Active element added-optical fiber, resonator, and fiber laser device
AssigneeFujikura Ltd.
InventorsRyoichi Nishimura, Rintaro Kitahara
Life of this patent
Estimating the term…
Abstract
An active element-doped optical fiber includes: a core that includes first and second regions. The first region ranges from a central axis to a predetermined radius, and is doped with an active element excited by excitation light. The second region surrounds the first region with no gap, extends to an outer peripheral surface of the core, and is not doped with the active element. The core satisfies 0.1 d<ra<d, where ra is a radius of the first region and d is a radius of the core. The core has, in a region of 0.2 d<r≤0.9 d, a maximum value position at which a refractive index becomes maximum, where r is a distance from a central axis of the core in a radial direction.
Claims24
An active element-doped optical fiber comprising:
- a core that includes a first region and a second region, wherein
- the first region ranges from a central axis to a radius of the first region, and is doped with an active element excited by light,
- the second region surrounds the first region with no gap, extends to an outer peripheral surface of the core, and is not doped with the active element,
- the core satisfies 0.1 d<ra<d, where ra is the radius of the first region and d is a radius of the core, and
- the core has, in a region of 0.2 d<r≤0.9 d, a maximum value position at which a refractive index becomes maximum and higher than an average value of a refractive index in a region of 0≤r≤0.9 d, where r is a distance from a central axis of the core in a radial direction.
Dependencies are inferred from the claim text.