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Standard Spectral Lines

Definition: spectral lines which are often used as wavelength references

German: Standard-Spektrallinien

Category: general optics

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Certain spectral lines – usually from common low-pressure gas discharge lamps used as spectral lamps – are frequently used as wavelength references. There are also laser lines which can fulfill similar purposes.

The refractive indices of optical materials (mostly optical glasses) are often specified at a number of standard wavelengths, in particularly at the lines C, C', D, d, e, F and F' (see Table 1).

365.0146 nmultravioletimercury
404.6561 nmviolethmercury
435.8343 nmbluegmercury
479.9914 nmblueF'cadmium
486.1327 nmblueFhydrogen
543.5 nmgreengreen HeNehelium–neon laser
546.074 nmgreenemercury
587.5618 nmyellowdhelium
589.2938 nmorangeDsodium
632.8 nmredred HeNehelium–neon laser
643.8469 nmredC'cadmium
656.2725 nmredChydrogen
706.5188 nmredrhelium
852.11 nminfraredscesium
1013.98 nminfraredtmercury

Table 1: Table of spectral lines which are frequently used in optics.

See the article on laser lines for many more lines generated with lasers.

See also: spectral lines, spectral lamps, wavelength, gas discharge lamps, laser lines
and other articles in the category general optics


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