Patent ID: 8320032
Filing Date: 2012-11-27
Classification: G02B

Abstract:
1. A device comprising: a substantially planar waveguiding substrate; an input grating to provide an in-coupled beam propagating within said substrate by diffracting light of an input beam into said substrate; a first deflecting grating portion to provide a first deflected beam by diffracting a part of said in-coupled beam such that the difference between the azimuth angle of said first deflected beam and the azimuth angle of said in-coupled beam is negative, said first deflecting grating portion comprising substantially linear diffractive features; a second deflecting grating portion to provide a second deflected beam by diffracting a part of said in-coupled beam such that the difference between the azimuth angle of said second deflected beam and the azimuth angle of said in-coupled beam is positive, said second deflecting grating portion comprising substantially linear diffractive features, the diffractive features of said second deflecting grating portion having a different orientation than the diffractive features of said first deflecting grating portion; a first restoring grating portion to provide a first restored beam by diffracting light of said first deflected beam; a second restoring grating portion to provide a second restored beam, said second restored beam being substantially parallel to said first restored beam; and an output grating, wherein a part of the in-coupled beam propagates within the substrate without being diffracted by said first deflecting grating portion, said second deflecting grating portion, said first restoring grating portion and said second restoring grating portion to provide a non-diffracted beam, and said output grating to provide an out-coupled beam by diffracting light of said first restored beam, said non-diffracted beam and said second restored beam out of said substrate, said out-coupled beam being substantially parallel to said input beam.