Focus detector with charge-storing photosensors - gives perfect image signal independently of object brightness variation using adjusting master circuit

摘要

Focus detection system obtains information on object brightness or distance through image signals obtained by photosensors with charge storage or storage and discharge. A control circuit adjusts the charge storage or discharge time of each photosensor so that the light measuring time of each sensor correspons to the object brightness. Pref. the storage or discharge time is varied by varying the interval between the object image scan periods by the photosensors in accordance with object brightness.