Abstract:
A method of writing a photo-induced structure into a photosensitive material substrate, the method comprising the steps of creating an interference pattern utilising at least two light beams, exposing the substrate to the interference pattern for photo-inducing material changes in the substrate, and creating an irregularity in the interference pattern by controlling a wavefront of at least one of the beams, for creating a functional defect in the photo-induced structure.
Abstract:
A laser arrangement comprising a ring cavity at least two gain portions in said ring cavity, an input-output coupling connected to said ring cavity, a discriminator means connected in said ring cavity and adapted to discriminate between a pumping signal and an output signal and pumping means for providing said pumping signal and connected to said gain portions of said ring cavity such that, upon activation of said pumping means, said laser arrangement operates as a laser producing a laser output at said input-output coupling.
Abstract:
A method of writing a photo-induced structure into a photosensitive material substrate, the method comprising the steps of creating an interference patte rn utilising at least two light beams, exposing the substrate to the interferen ce pattern for photo-inducing material changes in the substrate, and creating a n irregularity in the interference pattern by controlling a wavefront of at least one of the beams, for creating a functional defect in the photo-induce d structure.
Abstract:
The present invention provides an optical device incorporating a sampled grating structure having a chirped sampling period. The present invention ma y alternatively be defined as a method of producing a grating structure in a photosensitive optical waveguide, the method comprising the step of irradiating the device with UV light at an intensity sufficient to induce refractive index variations in the waveguide in a manner to produce a sample d grating structure, and wherein the radiation is controlled in a manner to effect chirping of the sampling period. The invention may alternatively be defined as providing a group delay dispersion compensator device comprising a sampled grating structure a having chirped sampling period. It has also been recognised that a method of producing a zero dispersion WDM channel can be provided.