| 摘要 |
<p>PURPOSE:To shorten the whole exposing time by controlling the brightness of a light source in an area, where the tilt of the gamma characteristic of a photosensitive recording medium is large, lower than that in the other area. CONSTITUTION:A reflector 2 is arranged above a halogen lamp 3 as a light source for exposure and a condensing lens 4 is arranged below the lamp 3, then a liquid crystal display panel 6 is arranged under the lens 4. In such a case, a liquid crystal display panel control means 23 for controlling the display panel 6 in terms of time division and a light source control means 24 for controlling the brightness of the light source 3 in the area where the tilt of the gamma characteristic of the photosensitive recording medium 7 is large lower than that in the other area are provided. By controlling so that the brightness of the light source may be lowered in the area where the tilt of the gamma characteristic of the photosensitive recording medium is large, an output image which is rich in gradation is obtained, and the whole exposing time is shortened because the brightness of the light source is made high in an area where the tilt of the gamma characteristic is small.</p> |
