Infrared transparent optical element and infrared imaging camera using the same

摘要

An infrared transparent optical element of the invention is for use as an optical window for an infrared imaging camera. The optical element includes an infrared transparent substrate, an antireflection film, and a protective film made of a polymer material. The infrared transparent substrate has first and second major surfaces opposite to each other, and the antireflection film is formed on each of the first and second major surfaces of the substrate. The protective film is formed on an outer surface of the antireflection film on the first major surface of the substrate.