| 摘要 |
PURPOSE:To generate a good-gradation film independent of the type of an original, by receiving the reflected light in an external section adjacent to the outside circumferential edge of the original and controlling the brightness of an illumination lamp automatically in response to this reflected light. CONSTITUTION:When an original 7 is placed on a platen 3 and a device is operated by a control panel, the light projected from an original illuminating part is reflected from the original 7 and passes through a lens 2, and the image of the original is formed and exposed onto a film 12 in a camera 1. Before this control, the reflected light in the section outside the outside circumferential edge of the original passes through the lens 2 and is reflected by a mirror 11 and is incident to photoelectric elements 13-16, and these element 13-16 are changed by this incidence to determine set levels of automatic dimming circuits 21-24, and the brightness of illumination lamps 25-28 is changed individually to make the illuminance of the irradiated surface of the original 7 uniform. Consequently, a brightness obtained by adding the brightness of an external light and that of dimmed illumination lamps 25-28 is given finally to the section of the platen 3, to which the external light is incident, to make the illuminance of the surface of the original 7 equal to that of other parts. |
