| 摘要 |
PURPOSE:To keep the distribution of intensity of illumination of a projected image uniform on a photosensitive plane by supplementing deficient quantity of light at the part of a platen positioned almost right above a shade. CONSTITUTION:The shade 20 is made of a semitransmissive member of low transmissivity, and has different transmissivity according to positional relation with a flash light source 6. That is, normally distribution of the quantity of light of irradiation is so made that nearly uniform maximum quantity of light is obtained in the part L excepting both end parts of the flash light source 6. The part of the shade 20 positioned right above the part L of the flash light source 6 is formed as a thick part 20a, and at the same time, peripheral part of the thick part 20a of the shade 20 is formed as a thin part that thins out gradually with the distance from the flash light source 6. Average transmissivity of the thick part 20a and thin part 20b is set to, for instance, about 5% and 15%, and made to keep the quantity of transmitted light of the shade 20 going to near right above the shade 20 from the flash light source 6 nearly uniform.
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