| 摘要 |
PURPOSE:To make the device small-sized, by using plural pulse motors to drive an optical system including a reflecting member and driving pulse motors different in driving system simultaneously by a single driving signal. CONSTITUTION:When a signal D for designating the positive direction rotation is applied to excitation phase switching circuits simultaneously (during a time T1), pulse motors 50 and 51 are driven if an excitation phase switching clock C is applied. An excitation phase switching time t2 of the pulse motor 51 is twice as long as an excitation phase switching time t1 of the pulse motor 50, and the rotation speed of the pulse motor 51 is 1/2, and the ratio of the movement speed of a lamp 23 and a mirror 24 of a carriage 40 to that of a mirror 26 of a carriage 41 is 2:1. During a time T2, since the repeat period of clocks C is shorter, pulse motors 50 and 51 are rotated reversely in speeds higher than those for said positive rotation, and return times of mirrors 24 and 26 to original positions are shortened, and the ratio of the movement speed of the mirror 24 to that of the mirror 26 is kept in 2:1. |
