Binary Optics Microlenses for HgCdTe Focal Plane Arrays

Binary optics can be used for fabrication of microlenses for IR focal plane arrays (FPAs). There is a need to improve the light collection efficiency and reduction in size for the detectors to improve on the signal to noise ratio and relaxation of the cooling requirements. Binary optics lenses can be used to reduce the area of the detectors by a factor of 10 to 20. We propose to design and fabricate multiphase Fresnel lenses with high collection efficiency and F/# to 0.5 for 8-12 micrometer wavelength range. We will fabricate multiphase lens of CdTe substrate in the first phase and evaluate them. In the second phase we will fabricate microlens array on CdTe substrate for HgCdTe FPAs working with one or more FPA vendors. The technology for microlens fabrication could be used for other types of FPAs in the visible and near IR wavelenths as well as for fabrication of large lenses on wafers. The large area binary lenses can be used to replace the refractive lenses with tremendous reduction in weight and size for the optical systems in the visible and infrared. Anticipated Benefits: Microlenses on focal plane arrays will have tremendous impact on DoD systems using them and a number of commercial products can be developed using binary optic lenses which can be available in smaller size, lower weight, higher performance and significant cost advantage.