Procedure:

A. Black Level Adjustment: (DLP brightness)

1.

Change pattern of pattern generator :

 

 

 

 

Pattern : Black (Gray 0)

2.

Adjust DLP Brightness to let the black picture to just distinguish.

B. White Level Adjustment: (AD contrast---R,G,B gain)

1.Change pattern of pattern generator : pattern : White (100% Gray)

2.Use Lux meter to measure the white level. Adjust the contrast value of AD9883 (RGB) to let the light output to just max.

3.Change to 32-gray (0 ~ 100%) pattern. All steps must appear,

C. Offset adjustment at low brightness (AD R, G, B offset)

1.Change Timing and pattern of pattern generator : pattern : 10% Gray

2.Set user color temp to 6500K.

3.Adjust AD9883 Red and Blue Offset to meet 6500K color spec.

D. Color Temperature at high brightness (Scalar Gamma R, G, B Gain)

1. Change Timing and pattern of pattern generator :

Timing : 800x600@60Hz (H:37.879Khz,V:60.317Hz) Pattern : 80% gray

2 Color temperature spec: CIE 1976 u’, v’ chromaticity)

Color temperature

5400°K

6500°K

7500°K

x =

 

 

 

 

27u'

0.333

0.312

0.296

18u' − 48v' + 36

 

 

 

 

 

y =

 

 

 

12v'

0.333

0.329

0.316

 

 

 

 

 

 

 

18u' − 48v' + 36

 

 

 

u ' =

 

 

4x

 

0.210

0.197

0.190

 

− 2x + 12 y + 3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

v ' =

 

 

9 y

 

0.473

0.468

0.459

 

− 2x + 12 y + 3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Deviation:

<=0.010

<=0.010

<=0.010

u’v’=

( ∆u' 2 + ∆v' 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Color Temp 4 = color temp is the same as that of 6500K

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BenQ PE8700 service manual Procedure Black Level Adjustment DLP brightness, White Level Adjustment AD contrast---R,G,B gain