| 摘要 |
<p>PROBLEM TO BE SOLVED: To solve the problem of the conventional illuminance calibration system being applicable to only the case, where the quantity of light of a diaphragm mechanism is linearly related to the amount of operation and an illuminance-switching speed is limited, and of a means for making the illuminance uniform is expensive, complex, and time-consuming. SOLUTION: An illuminance control mechanism comprises a variable diaphragm 7 for changing the illuminance, a plurality of ND filters 8 and 9, a drive means 19 for combining each ND filter, a memory for previously storing the combination of the ND filters for achieving target illuminance value, and a control means for operating a drive means, based on the target illuminance value and for performing control so that the illuminance reaches a target value. Also, an illumination mechanism comprises a uniformizing means 2 for making the illuminance uniform, a mask for limiting the visual field of illumination, and an illumination means for performing telecentric illumination at an exposure position.</p> |
