Image Quality Control - Toshiba e-studio550 Service Manual

11. 4. Image Quality Control

11. 4. 1. General description
This copier carries out the image quality control with the image quality sensor. The image quality control
is for changing the image formation condition to minimize the changing of the image density and line
width caused by the environment and life.
The image quality sensor detects the density of the test pattern developed on the drum, and the image
formation condition is changed depending on the result.
11. 4. 2. Principle of sensor
The image quality sensor applies the light to the drum and toner image (test pattern) developed on the
drum and outputs the voltage corresponding to its reflected light amount.
A relative reflectivity is assessed by the reflected light amount obtained by the image quality sensor.
Light emitting element
Test pattern
(toner image)
JUNE 2002 © TOSHIBA TEC
Image quality sensor
Light sensing element
Drum
Light source intensity signal
Reflected light intensity signal
11 - 3 e-STUDIO550/650/810 DRUM/CLEANER UNIT