Optics/Image Processing; Overview - Ricoh C226 Service Manual

2. OPTICS/IMAGE PROCESSING

2.1 OPTICS/IMAGE PROCESSING

2.1.1 Overview

C N 1 0 9
Contact Image
Amplification
Sensor
C N 1 0 1
Power Supply
P C B
GA2
C N 1 0 8
T h e r m a l
T h e r m a l
H e a d
H e a d
Drive
This model uses a Contact Image Sensor (CIS) instead of a CCD. This
removes the necessity of the complicated adjustments that are needed for a
CCD scanner.
There are 3 main chips on the main control board as shown. This model uses
a new type of halftone processing chip. The new halftone processor enables
the use of Letter/Photo mode in addition to Letter and Photo modes as the
Type of Original selection. In Letter/Photo and Photo modes, error diffusion
processing is used. This will produce a better copy quality of halftone images.
The new halftone processor also includes the A/D conversion function, not
only the image processing functions. The thermal head drive function is built
into the chip (GA2) on the main control board. Therefore, this model does not
have a separate A/D conversion board or thermal head board.
SM
Main Control PCB
A/D
Conversion
Letter/Photo
Image Area
Detection
Data
Compensation
M T F
Correction
Main-scan Direction
Clock Image Position
Adjustment
Overlay Data Selection
2-9
OPTICS/IMAGE PROCESSING
Half Tone Processor
Binary
Processing
Data
Selection
Error
Diffusion
GA1
Main
Centering
Control
Data
Selection
I m a g e
Enlargement/
Reduction
C226