This test displays stepped grayscale backgrounds to help identify backlight bleeding, edge darkening (vignetting), and Dirty Screen Effect (DSE).
Screen Tester does not calculate a synthetic "uniformity percentage" or use webcam exposure measurements. Webcams and phone cameras suffer from severe lens vignetting, sensor gain artifacts, and automatic ISO compensation that misrepresent true screen luminance. Reliable Delta E or luminance uniformity profiling requires laboratory spot-photometer or colorimeter grid measurements.
Detect IPS glow, clouding, and light leakage from the bezel in a dark room environment.
Fill your screen with pure primary, secondary, black, and white fields to inspect overall panel cleanliness.
Evaluate subtle dark-tone separation, black crush, and near-black gradation above true black.
