Akai LCT2765TD, Service Manual

Page: 92 / 105

Preliminary
Note (4) Definition of Luminance of White (L
C
, L
AVE
):
Measure the luminance of gray level 255 at center point and 5 points
L
C
= L (5)
L
AVE
= [L (1)+ L (2)+ L (3)+ L (4)+ L (5)] / 5
L (x) is corresponding to the luminance of the point X at the figure in Note (7).
Note (5) Definition of Cross Talk (CT):
CT = | Y
B
– Y
A
| / Y
A
× 100 (%)
Where:
Y
A
= Luminance of measured location without gray level 0 pattern (cd/m
2
)
Y
B
= Luminance of measured location with gray level 0 pattern (cd/m
2
)
Gray 128
(D,W)
(0, 0)
Y
A, L
(D/8,W/2)
Y
A, D
(D/2,7W/8)
Y
A, R
(7D/8,W/2)
Y
A, U
(D/2,W/8)
Active Area
Active Area
Gray 0
Gray 0
(D/4,W/4)
(3D/4,3W/4)
(0, 0)
Y
B, U
(D/2,W/8)
Y
B, R
(7D/8,W/2)
Y
B, D
(D/2,7W/8)
Y
B, L
(D/8,W/2)
Gray 128
(D,W)
Note (6) Measurement Setup:
The LCD module should be stabilized at given temperature for 1 hour to avoid abrupt temperature
change during measuring. In order to stabilize the luminance, the measurement should be
executed after lighting Backlight for 1 hour in a windless room.
LCD Module
LCD Panel
Light Shield Room
(Ambient Luminance < 2 lux)
Display Color Analyzer
(Minolta CA210)
Center of the Screen
９１ˋ