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The interference that arises when an attempt is made to place a telephone call just as an incoming call is arriving; in the case of data transmission under the control of a computer, this can render the line or even the computer temporarily inoperative.
Discomfort produced in an observer by one or more visible sources of light. Also known as discomfort glare.
Visual disability caused by visible sources or areas of luminance which are in an observer's field of view but do not assist in viewing. Also known as disability glare.
Dazzling brightness of the atmosphere, caused by excessive reflection and scattering of light by particles in the line of sight.


A state that reduces the ability to perceive the visual information needed for a particular activity. It arises when some parts of the visual field are much brighter than their surroundings.

blinding glare

So intense that for an appreciable length of time after it has been removed, no visual perception is possible.

discomfort glare

Glare that is distracting or uncomfortable, interfering with the perception of visual information required to satisfy biological needs, it does not significantly reduce the ability to see information needed for activities.

direct glare

Results from high luminances directly visible from a viewer’s position.

disability glare

Reduces the ability to perceive the visual information needed for a particular activity.

reflected glare

The reflection of incident light that partially or totally obscures the surface details by reducing the contrast on a surface.


The sensation produced by brightnesses within the visual field that are sufficiently greater than the luminance to which the eyes are adapted to cause annoyance, discomfort, or loss in visual performance and visibility.
References in periodicals archive ?
Far too often, we see large expanses of glass with little ability to control the distribution of daylight or eliminate the glare associated with direct sunlight penetration," Holtz explains.
A good example of how visual comfort is being ignored is the recent adaption of LEDs to street and highway luminaires, where many of them are unshielded glare balls.
For later usage in glare calculation and for obtaining accurate work plane illuminance, in the ray tracing method, a 40-by-40 grid size is applied for each interior surface, and for work plane illuminance and vertical illuminance, a 3-by-3 grid size is used.
The inventor of the Phone Glare now seeks a third party licensee to manufacture, market, and distribute the product for him under a royalty agreement.
Amongst the many topics covered, we learnt the importance of reducing glare and the crucial role of macular pigment and macular health to maintain great vision throughout life.
Within the UGR system, a value of 16 corresponds to perceptible glare, 19 to just acceptable glare, and 22 to unacceptable glare.
The camera itself analyzes the image and scans it for glare that exceeds a certain threshold.
This demonstration was a part of a government initiated R & D project on road safety with an objective of reducing the glare from the vehicle headlights and also to improve the road visibility.
Having them available for that odd hour or so before sunset when the glare can prevent you seeing a pedestrian, cyclist or overtaking car around the next corner can be a real lifesaver.
Apparently, the more professional sky watchers are also much disturbed by this unnecessary upwards glare, some having to travel far into the countryside to observe the heavens.