Find stuck pixels, dead pixels and uniformity defects.
Permanent black dot
A pixel whose 3 subpixels are off. Mostly visible on a white background.
Fixed colored dot
One or two subpixels stay lit (often red, green or blue), visible on a dark background.
White dot on black
All subpixels stay fully lit, especially visible on a pure black background.
Before you start:
Clean your screen carefully with a microfiber cloth. A speck of dust is easily mistaken for a dead pixel.
8 test colors included: