Image pickup device

Abstract

Abstract PURPOSE:To enable precise and quick exposure control by controlling exposure condition of an image pickup device by using output of the image pickup device or output of a sub-photometric circuit continuous in time sequence. CONSTITUTION:After lapse of sufficient time after a power source switch is turned on, a diaphragm 2 is stabilized at a proper value. Accordingly, the result of photometry by a subphotometric circuit 8 does not deviate largely from proper range and output of a window comparator 9 becomes high level. Under this condition, a diaphragm driving circuit 13 controls the diaphragm 2 at high accuracy and in long time constant basing on luminance information from an image pickup element 5. On the other hand. In the case of sudden change of luminance of the subject, the diaphragm can not follow up quickly. Accordingly, output of the circuit 8 becomes a value largely deviated from the proper range, and output of the comparator 9 becomes low level. Then, the circuit 13 controls the diaphragm 2 in real timing basing on information of the circuit 8.

Inventors

• 👤 Tadashi Okino
• 👤 沖野　正
• 👤 Shinji Sakai
• 👤 堺　信二

Bibliographic Details