Optical Grade Sapphire Manufacturing Growth Process for IR Window Applications

Sapphire possesses a number of physical properties, including high strength, high melting point, chemical inertness, and excellent transparency in the visible and IR spectrum, which make it an attractive window material for military applications. Until recently, the largest detrimental factor has been the small size of available crystals. However, crystal growth capabilities have advanced to where large, single crystal sapphire windows are now realizable. During Phase I, Rubicon Technology, with their extensive experience in bulk sapphire crystal growth, will investigate the feasibility of producing optical grade sapphire blanks for use as IR windows. Research efforts will focus on designing and demonstrating a horizontal furnace capable of producing sapphire windows with minimum post-processing dimensions of 14” x 20” x 1”. BENEFIT: The ability to provide c-plane sapphire will address new markets where application are currently not serviceable by current sapphire products due to limitations in window size and thickness and/or concerns over strength or optical quality of the material. Some specific target markets include commercial aircraft and commercial shipping which will benefit from the enhanced optical qualities as well as enhanced strength of the c-plane material. In addition, many applications for clear armor currently rely on less effective materials that could be improved by utilizing sapphire windows.