Patent ID: 6560386
Filing Date: 2003-05-06
Classification: G02F

Abstract:
A method of segregating a desired wavelength from a multiple wavelength light signal, the method comprising the steps of:providing an optical signal device comprising: a) a substrate, b) a pair of first and second spaced apart cladding layers, c) a core layer including a waveguide or a pair of opposed waveguides positioned between the pair of cladding layers having a refractive index greater than the refractive indices of the first and second cladding layers such that the difference between the refractive indices of the core layer and the cladding layers enables the multiple wavelength light signal to pass through the device in a single mode, d) a grating region present in each of the cladding layers and the core layer, the grating forming a filter element, the filter element being configured to cause a single wavelength of light of the multiple wavelength light signal to be segregated therefrom, and e) a tuning apparatus for varying the refractive index of at least the core layer to thereby control the wavelength of the light which is to be segregated from the multiple wavelength light signal; passing the multiple wavelength light signal through the optical signal device; and tuning the tuning apparatus to segregate the desired wavelength from the multiple wavelength light signal.