Quantum-optimal instruments for high-contrast imaging with multi-plane light converters

Abstract

Spatial Mode Demultiplexers (SPADE) are devices that split an incoming wavefront into a particular set of electric field modes. SPADEs have been shown to be quantum-optimal for many measurement problems including coronagraphy, wavefront sensing and interferometric (nulling) beam combiners. We will show how quantum optimal SPADEs can be implemented using Multi Plane Light Converters (MPLC). MPLCs are devices that use several phase plates in sequence to achieve arbitrary unitary transformations. The phase plates themselves are implemented using liquid-crystal technology that allows us to create high-quality broadband phase plates. The accurate control of the local phase through the direct write method results in MPLCs with minimal background scatter. We will show the designs and simulated performance for each of the proposed use cases for the ELTs, HWO and LIFE and show how they improve over current concepts.

Submitted to SPIE Astronomical Telescopes and Instruments. Proc. SPIE 14154, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation VII, 1415419 (21 Aug 2026)