LASER BEAM SCANNING DEVICE

摘要

PURPOSE:To correct the unevenness of a pitch without using an (ftheta) lens or an (arc-sin) lens by electrically correcting it. CONSTITUTION:This is the laser light scanning device where a rotary polygon mirror 2 is disposed at the focusing position 1a of a parabolic mirror 1 and which emits a laser beam 9 emitted from a laser diode 3 and made incident on the mirror 2 according to the rotation of the mirror 2, makes the emitted beam incident on the mirror 1 and outputs collimated luminous flux from the mirror 1. The sequence Tn=2arctan(c/t) is stored in a memory 7 and a clock outputted from a clock circuit 4 is counted by a counter 5. When it is decided by a coincidence detection circuit 8 that the sequence Tn stored in the memory 7 and the counted value of the counter 5 coincide with each other, a sampling signal for turning on a laser diode is outputted from the detection circuit 8.