New and improved non-radioactive coated lens for use in laser transmissions are created by vacuum deposition of specially prepared particles formed by melting 10-20% (w/w) barium fluoride and 90-80% (w/w) cerium fluoride in an inert atmosphere to form a mass which when cooled is comminuted into small...http://www.google.se/patents/US5262196?utm_source=gb-gplus-sharePatent US5262196 - Methods of producing improved optical coatings
