High resolution telescope

Patent · 01 January 1992

OSTI ID:868522

Massie, Norbert A ^[1]; Oster, Yale ^[2]

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1. San Ramon, CA
2. Danville, CA

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 employs 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 an 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 activites. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• DOE Contract Number: W-7405-ENG-48
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 5159489
• OSTI ID: 868522
• Country of Publication: United States
• Language: English

Related Subjects

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02
12
achieve
activites
aperture
array
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ccd
center-mount
circle-of-nine
compared
configuration
constant
construction
contribute
conventional
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diffraction-limited
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electro-optical
elemental
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eliminating
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mitigated
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non-redundant
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orbit
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pathlength
phased
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power
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silicon
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steerable
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third
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