Acer HS244HQ, Lifecycle Extension Manual

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1.5 Optical Characteristics:
1.5.1 Brightness uniformity:
The uniformity is determined by using a photometer to measure the 9 points luminance in front of monitor
after at least 30 minutes warm up. It sha ll be test at 1920x1080/60Hz mode and full white square pattern with
contrast / brightness in default value. The values specified are at an approximate distan ce 50 cm from the
LCD surface and at 0 viewing angle.
The 9 test points are defined as below:
st
1.5.2 Contrast ratio (CR):
1.5.2.1 General CR:
The contrast ratio is determined by using a photometer to measure the maximum and minimum
luminance in front of monitor after at least 30 minutes warm up. It shall be test at
1366x768/60Hz mode and full white/full black square pattern with contrast/brightness in default
value. The values specified are at an approximate distance 50cm from the LCD surface and at 0
viewing angle. The contrast ratio is calculated as below:
Surface luminance with all white pixels
Contrast ratio (CR) = -----------------------------------------------------------------
Surface luminance with all black pixels
1.5.2.2 ACM (Auto Contrast Management):
The input image signal source may be various levels of illumination, and this ACM unit can analyze it
as histogram for the various levels of illumination, according to the analyzed result, when input a low-
luminance level image, display brightness will be adopted to corresponding low level, so that enhance
the contrast rate, this facilitates visual ergonomics enhancement .The monitor should me CR
>10000000:1 when ACM function is active.
1.5.3 Response time: