Screen uniformity test
Flat gray fields reveal what black screens hide: blotches, tint shifts, and the dirty screen effect. Step through 50%, 25%, and 75% gray plus white, and look for uneven patches. Click or press → to change fields, Esc to exit.
Screen uniformity FAQ
- What is screen uniformity?
- How evenly a display reproduces a single flat color across its whole surface. On a perfectly uniform panel, a 50% gray field looks identical in the center, corners, and edges — no darker patches, no warm or cool tinted zones, no vertical banding.
- What is the dirty screen effect?
- Blotchy, smudge-like darker areas most visible on flat mid-gray fields and during panning shots in sports — as if the screen needs cleaning when it doesn't. It comes from uneven backlighting or panel manufacturing variance, and mid-grays (around 50%) reveal it far better than black or white screens.
- How much non-uniformity is acceptable?
- Every panel shows some — larger panels more so. Slight edge darkening on a gray field that you never notice in real content is normal. Distinct blotches visible during everyday video, or a strong color tint difference between screen halves, is worth a warranty claim.