Philips BDL4220QL user manual Pixel Defect Policy, Pixels and Sub-pixels, Bright Dot Defects

BDL4220QL

7.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 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.

7.1.Pixels and Sub-pixels

subpixel

pixel

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.

7.2.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 are defined as one “dot”.The no. of defective sub-pixels are 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.

R G B

One dot = One Pixel; consists of three sub-pixels of Red, Green, and Blue.

7.3.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:

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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