DEAD PIXEL

A 'dead pixel' is a defective pixel that remains unlit on an LCD screen or a CCD or CMOS sensor in a digital camera. The term "dead pixel" is often applied to other defective pixels, but there are also separate terms. A permanently lit (white) pixel is called a 'hot pixel', and a pixel that stays on a solid color (red, green, or blue) is known as a stuck pixel.

Contents

Manufacturer Policy

Manufacturers which offer a Zero-Dead-Pixel Warranty

See also

External links

Manufacturer Policy

In LCD manufacture, it is common for a display to be manufactured that has a number of sub-pixel defects (each pixel is composed of three primary-colored sub-pixels). The number of faulty pixels tolerated before a screen is rejected is dependent on the "class" which the manufacturer has given the display (although officially described by the ISO 13406-2 standard, not all manufacturers interpret this the same way, or follow it at all). Some manufacturers have a zero-tolerance policy with regard to LCD screens, rejecting all units found to have any number of sub-pixel or pixel defects, meaning the display is a "Class I" display. Others reject them according to the number of total defects, or the number of defects in a given group, or other definitions. Some screens come with a leaflet stating how many dead pixels they are allowed to have before you can send them back to the manufacturer. Dead pixels can also occur in clusters; these are particularly annoying, and in most cases these can be sent back to the manufacturer.
In some cases, the manufacturer sends all screens to sale, and then replaces the screen if the customer reports the unit as faulty and the dead pixels meet their minimum requirements for return.
The majority of dead pixels are only noticeable on a solid color background, for example through the use of the "Dead Pixel Checkers" which consist of 4 or 5 solid-color images.

Manufacturers which offer a Zero-Dead-Pixel Warranty

★ Philips (on their PerfectPanel(TM) range)

★ ViewEra (certain models. Covers any defective pixel within 6 months of purchase)

★ Toshiba (only high-end notebook models)

★ ASUS (Zero-Bright-Dot Policy on all but barebone laptops)

★ Nintendo (for the Nintendo DS)

★ Vizio (for most TVs check their site)

★ Samsung Australia

★ Viewsonic Policy

★ Sager Midern Computer
As of 2007, many LCD manufacturers do not offer such a warranty, and may refuse to fix or replace a monitor with dead pixels (e.g. multiple red pixels), sometimes even if the monitor arrives with the defect. Also, some policies vary from country to country. Customers should exercise scrutiny and search for a manufacturer's "pixel policy".

See also

★ Stuck pixel

External links

★ Laptop Showcase's Dead Pixel Buddy utility for testing for dead pixels

★ Tom's Hardware Guide investigates dead pixel policies

★ A look into dead pixels- 2007

★ A test for dead pixels

★ An animated gif that may fix dead pixel

★ Dead Pixel Locator