11
150B LCD
Definition of Pixel Defects
0. General
Philips strives to deliver the highest quality products. We use
some of the industry's most advanced manufacturing processes
and practice stringent quality control. However, pixel or subpixel
defects on the TFT LCD panels used in flat panel monitors are
sometimes unavoidable. No manufacturer can guarantee that all
panels will be free from pixel defects, but Philips guarantees that
any monitor with an unacceptable number of defects will be
repaired or replaced under warranty. This notice explains the
different types of pixel defects and defines acceptable defect
levels of each type. In order to qualify for repair or replacement
under warranty, the number of pixel defects on a TFT LCD panel
must exceed these acceptable levels. For example, no more than
0.0004% of the subpixels on a 15" XGA monitor may be defective.
Additionally, because some types or combinations of pixel defects
are more noticeable than others, Philips sets even higher quality
standards for those.
1. Pixels and Subpixels
A pixel, or picture element , is composed of three subpixels in the
primary colors of red, green and blue. Many pixels together form
an image. When all subpixels of a pixel are lit, the three colored
subpixels together appear as a single white pixel. When all are
dark, the three colored subpixels together appear as a single
black pixel. Other combinations of lit and dark subpixels appear
as single pixels of other colors.
2. Types of Pixel Defects
Pixel and subpixel defects appear on the screen in different ways.
There are two categories of pixel defects and several types of
subpixel defects within each category.
Bright dot defects appear as pixels or subpixels that are always lit
or "on". These are the types of bright dot defects:.
Bright dot defects
One lit red, green or blue subpixel
Two adjacent lit subpixels:
- Red + Blue = Purple
- Red + Green = Yellow
- Green + Blue = Cyan (Light Blue)
Three adjacent lit subpixels
(One white pixel)
Black dot defects
Black dot defects appear as pixels or subpixels that are always
dark or "off". These are the types of black dot defects:
One dark subpixel
Two or three adjacent dark subpixels
3. Pixel Defect Tolerances
In order to qualify for repair or replacement due to pixel defects
during the warranty period, a TFT LCD panel in a PHILIPS flat
panel monitor must have pixel or subpixel defects exceeding the
tolerances listed in the following tables.
Bright Dot Defects
Acceptable Level
Model
1 lit subpixel
10 or fewer
10 or fewer
6 or fewer
10 or fewer
2 adjacent lit subpixels
3 or fewer
3 or fewer
2 or fewer
3 or fewer
3 adjacent lit subpixels
None
None
None
None
(one white pixel)
Distance between two
12 mm or more 12 mm or more 14 mm or more 14 mm or more
bright dot defects*
Bright dot defects within
6 or fewer
6 or fewer
4 or fewer
4 of fewer
20mm circle
Total bright dot defects
10 or fewer
10 or fewer
6 or fewer
10 or fewer
of all types
140S, 140X
150B
151AX & 150P
181AS
Black Dot Defects
Acceptable Level
Model
1 dark subpixel
10 or fewer
10 or fewer
6 or fewer
10 or fewer
2 adjacent dark subpixels
3 or fewer
3 or fewer
1 or fewer
2 or fewer
3 adjacent dark subpixels
None
None
None
1 or fewer
Distance between two
4 mm or more 4 mm or more 4 mm or more 14mm or more
black dot defects*
Black dot defects within
6 or fewer
6 or fewer
4 or fewer
5 of fewer
20mm circle*
Total black dot defects
10 or fewer
10 or fewer
6 or fewer
15 or fewer
of all types
140S, 140X
150B
151AX & 150P
181AS
Black Dot Defects
Acceptable Level
Model
Total bright or black dot
12 or fewer
12 or fewer
10 or fewer
15 or fewer
defects of all types
140S, 140X
150B
151AX & 150P
181AS
Note: 1 or 2 adjacent subpixel defects = 1 dot defect
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