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arXiv · 2601.23176

HEP digital micromirror devices for precision solar spectroscopy

Christian Robles·Suvrath Mahadevan
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Abstract

We present the motivation and early tests for a novel solar instrument that will harness the new High Efficiency Pixel (HEP) Texas Instruments DLP801RE Digital Micromirror Device (DMD) as a reconfigurable spatial light modulator. This design enables real-time, dynamic configuration of the field of view for targeted spectroscopy of magnetically active regions and full-disk observations. Optical efficiency was validated through simulations and laser testing. Destructive window removal allowed for detailed structural analysis, confirming the elimination of central vias present in previous models. We measured a contrast ratio of 250:1, currently limited by the evaluation board's duty cycle rather than the DMD itself. Furthermore, we successfully simulated artificial planetary transits, recovering depths ranging from gas giants to a 40 ppm rocky planet transit. These results demonstrate the HEP DMD's potential for high-precision solar and exoplanetary science applications.

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Christian Robles, Suvrath Mahadevan. 2026-01-30. HEP digital micromirror devices for precision solar spectroscopy. https://doi.org/10.1117/12.3080954

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