A polarization independent acousto-optical tunable filter (AOTF). The AOTF is fabricate with two waveguides [33] [35] formed on a single substrate [31]. An incoming polarization independent beam of light is split into TE and TM optical components with a walk-off crystal [37] wherein each optical component is coupled into a different one of the two waveguides [33] [35]. The AOTF can be formed to provide two stages of filtering. The two stages of filtering can be realized be providing two successive stages or by passing the optical signal through the same filter twice. Various configurations are obtained by placing TM and TE polarizers within the optical path traveled by the incoming beam of light.
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