Canon FAX-L1000 - Manual (Page 192)

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FAX-L1000 Chapter 3: Technical Reference
2.5.2 LASER/Scanner section
a) Functions
Figure 3-17 LASER/Scanner Section
The VIDEO signal (nVDO) is sent from the SCNT board to the laser driver of the laser/
scanner unit through the TWINS board and ECNT board.
The laser driver turns the laser diode ON and OFF according to the nVDO signal and
generates the modulated laser beam only when the VIDEO DATA ENABLE (nENBL)
signal from the ECNT board is “L.”
The modulated laser beam is aligned by a collimator lens and a cylindrical lens into a
parallel beam. It then strikes the scanning mirror which is rotating at a constant speed.
The beam reflected from the scanning mirror is brought to a point of focus on the
photosensitive drum by the focusing lens and mirror.
As the scanning mirror rotates at a constant speed, the beam is scanned across the drum at a
constant speed.
The photosensitive drum also rotates at a constant speed allowing the laser beam to form an
image on the drum surface.
Laser driver
Cylindrical lens
Scanner motor
Scanning mirror
Focusing lens
BD mirror
Mirror
SCNT
board
ECNT
board
/BD
/TOP
/VDO
/ACC
/DEC
HALF
/LON
/ENBL
/VDO
/BDI
TWINS
board