Definition of etalon in English:

Share this entry


Pronunciation: /ˈɛtəlɒn/


A device consisting of two reflecting glass plates, employed for measuring small differences in the wavelength of light using the interference it produces.
Example sentences
  • The change in resonance frequency of the etalon measures the change in optical-path length.
  • We specialize in very large aperture etalons with diameters up to 150 mm.
  • Our products range from simple condenser lenses to precision etalons.


Early 20th century: from French étalon, literally 'standard of measurement'.

For editors and proofreaders

Line breaks: eta¦lon

Share this entry

What do you find interesting about this word or phrase?

Comments that don't adhere to our Community Guidelines may be moderated or removed.