Glossary--Lighting words and specification explaination
Accent lighting
The highlighting of individual features
Adaption
The process whereby eyesight adjusts to relative levels of brightness, e.g. daytime or night time
Asymmetric reflector
A reflector that distributes light differentially in specific directions
Baffle
A shield type of apparatus to prevent light spill from a luminaire
Beam angle
The angle over which the intensity from a reflector drops to half of the peak value
Candela
A measure of luminous intensity from a lamp
Colour appearance
The relative perception of warmth of light, warm, intermediate or cool. (See also correlated colour temperature)
Colour rendering index (CRI)
The relative ability of a light source to enable the identification of colour
Correlated colour temperature (CCT)
The numeric expression of colour appearance, expressed in Kelvin
Contrast
The subjective appearance of different levels of lighting within the visual field
DALI
Stands for Digital Addressable Lighting Interface and is a standardised communication protocol used with electronic control gear such as LED Drivers. Many CMS systems use DALI interface to communicate with street lighting equipment
Diamond Optic®
Award winning adjustable reflector system that tailors light distribution to the area to be lit.
Diffuse lighting
Lighting that emanates in many directions with no peak intensity in any given direction
Diffuser
Translucent or frosted glazing that engenders a more even light distribution
Direct entry luminaire
Luminaire where the connection between it and the column is via an offset spigot
Direct lighting
Lighting where the target area is lit directly from the luminaire rather than via another surface
Disability glare
Light that adversely affects one’s ability to undertake a given visual task
Discomfort glare
Light that makes a given visual task uncomfortable
Easy-fit™ connector
The preferred connector between a pendant luminaire and its bracket that resolves all the problems associated with the more dated screw type connectors
Full cut off luminaire
Expression for luminaires where there is an absolute cut off of light above the horizontal. For further information on G4, G5 and G6 glare ratings see EN 13201
Glare
That light emitted by a luminaire that has an adverse effect on a given visual task