ALEXANDRIA, Va., March 3 -- United States Patent no. 12,565,445, issued on March 3, was assigned to OHARA Inc. (Kanagawa, Japan).
"Optical filter glass ceramic and optical filter" was invented by Toshitaka Yagi (Kanagawa, Japan) and Saya Kikkawa (Kanagawa, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A glass ceramic for an optical filter and an optical filter are obtained that have both thermal expansion characteristics for preventing refractive index fluctuations at a usage temperature of a filter member and mechanical characteristics considering durability, and further have excellent workability. An internal transmittance of the glass ceramic for an optical filter is 0.970 or more with respect to l...