Hauptkatalog - LED Linear

27/08/2012
Term Symbol Unit Formula Explanation
luminous flux,
luminous power
Glossar Glossary
Φ Lumen (lm) Luminous flux is the radiated power of a light source including
the spectral sensitivity of the human eye.
luminous intensity I Candela (cd) I = Φ/ω Luminous intensity is an expression of the amount of light
power emanating from a point source within a solid angle of
one steradian.
Illuminance E Lux (lx) E = Φ/A Illuminance is the total incident luminous flux on a surface
per unit area.
Luminance L (cd/m 2 ) L = I/A
(L = I/A cos Φ)
Illuminance is the luminous intensity per unit area of light
in a given direction and angle.
Luminance distribution Luminance distribution is the ratio of different areas and their corresponding
luminances.
Luminous color Warm white,
neutral white,
cold white
Correlated Color
Temperature (CCT)
Color Rendering Index
(CRI)
Luminance color describes ranges of correlated color temperatures
(CCT).
Kelvin (K) The correlated color temperature of e light source is equal
to the temperature of an ideal black body radiator.
Ra Ra index The Color Rendering Index is a quantitative measure of the ability of a
light source to reproduce the colors of various objects faith fully in
comparison with an ideal or natural light source. The maximum Ra =
100 means the light source radiation is equal to an ideal black body
radiator.
luminous efficacy η lm/W η = Φ/P Luminous efficacy is the ratio of luminous flux to power.
The power can be either the radiant flux of the source‘s output,
or it can be the total electric power consumed by the source.
Uniformity E min /E mid L min /L mid Ratio of different areas of Illuminances.
Glare Glare influences the visibility of details and the eyesight.
Categories are (URG/NB) and (TI/°).
Efficiency η % The efficiency is the ratio between the total luminous flux emitted by a
device and the total amount of input power .
Life time L 70 Zeit (h) The life time describes the time of degradation of the light source, e.g.
the time in which the light output decreased to 70%.
365