Diffractive Element Millimeter Wave/Infrared Beam Combiner

In order to overcome fabrication problems associated with large size millimeter wave/infrared (MMW/IR) beamcombiner, WaveBand Corporation proposes to design and develop a diffractive optical element (DOE) on a plastic substrate. This DOE fabricated out of material with very low MMW absorption will cause minimal degradation of the passing MMW beam. At the same time, it will work as a diffractive lens by redirecting the IR beam from the image generator to the unit under test. The proposed DOE beamcombiner made out of a parallel plate will be installed perpendicular to the incident MMW beam, thus introducing only minimal phase error. It will accommodate the IR projector optics and, in addition, can replace some of the projector lenses. The DOE combiner utilizes inexpensive material and fabrication technology suitable for reflection and mass production of large-size elements. It will eventually be installed and tested at the U.S. Army Missile Command Simulation System in a dual-mode common-aperture simulator for missile super testing.