Page 47 - Tunable Lasers Handbook
P. 47
28 F. J. Duarte
given that a@,,,/dA = a@,,fah = . . . = a@,,,fah.
The transmission maxima for an etalon is given by [50]
where me is an integer, de the space between the reflective surfaces, and is the
refraction angle. The angular dispersion for an etalon is given by [2]
where
In addition to the ray matrix given in Table 2, further parameters of interest
for intracavity etalons include the free spectral range (FSR)
FSR = h2/(2nd,) in wavelength units (m)
= c/(~Iz~,) frequency units (HZ)
in
= 1/(2nd,) in wave numbers (m- l) .
Also, the effective finesse is given by [41]
where FR, F,, and represent the reflective, flatness, and aperture finesses,
respectively, The reflective finesse is a function of the reflectivity of the surfaces
[401
and the minimum resolvable bandwidth provided by the etalon is given by the
ratio FSR/z
