Light+Vocabulary

Intense luminous discharge formed by the passage of electric current in a gaseous medium across a space between electrodes. An auxiliary piece of equipment required to start and to properly control the flow of current to gas discharge light sources such as fluorescent and high intensity discharge (HID) lamps. Typically, magnetic ballasts (also called electromagnetic ballasts) contain copper windings on an iron core while electronic ballasts are smaller and more efficient and contain electronic components. Sound generated by the vibration of laminations in the iron core of the transformer or inductor present in the ballast. **Ballast Losses** Power or energy dissipated in the ballast as heat and not converted to lamp energy A style of bulb base which uses keyways instead of threads to connect the bulb to the fixture base. The bulb is locked in place by pushing it down and turning it clockwise. Windings of copper or aluminum wire surrounding the steel core in ballast. Also refers to the entire assembly comprising the inductor or transformer. Used to refer to the beam pattern of a reflector lamp, which disperses the light over a wide beam angle, typically 20 degrees or more. A luminaire used to light a scene or object to a level much brighter than its surroundings. Usually floodlights can be aimed at the object or area of interest. A measure of the luminous flux or quantity of light emitted by a source. For example, a dinner candle provides about 12 lumens. A 60-watt Soft White incandescent lamp provides about 840 lumens. A measure of "surface brightness" when an observer is looking in the direction of the surface. It is measured in candelas per square meter (or per square foot) and was formerly referred to as "photometric brightness. Alandscape lighting technique used to create a distinct outline or silhouette of plants or other objects
 * Arc**
 * Ballast**
 * Ballast Hum**
 * Bayonet**
 * Coil**
 * Flood**
 * Floodlight**
 * Lumens**
 * Luminance**
 * Silhouetting**