Design Model for Low Crosstalk Acousto-Optic Tunable Filters

One of the major issues in designing Acousto-optic tunable filters (AOTF) for optical networks remains the reduction of interchannel crosstalk, one significant source of which is the sidelobes in the typical sine-squared transmission passband of the device. Interchannel crosstalk reduction can be achieved by sidelobe suppression, as has been experimentally demonstrated using two different techniques: (i) employing apodization of the acousto-optic interaction strength by means of acoustic wave couplers [1]; or (ii) by using focused surface acoustic waves [2].