Color Gradation Corrective Control - Canon i-SENSYS LBP5300 Series Service Manual

2.4.2.3 Color gradation corrective control

/ i-SENSYS LBP5360 / i-SENSYS LBP5300
This control is utilized to measure the halftone image density and to send the measurement results to the video controller to calibrate the color gradation.
This printer detects the density of all four colors' pattern images for color gradation correction formed on the ETB in order to adjust the image density.
This density detection is performed by the DC controller controlling the color misregistration/image density sensor during the environment related corrective control
and measuring image density. The color misregistration/image density sensor which is light emitter (LED) and light receiver (PD) pairing. A pair of the sensors are
equipped above the ETB.
<Normal operation>
Video controller PCB
DC controller PCB
Environment
sensor
F-2-19
Color misregistration/
Image density sensor (R)
Pattern images for color gradation correction
(The right one is darker than the left one)
F-2-20
VIDEO controller PCB
DC controller PCB
COLOR MISREGISTRATION
/IMAGE DENSITY signal
COLOR MISREGISTRATION/
IMAGE DENSITY DETECTION LED DRIVE signal
Color misregistration/
Image density sensor (L)
ETB
Chapter 2
0013-7577
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