US Patent Issued to NIKON on May 12 for "Calcium fluoride polycrystalline substance, production method of calcium fluoride particle, production method of calcium fluoride polycrystalline substance, optical element, optical system, interchangeable lens and optical device" (Japanese Inventors)

ALEXANDRIA, Va., May 12 -- United States Patent no. 12,625,299, issued on May 12, was assigned to NIKON Corp. (Tokyo).

"Calcium fluoride polycrystalline substance, production method of calcium fluoride particle, production method of calcium fluoride polycrystalline substance, optical element, optical system, interchangeable lens and optical device" was invented by Mariko Hirayama (Tokyo), Hitoshi Ishizawa (Kawasaki, Japan), Takuro Nakamura (Yamato, Japan), Yoshinobu Ezura (Yokohama, Japan) and Yuya Yamamoto (Machida, Japan).

According to the abstract* released by the U.S. Patent & Trademark Office: "A calcium fluoride polycrystalline substance, in which the internal transmittance of light having a wavelength of 550 nm per thickness of 10 ...