User Manual BDL4771V

6.3.BRIGHT DOT DEFECTS

Bright dot defects appear as pixels or sub-pixels that are always lit or "on". These are the examples of bright dot defects:

One lit red, green or blue sub-pixel

Two adjacent lit sub-pixels:

-Red + Blue = Purple

-Red + Green = Yellow

-Green + Blue = Cyan (Light Blue)

Three adjacent lit sub-pixels (one white dot)

6.4.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, specifications define the minimum distance between dark dots

6.5.PROXIMITY OF PIXEL DEFECTS

Because pixel and sub-pixels defects of the same type that are nearby one another may be more noticeable, Philips also 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 no. of all defective dots

6.6.PIXEL DEFECT TOLERANCES

In order to qualify for repair due to pixel defects during the warranty period, a PDP/TFT panel in a Philips LCD display must have pixel or sub-pixel defects exceeding the tolerances listed in the following table.

BRIGHT DOT EFFECT

ACCEPTABLE LEVEL

MODEL

BDL4771V

 

 

1 lit sub pixel

10

 

 

BLACK DOT EFFECT

ACCEPTABLE LEVEL

1 dark sub pixel

8

 

 

TOTAL DOT DEFECTS OF ALL TYPES

9

Note: * 1 or 2 adjacent sub pixel defects = 1 dot defect

 

6.7.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.

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Philips BDL4771V user manual Bright DOT Defects, Total DOT Defects of ALL Types