Optical isolator, attenuator, circulator and switch

Abstract

A polarization independent optical isolator, attenuator, circulator and switch include at least a combination of birefringent prisms with parallel optic axes for dividing an input beam into parallel polarized beams or for combining parallels polarized beams into an output beam. In particular, an optical isolator ( 8 ) includes a first combination of birefingent prisms ( 10, 11 ), Farady rotator ( 12 ), half waveplate ( 13 ) and a second combination of birefringent prisms ( 14, 15 ). Devices may be conservative in the use of birefringent material, high in isolation and free from polarization mode dispersion.

1 . A device such as an optical isolator, attenuator, circulator or switch including a combination of birefringent prisms with parallel optic axes capable of dividing an input beam into polarized beams and combining polarized beams into an output beam.  
     
     
         2 . (canceled)  
     
     
         3 . A device such as an optical isolator, attenuator, circulator or switch including a combination of birefringent prisms with parallel optic axes capable of dividing an input beam into parallel polarized beams and combining parallel polarized beams into an output beam.  
     
     
         4 . (canceled)  
     
     
         5 . A device of  claim 1  further comprising a second combination of birefringent prisms with parallel optic axes for combining parallel polarized beams into an output beam, and a polarization changer disposed between said first combination of birefringent prisms and said second combination of birefringent prisms.  
     
     
         6 . A device of  claim 3  further comprising a second combination of birefringent prisms with parallel optic axes for combining parallel polarized beams into an output beam, a polarization changer disposed between said first combination of birefringent prisms and said second combination of birefringent prisms, and a third combination of birefringent prisms with parallel optic axes disposed between said polarization changer and said second combination of birefringent prisms.  
     
     
         7 . An optical device as described in  claim 1 , wherein prisms of at least one combination of birefringent prisms are arranged about at least one reflector or refractor.  
     
     
         8 . An optical device as described in  claim 1 , wherein prisms of at least one combination of birefringent prisms are arranged about a polarization changer.  
     
     
         9 . An optical isolator as described in  claim 5 , wherein at least one polarization changer is a nonreciprocal polarization changer.  
     
     
         10 . An optical attenuator as described  claim 5 , wherein at least one polarization changer is a reciprocal polarization changer.  
     
     
         11 . An optical circulator as described in  claim 5 , wherein at least one polarization changer is a nonreciprocal polarization changer.  
     
     
         12 . An optical switch as described in  claim 5 , wherein at least one polarization changer is a reciprocal polarization changer.