Patent ID: 7068431
Filing Date: 2006-06-27
Classification: B82Y,G02B,G02F

Abstract:
1. An optical device comprising: a photonic crystal designed to have a shape of a dispersion surface with a strong direction dependence at a frequency; light input means configured to allow a light beam having a wavelength determined by said frequency to be incident on said photonic crystal at an incident angle determined from a region with a large change of direction dependence in the shape of the dispersion surface according to the law of conservation of momentum; and a deflection controller configured to apply an energy to said photonic crystal in order to switch between a first optical path for allowing the light beam incident on said photonic crystal to pass through said photonic crystal, thereby obtaining a first transmitted light beam, and a second optical path, which is angularly different from said first optical path, for allowing the light beam incident on said photonic crystal to pass through said photonic crystal, thereby obtaining a second transmitted light beam.