Canon LBP-1210 Service Manual page 114

CHAPTER 2
IV. LASER/SCANNER SYSTEM
A. Outline
The laser/scanner unit is structured with the laser driver, the scanner motor, etc. It is con-
trolled by the signals input from the engine controller and the interface controller.
The laser driver forces the laser diode to emit according to the LASER CONTROL (CNT0,
CNT1) signals output from the engine controller and the VIDEO (/VDO, VDO) signals output
from the interface controller.
The laser beam emitted from the laser diode passes through the collimator and cylindrical
lenses and strikes the four-sided scanning mirror rotating at a constant speed. The laser beam
reflects off the scanning mirror, passes through the focusing lens and reflective mirror, and then
focuses on the photosensitive drum.
The laser beam finally forms a latent image on the drum, rotating at a constant speed, by
scanning across the drum and with the scanning mirror also rotating at a constant speed.
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