TFT Dead Pixel Check

TFT Monitors are made up of many pixels. Each Pixel has 3 sub-pixels, red, green and blue. Each sub-pixel has its own transistor. A typical 1920 x 1200 monitor will have 2,304,000 pixels and (multiply by 3), 6,912,000 transistors. As there are so many transistors, producing a TFT Monitor is a highly complex process, and as a result defects can occur.

These defects result in dead pixels, stuck pixels, bruises and poor refresh rates. They are not repairable.

To regulate the acceptability of defects and to protect the end user, ISO have created a standard for manufacturers to follow. ISO-13406-2 recommends how many pixel faults are acceptable before a panel can be replaced. ISO 13406-2 recommends how many defaults are acceptable in a display before it should be replaced, within the terms & conditions of warranty. Class II is the common class for consumer equipment. Class I is for Military, Hospital or other Critical applications.

All monitors sold by UK Gaming Computers adhere to the ISO 13406-2 Spec in Class II requirements as standard.

The table below shows the allowable number of malfunctioning pixels that are acceptable, depending on the native resolution of the LCD and allowing for 2 malfunctioning pixels per million pixels.

Native resolution No. of pixels No. of million pixels Acceptable defects
1024 x 768 786,432 0.8 2
1280 x 1024 1,310,720 1.3 3
1600 x 1200 1,920,200 1.9 4
2048 x 1536 3,145,728 3.1 6


The table below shows the allowable number of malfunctioning sub-pixels that are acceptable, depending on the native resolution of the LCD and allowing for 5 malfunctioning sub-pixels per million pixels.

Native resolution No. of pixels No. of million pixels Acceptable defects
1024 x768 786,432  0.8 4
1280 x 1024 1,310,720 1.3 7
1600 x 1200 1,920,200 1.9 10
2048 x 1536 3,145,728 3.1 16


The table below shows the allowable number of malfunctioning sub-pixels that are acceptable within a 5 x 5 block of pixels, depending on the native resolution and allowing for 2 malfunctioning sub-pixels within a 5 x 5 block, per million pixels.

Native resolution No. of pixels No. of million pixels Acceptable defects
1024 x 768 786,432 0.8 2
1280 x 1024 1,310,720 1.3 3
1600 x 1200 1,920,200 1.9 4
2048 x 1536 3,145,728 3.1 6


The above is relevant to Class II LCD panels.