We present the first on-sky segmented primary mirror closed-loop piston control using a
Zernike wavefront sensor (ZWFS) installed on the Keck II telescope. Segment cophasing …

Conventional wavefront sensors suffer from the fundamental limitation of the space‐
bandwidth product and have a trade‐off between their spatial sampling interval and dynamic …

Context. Telescopes like the Extremely Large Telescope (ELT) and the Giant Magellan
Telescope (GMT) will be used together with extreme adaptive optics (AO) instruments to …

High-speed adaptive correction of optics, based on real-time metrology feedback, has
benefitted numerous scientific communities for several decades. However, it remains a …

The next generation of large ground-and space-based optical telescopes will have
segmented primary mirrors. Co-phasing the segments requires a sensitive wavefront sensor …

Future space telescopes with coronagraph instruments will use a wavefront sensor (WFS) to
measure and correct for phase errors and stabilize the stellar intensity in high-contrast …

Aims. The Zernike wavefront sensor (ZWFS) is a concept belonging to the wide class of
Fourier-filtering wavefront sensors (FFWFSs). The ZWFS is known for its extremely high …

Context. The combination of large segmented space telescopes, coronagraphy, and
wavefront control methods is a promising solution for producing a dark hole (DH) region in …

The Extremely Large Telescopes will require hundreds of actuators across the pupil for high
Strehl in the visible. We envision a triple-stage AO (TSAO) system for GMT/GMagAO-X to …

Following the success of the Decadal Survey Testbed (DST), the HCIT team at JPL has
developed a companion testbed, the Decadal Survey Testbed 2 (DST2), that further …