ALEXANDRIA, Va., July 30 -- United States Patent no. 12,374,851, issued on July 29, was assigned to NEC Corp. (Tokyo).

"Optical amplification apparatus and optical amplification method" was invented by Hitoshi Takeshita (Tokyo), Keiichi Matsumoto (Tokyo) and Emmanuel Le Taillandier De Gabory (Tokyo).

According to the abstract* released by the U.S. Patent & Trademark Office: "An optical amplification apparatus includes an optical amplification medium, having a gain in a wavelength band of signal light, configured to receive the signal light; excitation light introduction means for introducing, into the optical amplification medium, excitation light to excite the optical amplification medium; and residual excitation light introduction means...