LG RU-48SZ40 Service Manual page 17

<L Coefficient Calculation Method>
Using 3coefficient Level
Assume that the value of R/G/B MIN, MID2,MID1 is 192, 448,
704.
R/G/B MIN = 192
R/G/B MID2 = 448
R/G/B MID1 = 704
L Coefficient(RL1H~BL3L)
O
--> Calculation method (L1)
L1 coefficient = 1 / (brightness level(MID2) - brightness level(MIN)
L1coeff = 1 / (448-192) = 1 / 256 = 0.00390625
L1coeff(hex) = hex(0.00390625 x 2
--> L1H(high 9bit) = b'000000010 L1L(low 9bit) = b'000000000
- calcuate L2, L3 same with L1
L2 coefficient = 1 / (brightness level(MID1) - brightness level(MID2)
L3 coefficient = 1 / (brightness level(MAX) - brightness level(MID1)
: case of 4 Brightness Level
17. GL1H : Upper 9bit of MID2 brightness correction coeffi-
cient in G MIN.
--- Change according to GMIN and GMID2 value.
18. GL1L : Lower 9bit of MID2 brightness correction coeffi-
cient in G MIN.
--- Change according to GMIN and GMID2 value.
19. GL2H : Upper 9bit of MID1 brightness correction coeffi-
cient in G MID2.
--- Change according to GMID2 and GMID1 value.
20. GL2L : Lower 9bit of MID1 brightness correction coeffi-
cient in G MID2.
--- Change according to GMID2 and GMID1 value.
21. GL3H : Upper 9bit of MAX brightness correction coeffi-
cient in G MID1.
--- Change according to GMID1 and GMAX value.
(use it while adjusting 4 coefficient)
22. GL3L : Lower 9bit of MAX brightness correction coeffi-
cient in G MID1.
--- Change according to GMID1 and GMAX value.
(use it while adjusting 4 coefficient)
23. BL1H : Upper 9bit of MID2 brightness correction coeffi-
cient in B MIN.
--- Change according to BMIN and BMID2 value.
24. BL1L : Lower 9bit of MID2 brightness correction coeffi-
cient in B MIN.
--- Change according to BMIN and BMID2 value.
25. BL2H : Upper 9bit of MID1 brightness correction coeffi-
cient in B MID2.
--- Change according to BMID2 and BMID1 value.
26. BL2L : Lower 9bit of MID1 brightness correction coeffi-
cient in B MID2.
--- Change according to BMID2 and BMID1 value.
27. BL3H : Upper 9bit of MAX brightness correction coeffi-
cient in B MID1.
--- Change according to BMID1 and BMAX value.
(use it while adjusting 4 coefficient)
28. BL3L : Lower 9bit of MAX brightness correction coefficient
in B MID1.
--- Change according to BMID1 and BMAX value.
(use it while adjusting 4 coefficient)
18 ) = 0 x 0400
29. RLMIN : Setting up the MINIUM Level of R --- Set under
200
30. RLMID2 : Setting up the MIDDLE 2nd Level of R ---
Middle level when 3coefficient
31. RLMID1 : Setting up the MIDDLE 1st Level of R --- Max
level when 3coefficient
32. RLMAX : Setting up the MAX Level of R
33. GLMIN : Setting up the MINIUM Level of G --- Set under
200
34. GLMID2 : Setting up the MIDDLE 2nd Level of G ---
Middle level when 3coefficient
35. GLMID1 : Setting up the MIDDLE 1st Level of G --- Max
level when 3coefficient
36. GLMAX : Setting up the MAX Level of G
37. BLMIN : Setting up the MINIUM Level of B --- Set under
200
38. BLMID2 : Setting up the MIDDLE 2nd Level of B ---
Middle level when 3coefficient
39. BLMID1 : Setting up the MIDDLE 1st Level of B --- Max
level when 3coefficient
40. BLMAX : Setting up the MAX Level of B
41. HVSCAN : Setting up the scan direction while adjusting
unifomity - Do not adjust
42. TestMode : uniformity adjustment test - Do not adjust
(4) Adjustment Sequence
1) Adjust the screen coordinates as shown below.
0 1 2 3 . . . . . . . . . . . . x x . . . . . . . . . . 1 5 1 6
1
.
y y
.
11
1 2
(Fig. 5) Screen divisio diagram for uniformity adjustment
2) Output the VDP TEST PATTERN signal correspond to the
Max value.
Read the white coordinates and communicate 3 line with
ET7050 IC through measurement equipment of optics.
Adjust screen coordinates data to adjust the color unifor-
mity of max point.
At this time, make sure that deviation is +5~-5% and stan-
dard is color coordinate of center.
3) Output the VDP TEST PATTERN signal correspond to the
MID value.
Read the white coordinates and communicate 3 line with
ET7050 IC through measurement equipment of optics.
Adjust screen coordinates data to adjust the color unifor-
mity of mid point.
At this time, make sure that deviation is +5~-5% and stan-
dard is color coordinate of center.
4) Output the VDP TEST PATTERN signal correspond to the
MIN value.
Read the white coordinate and communicate with ET7050
IC through measurement equipment of optics.
Adjust screen coordinates data to adjust the color unifor-
mity of miner point.
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