ALEXANDRIA, Va., March 24 -- United States Patent no. 12,586,973, issued on March 24, was assigned to NTT Inc. (Tokyo).
"Rare earth doped fiber and fiber optic amplifier" was invented by Yoko Yamashita (Tokyo), Kazuhide Nakajima (Tokyo) and Takashi Matsui (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "An object of the present disclosure is to allow gain compensation with a simple configuration without adding a new device to the outside. The present disclosure discloses a rare earth doped fiber including a core doped with a rare earth and a cladding region around the core, wherein one or more cavities are provided inside the core, and at least one of the cavities are provided along a longitudinal direc...