High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center
Abstract
A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employes speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by a electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activities. The cost of the telescope scales with the first power of the aperture rather than its third powermore »
- Inventors:
-
- San Ramon, CA
- Danville, CA
- Issue Date:
- Research Org.:
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
- OSTI Identifier:
- 868258
- Patent Number(s):
- 5108168
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
G - PHYSICS G02 - OPTICS G02B - OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS
- DOE Contract Number:
- W-7405-ENG-48
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- resolution; telescope; including; array; elemental; telescopes; aligned; common; axis; supported; space; frame; pivot; geometric; center; effective-aperture; low-cost; optical; diffraction-limited; enables; ground-based; observation; near-earth; non-redundant; thinned-aperture; center-mount; single-structure; employes; speckle; interferometric; imaging; achieve; signal-to-noise; ratio; mitigated; moving; wavelength; operation; near-ir; image; sensed; silicon; ccd; steerable; constant; pupil; radar-like; mount; low-earth; orbit; tracked; increases; stiffness; preferred; embodiment; subaperture; circle-of-nine; configuration; effective; aperture; 12; provides; 02; pathlength; matching; maintained; electro-optical; employing; laser; metrology; relaxes; tolerance; magnitude; compared; phased; arrays; features; contribute; substantial; reduction; costs; eliminating; conventional; protective; dome; reducing; on-site; construction; activities; cost; scales; power; third; diffraction-limited resolution; space frame; signal-to-noise ratio; preferred embodiment; substantial reduction; noise ratio; common axis; speckle imaging; telescope array; laser metrology; resolution telescope; resolution enables; orbit space; optical telescope; phased array; near-earth space; geometric center; elemental telescopes; telescope including; thinned-aperture array; ground-based observation; enables ground-based; low-cost optical; /359/
Citation Formats
Norbert, Massie A, and Yale, Oster. High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center. United States: N. p., 1992.
Web.
Norbert, Massie A, & Yale, Oster. High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center. United States.
Norbert, Massie A, and Yale, Oster. Wed .
"High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center". United States. https://www.osti.gov/servlets/purl/868258.
@article{osti_868258,
title = {High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center},
author = {Norbert, Massie A and Yale, Oster},
abstractNote = {A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employes speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by a electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 1992},
month = {Wed Jan 01 00:00:00 EST 1992}
}
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