4) The DC controller monitors the rotational speed of the scanner motor with the /BDI signals input timing to control the scanner motor to rotate at constant speed.

When the scanner motor rotates at constant speed, the DC controller outputs the video signals sent from the main controller to the laser driver PCB.

5) In the laser driver PCB, the laser diode is emitted depending on the video signals and the laser beam is radiated.

6) The laser beams are reflected by the polygon mirror rotating at the constant speed, and reach the photosensitive drum via the focusing lens and the reflection

mirror.

The focusing lens corrects the route of the laser beam to maintain the constant scanning speed on the photosensitive drum.

7) When the photosensitive drum rotates at constant speed and the laser beams scan vertically to its rotation, a latent image is formed on the drum.

MEMO:

- Only one /BDI signal is generated per scanner motor.

The /BDI signals of the scanner motor for M/C is generated based on the M laser reflected light, and the /BDI signals of the scanner motor for Y/Bk is generated

based on the Y laser reflected light.

The DC controller generates the /BDI signals for four colors according to these /BDI signals and send them to the main controller.

- The machine scans two lines with one polygon mirror. Therefore the scanning direction depends on the color. (The direction for M/Y is right-end write start

scanning direction and that for C/Bk is left-end write start scanning direction relative to the print side of paper.)

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