| 摘要 |
PURPOSE:To prevent torsion of an element and a scanning error, by driving a wire on both sides of an optical element, in a scanning optical system of wire- driving. CONSTITUTION:The first optical system 41 and the second optical system 50 run at a speed ratio of 2:1, and scan an original. By a common pulley 60, the first wire 73b and the second wire 73a are driven. One end of both the wires is fixed, and is bridged to fixed pulleys 61, 62 and 63. The first optical system 41 fixed to the first wire 73b moves at the same speed as the wire. The second optical system 50 fixed to a moving pulley 54 to which the second wire 73a has been bridged moves at a half speed of a speed of the wire. Both the optical systems are driven by both its ends, no torsion is generated. |
