| 摘要 |
PURPOSE:To cope with the variation of the density of an originals in case the variation is large by controlling the light emission of an exposure lamp according to the compared result of a 2nd comparison means for comparing the compared result of a 1st comparison means with outputs from a 1st voltage generation means. CONSTITUTION:A voltage corresponding to the impressed voltage of the exposure lamp 6 is generated in the 1st voltage generation means 86. And light from an original is detected and converted into an electrical signal in a conversion means 100. The output from 1 2nd voltage generation means 101 for generating a reference voltage is compared with the output from the conversion means 100. Then the compared result is compared with the output from the 1st voltage generation means 86 so as to control the light emission of the exposure pump 6 according to this compared result. Therefore in the case where the variation of the density of a microfilm which is an original is very large, namely, even if the density of the original is from thin one to thick one or from thick one to thin one, a controller can correspond to it. Thus, a clean print can be obtained. |
