Switching The Laser Activation Mode; Switching The Laser Output - Canon GP405 Service Manual

C. Switching the Laser Activation Mode
The laser beam is turned on for control of image signals and, in addition, for detection of BD
signals (full activation), selected using the laser activation mode switching signal (serial
communication) from the image processor PCB.
D. Switching the Laser Output
The laser output may be either high or low, and control is made so that images appropriate to
either mode may be obtained. The output modes are switched by changing the target voltage under
APC control in response to the laser output switching signal (serial communication).
These laser outputs are used as shown in Table 5-300:
Laser output
-610V
-585V
-560V
-530V
COPYRIGHT © 1999 CANON INC. CANON 405/335 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Low When low density is selected for memory copying.
High Other than above.
Laser output low
Lighter -2 -1
Copy density
[Memory Copying]
Figure 5-301
CHAPTER 5 LASER EXPOSURE SYSTEM
Mode
Table 5-300
Laser output high
0 1 2
Darker
5-7