AUTOMATIC FOCUS MATCHING DEVICE

摘要

PURPOSE:To exactly apply amplitude modulation to a high frequency component of a video signal obtained from a solid-state image pickup element and to improve a focusing accuracy by oscillating the solid-state image pickup element by a reference frequency. CONSTITUTION:A solid-state image pickup element is oscillated by a fine adjustment device connected to the solid-state image pickup element to generate a shading on a photodetective surface of the solid-state image pickup element. Namely, the solid-state image pickup element 22 is oscillated by a reference frequency by the fine adjustment device 33 directly connected to the element and an object picture an image of which is formed on the photodetective surface of the solid-state image pickup element 22 is periodically and optically shaded. Accordingly, a high frequency component included in an output signal of the solid-state image pickup element 22 is modulated in its amplitude. The solid-state image pickup element 22 is smaller and lighter than a lens. Since an inertia of an oscillating system including the fine adjustment device 33 is extremely small, the oscillating system scarcely generates a delay with respect to a reference frequency signal inputted to the fine adjustment device 33 and a stability of a closed loop is improved.