Backlight Bleed Test

This test renders a pure black screen. It is designed to expose backlight bleed, clouding, or IPS glow that typically affects LCD/LED panels.

Pure Dark Field Inspection (0%)Hover to view controls • Press Fullscreen for dark room testing

Background:

Hardware Boundary Notice

Smartphone cameras and long exposures drastically exaggerate both backlight bleed and IPS glow due to camera sensor gain. Never judge backlight uniformity from photos. Furthermore, nearly all in-plane switching (IPS) panels have inherent optical glow when viewed off-angle; this is normal liquid crystal physics, not a manufacturing defect.

1. Dark Room Requirement: Perform this inspection in a completely dark room at your standard calibrated brightness (typically 120–150 nits).

2. Distinguish Fixed vs Moving: Fixed torch-like light beams along edges indicate mechanical bezel pinch (bleed). Diffuse corner sheen that disappears as you move directly in front of the corner is IPS glow.

3. Step Back 1 Meter: Sit at standard operating distance. Severe corner glow viewed from 12 inches away is often optical perspective rather than panel failure.

4. OLED Comparison: True self-emissive OLED panels have complete pixel shut-off at 0% with zero glow or bleed.

How to test

WHAT TO CHECK: This test must be performed in a completely dark room.
HOW TO USE: Set your monitor to its standard or calibrated brightness level (do not force 100% brightness unless that is how you normally use it).
WHAT YOU MAY NOTICE: Look at the corners and edges of the screen. Backlight Bleed appears as distinct patches of white/yellow light leaking from the bezel. IPS Glow shifts and changes intensity as you move your viewing angle.

Learn more in the Knowledge Base • Backlight Bleed vs. IPS Glow: How to Tell the Difference

Read Technical Guide

Having trouble with this test? • Backlight Bleed vs. IPS Glow

Troubleshooting Guide

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How to test

WHAT TO CHECK: This test must be performed in a completely dark room.
HOW TO USE: Set your monitor to its standard or calibrated brightness level (do not force 100% brightness unless that is how you normally use it).
WHAT YOU MAY NOTICE: Look at the corners and edges of the screen. Backlight Bleed appears as distinct patches of white/yellow light leaking from the bezel. IPS Glow shifts and changes intensity as you move your viewing angle.