STRUCTURE OF OPTICAL WAVEGUIDE HAVING BRAGG DIFFRACTION GRATING PROVIDED THEREIN FOR CHANGING OPTICAL DIRECTION

摘要

PURPOSE: To sufficiently couple light to the inside and outside of an optical waveguide in a device for changing the propagation direction of the light inside the optical waveguide. CONSTITUTION: This constitution for changing the propagation direction of the light inside the optical waveguide is provided with the optical waveguide 10 provided with a solid part for guiding the light inside a first route along an axis in a vertical direction and at least one diffraction grating area 13 is buried inside the solid part present at a position away from an end part. The diffraction grating area 13 is provided with many diffraction grating elements 14 and the elements are spread at equal intervals practically vertically at an angle inclined relating to a vertical axis so as to change the propagation direction of the light reaching the diffraction grating element 14 between the first route and at least one of second routes extended to the outside of a waveguide part at the angle related to the vertical axis by an inclination angle.