| 摘要 |
PURPOSE:To eliminate great deviation in light quantity adjusted value from a proper value even if original density is irregular by providing a switch which sets an original density level to one of plural previously displayed values and correcting an original density value detected by a photosensor with the set value of the switch. CONSTITUTION:When an original which has high (low) density is used, the switch 20 is set to a contact L (D) and then the quantity of light of a light source lamp 1 is increased (decreased) automatically, so that the original density detection level of a photosensor 7 is corrected eventually. The values of resistances R4-R6 connected to contacts L, N, and D respectively are so set that a limiter voltage VL is increased in the order of the R4-R6. Then, the light quantity control range set of the setting of the automatic exposure correction switch 20 varies a reference value Vref and the limiter value VL corresponding to the set positions L, N, and D. |
