Philips 220SW8FB1/00, Руководство по обслуживанию

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10 220SW8 LCD
Philips Pixel Defect Policy
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 19" 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)
A red or blue bright dot must be more than 50 percent brighter than
neighboring dots while a green bright dot is 30 percent brighter than
neighboring dots.
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:
One dark sub pixel Two or three adjacent dark sub pixels
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 220SW8
1 lit subpixel 3
2 adjacent lit subpixels 1
3 adjacent lit subpixels (one white pixel) 0
Distance between two bright dot defects* >25mm
Total bright dot defects of all types 3
BLACK DOT DEFECTS ACCEPTABLE LEVEL
MODEL 220SW8
1 dark subpixel 5
2 adjacent dark subpixels 2
3 adjacent dark subpixels 0
Distance between two black dot defects* >15mm
Total black dot defects of all types 5
TOTAL DOT DEFECTS ACCEPTABLE LEVEL
MODEL 220SW8
Total bright or black dot defects of all types 5