LG 55LH80YD, Service Manual

Page: 13 / 66

5.1. White Balance Adjustment
5.1.1 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.
5.1.2 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
5.1.3 Equipment connection
5.1.4 Adj. Command (Protocol)
- LEN : Number of Data Byte
- CMD : Command
- VAL : Value of FOS Data
- CS : Checksum
- A : Acknowledge
Ex) [Send: JA_00_DD] / [Ack: A_00_okDDX}
• RS-232C Command(Automatic adjustment)
Ex) wb 00 00 : Start Auto-adjustment of white balance.
wb 00 10 : Start Gain Adjustment (Inner pattern)
ja 00 ff : Adjustment data
jb 00 c0 :
…
wb 00 1f : End of Gain adjustment
* (wb 00 20(start), wb 00 2f(end)) -> In the case of Off-
set adjustment
wb 00 ff : End of white balance adjustment
• Adjustment Map
5.2. Adjustment of White Balance
5.2.1 Automatic Adjustment
1) The adjustment condition should be set by the Power On
key.
2) Perform the zero calibration of the Color Analyzer and
place the probe close to the display center.
3) Connect the communication cable (RS-232C).
4) Select the desired model of the adjustment program and
perform the adjustment.
5) After the adjustment is ended (check the OK sign), check
the adjustment condition for each mode of the set.
(Warm, Medium, Cool)
6) Disconnect the probe and the communication cable to end
the adjustment.
* The adjustment should be started with "wb 00 00" and
ended with "wb 00 ff", and the offset should be adjusted
when necessary.
5.2.2 Manual adj. method
1) Set TV in Adj. mode using POWER ON
2) Press the ADJ of the R/C to enter into ‘EZ-ADJUST’.
3) Select ‘10.TEST PATTERN’ with the CH +/- key and press
the Enter key for 30 minutes or longer to perform the heat
run.
4) Perform the zero calibration of the Color Analyzer and fix
the sensor with the 10cm or less distance at the center of
the LCD module surface when adjusting.
5) Press the ADJ of the R/C to select ‘7.White-Balance’ of the
Ez-Adjust and press the right arrow key(
G
) to enter into the
adjustment mode. (As soon as you press ‘
G
’, the screen is
entered into the full white inner pattern.)
6) Fix one of the R/G/B gains to 192 and decrease the
remaining two gains to adjust not to exceed 192.
7) The adjustment is done at three white balances of Cool,
Medium and Warm
- 13 - LGE Internal Use Only Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Co lo r An alyzer
Co m p ut er
Pat t ern Gen erat o r
RS -232C
RS -232C
RS -232C
Probe
Signal Source
* If TV internal pattern is used, not needed
Connection Diagram of Automatic Adjustment
START 6E 50 03 00 CS LEN CMD VAL STOP A A A A A A A A
RS-232C COMMAND
Meaning
[CMD ID DATA]
wb 00 00 White Balance adjustment start.
wb 00 10 Start of adjust gain (Inner white pattern)
wb 00 1f End of gain adjust
wb 00 20 Start of offset adjust(Inner white pattern)
wb 00 2f End of offset adjust
wb 00 ff End of White Balance adjust(Inner pattern disappeared)
ITEM Command Data Range Default
(Hex.) (Decimal)
Cmd 1 Cmd 2 Min Max
Cool R-Gain j g 00 C0 TBD
G-Gain j h 00 C0 TBD
B-Gain j i 00 C0 TBD
R-Cut TBD
G-Cut TBD
B-Cut TBD
Medium R-Gain j a 00 C0 TBD
G-Gain j b 00 C0 TBD
B-Gain j c 00 C0 TBD
R-Cut TBD
G-Cut TBD
B-Cut TBD
Warm R-Gain j d 00 C0 TBD
G-Gain j e 00 C0 TBD
B-Gain j f 00 C0 TBD
R-Cut TBD
G-Cut TBD