due to flicker or the like is small and S/N is good are obtained even in case of the illumination of the discharging lamp, and the position of a lens 1 is controlled by a motor 14 so that the amplitude of these components is maximum, and thus, automatic focusing is performed stably even in case of the illumination of the discharging lamp.