Patent ID: 7704644

Claim:
A process for fabricating a three-dimensional photonic crystal, the process comprising: providing a grating array having first, second and third sets of diffraction gratings wherein said grating array is secured on a mask plate which separates the grating array from a layer of photosensitive material; introducing a first plurality of laser beams into the photosensitive material through a first set of said diffraction gratings during a first exposure wherein the first plurality of laser beams comprises providing a singular beam directed at the first set of diffraction gratings while blocking the second and third sets of diffraction gratings with a beam-blocking shutter; moving the beam-blocking shutter to expose the second set of diffraction gratings and cover the first and third sets of diffraction gratings; introducing a second plurality of laser beams into the photosensitive material through the second set of diffraction gratings during a second exposure different from the first exposure wherein the second plurality of laser beams comprises providing a singular beam directed at the second set of diffraction gratings while blocking the first and third sets of diffraction gratings with the beam-blocking shutter; moving the beam-blocking shutter to expose the third set of diffraction gratings and cover the first and second sets of diffraction gratings; introducing a third plurality of laser beams into the photosensitive material through the third set of said diffraction gratings during a third exposure different from the first and second exposures wherein the third plurality of laser beams comprises providing a singular beam directed at the third set of diffraction gratings while blocking the first and second sets of diffraction gratings with the beam-blocking shutter; and combining results from at least the first, second, and third exposures to produce a three-dimensionally periodic pattern in the photosensitive material.