Adaptive optics for array telescopes using neural-network techniques

J. R.P. Angel, P. Wizinowich, M. Lloyd-Hart, D. Sandler

Research output: Contribution to journalArticle

68 Scopus citations

Abstract

IMAGES formed by ground-based telescopes are marred by atmospheric 'seeing9. The plane wavefront from an unresolved star is distorted by continually changing turbulent fluctuations in the air's refractive index. Diffraction-limited performance can in principle be recovered through the methods of adaptive optics, in which the instantaneous wavefront shape is sensed and corrected in real-time by deformable optics that cancel the distortion1,2. The highest resolution will be achieved when this technique is applied to multiple-telescope arrays. For such arrays, the biggest errors caused by seeing at infrared wavelengths are the variations in pathlength and wavefront tilt between array elements. We show here that these errors can be derived by an artificial neural network, given only a pair of simultaneous in-focus and out-of-focus images of a reference star formed at the combined focus of all the array elements. We have optimized a neural network appropriate for 2.2-μm wavelength imaging at the Multiple Mirror Telescope in Arizona. Corrections made by moving the beam-combining mirrors will largely recover the diffraction-limited profile, with a resolution of 0.06 arcsec.

Original languageEnglish (US)
Pages (from-to)221-224
Number of pages4
JournalNature
Volume348
Issue number6298
DOIs
StatePublished - Jan 1 1990

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Adaptive optics for array telescopes using neural-network techniques'. Together they form a unique fingerprint.

  • Cite this