The phase-apodized-pupil Lyot coronagraph (PAPLC) is a pairing of the apodized-pupil Lyot coronagraph (APLC) and the apodizing phase plate (APP) coronagraph that yields (in numerical simulations) inner working angles as close as 1.4 lambda/D at contrasts of 10^-10 and post-coronagraphic throughput of <75% for telescope pupils with central obscurations of up to 30%. PAPLC designs with a phase-only apodizer are entirely achromatic. Here we show that a single deformable mirror (DM) can serve as the phase apodizer in monochromatic light. We present the first laboratory demonstration of the PAPLC on a segmented telescope pupil, created by an IrisAO segmented DM, on the High-contrast imager for Complex Aperture Telescopes (HiCAT) testbed. We offset the focal-plane mask in HiCAT, made for an APLC coronagraph, to act as the knife edge for the PAPLC. By defocusing the target acquisition camera installed on HiCAT, we can perform single-image phase retrieval on this camera. As this camera uses only light that is transmitted and filtered by the focal-plane mask, it enables simultaneous wavefront sensing and coronagraphic imaging. We study the capability of this wavefront sensor to recover drifts in piston, tip and tilt on the individual segments on the IrisAO DM installed on HiCAT.
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