摘要 |
A method for determining spectral calibration data (λcal(Sd), Sd,cal(λ)) of a Fabry-Perot interferometer (100) comprises: - forming a plurality of filtered spectral peaks (P'1, P'2) by filtering input light (LB1) with a Fabry-Perot etalon (50) such that a first filtered peak (Ρ'1) corresponds to a first transmittance peak (P1) of the etalon (50), and such that a second filtered peak (P'2) corresponds to a second transmittance peak (P2) of the etalon (50), - using the Fabry-Perot interferometer (100) for measuring a spectral intensity distribution (M(Sd)) of the filtered spectral peaks (Ρ'1, P'2), wherein the spectral intensity distribution (M(Sd)) is measured by varying the mirror gap (dFP) of the Fabry-Perot interferometer (100), and by providing a control signal (Sd) indicative of the mirror gap (dFP), and - determining the spectral calibration data (λcal(Sd), Sd,cal(λ)) by matching the measured spectral intensity distribution (M(Sd)) with the spectral transmittance (ΤΕ(λ)) of the etalon (50). |