LG RT-44/48/52SZ50LP Service Manual page 17

1) Select the VDP Test Pattern signal to R1, G1, B1.
2) Press the Adjust key to select 62352 and then select
RVREF, GVREF, BVREF in adjust mode
3) Adjust the luminance of CA100 to be below 0.75Cd by
volume key.(Range : 196~ 202)
4) Exit adjustment mode by pressing Adjust key.
5) Press the IN-START key on the remote control and select
the 7050 RGB Set of adjustment mode and then press the
G
key.
6) Check the data value of Rcontast, Gcontrast, Bcontrast is
515, Otherwise set the data 515 by using volume key.
(4) Adjustment Sequence
1) Output 255,255,255 signal of VDP TEST PATTERN, then
display maximum WHITE PATTERN on screen.
2) Gamma Adjust Mode is display as below when select
Gamma adjust by pressing ADJ key on remote control.
Gamma Adjust
R:1 G:2 B:3
80 100 100
234 216 216
453 411 387
--------------------------
--------------------------
724 690 780
3) Change the 16 Step RGB data to select white balance
x:283, y:297(D9300K).[48inch - X:269, Y:294;11000K]
4) Measure the luminace with chanded data.
5) Set the every Gamma data of 16 step to 2.2 on the basis of
measured luminance data in 3)clause. (Max lumenance
*(n1/16)**2.2)
--- Max luminance : measured luminance data n1 : every
step unit when separating signal level to 16 step
6) Output the 240, 240, 240 (15th data in max white output
signal level) in the VDP Test Pattern, change the 15th RGB
data value to come out white valance x=283,
y=297(D9300K) and measured step luminance in 5)clause.
7) Output the 224, 224, 224 (14th data in max white output
signal level) in the VDP Test Pattern, change the 14th RGB
data value to come out white valance x=283, y=297 and
measured step luminance in 5)clause.
8) As shown above, output the VDP Test Pattern signal
(208/192/176/160/144/128/112/96/80/64/48/32/16) and
change the RGB data value of each step to come out white
balance x=283, y=294 and measured luminance in
3)clause.
10. White Uniformity Adjustment
(1) Required Test Equipments
1) Uniformity measuring equipment : Equipment which can
measure chromatiity in the whole screen
2) Set stand : 1EA
3) Remote controller for adjustment : 1EA
4) Circuit thing Jig for Adjustment (Except Driver Board Assy
of adjustment model)
--- Programmed Digital Board so that the VDP Test Pattern
can output white signal by 1level form 0 to 255 level.
(2) Equipment composition
Compose the equipment as Fig.2
*First column : R adjustment
data display
*Second column : G adjustment
data display
*Third column : B adjustment
data display
(3) Preparation for Adjustment
1) Composite the equipment as shown Fig.2, and place the
set on fixation stand.
2) After inputting company channel 13, adjust colour uniformity
like Horizontal/ Vertical position adjustment of input signal
part adjustment by using remote control for adjustment.
3) After pressing IN_START key on remote control for
adjustment, select the adjustment mode 7050 Uniformity.
<Resister Explanation about uniformity adjustment>
1. RamCtrl : s/w saving uniformity write order (Do not adjust)
2. CSHP : Horizontal start point designation --- adjustable
3. CSVP : Vertical start point designation --- adjustable
4. CEHP : Horizontal END point designation --- adjustable
5. CEVP : Vertical END point 6.designation --- adjustable
6. Mode : uniformity mode select --- adjustable if need
*** 0 : 221point & 3level ---- defalut value
*** 1 : 221point & 4level
*** 2 : 825point & 3level
*** 3 : 825point & 4level
7. KHH : Upper 2byte of horizontal line correction coefficient --
Change according to CSHP, CEHP value.
8. KHL : Upper 2byte of vertical line correction coefficient --
Change according to CSHP, CEHP value.
** How to calculate KHH, KHL value
LCD panel size = 1280 x 720
Correction Point = 221 point
--> 17 horizontal points x 13 vertical points
(16 horizontal segments x 12 vertical poins)
H Coefficient(KHH, KHL)
O
--> Calculation method (CEHP-CSHP=1280, Horizontal
segment value =16)
H coefficient = 1/(number of pixel intervals between setting in the horizontal
direction)
Hcoeff = 1/((1280/16)-1) = 0.012658227
hex (0.012658227 x 2
9. KVH : Upper 2byte of vertical line correction coefficient
-- Change according to CSVP, CEVP value.
10. KVL : Upper 2byte of vertical line correction coefficient
-- Change according to CSVP, CEVP value.
V Coefficient(KVH, KVL)
O
Calculation method (CEVP-CSVP=720, Vertical segment
value =12)
V coefficient = 1/(number of pixel intervals between setting in the vertical
direction)
Vcoeff = 1/((720/12)-1) = 0.016949152
hex (0.016949152 x 2
11. RL1H : Upper 9bit of MID2 brightness correction
coefficient in R MIN.
--- Change according to RMIN and RMID2 value.
12. RL1L : Lower 9bit of MID2 brightness correction coefficient
in R MIN.
--- Change according to RMIN and RMID2 value.
13. RL2H : Upper 9bit of MID1 brightness correction
coefficient in R MID2.
--- Change according to RMID2 and RMID1 value.
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16 ) = 0 x 033D, Hcoeff (hex) = 0 x 033D + 1 = 0 x 33E
16 ) = 0 x 0456, Vcoeff (hex) = 0 x 0456 + 1 = 0 x 0457