Holographic Optical Element for Through the Air Link Optical Component (TALOC)

Size, Weight, Power and Cost (SWAP-C) are significant influencers in the design and operation of mobile Free Space Optical (FSO) communications hardware. As FSO technology evolves to applications for smaller vehicles such as Unmanned Air Vehicles (UAV), the need for reduced size and weight optics becomes critical. Large, heavy glass optical elements are required in today’s FSO units to acquire the weak signals from distant transmitters. Utilization of conventional optics is limited to glass type, optical density, and aperture size when designing these elements. Additionally, either gimbals or motorized prism-based scanning units are currently the standard for controlling the direction and field of regard of these units. These components severely impact the attainable size and weight of FSO systems. Elimination of scanners and gimbals enables the design of FSO technologies with significantly reduced footprints and SWAP.Diffractive Optical Elements (DOE) and especially one specific subset, Holographic Optical Elements (HOE), rise as potential solutions with many additional benefits beyond SWAP-C. The weight savings from a HOE or DOE collection lens on the receiver side of an FSO communications unit is tremendous.