Ultrahigh -47-dB optical drop rejection multiwavelength add-drop filter using spatial filtering and dual bulk acousto-optic tunable filters

A new high-speed, ultrahigh cross-talk-suppression multiwavelength add-drop optical filter structure is demonstrated with two bulk acousto-optic tunable filters. With simple spatial blocks, an average -47-dB optical suppression is measured for the unwanted wavelengths at the filter output ports. The filter is tested for the three standard visible wavelengths, red, green, and blue, and demonstrates a switching time of 0.65 μs and an average optical loss of 5 dB. Applications for this filter include multiwavelength switching applications such as wavelength-division-multiplexed optical communications.