Patent ID: 7844145

Claim:
A system, comprising: a first Fabry-Perot interferometry channel having a first free spectral range (FSR) and a first resolving power (RP); a second Fabry-Perot interferometry channel having a second FSR and a second RP, serially and optically coupled to the first Fabry-Perot interferometry channel, wherein the first FSR is greater than the second FSR and the first RP is less than the second RP, wherein the first and second FSR are calculated by the equation Δ ⁢ ⁢ f = c 2 ⁢ ⁢ nd ⁢ ⁢ cos ⁢ ⁢ ( θ ) and the first and second RP are calculated by the equation RP = λ Δ ⁢ ⁢ λ = NF = N ⁢ 4 ⁢ ⁢ R ( 1 - R ) 2 = 2 ⁢ ⁢ nd λ ⁢ 4 ⁢ R ( 1 - R ) 2 , ⁢ where ⁢ ⁢ Δ ⁢ ⁢ λ = λ 2 2 ⁢ ⁢ nd ⁢ ⁢ and ⁢ ⁢ Δ ⁢ ⁢ k = 2 ⁢ ⁢ π ⁢ ⁢ Δ ⁢ ⁢ f c ; and a controller configured to commonly control the first Fabry-Perot interferometry channel and the second Fabry-Perot interferometry channel in unison to dynamically track an optical wavelength.