Patent ID: 6031957
Filing Date: 2000-02-29
Classification: G02B,G02F

Abstract:
A glass wave guide element comprising a substrate; an under cladding formed on said substrate; a core having a diffraction grating with a spatially periodically changing refractive index along a light transmission direction, said core being formed on said under cladding; an over cladding covering said core; and a heater for changing the Bragg wavelength of said diffraction grating, said heater being arranged in said over cladding, whereinsaid core and a central portion of both said claddings in a surrounding portion around said core are formed in a state being continuously separated along a longitudinal direction of said core from said substrate through a gap, and said core and said surrounding portion around said core are formed in a state separated in a width direction of said core from a surrounding portion of both said claddings through a gap.