| 摘要 |
<p>PURPOSE:To perform complicated correction of optical length with high accuracy, by mechanically separating a driving system of an optical length correcting means from that of a rotating mirror. CONSTITUTION:A main scanning is performed by a one-dimension image sensor 11 and a sub-scanning is performed by a rotating mirror 3. The center of the mirror 3 is provided beneath the left end of the range of the sub-scanning. In this case, the left side of the range of sub-scanning has larger rotating angle of the mirror 3 required for the sub-scanning per unit length than the right side. The number of pulses per unit time applied to a pulse motor with the 1st control circuit 5 depends on known conditions such as the size of a triangle formed with both the ends of the sub-scanning range and the center of the mirror 3 and size of the mirror 3. Thus, the number of pulses to be applied to the motor 4 is calculated and stored in an ROM and the control of the motor 4 can be performed by the storage.</p> |
