GT Solar International, Inc. (NASDAQ: SOLR), a global provider of polysilicon production technology, and sapphire and silicon crystalline growth systems and materials for the solar, LED and other specialty markets, today announced that its subsidiary, GT Crystal Systems LLC, has signed a multi-year contract valued at $3.75 million with Exotic Electro-Optics, Inc., (EEO), a subsidiary of II-VI Incorporated (NASDAQ: IIVI). Under the terms of the contract, GT Crystal Systems will provide large sapphire blanks to EEO for a US-based defense program. The sapphire material will be produced in GT’s recently expanded, state-of-the-art manufacturing facility located in Salem, Massachusetts.

“The optical performance of the sapphire material is critical to meeting the demanding requirements for this program,” said Andrew Riser, General Manager of Exotic Electro-Optics. “GT Crystal Systems has proven over the years that they can deliver the high quality sapphire material we need to engineer precision optical solutions and meet our cost requirements as well.”

“We are pleased that Exotic Electro-Optics has selected GT Crystal Systems and we look forward to continuing our relationship in the years to come,” said Cheryl Diuguid, vice president and general manager of GT Solar’s sapphire material and equipment business unit. “Our ASF-grown sapphire material is recognized worldwide for its high quality optical performance that can support the most stringent applications. The scalability of our ASF crystal growth technology allows us to produce sapphire material capable of meeting the large diameters required for this program.”

EEO is a leading supplier of state-of-the-art infrared optics, coatings and assemblies for aerospace, defense, and commercial markets. They will utilize the large 13-inch sapphire blanks to fabricate high performance sapphire windows for a multi-spectral aerospace application. The sapphire blanks contain high quality sapphire material which exhibits uniform crystalline structure without visible inclusions. Delivery of the material began in June of this year.