200VW8 LCD

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Set contrast at 100% and turn the brightness to get average above 300 nits at centre of the screen. Apply the Fig 1, it should comply with the following formula:

B_min

X 100%>75%

B_max

Where B_max = Maximum brightness

B_min = Minimum brightness

8.10White Uniformity

Definition of White Variation (δW):

Measure the luminance of gray level 255 at 9 points

δW = Maximum [L(1), L(2) …… L(9)] / Minimum [L(1), L(2) …… L(9)]

90%

50%

10%

1

2

3

4

5

6

7

8

9

10%

50%

90%

Spec : =< 1.33 (In all ranges)

8.11Contrast 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

8.12White color adjustment

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:

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Philips 200VW8FB service manual White Uniformity, Contrast ratio, White color adjustment