发明授权
US4969005A Backlighting detecting device 失效
背光检测装置

Backlighting detecting device
摘要:
A device for detecting a backlighting condition comprising a light meter of which the image receiving surface is divided into a central area, an intermediate area and a marginal area, and a circuit for discriminating between true and false backlighting conditions in such a way that when the luminance of the marginal area is greater than that of the intermediate area by more than a predetermined value and when the luminance of the intermediate area is greater than that of the central area, the backlighting condition in question is taken as a true one.
公开/授权文献
信息查询
0/0