How to Check Screen Uniformity
Use white, gray and color screens to check brightness uniformity, tint, dirty screen effect and panel consistency.
Quick answer
Check screen uniformity with white, light gray and mid-gray fullscreen fields at your normal brightness and viewing position. Look for fixed tint, darker bands, cloudy patches and dirty screen effect, then confirm whether they remain visible in everyday content.
Last reviewed: August 1, 2026 · Testing method and editorial policy
Use more than one gray level
White reveals tint and dark spots, while mid-gray often makes dirty screen effect, vertical bands and uneven brightness easier to see.
Control viewing conditions
Judge the panel from the distance and angle you normally use. LCD viewing-angle shifts and local dimming can look like uniformity defects during unrealistic testing.
Measure practical impact
A variation visible only on a synthetic field may be tolerable. A fixed patch that appears in documents, sports pans or normal video is more relevant to a return decision.
How to verify it
- Clean the panel and set normal brightness.
- Inspect white, light gray and mid-gray fields fullscreen.
- Compare the same areas on real documents, video and slow camera pans.
- Record the color, brightness and location of repeatable problems.