Akai LCT42Z6TM, Service Manual

Page: 71 / 78

Appendix B
: Black Level and Black Uniformity
A : H / 4 mm
B : V / 4 mm
H : 697.685
mm
V : 392.256 mm
@ H,V : Active Area
H
A
V
B
①
③ ②
⑤
④
It is not available to be specified black level and black uniformity on the spec at this moment. So LPL will get
more actual data for the future production(LC420WU1-SL01).
1. Black Level :
Surface Luminance of Black (L
BLACK
) is the luminance value at center 1-point.
2. Black Uniformity
The variation of surface luminance of black ,
δ
BLACK
is defined as :
δ
BLACK = Maximum(L
on1
,L
on2
, L
on3
, L
on4
, L
on5
) / Minimum(L
on1
,L
on2
, L
on3
, L
on4
, L
on5
)
3. Sampling Size : regular RV event test quantity ( 5 pcs )
4. Measurement Method : Follow same rule as optical characteristics measurement.
5. Measurement location: refer to below.
6. Current Status
Below is actual data of production on RV (4 Jul 2005 ~ 5 Jul 2005 ). This is only useful for reference.
1) light leakage & Stitch limit sample : # 177
2) Touch limit sample : #148
No. Luminance Black Level
1 639
606
623
619
647
2
0.75
0.76
0.78
0.75
3
4
5 0.78
7. Plan to review Black Level and Black Uniformity
LPL will continue to monitor the black level and uniformity. Both LPL and Philips will review black level
as well as black uniformity together. This spec will be discussed sooner or later. ( end of Sept.)
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Ver. 1.0 July. 21, 2005