Accelerated Development of Edge Bonded ALON Reconnaissance (Recce) Windows

Requirements for future reconnaissance (Recce) systems are driving the need for very large (~32"x32"), very high quality windows transparent in the visible and Mid Wave Infrared (MWIR) wavebands. At the present time, the leading candidate material for these demanding Recce applications is ALON Optical Ceramic, produced by Surmet Corp. The current available production equipment is limited to fabricating high quality ALON window blanks as large as ~17"x30". Nearly doubling the 17"width to produce a monolithic ALON window 32"wide would require significant capital investment. Alternatively, during the Phase I effort, Surmet demonstrated edge bonding techniques which allow two smaller windows to be fused together to produce a large window which can be optically fabricated as a single part. The bonding techniques have produced transparent bonds with strengths approaching that of the ALON material itself. In the Phase II effort, Surmet proposes to refine these techniques, select the most promising one and then scale it to produce 12", then 20"and finally 32"long seams. The program will culminate with the bonding of a nominally 32"x32"ALON window blank and its subsequent optical fabrication and characterization. BENEFIT: Successful completion of this program will result in a fabrication of large optically transparent ceramics for reconnaissance applications. The commercial opportunity for this technology will extend to the fabrication of very large sensor windows, transparent armor windows, and windows for other specific applications. Strong transparent bonds capable of withstanding high temperatures will serve the needs for application in chemical processing equipment, etc.