| 摘要 |
PURPOSE:To obtain an adequate image meeting each lens magnification and original density by providing a means for controlling variably image forming conditions for developing bias or exposing lamp, etc. according to the change in the lens power. CONSTITUTION:A detecting element 21 which detects the density of a microfilm 2 is disposed in the upper part of a slit means 13 to which an amplifier 22 and a CPU23 are provided and connected. The output signal of the CPU23 is conducted to a voltage source 26 and a bias generating source 27, by which the exposure of a lamp 3 and the developing bias of a developing device 18 are variably controlled according to the density of the film 2. A volume control 28 is provided to the source 27 to permit manual adjustment of the developing bias. Then even if the lens power changes, the adequate image meeting the original density of the original having from low to high density is thus formed. |
