Corning Diamond Turning Div. of Keene, N.H., has received its third contract upgrade from DRS Optronics of Palm Bay, Fla., for the supply of optical assemblies used in the Long Range Advanced Scouting Surveillance System program. Each assembly comprises several fold mirrors, a three-mirror anastigmat telescope and a laser beam expander, all of which are reflective. Valued at $1.7 million, the contract will raise the total number of deliverable systems to more than 650 units.