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to be placed at this location, so that the light from outside the field of view does not reach the secondary mirror. This is a major advantage for solar telescopes, where a field stop (Gregorian stop) can reduce the amount of heat reaching the secondary mirror and subsequent optical components. The
94:, 1636). Gregory's early attempts to build the telescope failed, since he had no practical skill himself and could find no optician capable of actually constructing one. It was not until ten years after Gregory's publication, aided by the interest of experimental scientist
56:, built by Sir Isaac Newton in 1668. However, Gregory's design was only a theoretical description, and he never actually constructed the telescope. It was not successfully built until five years after
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The
Gregorian design solved the problem of viewing the image in a reflector by allowing the observer to stand behind the primary mirror. This design of telescope renders an
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In the
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The
Gregorian telescope is named after the James Gregory design, which appeared in his 1663 publication
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the
Gregorian can be less difficult to fabricate than a Cassegrain because the concave secondary is
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Mirror Lab has been making mirrors for large
Gregorian telescopes at least since 1985.
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built
Gregorian telescopes with parabolic mirrors made from the highly reflective
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Gregorian reflecting telescope, Who was James
Gregory, National Museums Scotland.
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like the primary, which is not the case with the
Cassegrain's convex secondary.
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because this design creates an erect image without the need for prisms. The
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Stargazer, the Life and Times of the
Telescope, by Fred Watson,
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361:"Isaac Newton: adventurer in thought", by Alfred Rupert Hall,
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are all radio telescopes employing off-axis
Gregorian optics.
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The Encyclopedia of Astrobiology, Astronomy, and Spaceflight
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Diagram of the lightpath through a Gregorian telescope
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with its tube much shorter than the system's actual
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44:in the 17th century, and first built in 1673 by
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329:is the inventor of the Gregorian telescope.
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186:satellite is one example of this design.
162:The design was largely superseded by the
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114:The Gregorian telescope consists of two
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37:designed by Scottish mathematician and
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238:1873 diagram of a Gregorian telescope
48:. James Gregory was a contemporary of
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16:Type of astronomy magnifier
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339:Large Binocular Telescope
278:Large Binocular Telescope
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452:14 February 2012 at the
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285:Giant Magellan Telescope
191:amateur telescope makers
333:James Gregory Telescope
307:List of telescope types
91:L'harmonie universalle
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416:"Gregorian Telescope"
280:use Gregorian optics.
263:Allen Telescope Array
76:Bonaventura Cavalieri
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255:Green Bank Telescope
164:Cassegrain telescope
35:reflecting telescope
549:Scottish inventions
274:Magellan telescopes
259:Arecibo Observatory
172:Steward Observatory
81:Lo Specchio Ustorio
54:Newtonian telescope
31:Gregorian telescope
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321:Teide Observatory
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149:erect image
100:James Short
538:Categories
350:References
276:, and the
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123:paraboloid
39:astronomer
480:Astronomy
422:5 January
226:Side view
134:ellipsoid
450:Archived
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301:See also
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363:page 67
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201:Gallery
138:primary
119:mirrors
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64:History
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184:Hinode
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110:Design
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