scholarly journals The achromatic design of an atmospheric dispersion corrector for extremely large telescopes

2011 ◽  
Vol 19 (18) ◽  
pp. 17099 ◽  
Author(s):  
Mehdi Bahrami ◽  
Alexander V. Goncharov
Keyword(s):  
Atmospheric Dispersion ◽  
Large Telescopes

scholarly journals Implementation and Use of Wide Fields in Future Very Large Telescopes

1984 ◽  
Vol 78 ◽  
pp. 549-562 ◽  
Author(s):  
J.R.P. Angel
Keyword(s):  
High Efficiency ◽  
Optical Design ◽  
Atmospheric Dispersion ◽  
General Purpose ◽  
Full Potential ◽  
Large Area ◽  
Full Field ◽  
Drift Scan ◽  
Large Telescopes ◽  
Ccd Arrays

AbstractThe full potential of the next generation of larger telescopes will be realized only if they have well instrumented large fields of view. Scientific problems for which very large ground-based optical telescopes will be of most value often will need surveys to very deep limits with imaging and slitless spectroscopy, followed by spectroscopy of faint objects taken many at once over the field. Improved instruments and detectors for this purpose are being developed. Remotely positioned fibers allow the coupling of light from many objects in the field to the spectrograph slit. CCD arrays, operated in the TDI or drift scan mode, will make large area detectors of high efficiency that may supercede photographic plates. An ideal telescope optical design should be based on a fast parabolic primary, have a field of at least 1° with achromatic images < 0.25 arcseconds and have provision for dispersive elements to be used for slitless spectroscopy and compensation of atmospheric dispersion over the full field. A good solution for a general purpose telescope that can satisfy these needs is given by a three element refractive corrector at a fast Cassegrain focus. A specialized telescope dedicated to sky surveys, with better image quality and higher throughput than presently available, might be built as a scaled up Schmidt with very large photographic plates. Better performance in most areas should be obtained with a large CCD mosaic detector operated in the drift scan mode at a telescope with a 2-mirror reflecting corrector.

scholarly journals Advanced Wide-Field Broad-Passband Refracting Field Correctors for Large Telescopes

1984 ◽  
Vol 79 ◽  
pp. 519-548 ◽  
Author(s):  
H.W. Epps ◽  
J.R.P. Angel ◽  
E. Anderson
Keyword(s):  
Image Quality ◽  
Atmospheric Dispersion ◽  
Wide Field ◽  
Atmospheric Refraction ◽  
Optical Elements ◽  
Large Telescopes ◽  
The University ◽  
Near Future ◽  
Optical Manufacturing ◽  
Made In

AbstractA preliminary 30-arcmin prime focus (f/2.0) refracting field corrector system for the University of California Ten-Meter Telescope (UC TMT) is presented which features 1/4-arcsec images containing more than 80% of the energy, over limited passbands within the wavelength range λ3300Å to λ1.0µ. Provision has been made in this system for an atmospheric dispersion corrector (ADC) but same has not yet been realized. Optical elements herein are small enough that this design could be scaled up to a Fifteen-Meter NNTT/SMT.A compact 40-arcmin internal Cassegrain (f/1.75 hyperbola to f/5.0) broad-passband (λ3300Å to λ1.0µ) corrector, suitable for imaging and multi-object spectroscopy at the UC TMT, is presented which features 1/4-arcsec images containing more than 90% of the energy when averaged over field angle and color.Three 60-arcmin external Cassegrain correctors for 300-inch f/1.8 and f/2.0 parabolic primary mirrors are presented which are suitable for a Fifteen-Meter NNTT/MMT. Image quality is comparable to the UC TMT Cassegrain corrector and it exceeds that of the UC TMT preliminary prime focus corrector system by a substantial margin. Each of these correctors contains an ADC which has been implemented in one example, eliminating 4.0 arcsec of differential atmospheric refraction with an rms residual of +/-0.10 arcsec over the broad passband (λ3300Å to λ1.0µ). A 60-arcmin external Cassegrain (f/1.8 extreme hyperbola to f/4.5) corrector with ADC yields yet a factor two in image quality but said hyperbolic primary mirror would be incompatible with angular field requirements in the thermal infrared.A (300-inch) 40-arcmin external Cassegrain (f/1.0 parabola to f/4.0) broad-passband (λ3300Å to λ1.0µ) corrector with ADC is presented. Image quality is comparable to the previous Cassegrain correctors. The practicality of this design, together with recent advances in optical manufacturing capability of large, fast, nonspherical optics, suggests that relatively inexpensive compact telescopes of very large collecting area may be possible in the near future.

scholarly journals Atmospheric dispersion compensation for extremely large telescopes

2007 ◽  
Vol 15 (4) ◽  
pp. 1534 ◽  
Author(s):  
Alexander V. Goncharov ◽  
Nicholas Devaney ◽  
Christopher Dainty
Keyword(s):  
Dispersion Compensation ◽  
Atmospheric Dispersion ◽  
Large Telescopes

scholarly journals A New Type of Atmospheric Dispersion Corrector Suitable for Wide-Field High-Resolution Imaging and Spectroscopy on Large Telescopes

2021 ◽  
Vol 11 (14) ◽  
pp. 6261
Author(s):  
Andrew Rakich
Keyword(s):  
High Resolution ◽  
Atmospheric Dispersion ◽  
Wide Field ◽  
High Resolution Imaging ◽  
Dispersion Correction ◽  
Atmospheric Effect ◽  
New Type ◽  
Resolution Imaging ◽  
Imaging And Spectroscopy ◽  
Large Telescopes

Atmospheric dispersion produces spectral elongation in images formed by land-based astronomical telescopes, and this elongation increases as the telescope points away from the zenith. Atmospheric Dispersion Correctors (ADCs) produce compensating dispersion that can be adjusted to best cancel out the atmospheric effect. These correctors are generally of two basic types: Rotating Atmospheric Dispersion Correctors (R-ADCs), and Linear Atmospheric Dispersion Correctors (L-ADCs). Lately, a third type, the “Compensating Lateral ADC” (CL-ADC) has been proposed. None of these design approaches allow for large corrector systems (with elements greater than 1 m in diameter), in which the secondary spectrum is corrected to small residuals, of the order of tens’ of milliarcseconds. This paper describes a new type of large corrector (>1 m diameter elements), which can achieve the correction of the secondary spectrum to the order of 10 milliarcseconds. This correction is achieved by combining the R-ADC and CL-ADC approaches to dispersion correction. Only glass types readily available in metre diameters are required.

Charles Gorrie Wynne. 18 May 1911 – 1 October 1999

2001 ◽  
Vol 47 ◽  
pp. 497-514
Author(s):  
Jonathan Maxwell ◽  
Prudence M.J.H. Wormell
Keyword(s):  
Bubble Chamber ◽  
Optical Design ◽  
Atmospheric Dispersion ◽  
Working Life ◽  
High Energy ◽  
Formative Period ◽  
Computer Assisted ◽  
Original Research ◽  
Lens Design ◽  
Large Telescopes

Charles Gorrie Wynne dedicated his professional life to optical design and became a principal figure in the international optical design community. When he died, he was optical consultant to the Institute of Astronomy in Cambridge and Emeritus Professor of Optical Design at Imperial College. Although nearly 90 years old he worked several days a week in the Institute of Astronomy until a few months before he died. He was elected to Fellowship of The Royal Society in 1970. Wynne's expertise was in the field of optical instrument design, particularly lens design. Among lens designers he is best known for his effective theories of lens design, his elegant and ambitious lens designs, and particularly his invention of a very successful method of computer-assisted lens design, based on the method of least squares. Among astronomers he is known for what is almost a monopoly of designs for field–widening optics for large telescopes, and also for a series of scientifically elegant spectrographs and atmospheric dispersion correctors. With microcircuit manufacturers he is famous for his work on the Wynne–Dyson catadioptric relay printer for microcircuit production. By high–energy physicists he is known as the designer of bubble–chamber optics; finally, he is known by his assistants and his students as their professional mentor. During the formative period of Charles Wynne's working life, optical design was performed almost exclusively behind the closed doors of optical factories. The optical designers in those factories traditionally led a monastic working life, closeted with a few close colleagues and assistants, grappling with the extensive numerical calculations that optical design involves. During the period of his career when he worked in this way, he managed to combine this type of working life with creative original research into new types of lens system and new methods of lens design.

The First Galaxies in the Universe

2013 ◽  
Author(s):  
Abraham Loeb ◽  
Steven R. Furlanetto
Keyword(s):  
Galaxy Evolution ◽  
Big Bang ◽  
First Stars ◽  
Distant Galaxies ◽  
Formation And Evolution ◽  
Early Galaxies ◽  
First Galaxies ◽  
Large Telescopes ◽  
New Generation ◽  
The Big Bang

This book provides a comprehensive, self-contained introduction to one of the most exciting frontiers in astrophysics today: the quest to understand how the oldest and most distant galaxies in our universe first formed. Until now, most research on this question has been theoretical, but the next few years will bring about a new generation of large telescopes that promise to supply a flood of data about the infant universe during its first billion years after the big bang. This book bridges the gap between theory and observation. It is an invaluable reference for students and researchers on early galaxies. The book starts from basic physical principles before moving on to more advanced material. Topics include the gravitational growth of structure, the intergalactic medium, the formation and evolution of the first stars and black holes, feedback and galaxy evolution, reionization, 21-cm cosmology, and more.

Sign in / Sign up

Export Citation Format

Share Document