CONTROLLER FOR EXPOSURE START OF PRINTER

PURPOSE:To obtain an accurate transfer position of a print image, by providing a detector which detects the pass position of the printing paper which is being fed or transported and a means which starts the exposure in a prescribed period of time after a detecting signal is received from the detector. CONSTITUTION:The controller is provided with a paper pass position detector 20, a counter 21 and a printer controller 22. When the printing paper 2 passes the position of the detector 20, the detector 20 delivers an output to the counter 21. Thus the counter 21 starts its operation. The controller 22 transmits an exposure signal to a laser device 19 synchronously with the output timing of the counter 21. Then the exposure is started. In such constitution, no shift is produced for the transfer position of a printer although the paper feed has a timing delay and the transport of the paper 12 has a delay between a paper feed belt 4 and a conveyor belt 8.