Lighting technology
Colours of light
The colour of the light emitted by a light source. Light colour can be specified by means of x,y coordinates as a chromaticity coordinate in the → standard colorimetric system,…
Glossary
Cut-off angle
Angle above which no directed → reflection of the light source is visible in the → reflector. With Darklight reflectors or Darklight lenses, the cut-off angle is identical to the…
GlossaryLighting technology
Shielding angle
For downlights, the angle between the horizontal and a straight line running from the edge of the luminaire to the edge of the light source. In addition to the cut-off angle, a…
GlossaryLighting technology
Transadapter
Element for the mechanical and electrical connection of a luminaire, in particular a spotlight or floodlight, to a track; combined with an integrated electronic transformer or…
GlossaryLighting technology
Lamp life
The period over which a light source remains operational under defined operating conditions. Lamp life is often described using statistical parameters and serves to assess the…
GlossaryLighting technology
Intersecting beam
Hyperbolic shape due to the intersection of the light beam and the wall; produced, for example, by downlights.
GlossaryLighting technology
Mains voltage
The electrical voltage supplied through mains power distribution. In most regions of the world the mains voltage is 230 V at 50 Hz. Other supply voltages may require…
GlossaryLighting technology
Optical Cut-off
Analogous to the cut-off angle, the optical cut-off indicates the angle outside of which there is no glare. Whereas darklight reflectors have a screening effect, the angle here…
GlossaryLighting technology