Jonathan Fan
Stanford University
Infrared spectrometers are essential instruments in a broad range of scientific space missions, including those deployed for lunar, Mars and other astronomical and planetary studies. The optical systems of these instruments tend to be very complex. They contain multiple curved mirrors, reflections from gratings, refractive optics and beam splitters, which add significant mass and volume to the mission payload, as well as complexity due to the number of optical surfaces that must be aligned and maintained during the mission. The project objectives include developing concepts based on freeform metasurfaces, which can both focus and disperse light and more generally add multiple functions not easily achieved in classical optical systems. They have the potential to reduce the complexity, mass and volume of optical systems used in wide bandwidth hyperspectral image sensors. This development will be achieved by: (1) application of advanced topological optimization; (2) development of surrogate electromagnetic solvers; (3) fabrication of centimeter-scale reflective mestasurfaces operating across one octave (8 to 16 mm); and (4) characterization of the fabricated devices.