Patent ID: 6865320
Filing Date: 2005-03-08
Classification: G01J,G02B

Abstract:
1. A polarization insensitive optical tap formed in a section of optical waveguide including a core region for supporting the propagation of an optical signal, said polarization-insensitive optical tap comprising: a first highly-tilted grating disposed along a predetermined portion of the core region of the section of optical waveguide, said first highly-tilted grating oriented to out-couple a first optical signal from a propagating optical signal at a predetermined angle with respect to the optical axis of the optical waveguide; a second highly-tilted grating disposed in association with said first highly-tilted grating along said predetermined portion of said core region of said section of optical waveguide, said second grating tilted at essentially the same angle as said first highly-tilted grating and oriented to out-couple a second optical signal from said propagating optical signal at an angle orthogonal to said predetermined angle, said second optical signal exhibiting a polarization state orthogonal to the polarization state of the first optical signal; and an optical detector disposed outside of the section of optical waveguide at a location to capture the first and second optical signals from the first and second highly-tilted gratings, said optical detector for summing the pair of output signals to remove polarization dependence and provide an optical monitoring signal output.