Philips hudson iv 170x5, Service Manual

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Philips' Flat Panel Monitors Pixel D efect 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 15" 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.
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 D efects
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 appear as pixels or sub pixels that are always lit or
'on'. These are the types 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 pixel)
Black Dot Defects Black dot defects appear as pixels or sub
pixels that are always dark or 'off'. These are the types of black
dot defects:
One dark sub pixel Two or three adjacent dark sub pixels
Proximity of Pixel D efects
Because pixel and sub pixels defects of the same type that are
near to one another may be more
, Philips also
specifies tolerances for the proximity of pixel defects.
Pixel D efect 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.
Note:
* 1 or 2 adjacent sub pixel defects = 1 dot defect
All Philips monitors are ISO 1 3 406 -2 Compliant
Philips Pixel D efect Policy
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11
170X5 LCD
BRIGHT DOT DEFECTS ACCEPTABLE LEVEL
MODEL 170 X 5
1 lit subpixel
0
2 adjacent lit subpixels
0
3 adjacent lit subpixels (one white
pixel)
0
Distance between two bright dot
defects*
Total bright dot defects of all types
BLAC K DOT DEFECTS ACCEPTABLE LEVEL
MODEL
170 X 5
1 dark subpixel 4 or fewer
2 adjacent dark subpixels 1 or fewer
3 adjacent dark subpixels 0
Distance between two black dot defects* 15 mm or more
Total black dot defects of all types 4 or fewer
TOTAL DOT DEFECTS ACCEPTABLE LEVEL
MODEL 150 C 5
Total bright or black dot defects of all
types
5 or fewer
0
0