White Balance Adjustment - LG 32LD340H Service Manual

5.3. White Balance Adjustment

(1) Overview
• W/B adj. Objective & How-it-works
- Objective: To reduce each Panel's W/B deviation
- 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.
- Adj. condition : normal temperature
1) Surrounding Temperature: 25±5ºC
2) Warm-up time: About 5 Min
3) Surrounding Humidity: 20% ~ 80%
(2) Equipment
1) Color Analyzer: CA-210 (NCG: CH 9 / WCG: CH12)
2) Adj. Computer(During auto adj., RS-232C protocol is
needed)
3) Adjust Remocon
4) Video Signal Generator MSPG-925F 720p/216-Gray
(Model:217, Pattern:78)
-> Only when internal pattern is not available
• Color Analyzer Matrix should be calibrated using CS-1000
(3) Equipment connection MAP
Probe
RS -232C
* If TV internal pattern is used, not needed
Connection Diagram of Automatic Adjustment
(4) Adj. Command (Protocol)
1) RS-232C Command used during auto-adj.
RS-232C COMMAND
[CMD ID DATA]
wb 00 00 Begin White Balance adj.
wb 00 ff End White Balance adj.(Internal pattern disappeared)
Ex) wb 00 00 -> Begin white balance auto-adj.
wb 00 10 -> Gain adj.
ja 00 ff -> Adj. data
jb 00 c0
...
...
wb 00 1f -> Gain adj. complete
*(wb 00 20(start), wb 00 2f(end)) -> Off-set adj.
wb 00 ff -> End white balance auto adj.
Copyright LG Electronics. Inc. All right reserved.
Only for training and service purposes
Co lo r Analyzer
RS -232C
Co m p ut er
RS -232C
Pat t ern Generat o r
Signal Source
Meaning
2) Adjustment Map
Applied Model : LA06A Chassis All models.
ITEM Command
Cmd 1
Cool R-Gain j
G-Gain j
B-Gain j
R-Cut
G-Cut
B-Cut
Medium R-Gain j
G-Gain j
B-Gain j
R-Cut
G-Cut
B-Cut
Warm R-Gain j
G-Gain j
B-Gain j
R-Cut
G-Cut
(5) Auto adj. method
1) Set TV in adj. mode using POWER ON key
2) Zero calibrate probe then place it on the center of the
Display
3) Connect Cable(RS-232C)
4) Select mode in adj. Program and begin adj.
5) When adj. is complete (OK Sing), check adj. status pre
mode (Warm, Medium, Cool)
6) Remove probe and RS-232C cable to complete adj.
* W/B Adj. must begin as start command "wb 00 00" , and
finish as end command "wb 00 ff", and Adj. offset if need
(6) Manual adj. method
1) Set TV in Adj. mode using POWER ON
2) Zero Calibrate the probe of Color Analyzer, then place
it on the center of LCD module within 10cm of the
surface..
3) Press ADJ key -> EZ adjust using adj. R/C > 6. White-
Balance then press the cursor to the right (KEY
(When KEY(
will be displayed)
4) One of R Gain / G Gain / B Gain should be fixed at
192, and the rest will be lowered to meet the desired
value.
5) Adj. is performed in COOL, MEDIUM, WARM 3 modes
of color temperature.
- If internal pattern is not available, use RF input. In EZ
Adj. menu 6.White Balance, you can select one of 2
Test-pattern: ON, OFF. Default is inner(ON). By
selecting OFF, you can adjust using RF signal in 216
Gray pattern.
- 13 -
Data Range
(Hex.)
Cmd 2 Min Max
g 00 C0
h 00 C0
i 00 C0
a 00 C0
b 00 C0
c 00 C0
d 00 C0
e 00 C0
f 00 C0
G
) is pressed 216 Gray internal pattern
LGE Internal Use Only
Default
(Decimal)
G
).