Advantech IDK-1115WP-45FHA2 User Manual page 33

Figure A.4 Response Time Definition
Note! Definition of Contrast Ratio (CR): The contrast ratio can be calculated
by the following expression.
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
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