US Patent Issued to NTT on March 3 for "Optical device" (Japanese Inventors)

ALEXANDRIA, Va., March 3 -- United States Patent no. 12,566,294, issued on March 3, was assigned to NTT INC. (Tokyo).

"Optical device" was invented by Takuma Tsurugaya (Tokyo), Shinji Matsuo (Tokyo), Koji Takeda (Tokyo) and Takuro Fujii (Tokyo).

According to the abstract* released by the U.S. Patent & Trademark Office: "A difference triangle1 between an equivalent refractive index of a first reflecting section and an equivalent refractive index of a core in a first region that corresponds to the first reflecting section and a difference between an equivalent refractive index of a second reflecting section and an equivalent refractive index of the core in a second region that corresponds to the second reflecting section is set so as to be ...