Auto-focus camera of ttl photometric system

Abstract

Abstract PURPOSE:To prevent the influence of camera shake, electric noise, etc. and to photograph continuously while following up the motion of an object, by providing a means which inhibits lens driving for a prescribed time after focus detection due to a distance measuring means. CONSTITUTION:A distance measuring device 2 uses the transmitted light of a photographic lens 1 to perform the distance measuring operation and outputs a front focus signal Pa, a rear focus signal Pb, or a focus signal Pc. Signals Pa and Pb operate the lens 1 through AND gates 7 and 9 so that the lens 1 is in focus by a lens driving device 8. The signal Pc is inputted to an FF10 of a command circuit 3, and the FF10 outputs a lens driving inhibition signal Pg, and a counter 11 counts pulses from a fundamental clock pulse generating circuit 12. The signal Pg is inverted by an inverter 15 to close gates 7 and 8. Thus, the operation of the device 8 is inhibited for a prescribed time after focusing even if signals Pa and Pb are outputted because of the out-of-focus state due to camera shake, electric noise, etc. and further, the object is photographed continuously while following up its motion.

Inventors

• 👤 Akira Ishizaki
• 👤 明 石崎

Bibliographic Details