Optical System; Ii. Optical System; Outline - Canon CANOSCAN N1220U Service Manual

CHAPTER 2

II. OPTICAL SYSTEM

A. Outline
The optical system includes the functions of moving the scanning unit by the drive motor,
exposing a document by the LED, and collecting the reflected light to the phototransistor array.
Contact image sensor is adopted for the scanning unit, which is a module combined with the
LED for light exposing, the lens array for light collecting, and the phototransistor array for light
receiving to read per line. The drive motor runs by the drive signal sent from the main PCB
and drives the scanning unit via the drive pulley and drive wire.
Sliding rod
Contact image sensor
Drive wire
Drive motor
Drive pulley
Figure 2-8
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COPYRIGHT 2000 CANON INC. CANOSCAN N650U/N656U/N1220U REV.0 JUNE 2000 PRINTED IN JAPAN (IMPRIME AU JAPON)