Patent ID: 7324179

Claim:
A reflector comprising: a predetermined plane; a plurality of unit reflecting portions disposed parallel to said predetermined plane, wherein at least one of said plurality of unit reflecting portions has a reflection face configured to reflect incident light in a different direction from regular reflection light of said predetermined plane; a first reflection face arranged in a first unit reflecting portion comprising a first tangential plane tangent to the first reflection face at a reference point on the first reflection face; and a second reflection face arranged in a second unit reflecting portion adjacent to said first unit reflecting portion comprising a second tangential plane parallel to said first tangential plane and tangent to the second reflection face, wherein the reference point is selected from a portion of the first reflection face that dominates a light intensity from the first reflection face, and wherein a shortest distance between the reference point and the second tangential plane is between half of a coherent length of the incident light and 20 μm.