Epson Perfection 4870 Photo Service Manual page 25

Perfection 4870 Photo
Film-Ice function sequence
1. Read the visible light position (To recognize the home position of image scanning, it
reads two holes of the Upper Housing Scale section).
2. Scan a visible-light image.
3. Scan an infrared-light image.
4. Superimposes the images obtained from each light and detects the flaws and/or the
foreign matter.
5. Erases the flaws and/or the foreign matter on the hardware, which have been detected
in the step 4 and obtains the image without any flaw and/or foreign matter.
Dirt extraction
Figure 2-8. Extraction/Correction of Dust by Film-Ice Function
OPERATING PRINCIPLES
After correction
Digital Ice function operation
Revision A
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