| 摘要 |
PURPOSE: To improve corrective precision in the case of performing electric correction of an fθerror. CONSTITUTION: This scanner is provided with a reference signal generator 31 generating a reference signal of which level continues to increase gradually a storage device 32 storing the correction data for deciding drive pulse widths of respective pixels in a scan for correcting the fθerror, a D/A converter 34 converting the correction data read out from the storage into an analog signal, a comparator 35 comparing the level of the reference signal with the level of the analog signal and a write-out position detection signal S initializing the reference signal generator 31 for every scan, and a reference pixel clock Vclk is generated from the comparator 35 at the timing of the level of the reference signal becomeing larger than the level of the analog signal, and a laser driver 36 on/off-controls a laser diode 37 at the timing of the reference pixel clock based on the image data. |
