Precise simulation enables rapid design iterations for a radial velocity instrument, building confidence in spectrograph design

The Department of Physics at the University of Notre Dame (UND) in Indiana supports wide-ranging astronomy research from ground-based optical and infrared astronomy, as well as in space science and theoretical astrophysics and cosmology. Many of its ground-based observational achievements come from its famous partnership with one of the world's most powerful and versatile telescope projects, the Large Binocular Telescope (LBT) at the Mount Graham International Observatory in Arizona. Scientists from United States, Italy, and Germany use the LBT to address astronomical challenges ranging from the study of objects in our solar system to studies of the early universe.

UND originally used Zemax to design and optimize the instrument fiber injection system for LBT, which was successfully commissioned at the telescope in 2019. More recently, the university has embarked on developing the Doppler spectrometer element of the instrument that includes one of the first diffraction-limited spectrographs to be used for extremely precise RV studies of exoplanets. To achieve this sub-meter-per-second precision, it was necessary to build capabilities into a spectrograph for its iLocater project, the first optimized single-mode fiber fed radial velocity-based instrument for the exoplanetary discovery and study.

Zemax OpticStudio played a key role in enabling the iLocater team to accurately simulate and track end-to-end diffraction-limited performance for a Gaussian system, an essential need for developing iLocater as well as other diffraction-limited spectrographs in the future. The team also used OpticStudio to simulate physical-optics propagation (POP) effects, the ideal method for achieving accuracy in optical system development for diffraction-limited spectrographs.

"The level of accuracy OpticStudio provides for POP simulation has made us significantly more productive as we continue optimizing our system," said Dr. Jonathan Crass, Assistant Research Professor in the Notre Dame Department of Physics. "With Zemax, we had a single, comprehensive software solution for tracking wavefront performance that also allowed simple integration into our CAD software for optomechanical design."

Read the full story to learn more background on each of these terms and concepts, and to hear the full story of how Crass and his team successfully conducted their simulations using OpticStudio. And to learn more about OpticStudio, the industry standard for optical design software, try it for free!