MAIN SCANNING MAGNIFICATION ERROR ADJUSTING METHOD IN MULTI-BEAM SCANNING DEVICE, MULTI-BEAM SCANNING DEVICE, IMAGE FORMING DEVICE, COMPUTER PROGRAM AND RECORDING MEDIUM

摘要

PPROBLEM TO BE SOLVED: To suppress abnormal images even if magnification errors happen in two or more scanning lines, even while using conventional optical elements. PSOLUTION: A multi-beam scanning device has a first and second LDs 12, 13 which emit two or more light beams for the image signals and can be independently modulated, a revolving polygon mirror 7 which changes the above beams from these first and second LDs 12, 13 into equal angular speed, and scanning imaging lenses 8-10 for converging the beams deflected by this revolving polygon mirror 7 to the scanning surface and scanning its surface at uniform speed. The multi-beam scanning device of this invention picks up the following second LD13 out ot the first and second LDs 12, 13, and corrects the timing of the following second LD 13 so that it is within the predetermined main scanning pitches by using the timing of the preceding first LD12 as the reference. Thus, it reduces the dot position displacements caused by color aberrations and the main scanning magnification errors caused by assembly errors of the above scanning imaging lens means. PCOPYRIGHT: (C)2005,JPO&NCIPI