ScreenTestKit

Black Screen Test - Fullscreen Black Display

Open a fullscreen black screen test to check backlight bleed, bright or hot pixels, OLED image retention, edge light and dark-room uniformity.

Quick answer

A fullscreen black screen is useful for spotting hot pixels, stuck bright pixels, backlight bleed, edge glow and some OLED image retention marks.

Method: ScreenTestKit generates the test surface in your browser. Results depend on visual inspection; the site does not read or diagnose physical panel hardware.

How to use this test

  1. Use normal brightness first, then briefly compare a darker room if checking backlight bleed.
  2. Open the black screen fullscreen and let your eyes adjust for a few seconds.
  3. Scan the center, edges and corners for fixed bright dots or light patches.
  4. Follow up with white, gray or OLED tests if a mark remains visible.

What to watch for

  • Tiny bright dots that stay in the same physical location.
  • Light leaking from an edge or corner of an LCD panel.
  • Glow that changes strongly when you move your viewing angle.
  • Faint OLED marks from fixed logos, status bars or navigation UI.

How to interpret results

Bright dot

A fixed bright dot on black is more consistent with a stuck, hot or bright pixel than a dead black pixel.

Edge light

If light is visible during normal dark content, run the backlight bleed test and document brightness settings.

Camera looks worse

Phone photos often exaggerate black-screen glow, so judge normal-use visibility with your eyes.

Frequently asked questions

Should I test in a completely dark room?

Use normal lighting first. A dark room helps reveal bleed, but it can also make minor glow look more serious.

Can a black screen fix burn-in?

No. It is only a visual test surface.

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