Edge Bonding of Infrared Windows
Navy SBIR FY2008.2

Sol No.: Navy SBIR FY2008.2
Topic No.: N08-134
Topic Title: Edge Bonding of Infrared Windows
Proposal No.: N082-134-0252
Firm: Onyx Optics, Inc.
6551 Sierra Lane
Dublin, California 94568-2798
Contact: Helmuth Meissner
Phone: (925) 833-1969
Web Site: www.onyxoptics.com
Abstract: Onyx Optics, Inc. proposes to apply its patented AFBr (Adhesive-Free Bond) composites process that has been developed for solid state laser components to the edge bonding fabrication of IR windows. The key process step is to obtain optical contact between the components to be bonded, followed by heat treatment. There are a number of techniques of establishing this optical contact but they all result in an interface that is bonded mainly through Van der Waals forces after at least moderate heat treatment and out-diffusion of volatile species. Van der Waals forces consist of three types: fixed dipole/fixed dipole interactions, fixed dipole/induced dipole interaction, and induced dipole/ induced dipole interactions, respectively. They become prominent when the separation distance between two adjacent solid bodies becomes much smaller than any wavelength of the random dipole field. Lifshitz quantum field theory will be applied to the specific case of composite infrared windows and linked to experimental results. AFBr composites will be characterized and compared with non-composite controls in terms of: Mechanical properties: tensile fracture strength, fracture toughness, elastic modulus, stress birefringence. Optical properties: Transmitted wavefront as function of angle of incidence, refractive index, transmission between visible to far IR.
Benefits: The proposed process will result in edge-bonded IR windows with optical quality interfaces. The process is applicable to sapphire, optical ceramic spinel and optical ceramic aluminum oxynitride.