JPS5638018A - Camera - Google Patents

Abstract

PURPOSE: To make possible automatic exposure by a desired system with a simple and small constitution by performing exposure operations by respective systems of shutter second time and aperture priority by making combined use of an arithmetic circuit which is sequence-controlled via an ROM.

CONSTITUTION: At the shutter second time priority, the signals for deciding the closing of the shutter selection switch SW₆ of an operation decision setting circuit 3 and the opening of an aperture selection switch SW₇ are applied via a gate circuit 4 to a sequence control circuit 5. An ROM5c is then accessed via the sequence controller 5b of the circuit 5, and an aperture value is calculated by a digital arithmetic circuit 8a to which photometric value, preset second time, etc. are applied according to required processing programs. Said value is then stored in the register SSR of a memory device 10. The same holds true of exposure operation based on an aperture priority program system, thus the circuit 8 is used in combination and the automatic exposure controlling may be performed according to desired photographing systems with the simple and small constitution.

COPYRIGHT: (C)1981,JPO&Japio