White Balance Adjustment - Sharp LC-20AV7U Service Manual

Item
remote control)
DR(C/D1)
[VOL -] → [4]
C-DR(C/D2)
DB(C/D1)
[VOL -] → [6]
C-DB(C/D2)
The following adjustment normally are not
attempted in the field. Only when replacing the
LCD Panel then adjust as a preparation.

2. White Balance Adjustment

Purpose: To mix red, green and blue beams correctly
for pure white.
Symptom of Misadjustment: White becomes bluish
or reddish.
Test Point Adj. Point
[RF/INPUT1]
[VOL -]
Screen
[INPUT2]
buttons
M. EQ.
Pattern Generator,
Color analyzer
Figure
It carries out in a darkroom.
Perpendicularity
L = 3 cm
INPUT: WHITE 80%, 20%
Note: Use the service remote control unit
1. Operate the unit for more than 20 minutes.
2. Input the White Purity.
3. Set the color analyzer to the CHROMA mode and
bring the optical receptor to the center on the
LCD-Panel surface after zero point calibration as
shown above.
Note: The optical receptor must be set
perpendicularly to the LCD Panel surface.
4. [RF/INPUT1]
Enter the Service mode. Press [VOL -] button on the
remote control unit and select "C/D1" mode.
Button
Data
(on the
Value
128
128
128
128
Mode Input
White Purity
C/D1 (APL 80%)
or
C/D2
(APL 20%)
Spec.
x= 0.278 ± 0.005
y= 0.286 ± 0.005
Color Analyzer
[INPUT2]
Enter the Service mode. Press [VOL -] button on the
remote control unit and select "C/D2" mode.
5. [RF/INPUT1]----(APL 80%)
Press [6] button to select "DB(C/D1)" for Blue
adjustment. Press [4] button to select "DR(C/D1)"
for Red adjustment. When "x" value and "y" value
are not within specification, adjust "DB (C/D1)" or
"DR (C/D1)". Refer to "1. Initial Setting."
[RF/INPUT1]----(APL 20%)
Press [3] button to select "COB(C/D1)" for Blue
adjustment. Press [1] button to select "COR(C/
D1)" for Red adjustment. When "x" value and "y"
value are not within specification, adjust "COB (C/
D1)" or "COR (C/D1)". Refer to "1. Initial Setting."
6. [INPUT2]----(APL 80%)
Press [6] button to select "C-DB(C/D2)" for Blue
adjustment. Press [4] button to select "C-DR(C/
D2)" for Red adjustment.When "x" value and "y"
value are not within specification, adjust "C-DB(C/
D2)" or "C-DR(C/D2)". Refer to "1. Initial Setting."
[INPUT2]----(APL 20%)
Press [3] button to select "C-COB(C/D2)" for Blue
adjustment. Press [1] button to select "C-COR(C/
D2)" for Red adjustment.When "x" value and "y"
value are not within specification, adjust "C-
COB(C/D2)" or "C-COR(C/D2)".
Refer to "1. Initial Setting."
7. Turn the power off and on again. (Main power
button on the TV unit.)
5-2 A7144EA