Philips 231E1HSB, Service Manual

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231E LCD
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8.10 White Uniformity
Definition of White Variation (W):
Measure the luminance of gray level 255 at 9 points
W = Maximum [L(1), L(2) …… L(9)] / Minimum [L(1), L(2) …… L(9)]
90%
50%
10%
10%
1 2 3
4 5 6
7 8 9
50%
90%
Spec : =< 1.33 (In all ranges)
8.11 Contrast ratio
The contrast ration can be calculated by following expression.
Contrast Ratio (CR) = L255 / L0
L255 : Luminance of gray level 255
L0 : Luminance of gray level 0
Typical value: 1000:1
8.12 White color adjustment
(FW)
There are three factory preset white color 9300K, 6500K, sRGB.
Apply full gray 64 pattern, with brightness in 100 % position and the contrast control at 50 %
position. The 1931 CIE Chromaticity (color triangle) diagram (x,y) coordinate for the screen
center should be:
Product specification:
Mode Chromaticity Coordinate
OSD setting Temp. x y
Remark
0.313 ±0.020 0.329 ±0.020 For product Spec(DQA test)
0.313 ±0.015 0.329 ±0.015 For OQC Test:
Warm 6500K
0.313 ±0.005 0.329 ±0.005 For production alignment test
0.283 ±0.020 0.298±0.020 For product Spec(DQA test)
0.283 ±0.015 0.298±0.015 For OQC Test:
Cool 9300K
0.283 ±0.005 0.298±0.005 For production alignment test
User Panel White x Panel White y