Spectral characterization of integrated acousto-optic tunable filters by means of laser frequency modulation spectroscopy.
The spectral characteristics of an integrated acousto-optic tunable filter (AOTF) as well as its responsivity to the rf driving signal and sensitivity to temperature changes are experimentally investigated and quantified using a diode-laser-based interrogation system. A spectroscopic technique, exploiting the rf frequency modulation of the laser beam and the phase-sensitive detection of the AOTF transmission, has been used for this purpose. That allows for the generation of a dispersivelike signal, which serves as a reference for tracking any wavelength change of the filter's peak with high resolution. The possibility of using the integrated AOTF as a spectrum analyzer with this interrogation scheme for fiber Bragg grating (FBG) strain sensing is also discussed.
Di Maio
Antonio
A
CNR-Istituto Nazionale di Ottica Applicata and European Laboratory for Non-Linear Spectroscopy, Naples, Itlay.
Salza
Mario
M
Gagliardi
Gianluca
G
Ferraro
Pietro
P
De Natale
Paolo
P