Glare

Glare is visual discomfort or visibility loss from bright light in the field of view.

Glare is visual discomfort or reduced visibility caused by bright sources, reflections or contrast in the field of view.

Technical meaning

  • Glare depends on brightness, viewing direction, contrast, luminaire position and the observer's task.
  • It can come from visible fittings, reflected light on screens or shiny surfaces, daylight apertures or outdoor floodlights.
Observer, source and reflection pathGlare notes start with the observer view and source path; they do not come from average lux alone.Geometry only; formal glare assessment needs the relevant method and project data.

Calculation use

  • Beam and room estimates can flag likely glare issues when fittings are bright, low, poorly shielded or aimed toward normal viewing positions.
  • UGR and other glare discussions need more detailed layout and viewing information than a simple lumen count.

Not the same as

  • Glare is not brightness alone. A high-output fitting can be comfortable if distribution and viewing position are controlled.
  • Glare is not solved by reaching a target lux value.

Australian context

  • Australian offices, workshops, outdoor areas and hospitality interiors should note glare views separately from average illuminance.

Examples

ExampleValuePlanning note
Screen reflectionreflected glareA bright fitting or window can reduce screen comfort even when lux is adequate.
Floodlight aimdirect viewLight aimed across a boundary or toward eyes can be uncomfortable.
Low downlightbright apertureFixture position and shielding can matter as much as output.

Calculation limits and records

  • This page explains glare for early lighting notes. Formal glare assessment needs the relevant method, observer positions and luminaire data.

Related pages