colorimeter

[8.5.1] An instrument that measures color in units specific to a color space such as the CIE 1931 Chromaticity Diagram, the CIE 1964 Chromaticity Diagram, CIELAB, or CIELUV. See also […]

center-beam candlepower (CBCP)

[8.6.4.3] The luminous intensity along the geometric centerline of a directional light source. The assumption in application is usually that the centerline candlepower is also the maximum candlepower.  Also called […]

isoluminance line

[8.6.6] A line on a surface that shows all the points where the luminance is the same for a given position of an observer and light source(s) in relation to […]

lux meter

[8.4.9]  [See illuminance (lux or footcandle) meter.]

lamp failure

[8.20] The point where a lamp stops operating. Lamp failures from manufacturing defects are reported but not included in the calculation of lamp life. For certain lamp types, other criteria […]