Advantech IDK-1110P-50XGB1 User Manual page 36

Note (5) Measurement Setup:
The LCD module should be stabilized at given temperature to avoid
abrupt temperature change during measuring. In order to stabilize the
luminance, the measurement should be executed after lighting back
light for 40 minutes in a windless room. The measurement placement of
module should be in accordance with module drawing.
Note (6) Definition of White Variation (
Measure the luminance of White at 5 points.
Luminance of White: L(X), where X is from 1 to 5.
IDK-1110P-50XGB1 User Manual
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