Zenith D52WLCD Series Service Manual page 32

(4) Adjustment Sequence
Gamma Adjust Mode
1 80 100 100
2 234 216 216
3 453 411 387
16 724 740 780
RGB 456 Step123
1) Output the 255,255,255 signal of VDP Test Pattern, then
display the maximum white pattern on screen.
2) Gamma Adjust Mode is display as below when select
8.Gamma Data by selecting IN-START key on SVC
remote control.
3) Change the 16 Step RGB Data to select white balance
x=283, y=294.
[ The color coordinates are set to x:283, y:297 in actual
video signal, when the color coordinates are x:293, y:294
in VDP Pattern.
4) Measure the luminace with changed data.
5) Set the Gamma data of 16 step to 2.5 on the basis of
measured luminance data in 3).
(Max luminance *(n1/16)**2.5) — Max luminance : mea-
sured luminance data n1 = every step unit when separat-
ing 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 show white balance x=283, y=294 and
measured step luminance in 5).
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 show white balance x=283, y=294 and
measured step luminance in 5).
8) As shown above, output the VDP Test Pattern sig-
nal(208/192/176/160/144/128/112/96/80/64/48/32/16) and
change the RGB Data value of each step to show white bal-
ance x=283, y=294 and measured lumincance in 3).
(5) Gamma adjustment manually
This adjustment(after finish the 3-4) is to check whether
Gamma/White Balance adjustment are well adjusted and
make correction manually.
1) Prepare the PC Pattern Generator to output R/G/B of 16
step and 64 step Gray Pattern.
2) Equipment composition : Follow Fig. 2.
3) Turn on the Jig for adjustment.
4) Select the RGB_PC by pressing the input select button on
Remote Control.
5) Output the 16 Gray Pattern in PC Pattern Generator.
Check it with the naked eye whether Screen Gamma and
W/B is right about each Gray.
If it's not, press the IN-START button on SVC Remote
Control and then adjust the level data of each step manu-
ally in sub menu of No. 8.Gamma Data.
ADJUSTMENT INSTRUCTIONS
* 1st Column : 16 Step Level
* 2nd Column : R Adjustment
Data
* 3rd Column : G Adjustment
Data
* 4th Column : B Adjustment
Data
6) Output the 64 Gray Pattern in PC Pattern Generator.
Check it with the naked eye whether Screen Gamma and
W/B is right about each Gray or whether there is Gamma
noise.
If there's any problem, adjust in 5).
7) After finishing adjustment, exit adjustment mode by using
IN-START button on SVC Remote Control.
5-5. White Uniformity Adjustment
(1) Required Test Equipments
1) Uniformity measurement equipment : Equipment which can
measure chromaticity in the whole screen
2) Set Stand 1EA
3) Remote Control for Adjustment
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 1 level form 0 to 255 level.
(2) A equipment composition
Compose the equipment follow Fig. 2 and place the set on
the fixation stand.
(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 color uniformity
like Horizontal/Vertical position adjustment of input signal
part adjustment by using Remote Control for adjustment.
3) After pressing IN-START key on SVC Remote Control for
adjustment, select the adjustment mode 5.7050 Uniformity.
Refer to register value and correct register value if need.
<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 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)
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