Patent ID: 6501895
Filing Date: 2002-12-31
Classification: G02B

Abstract:
Optical device with a defined total device stress (&sgr;10) and a therefrom resulting defined birefringence in order to obtain a well defined optical polarization dependence, comprising:a) a lower cladding layer having a first refractive index (n3), b) on said lower cladding layer an upper cladding layer having a second refractive index (n5), c) between said lower cladding layer and said upper cladding layer an optical waveguide core having a third refractive index (n4) which is bigger than said first refractive index (n3) and said second refractive index (n5), d) said optical waveguide core having a waveguide core stress (&sgr;4) resulting from the manufacturing process for said waveguide core, said manufacturing process comprising an annealing process, which preferably serves the extraction of hydrogen from the waveguide core. e) wherein said upper cladding layer comprises material which is tuned to a selected cladding layer stress (&sgr;5) by variation of annealing temperature in an annealing process during manufacturing, said cladding layer stress (&sgr;5) together with said waveguide core stress (&sgr;4) resulting in said total device stress (&sgr;10).