symbol: $\lambda$, units: $\pu{m}$, $\pu{\upmu\!m}$, $\pu{nm}$
synonym: wavelength
https://doi.org/10.1351/goldbook.08299
Distance travelled by a wave of electromagnetic radiation in one cycle in a non-absorbing medium of real refractive index \(n\). \(\lambda = \lambda_{0}/n\).
Notes:
- In spectroscopy, the unqualified term 'wavelength' frequently means the vacuum wavelength, and symbol \(\lambda\) frequently means \(\lambda_{0}\).
- SI unit: \(\pu{m}\). Common unit: \(\pu{nm}\) or \(\pu{\upmu\!m}\).