| 摘要 |
<p>PURPOSE:To make resetting for the next time unnecessary, by forming an up- down counter for setting and updating a digital signal corresponding to an exposure value, by a non-volatile counter, and holding a set value even after an electric power source of a camera has been turned off. CONSTITUTION:A clock from a clock input controller 1 is counted by an up- down couter 2', and a digital signal corresponding to an exposure value is set and is updated in order. Subsequently, in accordance with comparison of a photometric value and a set value in a CPU 3, and in accordance with shutter second time and aperture priority, proper exposure by opening, shutter second time, etc. is controlled. This counter 2' is formed by a non-volatile counter which has used a semiconductor made of metallic nitride or oxide, etc., and the set digital signal is held even after an electric power source has been turned off. Accordingly, at the time of photographing of the next time, it is unnecessary to reset a digital value corresponding to the exposure value, and camera information is set easily, quickly and exactly.</p> |
