| 摘要 |
PURPOSE:To guide a tip of a film certainly in setting up without exposing the film with beams when a light source is preparatorily lighted by a method wherein a slit is provided to a beam radiation part of an optical unit and at the same time, this slit is made capable of being opened and closed with a shutter. CONSTITUTION:When a printing command signal is inputted from a host computer, a main motor or the like is started and besides, a semiconductor laser is preparatorily lighted for t2 in time. It is for the purpose of regulating output of the semiconductor laser. In that case since a slit 211 is closed with a shutter 220, a film is never exposed to light. After t2 in preparatory lighting time has elapsed, a shutter solenoid is turned on, and the slit 211 is opened herein. Further, when t3 in time, however t3>t2, has elapsed from the input of the printing command signal, an image area assignment signal is turned off, and an SOS signal to determine an image writing start position with laser beams becomes capable of being received. |
