Acer AM501 AM501 Monitor Service Guide - Page 29

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. 25