| 摘要 |
PURPOSE:To exactly adjust exposure of a small-sized copying machine which has prevented a temperature rise of an optical system, by focusing the exposure light by a fluorescent lamp whose lighting current is controlled in accordance with a DC voltage which is freely adjustable manually through an image focusing optical conductor array. CONSTITUTION:An original irradiation light beam of fluorescent lamps 2, 3 whose temperature rise is a little forms an image on a photosensitive body 8 through an image focusing optical conductor body array which is sensitive to infuence of a temperature, and a copying machine is constituted in small size by a simple optical system. Illumination power of the lamp 2, etc. is detected by a photodiode 9, and it is compared with the set DC voltage VREF in an operational amplifier 12 of a controlling circuit 10, and a current supplied to the lamps 2, 3 is controlled through a dimming stabilizer 20, and the extent of exposure is controlled. This voltage VREF is freely adjusted manually in accordance with time aging, etc. Accordingly, the exposure of a copying machine constituted in small size is adjusted exactly. |
