Glare
Blinding Glare
Direct Glare
Discomfort Glare
Disability Glare
Reflected Glare
Veiling Luminance
Veiling Reflection

(Terms of lighting design/physiology)

Glare is an interference with visual perception caused by an uncomfortably bright light source or reflection; a form of visual noise.

In its simplest form, glare is a consequence of the normally helpful capability of the human eye to adapt to different light levels. In the case of glare, the eye adapts to the high level of the glare source, which makes it hard to perceive details in the now "too dark" work area.

Direct Glare is glare resulting from high luminances in the visual environment that are directly visible from a viewers position. Examples can be a sunlit surface inside or outside a building, or an insufficiently shielded luminaire.

Reflected Glare or Veiling Reflection is a reflection of incident light that partially or totally obscures the details to be seen on a surface by reducing the contrast.

Discomfort Glare is glare which is distracting or uncomfortable, which interferes with the perception of visual information required to satisfy biological needs, but which does not significantly reduce the ability to see information needed for activities.

Disability Glare is glare which reduces the ability to perceive the visual information needed for a particular activity. Disability glare is caused by light scattered within the eye, causing a haze of veiling luminance that decreases contrast and reduces visibility.

Blinding Glare is glare which is so intense that for an appreciable length of time after it has been removed, no visual perception is possible.