Arrayed waveguide grating with waveguides of unequal widths

Abstract

The present invention provides an arrayed waveguide such that each waveguide of the grating has a substantially uniform width, but the width of any single waveguide in the grating is selected based on a predetermined birefringence required for the waveguide. Generally, the narrowest grating waveguide has the longest overall length and the widest grating waveguide has the shortest overall length. The remaining intermediate waveguides have widths that are interpolated between the narrowest and widest waveguide gratings. With an appropriate width for each waveguide, an arrayed waveguide grating is provided that has low polarization dependent wavelength.

1 - 32 . (canceled)  
   
   
       33 . A method of providing a predetermined polarization dependent wavelength in an optical device comprising: 
 transmitting light into a first waveguide having a first width and a length;    transmitting the light into at least a second waveguide having a second narrower width and a longer length.    
   
   
       34 . The method of  claim 33  further comprising transmitting the light into a plurality of additional waveguides, wherein each of the additional subsequent waveguides has an increasing length and a corresponding decreasing width.  
   
   
       35 . The method of  claim 33  wherein the light is transmitted into the first and the second waveguides simultaneously.  
   
   
       36 . The method of  claim 33  wherein the light is transmitted into the first waveguide before the second waveguide.  
   
   
       37 . The method of  claim 33  wherein the light is transmitted into the second waveguide before the first waveguide.