ALEXANDRIA, Va., July 3 -- United States Patent no. 12,348,846, issued on July 1, was assigned to The Boeing Co. (Arlington, Va.).

"Method and apparatus for extending operational availability for terrestrial optical surveillance systems" was invented by Richard B. Holmes (Albuquerque, N.M.) and Steven F. Griffin (Kihei, Hawaii).

According to the abstract* released by the U.S. Patent & Trademark Office: "A retrofittable subassembly that enhances the operational availability of a terrestrial optical surveillance system is disclosed. In various embodiments, the subassembly comprises a diffusely reflective and insulating external cover, a highly uniform plate-glass cover, an wide angle FOV camera and a passive thermal control system."

The pa...