Canon 1000 Service Manual page 138

3. OPERATION AND TIMING
3. Controlling the Development Characteristics (SALT)
a. Outline
The printing density changes over time because of the following factors:
• Deterioration of the developer
• Deterioration of the photosensitive drum
• Changes in the environment
To make up for the changes, the density of the density pattern formed on the photosensitive drum is
measured by the SALT sensor, and the toner supply period is corrected based on the resulting
measurements.
Direct light intensity/
reflected light intensity signal
Bk
SALT sensor
Density pattern
Photo diode for reflected light
intensity/measurement
Photo diode for direct light
intensity measurement
3-94
COPYRIGHT © 2001 CANON INC.
Direct light intensity/
reflected light intensity signal
ATR sensor
C
SALT sensor
Figure 3-514
LED
Figure 3-515
CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
DC controller
Direct light intensity/
reflected light intensity signal
ATR sensor
M
SALT sensor
Transfer belt
Photosensitive drum
Shutter
Direct light intensity/
reflected light intensity signal
ATR sensor
Y
SALT sensor
Fulcrum
Shutter solenoid
(SL17Y, M, C, Bk)