I need a custom etalon, but dont know how to order one so I get exactly what I need. What should I specify?
We get this type of question all the time. In order to properly specify an etalon, you need to tell us the operating wavelength range, operating temperature (and temperature tuning range, if applicable), angle of incidence (it is best to keep this to less than 0.5 to minimize beam walkoff effects), clear aperture, input beam size, and any other operating conditions specific to you application. In addition, youll need to let us know the free-spectral range or FSR (the distance between the transmission peaks) and the finesse (the ratio of the FSR to the FWHM of the transmission peak). The finesse can also be specified in terms of the FHWM, or because this is directly related to the reflectivity, you can tell us your desired mirror reflectivity. It will also be important to note if you need to center the transmission peak on a reference such as the ITU grid or an absorption line. Weve added an etalon calculator to our website to help you design the key parameters of your etalon. Give us a
