By Kari Williamson

The team, which includes the University of Rochester and Ed White Consultants, will establish a production capability for the M-GRIN lenses from Surmet's ALON optical ceramic. ALON GRIN lenses are said to hold the promise of higher Vis-MWIR performance at reduced size, weight and cost.

During the M-GRIN programme’s first phase, Surmet demonstrated the ability to create ALON GRIN lens blanks with axial gradients. During Phase II Surmet will develop the ability to extend the magnitude and spatial extent of these gradients, using processes compatible with large volume manufacturing.

The University of Rochester will develop the metrology used to characterise the ALON GRIN lens blanks and lenses produced during the programme. The university will also lead the design effort to exploit the advantages of ALON M-GRIN lenses for advanced Department of Defense (DoD) optical systems.

Ed White Consultants will guide the manufacturing readiness assessment of the MGRIN technology.

Surmet will also include DoD prime contractors in the program to facilitate the transition of the ALON M-GRIN technology into military systems.

ALON ceramic

Current applications for ALON optical components exploit its combination of broadband transparency (UV-MWIR) with good physical, mechanical and chemical properties. ALON Transparent Armor can stop armour piercing projectiles at half the weight and half the thickness of conventional glass armour, while providing 50% higher transmission for night vision goggles, Surmet says.

ALON windows and domes are being used in military systems for tracking, imaging and reconnaissance. ALON is also being evaluated for semiconductor processing and energy related applications because of its high dielectric breakdown strength and excellent chemical resistance.

Its cubic structure means that ALON is transparent in its polycrystalline form. This means that ALON Optical Ceramic can be produced using conventional powder ceramic processing techniques.

ALON powder is consolidated into a green body using any one of a number of forming techniques including cold isostatic pressing, slip casting and injection moulding, before being brought to full optical density through a series of heat treatments. The final blank is cut ground and polished into the final optical component.