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5. White Balance Adjustment
5.1. Overview
5.1.1. W/B adj. Objective & How-it-works
(1) Objective: To reduce each Panel's W/B deviation
(2) How-it-works: When R/G/B gain in the OSD is at 192, it
means the panel is at its Full Dynamic Range. In order to
prevent saturation of Full Dynamic range and data, one of
R/G/B is fixed at 192, and the other two is lowered to find
the desired value.
(3) Adj. condition: normal temperature
1) Surrounding Temperature: 25 °C ± 5 °C
2) Warm-up time: About 5 Min◦
3) Surrounding Humidity: 20% ~ 80%
4) Before White balance adjustment, Keep power on
status, don't power off.
5.1.2. Adj. condition and cautionary items
(1) Lighting condition in surrounding area surrounding lighting
should be lower 10 lux.
Try to isolate adj. area into dark surrounding.
(2) Probe location: Color Analyzer(CA-210) probe should be
within 10 cm and perpendicular of the module surface.
(80°~ 100°)
(3) Aging time
1) After Aging Start, Keep the Power ON status during 5
Minutes.
2) In case of LCD, Back-light on should be checked using
no signal or Full-white pattern.
5.2. Equipment
(1) Color Analyzer: CA-210(NCG:CH9/ WCG:CH12/ LED:CH14)
(2) Adj. Computer(During auto adj., RS-232C protocol is needed)
(3) Adjust Remote control
(4) Video Signal Generator MSPG-925F 720p/204-Gray
(Model: 217, Pattern: 49)
* Color Analyzer Matrix should be calibrated using CS-1000.
5.3. Equipment connection
Probe
RS -232C
Signal Source
* If TV internal pattern is used, not needed
** RS-232C Connection Method.
LB45S/LB45R/LB45N → RGB cable → UART Jig →
RS232C cable and USB AM-BM cable → PC(RS232C Port)
Copyright ©
LG Electronics. Inc. All rights reserved.
Only for training and service purposes
5.4. Adjustment Command (Protocol)
RS-232C COMMAND
CMD
wb
wb
5.5. Adjustment method
5.5.1. Auto WB calibration
Co lo r Analyzer
5.5.2. LED White balance table
RS -232C
Co m p ut er
RS -232C
Pat t ern Generat o r
- 10 -
(1) RS-232C Command used during auto-adj.
DATA
ID
00
00
Begin White Balance adjustment
00
ff
End White Balance adjustment(internal pattern disappears)
(2) Adjustment Map
Command
Adj. item
(lower caseASCII)
CMD1
R Gain
j
G Gain
j
B Gain
j
Cool
R Cut
G Cut
B Cut
R Gain
j
G Gain
j
B Gain
j
Medium
R Cut
G Cut
B Cut
R Gain
j
G Gain
j
B Gain
j
Warm
R Cut
G Cut
B Cut
(1) Set TV in ADJ mode using P-Only key(or POWER ON key).
(2) Place optical probe on the center of the display. - It need to
check probe condition of zero calibration before adjustment.
(3) Connect RS-232C Cable
(4) Select mode in ADJ Program and begin a adjustment.
(5) When WB adjustment is completed with OK message, check
adjustment status of pre-set mode.(Cool, Medium, Warm)
(6) Remove probe and RS-232C cable.
▪ W/B Adj. must begin as start command "wb 00 00" , and
finish as end command "wb 00 ff", and Adj. offset if need.
- If Model is Polaris Model, G-gain fix is applied.
(1) Cool Mode
1) Purpose : Especially G-gain fix adjust leads to the
luminance enhancement. Adjust the color temperature
to reduce the deviation of the module color temperature.
2) Principle: To adjust the white balance without the saturation,
- Adjust the G gain more than 172 (If R gain or G gain is
more than 255, G gain can adjust less than 172) and
change the others(R/B Gain).(20LB45X model)
- Fix the G gain to 172(default data) and change the
others(R/B Gain).
3) Adjustment mode : mode - Cool
(2) Medium / Warm Mode
1) Purpose : Adjust the color temperature to reduce the
deviation of the module color temperature.
2) Principle: To adjust the white balance without the saturation,
- In Medium mode, Fix to G gain to 192 and change the
others(R/B Gain)(20LB45X model)
- Fix the one of R/G/B gain to 192(default data) and
decrease the others.
3) Adjustment mode : Two modes - Medium / Warm
Explanation
Data Range
Default
(Hex.)
(Decimal)
CMD2
MIN
MAX
g
00
C0
172
h
00
C0
192
i
00
C0
192
64
64
64
a
00
C0
192
b
00
C0
192
c
00
C0
192
64
64
64
d
00
C0
192
e
00
C0
192
f
00
C0
192
64
64
64
LGE Internal Use Only
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