Revisiting optical transfer function-based focal plane wavefront sensors for correcting NCPAs

Abstract

We examine several focal plane wavefront sensing (FPWFS) approaches from a theoretical perspective, specifically comparing their fundamental origins and similarities. We consider various techniques, including the differential optical transfer function wavefront sensor, the self-coherent camera wavefront sensor, the fast-modulated selfcoherent camera wavefront sensor, and other variants, as well as pair-wise probing. They are evaluated within a unified framework based on precise optical transfer function analysis and their implementation on the highcontrast imaging SPEED test bed. These concepts are highly similar in essence, even serving as mere extensions of one another. Indeed, we emphasise that these FPWFS can be seen as different expressions or embodiment of the same underlying principles