PHILIPS 170W4P74
Service Manual

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 subpixel 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 subpixels on a 15" XGA monitor may be defective. Additionally, because some types or combinations of pixel defects are more noticeable than others, Philips sets even higher quality standards for those. Black Dot Defects

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Black dot defects appear as pixels or subpixels that are always dark or "off". These are the types of black dot defects:

One dark subpixel

Two or three adjacent dark subpixels Proximity of Pixel Defects Because pixel and subpixels defects of the same type that are nearby 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 subpixel defects exceeding the tolerances listed in the following tables. BRIGHT DOT DEFECTS MODEL 1 lit subpixel 2 adjacent lit subpixels 3 adjacent lit subpixels (one white pixel) Distance between two bright dot defects* Bright dot defects within 20 mm circle Total bright dot defects of all types ACCEPTABLE LEVEL 170W4 3 or fewer 1 or fewer 0 15 mm or more 3 or fewer

Pixels and Subpixels A pixel, or picture element, is composed of three subpixels in the primary colors of red, green and blue. Many pixels together form an image. When all subpixels of a pixel are lit, the three colored subpixels together appear as a single white pixel. When all are dark, the three colored subpixels together appear as a single black pixel. Other combinations of lit and dark subpixels appear as single pixels of other colors. Types of Pixel Defects Pixel and subpixel defects appear on the screen in different ways. There are two categories of pixel defects and several types of subpixel defects within each category. Bright Dot Defects Bright dot defects appear as pixels or subpixels that are always lit or "on". These are the types of bright dot defects:

BLACK DOT DEFECTS One lit red, green or blue subpixel MODEL 1 dark subpixel 2 adjacent dark subpixels 3 adjacent dark subpixels Distance between two black dot defects* Two adjacent lit subpixels: - Red + Blue = Purple - Red + Green = Yellow - Green + Blue = Cyan (Light Blue) Black dot defects within 20 mm circle* Total black dot defects of all types

ACCEPTABLE LEVEL 170W4 4 or fewer 2 or fewer 1 or fewer 15 mm or more 4 or fewer

TOTAL DOT DEFECTS MODEL

ACCEPTABLE LEVEL 170W4

Total bright or black dot defects of all types 4 or fewer

Three adjacent lit subpixels

Note: 1 or 2 adjacent subpixel defects = 1 dot defect