White Balance Adjustment - LG 47LM5800 Service Manual

5. Final Assembly Adjustment

5.1. White Balance Adjustment

5.1.1. Overview
5.1.1.1. 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
- Surrounding Temperature: 25±5 ºC
- Warm-up time: About 5 Min
- Surrounding Humidity: 20% ~ 80%
- Before White balance adjustment, Keep power on status,
don't power off
5.1.1.2. 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 10cm and perpendicular of the module surface
(80°~ 100°)
(3) Aging time
- After Aging Start, Keep the Power ON status during 5
Minutes.
- In case of LCD, Back-light on should be checked using no
signal or Full-white pattern.
5.1.2. Equipment
(1) Color Analyzer: CA-210 (NCG: CH 9 / WCG: CH12 / LED:
CH14)
(2) Adj. Computer(During auto adj., RS-232C protocol is
needed)
(3) Adjust Remocon
(4) Video Signal Generator MSPG-925F 720p/204-Gray
(Model:217, Pattern:49)
→ Only when internal pattern is not available
※ Color Analyzer Matrix should be calibrated using
CS-1000
5.1.3. Equipment connection
Probe
RS-232C
Signal Source
※If TV internal pattern is used, not needed
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
Color Analyzer
RS-232C
Computer
RS-232C
※
Pattern Generator
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5.1.4. Adjustment Command (Protocol)
(1) RS-232C Command used during auto-adj
RS-232C COMMAND
CMD DATA ID
Wb 00 00 Begin White Balance adj.
Wb 00 ff End White Balance adj.
(internal pattern disappears )
(2) Adjustment Map
Command
(lower case ASCII)
Adj. item
CMD1
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
Explanation
Data Range Default
(Hex.) (Decimal)
CMD2 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
LGE Internal Use Only