Philips Pixel Defect Policy - Philips BDL6531E/00 Service Manual

PIXEL DEFECT POLICY
We strive to deliver the highest quality products and use some of the
industry's most advanced manufacturing processes whilst practicing
stringent quality control. However, pixel or sub-pixel defects on the PDP /
TFT panels used in Plasma- & LCD- displays are sometimes unavoidable.
No manufacturer can guarantee that all panels will be free from pixel defects,
but Philips guarantees that any Plasma- & LCD- displays with an
unacceptable number of defects will be repaired during the warranty period
in line with your local guarantee conditions. This notice explains the different
types of pixel defects and defines the acceptable defect level for the
BDL4230E LCD screen. In order to qualify for repair under warranty, the
number of pixel defects must exceed a certain level as shown in the
reference table. If the LCD screen is within specification a warranty
exchange / claim back will be refused. Additionally, because some types or
combinations of pixel defects are more noticeable than others, Philips sets
even higher quality standards for those.
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 + Dot Definition
Pixel and sub-pixel defects appear on the screen in different ways. There are
three categories of pixel defects and several types of sub-pixel defects within
each category..
Dot definition = What is a defective "Dot"?
One or more defective, adjacent sub-pixel is defined as one "dot". The
number of defective sub-pixels is not relevant to define a defective dot. This
means that a defective dot can consist of one, two or three defective
sub-pixels which can be dark or lit.
Bright Dot Defects
Bright dot defects appear as pixels or sub-pixels that are always lit or "on".
These are the examples of bright dot defects:
Two adjacent lit
sub-pixels:
One lit red, green or - Red + Blue = Purple -
blue sub-pixel Red + Green = Yellow
- Green + Blue = Cyan
(Light Blue)

Philips Pixel Defect Policy

.
Three adjacent lit
sub-pixels (one white
dot)
Dark Dot Defects
Black dot defects appear as pixels or sub-pixels that are always dark or "off".
These are the examples of black dot defects
One dark dot l Two adjacent dark
dots = 1 pair of dark
dots
Proximity of Pixel Defects
Because pixel and sub-pixels defects of the same type that are nearby one
another may be more noticeable, Philips also specifies tolerances for the
proximity of pixel defects. In the table below you can find specifications
about:
• Allowed amount of adjacent dark dots = (adjacent dark dots =1 pair of dark
dots)
• Minimum distance between dark dots
• Total no. of all defective dots
PIXEL DEFECT TOLERANCES
In order to qualify for repair due to pixel defects during the warranty period, a
PDP / TFT panel in a Philips Plasma / LCD display must have pixel or
sub-pixel defects exceeding the tolerances listed in the following table.
BRIGHT DOT EFFECT
Model
1 lit sub pixel
BLACK DOT EFFECT
1 dark sub pixel
TOTAL DOT DEFECTS OF ALL TYPES
Note: * 1 or 2 adjacent sub pixel defects = 1 dot defect
BDL6531E LCD 15
Two dark dots,
specifications defines
the minimum distance
between dark dots
ACCEPTABLE LEVEL
BDL6531E
1
ACCEPTABLE LEVEL
10
10