Tunable optical filter for wavelength-division multiaccess computer network

A novel tunable optical filter with a tuning speed of 2 μs, a tuning range of approximately 60 nm at 1.55 μm, and a resolution of 0.5 angstrom (6.3 GHz) has been proposed and demonstrated for application in wavelength division multiaccess computer network. The principle of operation is by positioning an optical beam emitting from an optical fiber that carries all wavelengths onto two crossed wedge etalons. Depending on the location of the optical beam incident on the etalon assembly, only a certain wavelength that matches the thickness of the etalons at that location is transmitted. The optical beam positioning is achieved by two single-axis acousto-optical deflectors. The number of channels supported by the filter is estimated to be approximately 600.