High Transmission Diamond IR Windows without AR Coatings

Existing electro-optical systems of missile interceptor kill vehicles and/or seeker satellites typically use long wave infrared sensor systems and illumination devices that have optical components which would benefit from improved transmission efficiency at critical IR wavelengths. These components must also operate in potentially harsh environments both physically and with respect to radiation from nuclear events. As a result, any improvement in structural reliability or radiation resistance would also be beneficial. Diamond optics with diffractive AR structures offer a possible answer to these problems if they can be made into the necessary shapes in a cost effective manner. The proposed technical effort therefore is to develop processes, equipment and procedures for manufacturing large diameter diamond IR windows and lenses with transmission levels above 97% without the need of AR coatings. The optical design includes structured surfaces that create diffractive or negative index surfaces that will significantly minimize reflections at IR wavelengths. The diamond used for these windows will be grown with low cost processes and standard fabrication equipment.