Patent ID: 6904200

Claim:
An optical interference grating, comprising: a background region of a first material having a first refractive index; a grid of cells within said background region wherein said cells are of a second material having a second refractive index; a plurality of said cells each having at least one incident surface; said plurality of said cells also each having opposed surfaces, respective to said incident surfaces; said incident surfaces are pitched such that, when the optical interference grating receives a light beam, first portions thereof may strike said incident surfaces, enter said cell, travel to said opposed surfaces, be reflected there from, travel back to said incident surfaces, and exit said cell as refracted beams; and said arid of cells is optically two-dimensional by virtue of said cells having at least two of cell-to-cell and surface-to-surface optical separations such that said reflected beams will constructively interfere for a predetermined light wavelength when it is present in said light beam.