| 摘要 |
<p>PURPOSE:To prevent the deterioration of density at the periphery due to a variable magnification lens for obtaining an image without density irregularity in a frame by a method wherein tips having different optical output are selected and arranged. CONSTITUTION:Tips having a higher illuminant output at the same driving current are arranged for illuminant dots at ends of light emitting diode alley C where image illuminance decreases when an image is in focus through a variable magnification lens CL, and the tips having a lower illuminant output are arranged for illuminant dots located on the optical axis of the variable magnification lens in order to constitute a light emitting diode alley light source LEDARY. That is, the tips having a variety of illuminant output are arranged so as to compensate the decrease in the image illuminance according to the central value of the image illuminance distribution range, so that the variation in the image illuminance is diminished as much as possible. Thereby, the decrease in the image illuminance at the periphery of the variable magnification lens is diminished, and the illuminance on the image formation surface of a photo-sensitive plate is made even, so that an image without irregular density within a frame can be obtained.</p> |
