Patent Number: 6,310,996

Title: Writing Bragg gratings in optical waveguides

Abstract: Instead of a single beam, two coherent beams of light are used to illuminate a phase grating in spatially separated zones for writing a Bragg reflection grating in an underlying optical (fiber) waveguide. Close proximity between phase mask and waveguide is not required. This facilitates the use of masking so that only two different diffracted orders contribute to the fringe pattern that generates the Bragg grating, thereby improving fringe contrast and reducing the deleterious spectral effects upon the reflectivity of the Bragg reflector occasioned by the presence of stitch errors in the phase grating.

Inventors: Byron; Kevin Christopher (Herts, GB)

Assignee: Nortel Networks Limited

International Classification: G03F 7/20 (20060101); G02B 006/34 ()

Expiration Date: 10/30/2018