(2) Colors of Light & Artificial Lighting Flashcards
the ability to distinguish and interpret different wavelengths of visible light
color perception
the ability to distinguish fine details; it is the “keenness” of vision that is necessary to perform tasks such as reading, writing, drafting, sewing, or surgery
visual acuity
a device that generates light
lamp
a complete lighting unit, which consists of a lamp (or lamps), lamp socket(s), any lenses, refractors, or louvers, any ballast (or ballasts), and the housing
luminaire
the luminaire less the lamp(s); it includes the structural parts of a luminaire including any lenses, mounting supports, wiring, and ballasts, but does not include the lamps
light fixture
_____ + _____ = luminaire
lamp + fixture
the measure of the perceived power of light expressed in lumens (lm)
luminous flux
the amount of light shaking a 1.0 ft2 surface that at all points is held one foot away from the flame of a standard candle (roughly one candela of intensity)
lumen
the SI unit of luminous intensity—that is, the power emitted by a light source in a particular direction
candela (cd)
the ratio of the light output of a light source (a specific lamp) to the electrical energy consumed to produce that light source
LPW = (light output (lm) /(power input (W)
luminous efficacy
color of lamp rating, Kelvin (K)
correlated color temperature (CCT)
color temperature less than about 3500 K
warm lighting
color temperature greater than about 5000 K
cool lighting
color temperature of the lamp is between temperatures of 4500 and 6500 K
daylighting
color temperature of warm light
3000 K