| 摘要 |
PROBLEM TO BE SOLVED: To minimize the frequency of measuring the time difference when a laser beam is detected at two points on the main scanning line and the magnification of an image formed on a photosensitive body is corrected based on the time difference. SOLUTION: The imaging apparatus comprises sensors 14 and 15 for detecting a laser beam 26 being deflected by a polygon mirror 3 at two points on the main scanning line, and a temperature sensor 27 for detecting the temperature of an fθlens 4. When a detected temperature variation exceeds a specified value, a magnification correcting section 22 measures the beam detection time difference of the sensors 14 and 15 and controls the frequency of a reference clock CLK depending on the time difference. Frequency of a drive clock VCLK at the LD drive section 24 of an LD unit 25 generating a laser beam is thereby controlled and the magnification of an image formed on a photosensitive body 7 is corrected in the main scanning direction. |
