| 摘要 |
<p>PURPOSE:To make an exposure correction unnecessary in case when an optical separator for each photometric system is replaced, by varying a reflection factor of a reflection layer of the optical separator which is used in accordance with a photometric area of each photometric system. CONSTITUTION:A part of an image formatin luminous flux from a focusing plate 301 is separated by an optical separator 302, and is led to a photodetector 310. The optical separator executes an optical separation by providing a reflection layer on the relief of the grid, and an area of the reflection layer is varied in accordance with three systems of center importance average photometry, partial photometry and spot photometry. A reflection factor of an area in each system is set so that the quantity of light which is led to the photodetector becomes constant irrespective of a system. Therefore, when selecting each photometric system by replacing a unit frame 304, an exposure correction becomes unnecessary.</p> |
