Patent ID: 6163552
Filing Date: 2000-12-19
Classification: H01S

Abstract:
An article comprising a cascaded Raman resonator comprising a length of silica-based single mode optical fiber with a first multiplicity of upstream refractive index gratings and a second multiplicity of downstream refractive index gratings spaced from, said upstream refractive index gratings, with each refractive index grating having a center wavelength and a reflectivity at the center wavelength, the cascaded Raman resonator being adapted for receiving pump radiation of wavelength .lambda..sub.p at a location upstream of said first multiplicity of upstream refractive index of g/ratings, and furthermore adapted for providing, at a location downstream of said second multiplicity of downstream refractive index gratings, output radiation of wavelength.lambda..sub.s,1 >.lambda..sub.p ;Characterized in thata) the cascaded Raman resonator is a multi-wavelength cascaded Raman resonator adapted for providing, at the location downstream of the second multiplicity of downstream refractive index gratings, at least one further output radiation of wavelength .lambda..sub.s,2 >.lambda..sub.p ;b) the first multiplicity of upstream refractive index gratings comprises a first and a second refractive index grating, and the second multiplicity of downstream refractive index gratings comprises a third and a fourth refractive index grating, with said first and third refractive index gratings having center wavelength essentially equal to .lambda..sub.s,1, and said second and fourth refractive index gratings having center wavelength essentially equal to .lambda..sub.s,2 ; andc) said first refractive index grating has a reflectivity at the center wavelength .lambda..sub.s,1 that is greater than the reflectivity of the third refractive index grating at the center wavelength .lambda..sub.s,1, and said second refractive index grating has a reflectivity at the center wavelength .lambda..sub.s,2 that is greater than the reflectivity of the fourth refractive index grating at the center wavelength .lambda..sub.s,2.