Screen Uniformity Test for OLED Banding and DSE
Reveal vertical banding, dirty screen effect, mura, tint shifts, and uneven brightness with a precisely adjustable full-screen gray field. Start near black, then compare mid-gray and white.
Start at 5% gray
Adjust the field from 1% near-black to 100% white while staying in full screen.
What this screen test can reveal
Vertical banding
Dark or bright vertical columns are often most visible between 2% and 10% gray on OLED panels.
Dirty screen effect
Patchy areas that resemble faint dirt can become distracting during sports, games, and camera pans.
Mura and blotching
Irregular cloudy regions or pixel-level luminance variation may indicate panel non-uniformity.
Tint and brightness variation
Mid-gray and white fields reveal pink, green, or yellow tint as well as edge-to-center brightness differences.
How to run an accurate test
- 1
Use a dim, reflection-free room
Remove reflections but avoid total darkness when checking brighter gray fields.
- 2
Begin at 5% gray
Inspect the full screen from your normal seating position before moving closer.
- 3
Sweep through the range
Compare 1%, 2%, 10%, 20%, 50%, and 100%. Record which issues remain visible at multiple levels.
- 4
Confirm with real content
A test pattern can exaggerate faint variation. Give priority to defects visible in normal viewing and camera pans.
Frequently asked questions
Why is 5% gray used for OLED uniformity tests?
Near-black gray makes small differences in OLED pixel output easier to see. Vertical banding, mura, and uneven compensation that disappear on bright content can become visible around 2% to 10% gray.
What is dirty screen effect?
Dirty screen effect is visible non-uniformity that can resemble faint smudges, bands, or darker patches during camera pans and sports. It is most meaningful when it remains visible from a normal viewing position during real content.
Is some OLED banding normal?
Very faint near-black variation can occur on OLED panels, especially when new. Severe bands that remain visible in normal dark scenes are more concerning. Run the panel's recommended compensation cycle before making a warranty decision.
Can a browser measure uniformity numerically?
No. This page provides controlled visual fields. Numerical luminance and color uniformity measurements require a meter and readings at multiple points across the screen.