12 13
4.5 Pixel Defect Tolerances
In order to qualify for repair due to pixel defects during the warranty period, a PDP / TFT panel in a Plasma / LCD- display must
have pixel or sub-pixel defects exceeding the tolerances listed in the following table.
BRIGHT DOT EFFECT ACCEPTABLE LEVEL
1 lit sub pixel 2
BLACK DOT EFFECT ACCEPTABLE LEVEL
1 dark sub pixel 10
TOTAL DOT DEFECTS 12
4.6 MURA
Dark spots or patches may occasionally appear on some liquid crystal display (LCD) panels. This is known within the industry
as Mura, which is a Japanese term for “unevenness.” It is used to describe an irregular pattern or area in which uneven screen
uniformity appears under certain conditions. Mura is a result of the deterioration of the liquid crystal alignment layer and is most
commonly caused by long-term operation under high ambient temperatures. It is an industry- wide phenomenon and Mura is
not repairable. It is also not covered by our warranty terms. Mura has been around since the introduction of LCD technology and
with screens getting bigger and in operation 24/7, many displays are running in low light conditions. This all adds to the possibility
of Mura affecting displays.
4.3 Dark Dot Defects
Black dot defects appear as pixels or sub-pixels that are always dark or “off.” These are the examples of black dot defects:
One dark dot Two adjacent dark dots =
1 pair of dark dots
Two dark dots,
specifcations defnes the
minimum distance
between dark dots
4.4 Proximity of Pixel Defects
Because pixel and sub-pixels defects of the same type that are nearby one another may be more noticeable, specifies tolerances
for the proximity of pixel defects. In the table below you can find specifications about:
• Allowed amount of adjacent dark dots = (adjacent dark dots = 1 pair of dark dots)
• Minimum distance between dark dots
• Total number of all defective dots
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