luminous efficiency การใช้

• For example, a typical incandescent light bulb has a luminous efficiency of only about 2 %.
• Because most people have a point of maximum luminous efficiency that is off-center, the antagonistic chromostereoptic effects.
• Multiplying radiance by luminous efficiency : the planet night's side is 1000 times dimmer than HD's photosphere.
• Two very similar measurement systems were created to bridge the scotopic and photopic luminous efficiency functions, creating a unified system of photometry.
• The "'luminosity function "'or "'luminous efficiency function "'describes the average spectral sensitivity of human visual perception of brightness.
• The integrals of the XYZ color matching functions must all be equal by requirement 3 above, and this is set by the integral of the photopic luminous efficiency function by requirement 2 above.
• All test methods specify that measurements should be made with visible light according to CIE spectral luminous efficiency function V ( ? ) in the CIE 1931 standard observer and CIE standard illuminant C.
• The ASTM Method states that the illumination should be defined such that the source-detector combination is spectrally corrected to give the CIE luminous efficiency, V ( ? ), with CIE illuminant SC.
• There are many non-incandescent light sources, such as the fluorescent lamp, high-intensity discharge lamps and LED lamps, which have higher luminous efficiency, and some have been designed to be retrofitted in fixtures for incandescent lights.
• The combination of these properties yields a mantle that, when heated by a kerosene or liquified petroleum gas flame, emits intense radiation that is mostly visible light, with relatively little energy in the unwanted infrared, increasing the luminous efficiency.
• Within the visible spectrum, wavelengths of light are weighted according to a function called the " photopic spectral luminous efficiency . " According to this function, 700 nm red light is only about 0.4 % as efficient as 555 nm green light.
• In practice, most buildings that use a lot of lighting use fluorescent lighting, which has 22 % luminous efficiency compared with 5 % for filaments, so changing to LED lighting would still give a 34 % reduction in electrical power use and carbon emissions.
• The luminous " efficiency " is defined as the ratio of the luminous efficacy to the theoretical maximum luminous efficacy of 683 lpw, and, as for luminous efficacy, is of two types, radiant luminous efficiency ( LFR ) and source luminous efficacy ( LFS ).
• This means that white ( or whitish ) light sources produce far fewer lumens per watt than the theoretical maximum of 683.002 lm / W . The ratio between the actual number of lumens per watt and the theoretical maximum is expressed as a percentage known as the luminous efficiency.
• Lattice constants of the compounds also tend to be different, and the lattice mismatch against the substrate, dependent on the mixing ratio, causes defects in amounts dependent on the mismatch magnitude; this influences the ratio of achievable radiative / nonradiative recombinations and determines the luminous efficiency of the device.