Interferometric Apodization using Deformable Mirror in a Michelson Interferometer to Improve Exoplanet Detection – I. Theoretical Foundations

Abstract To capture images of Earth-like planets orbiting distant stars, advanced instruments with exceptional contrast ratios are imperative. While coronagraphs play a crucial role, they often lack the capability to achieve the requisite contrast levels independently. Hence, supplementary apodization techniques are indispensable for augmenting their rejection capabilities. In this context, we introduce an innovative apodization method that harnesses interferometry, seamlessly integrating a deformable mirror into the Michelson interferometer setup. This sophisticated approach entails splitting the incident Point Spread Function (PSF) into two components, introducing an additional inhomgenious phase φ ( x , y ) to one of them via a deformable mirror, and subsequently recombining them to yield an apodized PSF. We illustrate, in particular, the influence of several parameters of the deformable mirror on the optimization of the additional phase profile.