Subaru Coronagraphic Extreme-AO (SCExAO) wavefront control: Current status and ongoing developments

Ananya Sahoo, Olivier Guyon, Christophe S. Clergeon, Nour Skaf, Yosuke Minowa, Julien Lozi, Nemanja Jovanovic, Frantz Martinache

Research output: Chapter in Book/Report/Conference proceedingConference contribution

7 Scopus citations


Exoplanet imaging requires excellent wavefront correction and calibration. At the Subaru telescope this is achieved us- ing the 188-element facility adaptive optics system(AO188) feeding the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument; a multipurpose instrument built to deliver high contrast images of planets and disks around nearby stars. AO188 offers coarse correction while SCExAO performs fine correction and calibration of 1000 modes. The full system achieves 90%Strehl Ratio in H-band and diffraction limited images. A new Real Time Computer allowing higher performance between SCExAO and AO188 is currently implemented. Future upgrades will include a new Pyramid Wavefront Sensor and (64x64) DM to achieve extreme AO correction inside AO188. We are progressing in the development of predictive control and sensor fusion algorithms across the system to improve performance and calibration. With the new upgrades, SCExAO will be able to image giant planets in reflected light with Subaru and validate technologies necessary to image habitable Earth-like planets with the Thirty Meter Telescope (TMT).

Original languageEnglish (US)
Title of host publicationAdaptive Optics Systems VI
EditorsDirk Schmidt, Laura Schreiber, Laird M. Close
ISBN (Print)9781510619593
StatePublished - 2018
EventAdaptive Optics Systems VI 2018 - Austin, United States
Duration: Jun 10 2018Jun 15 2018

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


OtherAdaptive Optics Systems VI 2018
Country/TerritoryUnited States


  • adaptive optics
  • astronomical instrumentations
  • exoplanet
  • wavefront control
  • wavefront sensors

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Subaru Coronagraphic Extreme-AO (SCExAO) wavefront control: Current status and ongoing developments'. Together they form a unique fingerprint.

Cite this