The transmission and the peak transmission wavelengths
of a Fabry-Perot etalon equals:
and
(Atherton 1987), where T and R are the transmission and
reflection coefficients of each surface, t
is the Fabry-Perot cavity spacing and N is the interference order.
Except where mentioned differently, I will assume the values given by
Cavallini (1998) for a Queensgate Fabry-Perot etalon: R =
0.95, nm, t = 3 mm,
and a telecentric beam
with an f-ratio of f/192.
I will assume in this note perfect optical quality for the
Fabry-Perot plates and a
normal incidence angle of the central ray on the etalon.
With these parameters N equals 10909 and
the Fabry-Perot FWHM in collimated light 0.823 pm.
The wavelength shift across the pupil equals 1.865 pm.