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5.3. White Balance Adjustment
5.3.1. Overview
5.3.1.1. 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 °C
- Warm-up time: About 5 Min
- Surrounding Humidity: 20% ~ 80%
- Before White balance adjustment, Keep power on status,
don’t power off
5.3.2. Equipment
(1) Color Analyzer: CA-210 (LED Module : CH 14)
(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
5.3.3. Equipment connection
5.3.4. Adjustment Command (Protocol)
<Command Format>
START 6E A 50 A LEN A 03 A CMD A 00 A VAL A CS A
STOP
- LEN: Number of Data Byte to be sent
- CMD: Command
- VAL: FOS Data value
- CS: Checksum of sent data
- A: Acknowledge
Ex) [Send: JA_00_DD] / [Ack: A_00_okDDX]
▪ RS-232C Command used during auto-adj
RS-232C COMMAND
Explanation
CMD
DATA
ID
wb
00
00
Begin White Balance adj.
wb
00
10
Gain adj.(internal white pattern)
wb
00
1f
Gain adj. completed
wb
00
20
Offset adj.(internal white pattern)
wb
00
2f
Offset adj. completed
Wb
00
ff
End White Balance adj.
(internal pattern disappears )
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(endc)) -> Off-set adj.
wb 00 ff ->End white balance auto adj.
▪ Adj. Map
Adj. item Command
(lower caseASCII)
Data Range
(Hex.)
CMD1
CMD2
MIN
MAX
Cool
R Gain
j
g
00
C0
G Gain
j
h
00
C0
B Gain
j
i
00
C0
Medium
R Gain
j
a
00
C0
G Gain
j
b
00
C0
B Gain
j
c
00
C0
Warm
R Gain
j
d
00
C0
G Gain
j
e
00
C0
B Gain
j
f
00
C0
5.3.5. Adjustment method
5.3.5.1 Auto WB calibration
(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
Color Analyzer
Computer
Pattern Generator
※
Signal Source
Probe
RS-232C
RS-232C
RS-232C
※
If TV internal pattern is used, not needed
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