Patent ID: 9634457
Date: 2017-04-25
CPC Classifications: G02B,G02F,H01S

Claim:
1. A source of optical supercontinuum radiation, the source comprising: a length of microstructured optical fibre; a pump laser adapted to generate lasing radiation at a pump wavelength; said length of microstructured optical fibre arranged for receiving lasing radiation at the pump wavelength so as to generate optical supercontinuum radiation, said microstructured optical fibre comprising a core region and a cladding region which surrounds the core region; wherein said source of optical supercontinuum radiation is arranged such that at a location along the length of microstructured optical fibre: (a) said microstructured optical fibre comprises a group index (GI) versus wavelength curve having a zero crossing wavelength (ZCW) at which the group velocity dispersion has a zero crossing and such that the GI increases for wavelengths away from the ZCW such that the curve includes group indices that are greater than the GI at the ZCW for wavelengths greater than as well as less than the ZCW; (b) light having a wavelength of greater than 2000 nm is propagating along the length of microstructured optical fibre and has a GI that is matched to the GI of light that is propagating along the length of microstructured optical fibre and that has a wavelength of less than 400 nm; and (c) the pump wavelength is within 200 nm of the ZCW.