Stabilization of light sources with digital micromirror devices for calibration of high-precision photometric instruments
Year: 2024
Type: article
Abstract: To answer the new challenges imposed by the most recent exoplanet space missions, testing and calibrating high-precision photometric instruments requires a highly stable illumination system, which is a great challenge when the mission’s required photometric stability is a few ppm for long observation periods. Traditional calibration sources do not fulfil the stability requirements of the most demanding missions. It is necessary to use additional methods to compensate for flux fluctuations. This study introduces a new method, using a Digital Micromirror Device (DMD) as an intensity light modulator. DMD is a micro-electromechanical device developed by Texas Instruments, that consists in a two-dimensional array of micromirrors. Each micromirror can be individually tilted between two positions. Controlling the state of each micromirror it is possible to control the flux of light that goes in a particular direction. This technology enables fast modulation speeds, with high precision and broadband capabilities. This study presents an exploratory work on the technical feasibility of using DMDs to compensate light source fluctuations, accurately modulating the beam of light coming from a Halogen (QTH) or a Laser Driven Light Source (LDLS). We developed a proof-of-concept method able to reduce light source fluctuations from ± 1.3% to ± 0.1% (p2p), based in a simple open loop methodology.
Language: English
Subfield: Instrumentation
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4404048455