Canon LBP-800 Manual Do Serviço

A. Outline
The microcomputer (CPU:201) on the engine controller sends the LASER CONTROL signals
(CNT0, CNT1) to the laser driver (IC801) on the laser driver PCB.  The VIDEO signals (/VDO,
VDO) from the interface controller are sent to the laser driver (IC801) on the laser driver PCB
through the engine controller.

The laser driver (IC801) emits the laser beam according to these signals sent from the engine

controller and interface controller.

The laser beam emitted form the laser diode passes though collimator lens and cylindrical

lens, and then strikes the four-faced scanning mirror rotating at a constant speed. 

The beam reflected from the four-faced scanning mirror passes through focusing lens and is

reflected onto the photosensitive drum.

When the photosensitive drum rotates, and at the same time, the laser beam scans across its

surface at a constant speed, the laser beam forms an latent image on the drum surface.

Cylindrical

lens

Laser

unit

Four-faced

scanning

mirror

Scanner motor

Focusing lens

BD sensor

Reflecting mirror

Photosensitive drum

Interface controller PCB

Engine controller PCB