Luminance The per square (cd/m²) is the SI unit of ; nit is a non-SI name also used for this unit. It is often used to quote the of computer displays, which typically have luminance’s of 50 to 300 nits (the sRGB spec for monitor’s targets 80 nits). Modern flat-panel (LCD and plasma) displays often exceed 300 cd/m² or 300 nits. The term is believed to come from the Latin "nitere" = to shine. 1 Kilocandela per square metre 10-3 Candela per square 10-4 Candela per square foot 0,09 Foot- 0,29 Lambert 3,14×10-4 Nit 1 10-4 Luminance is a photometric measure of the density of luminous in a given direction. It describes the amount of that passes through or is emitted from a particular , and falls within a given solid . The SI unit for luminance is candela per square metre (cd/m2). The CGS unit of luminance is the stilb, which is equal to one candela per square centimetre or 10 kcd/m2 The (symbol: lx) is the SI unit of illuminance and luminous emittance. It is used in as a measure of the intensity of light, with weighted according to the function, a standardized model of human brightness perception. In English, "lux" is used in both singular and plural. Microlux 1000000 Millilux 1000 Lux 1 Kilolux 10-3 per square metre 1 Lumen per square centimetre 10-4 Foot- 0,09 10-4 Nox 1000 In photometry, illuminance is the total luminous incident on a surface, per unit area. It is a measure of the intensity of the incident light, -weighted by the luminosity function to correlate with human Gwent Electronic Materials Ltd. Telephone:- +44 (0) 1495 750505 Monmouth House, Applied Enzyme Technology Ltd. Telefax :- +44 (0) 870 052 8250 Mamhilad Park, Gwent Biotechnology Systems Ltd. E-Mail :- [email protected] Pontypool, Gwent Sensors ltd. Web Site :- http;//www.gwent.org Torfaen, LRH Ltd. NP4 0HZ United Kingdom Page 1 of 2 brightness perception. Similarly, luminous emittance is the per unit area emitted from a surface. Luminous emittance is also known as luminous exitance.

Luminous In photometry, is the perceived energy of light. This is sometimes also called the of light. Talbot 3600 Lumen 3600 Lumen 60 Lumen 1 Luminous energy is not the same as the , the corresponding objective . This is because the human eye can only see light in the visible and has different sensitivities to light of different wavelengths within the spectrum. When adapted for bright conditions (), the eye is most sensitive to light at a wavelength of 555 nm. Light with the same at longer or shorter wavelengths has a lower luminous energy

Luminous flux Lumen 1 Candela 1 Lux square metre 1 In photometry, luminous flux or luminous power is the measure of the perceived power of light. It differs from , the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light

Candela 1 Lumen per steradian 1 Hefnerkerze 1,11 1,02 In photometry, luminous intensity is a measure of the wavelength-weighted power emitted by a light source in a particular direction per unit , based on the luminosity function, a standardized model of the sensitivity of the human eye. The SI unit of luminous intensity is the candela (cd), an SI .

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