SEI is no accident.

Established in 1991 SEI is recognized as a leader in the wholesale distribution of rare earth inorganic optical coating materials. SEI is famous for its SiO2, MgF2 and ZnS along with a complete line of oxides and fluorides covering the U.V., visible and I.R. regions. SEI customers include some of the worlds largest Laser, Fiber-Optic and Astronomy companies. Superior Evaporants Incorporated exists because there is the need for an
optical coating material company that is committed not only to superior product quality, but also comprehensive service, technical assistance, and price. By carefully selecting a team of administrative and technical support, by researching sources worldwide for impeccable product quality, and by listening carefully to our customers, SEI has built a company famous for its quality, service and value.

SEI has exactly what you need.

After negotiating both national and culteral boundaries SEI has secured more than 30 of the finest evaporation chemicals available. Most exceed current industry standards for purity. SEI has introduced three materials that are made from crushed single crystal boules. These are Zinc Sulfide (ZnS), Magnesium Fluoride (MgF2) and Barium Fluoride (BaF2). The optical characteristics of the films produced by these three materials are simply excellent.