An Updated Edlén Equation for the Refractive Index of Air
- 1 January 1993
- journal article
- Published by IOP Publishing in Metrologia
- Vol. 30 (3) , 155-162
- https://doi.org/10.1088/0026-1394/30/3/004
Abstract
The Edlén equation for the refractive index of air, published in 1966, is still widely used. Subsequent to its formulation, however, improved data have become available on the density of air and the refractivity of water vapour. The practical temperature scale has also been revised and the carbon dioxide content of normal laboratory air has increased. These effects result in a discrepancy of typically 1 × 10-7. The consequent revision of the equation brings the agreement between calculation and experiment within an experimental uncertainty of ± 3 × 10-8.Keywords
This publication has 14 references indexed in Scilit:
- Verification of Revised Water Vapour Correction to the Index of Refraction of AirMetrologia, 1992
- The International Temperature Scale of 1990 (ITS-90)Metrologia, 1990
- The results of a comparison between calculated and measured values of the refractive index of airJournal of Physics E: Scientific Instruments, 1988
- Measurements of the Refractive Index of Air Using Interference RefractometersMetrologia, 1986
- The Refractive Index of Moist Air in the 3-μm RegionMetrologia, 1982
- Length Measurement of Gauge Blocks Using a 3.39 µm He-Ne Laser InterferometerJapanese Journal of Applied Physics, 1980
- The air density equation and the transfer of the mass unitJournal of Research of the National Bureau of Standards, 1978
- Optical Refractive Index of Air: Dependence on Pressure, Temperature and CompositionApplied Optics, 1967
- The Refractive Index of AirMetrologia, 1966
- The refraction and dispersion of air and dispersion of air for the visible spectrumPhilosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1939