The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 03, 2011
Filed:
May. 11, 2007
Michael Kevan Durkin, Southampton, GB;
Stephen Roy Norman, Romsey, GB;
Fabio Ghiringhelli, Southampton, GB;
David Neil Payne, Southampton, GB;
Louise Mary Brendan Hickey, Windsor, GB;
Jayanta Kumar Sahu, Southampton, GB;
Mikhail Nickolaos Zervas, Southampton, GB;
Andy Piper, Southampton, GB;
Andrew Michael Gillooly, Southampton, GB;
Michael Kevan Durkin, Southampton, GB;
Stephen Roy Norman, Romsey, GB;
Fabio Ghiringhelli, Southampton, GB;
David Neil Payne, Southampton, GB;
Louise Mary Brendan Hickey, Windsor, GB;
Jayanta Kumar Sahu, Southampton, GB;
Mikhail Nickolaos Zervas, Southampton, GB;
Andy Piper, Southampton, GB;
Andrew Michael Gillooly, Southampton, GB;
SPI Lasers UK Ltd, Southampton, GB;
Abstract
In one embodiment, a photo-darkening resistant optical fiber includes a waveguide having a numerical aperture less than 0.15. The waveguide includes a core having a refractive index nand a pedestal having a refractive index n, and wherein the fiber includes a first cladding having a refractive index nsurrounding the pedestal, wherein nis greater than n, nis greater than n. The core includes silica, a concentration of alumina of between approximately 0.3 to 0.8 mole percent, a concentration of phosphate of substantially 15 mole percent, a concentration of ytterbium substantially in the range 20000 to 45000 ppm. The pedestal can include silica, phosphate and germania. The core can have substantially zero thulium dopant.