Demonstration of a fibre-optic tapped delay line spectrometer

A method for obtaining power spectral estimates for narrow-band (<100 MHz) optical signals is reported, based on measurements of the far-field intensity profiles resulting from diffraction of the output of a fiber optic tapped delay line array. The device exhibits a resolving power exceeding 10/sup 7/, as well as an angular dispersion of 0.4/spl deg//GHz, representing an improvement of at least three orders of magnitude over conventional diffraction gratings.<
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