White Balance Adjustment - Sharp LC-37AD5E Service Manual

LC-37AD5E

[8] White Balance Adjustment

Adjustment gradation values (IN) appear on page 7/11 of process adjustment, and adjustment initial values (offset value) appear on pages 8/11 and
9/11. For white balance adjustment, adjust the offset values on pages 8/11 and 9/11.
[Condition of the unit for inspection] Modulated light: MAX (+8)
[Adjustment reference device] Minolta CA-210
[Adjustment]
Check that the values on page 7/11 of process adjustment are set as below. If not, change them accordingly.
M GAMMA IN 1 160
M GAMMA IN 3 480
M GAMMA IN 5 800
1) Display the current adjustment status at point 6. (Page 8/11 of process adjustment)
The display for checking the adjustment status is toggled by pressing the "6" button on the remote control.
(Normal OSD display → "6"→ display for check (OSD disappears) → "6" →normal OSD display → • • •)
2) Read the value of the luminance meter.
3) Change M GAMMA R6/M GAMMA B6 (Adjustment offset value) on page 9/11 of process adjustment so that the values of the luminance meter
approach x = 0.272 and y = 0.277.
(Basically, G is not changed. If adjustment fails with R and B, change G. When G is lowered, the weaker of R and B must be fixed.)
4) If G is changed in step 3), change the values of M GAMMA G1-M GAMMA G5 on pages 8/11 and 9/11 of process adjustment as follows. When not
changed, go to step5).
Offset value of M GAMMA G1 = (Offset value of M GAMMA G6) * (160/960)
Offset value of M GAMMA G2 = (Offset value of M GAMMA G6) * (320/960)
Offset value of M GAMMA G3 = (Offset value of M GAMMA G6) * (480/960)
Offset value of M GAMMA G4 = (Offset value of M GAMMA G6) * (640/960)
Offset value of M GAMMA G5 = (Offset value of M GAMMA G6) * (800/960)
5) Display the adjustment status of the current point 5. (Each time the "5" button on the remote control is pressed, the adjustment status check dis-
play is toggled.)
(Normal OSD display → "5" → Check display (OSD disappears) → "5" → Normal OSD display → • • •)
Change M GAMMA R5/M GAMMA B5 (adjustment offset value) on page 9/11 of process adjustment so that the values of the luminance meter
approach x = 0.272 and y = 0.277.
6) Repeat step 5) for points 4, 3, 2, and 1.
[Adjustment reference standard value]
±0.004
Adjustment spec
±0.002
Adjustment spec
M GAMMA IN 2 320
M GAMMA IN 4 640
M GAMMA IN 6 960
±0.006 (point 1)
Inspection spec
±0.004 (Excluding the above-mentioned)
Inspection spec
3 – 20