Philips 240B4 User Manual page 36

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 Monitor panels
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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
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acceptable defect levels for each type. In order
to qualify for repair or replacement under
warranty, the number of pixel defects on a TFT
Monitor panel must exceed these acceptable
levels. For example, no more than 0.0004% of
the sub pixels on a 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.
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.
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'. 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.
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).
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