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Freeform optics

Freeform optics are optical elements (reflective, transmissive, or diffractive) with no particular axis of rotation or symmetry. They are increasingly used in pioneering optical designs offering abundant new opportunities for optical designers. Freeform surfaces help to improve compactness, image sharpness and contrast in a larger field of view. Freeform optics are therefore promising components for airborne or space-based imagers for their ability to reduce the overall dimension, and therefore mass, of the satellite’s payload, which is a critical parameter in space imaging systems.

ray tracing diagram of Compact Three Mirror Anastigmat telescope for CubeSat free-space communications

Compact Three Mirror Anastigmat telescope for CubeSat (EFFL = 500mm, F/# = 4.5) as part of the Enabling Technology Program from UKSA (ETP-040)

The Centre for Advanced Instrumentation (CfAI) at Durham University has participated in the development of the Lunar Thermal Mapper (LTM) infrared multispectral image in collaboration with Oxford University and RAL Space on the UK side, and NASA, JPL Caltech, Lockheed Martin on the US side. The LMT is an instrument of the Lunar Trailblazer (NASA SIMPLEx small planetary science mission) which will detect and map water on the lunar surface. CfAI will provide the 5 all aluminium freeform optics of the LMT. CfAI acknowledges the support received from the UK Space Agency (ST/W000849/1)

All-aluminium freeform optical system for the Lunar Thermal Mapper

All-aluminium freeform optical system for the Lunar Thermal Mapper (courtesy Oxford University)