| 摘要 |
PURPOSE:To obtain highly reliable automatic picture density detection by using an exposure lamp for AC lighting also as a light source for detecting original density and executing bath processing of a system lowering its resolution so that the detection of the original density coincides with the density of the original ground. CONSTITUTION:The 1st mirror unit 6 provided with an exposure lamp 4 and the 1st mirror 5 is arranged on the inside of a copying machine body 1 and the lower part of an original setting board 2 so as to be moved straight in parallel with the setting board 2 in the right and left direction of the drawing to optically scan the whole surface of an original D. The 2nd mirror unit 9 obtained by uniting the 2nd and 3rd mirrors 7, 8 is straight moved in the right and left direction at a half speed of the unit 6 so that a prescribed optical path length can be held. The reflected light from the original D is reflected by the mirrors 5, 7, 8 and made incident upon the slit S through a main lens 10 and a mirror 11. The lamp 4 is also used as a projector and a sensor A is fitted to the side part of the main lens 10. Under said constitution, the original density is detected by using a part of the image forming optical system on the basis of the stand-by scanning of the optical system and a density histogram is formed to obtain proper copies. |
