Page 6 - Teiber Light Bulbs 2013

6 Light Bulb Resource Guide > Glossary

Glossary

Ballast Fluorescent Lamp
A device used with an electric-discharge lamp to obtain the A low pressure mercury electric discharge lamp, tubular in
necessary circuit conditions (voltage, current and wave form) shape in which a fluorescent coating (phosphor) transforms
for starting and operating; all fluorescent and HID light sources ultraviolet energy into visible light.
require a ballast for proper operation. Dimming ballasts are
special ballasts which when used together with a dimmer will Footcandle, FC
vary the light output of a lamp. A unit of illuminance equal to 1 lumen per square foot.

Beam Angle High Intensity Discharge (HID) Lamps
The angle between the two directions for which the intensity A general group of lamps consisting of metal halide
(candlepower) is 50% of the maximum intensity as measured and high pressure sodium lamps.
in a plane through the nominal beam centerline (center beam
candlepower). Measured in degrees, ie. spot = 9° Incandescent Filament Lamp
A lamp in which light is produced by a filament heated
Beam Spread
to incandescence by an electric current.
(In any plane) the angle between the two directions in the plane
in which the candlepower is equal to a stated percent (usually Lamp
ten percent) of the maximum candlepower in the A generic term for a man-made source of light;
beam (ie. flood, narrow spot). manufactured light source; the 3 broad categories of electric
lamps are incandescent, fluorescent, and high intensity
Center Beam Candle Power, CBCP
discharge (HID). Also known as light bulbs.
The intensity of light produced at the center of a reflector lamp,
expressed in candelas. Lumen, LM
A unit of luminous flux; the overall light output of a luminous
Color Rendering Index, CRI
source is measured in lumens.
The measure of a light source s ability to render the color of
objects "correctly," as compared with a reference source with M.O.L. Maximum Overall Length
comparable color temperature; the scale peaks at 100. The measurement from the top of the bulb to the bottom
of the base.
Correlated Color Temperature, CCT
A specification of the color appearance of a lamp relating Reflector
its color to that of a reference source heated to a particular A device used to redirect the light by the process of reflection.
temperature, measured in degrees Kelvin (K); CCT generally
measures the "warmth" or "coolness" of light source Voltage, E
appearance.
A measure of electrical potential, expressed in volts (V).
Efficacy
Watt, W
Efficiency of a light source expressed in lumens per watt A unit of electrical power equal to 1 joule per second.
(LPW or lm/W).
Filament
The wire (usually tungsten) that is heated to white heat by an
electric current passing through it.