Acer M190E5-L0A, Service Manual

Page: 11 / 38

11
(2) Definition of Contrast Ratio (CR):
The contrast ratio can be calculated by the following expression and figure below.
Contrast Ratio (CR) = L255 / L0
L255: Luminance of gray level 255
L 0: Luminance of gray level 0
CR = CR (5)
CR (X) is corresponding to the Contrast Ratio of the point X at Figure in Note (5).
Definition of luminance measured points and Brightness Uniformity:
Delta X=17.0mm;Delta Y=17.0mm
。
Luminance of center point: L=L (1)
Brightness Uniformity Measurement points: Five specified points 1-5
Formula: Maximum [L (1), L (2), L (3), L (4), L (5), L (6), L (7), L (8), L (9), L (10),
L (11), L (12), L (13)]/Minimum [L (1), L (2), L (3), L (4), L (5),
L (6), L (7), L (8), L (9), L (10), L (11), L (12), L (13)]
Active area
Vertical Line
N
umber [pixel]
Horizontal Line Number [pixel]
X
: Test point