| 摘要 |
PURPOSE:To adjust the exposure automatically and properly to information of a device which selects freely a position to be set to a proper density from all of regions of an original preliminarily and detects the density of this position, by incorporating this device in a copying machine. CONSTITUTION:A detector 3 is stored in a density detector storing chamber 11 provided in a part of an operation panel 1a which is formed on one side of an original placing table 2 of a copying machine body 1, and a lamp 4 and a lens 5 are so constituted that the intersection between their optical axes is placed on the surface of the original put on the operation panel 1a. The detector 3 is taken out from the chamber 11 and is inverted and is set onto a selected ground part O1 of the original put on the platen 2, and the original is illuminated by a light source 4, and the reflected light is focused on a photodetector 6 by the lens 5 to read the reflection density. The output signal of the density of the photodetector 6 is sent to a processing system circuit, and the quantity of light of an illumination lamp of an original scanning system or/and a charger, a development bias, a lens aperture, a slit width, etc. are controlled to perform the automatic exposure adjustment. |
