15
3.3 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 18.5" 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 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:
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)
