Philips 170C8FS/00, Service Manual

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Philips' Flat Panel Monitors Pixel Defect Policy
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 sub pixel 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 for
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 sub pixels on a 17"
XGA monitor may be defective. Furthermore, Philips sets even higher quality
standards for certain types or combinations of pixel defects that are more
noticeable than others. This policy is valid worldwide
Philips Pixel Defect Policy
Pixels and Sub pixels
A pixel, or picture element, is composed of three sub pixels
in the primary colors of red, green and blue. Many pixels
together form an image. When all sub pixels of a pixel are lit,
the three colored sub pixels together appear as a single white
pixel. When all are dark, the three colored sub pixels together
appear as a single black pixel. Other combinations of lit and
dark sub pixels appear as single pixels of other colors.
Types of Pixel Defects
Pixel and sub pixel defects appear on the screen in different ways.
There are two categories of pixel defects and several types of sub
pixel defects within each category.
Bright Dot Defects Bright dot
defects appear as pixels or sub pixels that are always lit or 'on'.
That is,a
bright dot is a sub-pixel that stands out on the screen
when the monitor displays a dark pattern.There are the types
of bright dot defects
Black Dot Defects Black dot defects appear as pixels or sub
pixels that are always dark or 'off'. That is, a dark dot is a
sub-pixel that stands out on the screen when the monitor
displays a light pattern.These are the types of black dot defects:
Proximity of Pixel Defects
Because pixel and sub pixels defects of the same type that
are near to one another may be more noticeable, Philips also
specifies tolerances for the proximity of pixel defects.
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 sub pixel defects exceeding the
tolerances listed in the following tables.
BRIGHT DOT DEFECTS ACCEPTABLE LEVEL
MODEL 170C7 190C7
1 lit subpixel 3 or fewer 3 or fewer
2 adjacent lit subpixels 1 or fewer 1 or fewer
3 adjacent lit subpixels (one
white pixel)
0 0
Distance between two bright
dot defects*
15 mm or more 25 mm or more
Total bright dot defects of all
types
3 or fewer 3 or fewer
BLACK DOT DEFECTS ACCEPTABLE LEVEL
MODEL 170C7 190C7
1 dark subpixel 4 or fewer 5 or fewer
2 adjacent dark subpixels 2 or fewer 2 or fewer
3 adjacent dark subpixels 0 0
Distance between two black
dot defects*
15 mm or more 15 mm or more
Total black dot defects of all
types
4 or fewer 5 or fewer
BLACK DOT DEFECTS ACCEPTABLE LEVEL
MODEL 170C7 190C7
Total bright or black dot
defects of all types
5 or fewer 5 or fewer
Note:
* 1 or 2 adjacent sub pixel defects = 1 dot defect
All Philips monitors are ISO13406-2 Compliant
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