Image Processing Circuit - Toshiba DP1600 Service Manual

6.2 Image Processing Circuit

(1) Outline
This digital copier scans optically the original placed on the original glass and reads an original image
using the CCD (charge coupled device), and converts the image into electrical signals. The electrical
signals are A/D converted into digital signals and output from the CCD board as image signals. The
image signals from the CCD board are input to the image processing section where shading correc-
tion (compensation for variance in the CCD or the light source) and various image-processing opera-
tions are performed. The results are output to the printer.
(2) Image Processing Circuit on the SLG Board
The SLG board contains an image processing ASIC which implements the following functions.
<Functions>
High quality image processing, image memory editing, editing processing, gamma correction pro-
cessing, tone processing and external output system interface
Image processing
section
: Image data flow
1600/2000/2500 IMAGE PROCESSING
CCD board
CCD
A/D conversion
SLG board
ASIC [ST.LOUIS]
Shading correction
High quality image processing,
image memory editing, editing
processing, gamma correction,
tone processing, and external
output systems interface.
MAIN board
ASIC [PTC]
External input systems interface
Image area control
Laser related control
Laser unit
Laser drive
Fig. 6-2-1
6 - 2
ASIC [EET]
Smoothing processing
Page memory
Memory copy, vertical/horizontal
alternate copy, sort copy, group
copy, magazine copy, simplex
reduction concatenation, duplex
reduction concatenation, image
combination, date annotation,
sheet insertion mode, etc.
December 2000 © TOSHIBA TEC
07002