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:
Aug. 04, 2009
Filed:
Dec. 07, 2006
John D. Minelly, Bothell, WA (US);
Anping Liu, Big Flats, NY (US);
John D. Minelly, Bothell, WA (US);
Anping Liu, Big Flats, NY (US);
Lockheed Martin Corporation, Bethesda, MD (US);
Abstract
A method and apparatus using a gain medium in the form of a multiply clad gain fiber having an erbium-doped core. In some embodiments, aluminum and germanium are added to the silica core to make λlonger than the signal wavelength so the signal incurs normal dispersion. Optionally, a large-mode-area core amplifies primarily only one low-order mode because its NA is reduced by lowering the core's index of refraction (e.g., by adding fluorine) and/or by raising the index of the silica inner core (e.g., by adding germanium). Optionally, a thulium-doped region provides substantial loss at the first Raman-gain peak with respect to the signal wavelength but minimal loss at the signal or pump wavelength. Optionally, an inner cladding with a higher NA contains pump light within the outer boundaries of the cladding while allowing pump light to enter the core. In some embodiments, a triple cladding is provided.