Defective pixel

[2] Similar defects can also occur in charge-coupled device (CCD) and CMOS image sensors in digital cameras.

In that state, the liquid crystal material does not do any rotation so that the light from the backlight does not pass through the RGB layer of the display.

If an LCD is subjected to physical shock, this could cause one or more TAB connections to fail inside the display.

Hardware manufacturers and distributors claim that TAB faults, as opposed to other physical defects found in an LCD, do not allow for repair.

Some manufacturers have a zero-tolerance policy with regard to LCD screens, rejecting all units found to have any number of (sub-)pixel defects.

[1] Some screens come with a leaflet stating how many dead pixels they are allowed to have before the owner can send them back to the manufacturer.

Close-up of an LCD, showing a dead green subpixel as a black rectangle
A photograph taken with a damaged image sensor
Dark dot defect in a phone screen
Defective pixels on LCD monitor
A flip-disc variable-message sign with clock, showing several stuck pixels.
Hundreds of hot pixels appear in a 32-minute long exposure photograph taken in virtual darkness. Note: Must be viewed at full size.