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Lambert (unit)
The lambert (symbol L, la or Lb) is a non- SI metric unit of luminance named for Johann Heinrich Lambert (1728–1777), a Swiss mathematician, physicist and astronomer. A related unit of luminance, the foot-lambert, is used in the lighting, cinema and flight simulation industries. The SI unit is the candela per square metre (cd/m2). Definition 1 lambert (L) = \frac candela per square centimetre (0.3183 cd/cm2) or \frac cd m−2 See also Other units of luminance: * Apostilb (asb) * Blondel (blondel) * Bril Bril is a surname. Notable people with the surname include: *Ben Bril, Dutch boxer *Joel Bril, pen name of Joel Löwe *Matthaeus Bril, Flemish painter *Paul Bril, Flemish painter, brother of Matthaeus See also * Brill (other) * Brühl (d ... (bril) * Nit (nit) * Stilb (sb) * Skot (sk) {{SI light units References "Lighting Design Glossary: Luminance" at ''Schorsch Lighting Design Knowledgebase'' Units of luminance Non-S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metric Units
Metric units are units based on the metre, gram or second and decimal (power of ten) multiples or sub-multiples of these. The most widely used examples are the units of the International System of Units (SI). By extension they include units of electromagnetism from the CGS and SI units systems, and other units for which use of SI prefixes has become the norm. Other unit systems using metric units include: * International System of Electrical and Magnetic Units * Metre–tonne–second (MTS) system of units * MKS system of units (metre, kilogram, second) Metric units that are part of the SI The first group of metric units are those that are at present defined as units within the International System of Units (SI). In its most restrictive interpretation, this is what may be meant when the term ''metric unit'' is used. The SI defines 30 named units and associated symbols: * The unit one (1) is the unit of a quantity of dimension one. * The second (s) is the unit of time. * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminance
Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through, is emitted from, or is reflected from a particular area, and falls within a given solid angle. Brightness is the term for the ''subjective'' impression of the ''objective'' luminance measurement standard (see for the importance of this contrast). The SI unit for luminance is candela per square metre (cd/m2). A non-SI term for the same unit is the nit. The unit in the Centimetre–gram–second system of units (CGS) (which predated the SI system) is the stilb, which is equal to one candela per square centimetre or 10 kcd/m2. Description Luminance is often used to characterize emission or reflection from flat, diffuse surfaces. Luminance levels indicate how much luminous power could be detected by the human eye looking at a particular surface from a particular angle of view. Luminance is thus an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
