| 摘要 |
<p>PURPOSE:To simplify circuit constitution used in common by using a D/A conversion part, which is a constituent element of a sequential comparison type A/D converter for converting brightness and an aperture signal before shutter releasing operation, for flash lighting duration control after the releasing operation. CONSTITUTION:Luminance information 13 and aperture information 12 are A/D- converted by the sequential comparison type A/D converter including the D/A conversion part (a) before shutter releasing operation and then stored in registers 20 and 18 respectively. After the releasing operation, film speed information is D/A-converted by the conversion part (a) and reflected light from a subject by the lighting of a flash B is photodetected and integrated at a part 21 to make a comparison 22 between both. Consequently, when the photodetection integral value reaches a level corresponding to the film speed, the light emission stop control circuit 30 operates to stop the lighting of a flash.</p> |
