Light+vocabulary

A light source containing an arc (see above). Also called a discharge lamp, or an arc discharge lamp Brightness can refer to any of several technical terms used in lighting and is, therefore, ambiguous A chandelier is often the focal point of the dining room. As such it should be hung about 30 inches above the tabletop and should be at least 6 inches narrower than the table on each side.  **A lamp resembling the color of daylight, typically with a color temperature of 5500 K to 6500K Generally refers to a compact fluorescent lamp containing 4 U-shaped tubes, i.e. Quad Biax®, as opposed to Triple Biax® (3 tubes) and Double Biax® (2-tubes). A small light fixture recessed into the ceiling that usually concentrates the light in a downward direction. Synonyms: downlight, can, recessed can. **Sky Glow ** Also, known as "light pollution". The "haze" or "glow" that surrounds highly populated areas and reduces the ability to view the nighttime sky. Specifically, light that enters the sky from an outdoor lighting system by indirect light reflected from atmospheric particles such as fog, dust, or smog. 
 * Arc Lamp **
 * Brightness **
 * Chandelier **
 * Daylight Lamp
 * Quad **
 * Recessed Downlight **

<span style="font-family: Calibri,sans-serif;">Lighting that is specifically installed to light an area where a task is performed
 * <span style="font-family: Calibri,sans-serif;">Task Lighting **



<span style="font-family: Calibri,sans-serif;">The percentage of lamp lumens directed from a luminaire (light fixture) at or above 90 degrees.
 * <span style="font-family: Calibri,sans-serif;">Uplight **

<span style="font-family: Calibri,sans-serif;"> The task associated with seeing; objects and details that must be seen to perform an activity.
 * <span style="font-family: Calibri,sans-serif;">Visual Task **



<span style="font-family: Calibri,sans-serif;"> The distance between two neighboring crests of a traveling wave. The wavelength of light is between 400 and 700 nanometers. <span style="font-family: Calibri,sans-serif;">
 * <span style="font-family: Calibri,sans-serif;">Wavelength **