A plane air-spaced Fabry-Perot etalon ( ) is characterised spectrally: its free…

PHYSICS · Multi-part · Fermi University Physics · Mathematical Methods for Physics · Optics & Photonics · Interference and diffraction

What an Instrument Can See, Ch Multiple beams: the stack as a matrix and the etalon as a filter

Problem

A plane air-spaced Fabry-Perot etalon (

n=1

) is characterised spectrally: its free spectral range is

\mathrm{FSR} = 2.0\,\text{GHz}

and its measured finesse is

\mathcal F = 250

. ((a)) Find the mirror spacing

d

. ((b)) Find the mirror power reflectance

R

that gives this finesse. ((c)) Find the photon lifetime

\tau_p

and the quality factor

Q

\lambda_0 = 633\,\text{nm}

, and write the impulse response

h(t)

as a delta train with its round-trip spacing and amplitude decay factor. Take

c = 3.00\times10^8\,\text{m s}^{-1}