| 摘要 |
<p>In a digital color copying machine that includes means for automatically controlling a light amount of an exposure lamp to be proper, a light amount of a lamp (6) used in the preceding copying is stored in a CPU (118a), and a white reference plate (60) is scanned with the lamp (6) whose light amount is stored. Data read at that time is stored in a RAM (118b) and a maximum average value is calculated by an ALU (118c). A maximum value thus calculated and a reference value of ADC (113) are compared with each other by a comparator (118d). Only when the maximum value is out of a range of reference voltage, a light amount of an illumination lamp (6) is changed by controlling a lamp driver (120). Thus, an optimum light amount of lamp (6) can be set in a short period of time and a standby time for copying can be reduced. <IMAGE></p> |
