Datasheet

GLOSSARY OF TERMS
TERMINOLOGY DESCRIPTION
Beam Angle It is the angular dimension of the cone of light from reflectorized lamps
encompassing the central part of the beam out to the angle where the intensity is
50% of maximum.
Correlated Colour
Temperature (CCT)
A specification of the colour appearance of a lamp relating its colour to that of a
reference source heated to a particular temperature, measured in degrees Kelvin
(K).
Colour Temperature (K) The colour temperature of a light source is defined in comparison with a “black
body radiator” and plotted on a “Planckian curve”. Colour temperature or the colour
effect of the light source is presented in Kelvin (K). The typical colour temperatures
are: 3500K and below is warm white; 3500K-4500K is neutral white; around 4500K
or higher is cool white.
Colour rendering Index (CRI) The colour rendering index is a measure of the correspondence between the
colour of an object and its appearance under a light source. The higher the colour
rendering index of the light source, the more naturally the colours of the object are
rendered.
Heat Sink A heat sink is an enclosure that serves to radiate the heat from the LED lamp.
Materials with good thermal conductivity are used here to transfer the heat
generated inside the lamp to the surrounding air.
Illuminance The density of light arriving on a surface. Illuminance is measured in footcandles or
lux.
Incandescent Lamp A light source that generates light utilizing a thin filament wire heated to white heat
by an electric current passing through it.
LED Light Emitting Diodes or LED is a semiconductor device that illuminates by the
movement of electrons in the material. It is a solid that directly converts electrical
impulses into light. Most white light LEDs incorporate phosphors to change the
colour characteristics of the emitted light.
Luminaire It is a complete lighting unit consisting of a lamp (or lamps), ballast (or ballasts)
as required together with the parts designed to distribute the light, position and
protect the lamps and connect them to the power supply. A luminaire is also called
a fixture.
Luminous flux (lm) It is a measure of the amount of light emitted by a light source and is presented in
Lumens (lm).
Luminous Intensity (cd) Luminous intensity indicates the strength of light in a particular direction and is
presented in candela (cd).
Lux (lx) A unit of illuminance or light falling onto a surface. One lux is equal to one lumen
per square metre. Ten lux approximately equals one footcandle.
Organic light emitting diode An organic light emitting diode (OLED) is a light-emitting diode (LED) in which the
emissive electroluminescent layer is a film of organic compounds which emit light in
response to an electric current.
Phosphor An inorganic chemical compound processed into a powder and deposited on the
inner glass surface of fluorescent tubes and some mercury and metal-halide lamp
bulbs. Phosphors are designed to absorb short wavelength ultraviolet radiation and
to transform and emit as visible light. Phosphors are also used in LED devices to
create white light when used in combination with LEDs of certain wavelengths.
Watt A unit of electrical power. Lamps are rated in watts to indicate the rate at which they
consume energy.
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Lighting
LED
Verbatim | TECHNICAL INFORMATION