title: Measurements of the thermal expansion of six optical materials, from room temperature to 250 degrees C.
abstract: Coefficients of linear thermal expansion are reported in the range from room temperature to 250 degrees C for six optical materials: Polytran potassium chloride and Polytran calcium fluoride-Harshaw; chemical-vapordeposited (CVD) zinc selenide and zinc sulfide-Raytheon; single-crystal germanium-Eagle-Picher; and lithium niobate-Harshaw. For the last named, an anisotropic crystal, thermal expansion was measured both parallel and perpendicular to the c axis. Curves are given to illustrate the expansion behavior of the materials over the 60-500-K range.
authors.forename: S S
authors.initials: SS
authors.lastname: Ballard
authors.forename: S E
authors.initials: SE
authors.lastname: Brown
authors.forename: J S
authors.initials: JS
authors.lastname: Browder