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Lights are radiated to an original by the scanner lamp, and the con-
trast of the reflected lights is read by the CCD elements of the RGB
lines to convert it into the image signal (analog).

The RGB components of original images are extracted by three kinds
of CCD elements (RGB). The red CCD extracts the red components,
the green CCD the green components, and the blue CCD the blue
components. This is called color separation.

The CCD elements seem to be one unit apparently. However, there
are three kinds of CCD elements; R, G, and B.

Scanning of originals in the main scanning direction is performed by
the CCD elements. Scanning of originals in the sub scanning direction
is performed by the scanner unit driven by the scanner motor.

The original images are optically reduced by the lens and projected to
the CCD.

The scanning resolution is 600dpi.

1) Each image signal (analog) of R, G, and B is converted into 8bit

digital signal by the A/D converter. Each color pixel has 8bit infor-
mation (256 gradations).

2) Each 8bit digital image signal of R, G, and B is sent to the image

process section.

Zooming in the sub scanning direction is performed by changing the
scanning speed in the sub scanning direction.

Zooming in the main scanning direction is not performed optically, but
performed by the image process technology (by software).

∗

The scanner lamp is controlled (driven) by the scanner lamp
control PWB.

∗

The CCD PWB is controlled by the ICU MAIN PWB. Power is
supplied from the CCD power PWB to the CCD PWB.

∗

The scanner motor is controlled (driven) by the scanner motor
control PWB.

∗

The scanner unit position is detected by the scanner home position
sensor to control timing of various operations.

∗

The shading sheet is used as the reference reflection plate in
shading.

3 LINES CCD UNIT

R,G,B Color filter

CCD ELEMENTS

Red component

image data

Green component

image data

Blue component 

image data

CCD PWB

CCD ASIC

B ADC

B

Color
3-line

CCD

B analog IC

G analog IC

R analog IC

G ADC

R ADC

R

G

B

R

G

AR-C150

2 – 11

This section is composed of the scan ICU PWB, the CPT PWB image ICU PWB, the main ICU PWB, and the CCD PWB.

Each 8bit digital image signal of R, G, and B outputted from the scanner (reading) section is subject to various image processe s and corrections to
sent to the scanner (writing) section.

IMAGE PROCESS 1

SHADING CORRECTION / WHITE BLANCE ADJUSTMENT / 
DARK COMPONENT CORRECTION / GAMMA CORRECTION / 
MTF CORRECTION / R,G,B TIMING CORRECTION

FORGERY JUDGMENT

IMAGE PROCESS 2

HISTOGRAM PROCESS

AREA SEPARATION(BLACK COLOR TEXT,DOT PATTERN,PHOTO IMAGE

JUDGMENT

PRODUCE BLACK COLOR

COLOR CORRECTION(COLOR BALANCE ADJUSTMENT)

ZOOMING

FILTER PROCESS

HALF TONE PROCESS(GAMMA CORRECTION / CPT PATTERN OUTPUT)

IMAGE PROCESS 3

OUT PUT PROCESS(CONVERT COLOR IMAGE DATA
TO LASER BEARM DATA / ADJUST OUTPUT TIMING)

SCAN ICU PWB

IMAGE ICU PWB

MAIN ICU PWB

CPT PWB

INPUT PROCESS(GAMMA ADJ / COLOR CONVERT (R,G,B 

→

 Y,M,C)/

R

G

B

R

G

B

R

G

B

CCD PWB

CN1

CN2

CN3

CN537(8pin)

SCN

CN506(8pin)

MAIN

CN514(6pin)

IMG

ICU SECTION

CN506(9pin)

CCD P/S PWB

PCU PWB

CN535

(32pin)

CN103

(18pin)

DCPS

CN702

(40pin)

CN702

(40pin)

CN703

(8pin)

CN103

(18pin)

CN536

(30pin)

AR-C150

2 – 12

ICU-MAIN PWB

ICU-IMG PWB

ICU-SCN PWB

G

PCU PWB

CCD PWB

CCD ASIC

B ADC

B

VIF

Color

3-line

CCD

B analog IC

G analog IC

R analog IC

G ADC

R ADC

R

G

R

Area 

separation B

ASIC

Area

separation A

ASIC

Area

separation C

ASIC

Black

generation

ASIC

Intermediate

adjustment

ASIC

LSU

ASIC

LSU

ASIC

ROM

Tandem memory

Tandem memory

R SCN

ASIC

PWM

Differential

IC

LSU K

LSU Y

LSU C

LSU M

R

B

G SCN

ASIC

B SCN

ASIC

B

C

M

G

Y

C

M

Y

C

M

Y

K

C

M

Y

C

K

M

Y

C

K

M

Y

C

K

M

Y

Color

correction

 ASIC

Color

correction

 ASIC

Color

correction

 ASIC

ROM

ROM

K

Y

M

C

ARC150 only

(OP)

PRT I/F

ARC150 only

(OP)

PRT CTRL

R

G

B

K

Y

M

C

K

Y

M

C

PWM

PWM

PWM

K

Y

M

C

K

Y

M

C

K

Y

M

C

FMEM

FMEM

R

G

B

CPU

EEPROM

SRAM

FROM

CPUC

Synchronous S10

Synchronous S10

Asynchronous S10

VCO

VCO

Synchronous

IC

Synchronous

IC

Synchronous

IC

Synchronous

IC

VCO

VCO

Input

processing

ASIC

Area

separation D

ASIC

Synchronous

IC

Color

correction

 ASIC

AR-C150

2 – 13

1) Converts images (photo signals) into electric signals (analog). 

2) Color separation

3) Converts analog signals into digital signals.

1) Shading correction

2) White balance correction

3) Dark component correction

4) Gamma correction

5) R/G/B signal timing correction

1) Input process (Gamma table process, color conversion (R/G/B ?

Y/M/C), histogramprocess)

2) Area separation (Black character judgement, dot judgement,

photo judgement)

3) Color correction (Color balance correction)

4) Zooming

5) Filter process

6) Half tone process (Gamma correction, CPT pattern output)

1) Output process (Converts color image data into laser beam sig-

nals, adjusts the laser output timing.)

2) All ICU sections control

3) Data communication with PCU MAIN PWB

1) CPT judgement (Forgery prevention judgement)

Operation, function, and processing of CCD PWB section

Section

Operation, function, and processing

Unit or device

NOTE

CCD PWB Image is broken

down to R, G, and
B components,
converted to
electrical signals,
and output

Scans original image separately for each
color R, G, and B (color separation)

CCD

Controls image signal gain

CPU C

Analog IC (amplifier)

A/D conversion (converts image analog
signal to digital signal)

8bit 

×

 3 (R, G,

and B) data

CCD ASIC

A/D converter

Controls CCD (clock generation, timing
control)

Original images are separated into R, G, and B images.
         Original image

                   Blue image

                   Red image

                Green image

Operation, function, and processing of ICU SCAN PWB section

Section

Operation, function, and processing

Unit or device

NOTE

ICU SCAN
PWB

Image correction

White balance processing and
dark component correction

SCAN ASIC

SCAN ASIC internal
memory

Shading correction
Gamma correction (match
gamma for R, G, and B)

Refers to set table
according to the CCD
gamma correction chart

CPU C

MTF correction
RGB color correction (special
function/color adjustment mode)
Single color (special
function/image editing mode)
Line shift correction

Matches the R, G, and B
lines

Filed memory/FIFO

CPT PWB

CPT judgment

Recognizes paper width
and prohibits copying
operation

(For shading correction, white level correction, and dark component correction, refer to Chapter 3 (Image forming section correction operations).)

AR-C150

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