Acer AM501, Service Manual

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4.14 White Balance
Set the external BRIGHTNESS at the point that raster just cut off, adjust CONTRAST over the range
from 5F-L to 20F-L, or reversed, with full-intensity reverse pattern, the color coordinate, measured by
MINOLTA TV-COLOR ANALYZER-II (TV-2130), shall be within the limitation listed below:
x=0.281 0.03
y=0.311 0.03
(At 5 F-L and 20 F-L)
4.15 Luminance Uniformity
The variation in average display luminance between any area(with dimension approximate 2 cm of
diameter)on standard flat white screen, must be less than 35% of the luminance of the brightest area
with brightness control at cut-off and contrast control adjusted to 80 nits of luminance on the center of
screen.
4.16 Focus
When external contrast control is adjusted for 15+/-1FL light output with a flat white field pattern, then
switch to a character pattern filled with "H" characters, the characters shall be readable and disting
uishable.
4.17 Image Stability (Jitter)
Not perceivable Jitter will be present on the display, when displaying a cross-hatch pattern, at a distance
of 500 mm from the screen. In any case it is not admitted a measured Jitter value greater than one dot
(both on X axis or on Y axis).
4.18 Warm-Up Time
The warm-up time shall be 20 minutes maximum. At the end of the warm-up period, no adjustment or
service shall be necessary to cause the display to meet the requirements contained herein. After a
warm-up time of 1 minute, the display shall produce a usable image. Repetitive power ON/OFF cycles
must be possible with a minimum switch-off time of about 4s.