| 摘要 |
PURPOSE:To accurately detect the laser beam position even if the intensity of a laser beam varies by delaying a signal form a beam detector by a time set in accordance with the intensity of the laser beam. CONSTITUTION:The beam detector 33 outputs a signal having a pulse width corresponding to the intensity of a laser beam. Such an output signal goes through a dely circuit 34 whose delay time is set by a delay time setting circuit 37 corresponding to the detection output from a beam intensity detector 38 that detects the beam intensity beforehand and outputs the said output; after delaying by the said time, the output signal is inputted to a count permission signal generating circuit 35. A counter 36 starts counting by the signal from this circuit 35, and at a time point of the prescribed counting is reached, a print start signal is outputted. With the above-mentioned constitution, the print start timing can be accurately set even if the intensity of the laser beam varies, and as a result, an image excellent in quality can be obtained.
|
