Lighting products

Lighting products

Industry: Lights & lighting

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Lighting products

rapid start lamp

Lights & lighting; Lighting products

A fluorescent lamp with two pins at each end connected to the filament. The filaments are heated by the ballast to aid in starting. Some rapid start lamps may be instant started without filament ...

For most lamp types, rated lamp life is the length of time of a statistically large sample between first use and the point when 50% of the lamps have died. It is possible to define "useful life" of a ...

reflectance

Lights & lighting; Lighting products

The ratio of light reflected from a surface to that incident upon it.

reflector lamp (R)

Lights & lighting; Lighting products

A light source with a built-in reflecting surface. Sometimes, the term is used to refer specifically to blown bulbs like the R and ER lamps; at other times, it includes all reflectorized lamps like ...

room cavity ratio (RCR)

Lights & lighting; Lighting products

A shape factor (for a room, etc.) used in lighting calculations. RCR = 5H (L+W) / L x W, or, alternately; RCR = (2.5) Total Wall Area / Floor Area; Where H = height, L = length and W = width of the ...

scotopic

Lights & lighting; Lighting products

Vision where the rods of the retina are exclusively responsible for seeing, typically like the light levels in the countryside on a moonless, starlit night (See also PHOTOPIC, FOVEA, FOVEAL VISION ...

scotopic/photopic (S/P) ratio

Lights & lighting; Lighting products

This measurement accounts for the fact that of the two light sensors in the retina, rods are more sensitive to blue light (scotopic vision) and cones to yellow light (photopic vision). The ...