Chromatic aberration of eyepieces in early telescopes.
The twofold objective of this study is (1) to identify and give a brief review of the historical development of the various designs of early (pre-1850) telescope eyepieces, and (2) to determine by measurements and calculations the axial and lateral chromatic aberrations of a number of extant eyepiec...
| Publicado en: | Annals of Science Vol. 64; no. 1; pp. 1 - 19 |
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| Formato: | Artículo |
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Taylor & Francis Ltd
Jan2007
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=23463002&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 23463002 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00033790 7J1 jtl: Annals of Science issn: 00033790 maglogo: Y pubinfo: dt: Jan2007 vid: 64 iid: 1 pid: 377 pub: Taylor & Francis Ltd artinfo: ui: 23463002 10.1080/00033790601035360 ppf: 1 ppct: 18 formats: fmt: – @attributes: type: T – @attributes: type: P size: 305KB tig: atl: Chromatic aberration of eyepieces in early telescopes. aug: au: Eugene Rudd, M. affil: Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0111, USA su: Achromatism Telescopes Refractive index Optical instruments Galilei, Galileo, 1564-1642 Van Helden, Albert Kepler, Johannes, 1571-1630 sug: subj: Achromatism Telescopes Refractive index Optical instruments Galilei, Galileo, 1564-1642 Van Helden, Albert Kepler, Johannes, 1571-1630 ab: The twofold objective of this study is (1) to identify and give a brief review of the historical development of the various designs of early (pre-1850) telescope eyepieces, and (2) to determine by measurements and calculations the axial and lateral chromatic aberrations of a number of extant eyepieces from that period in order to provide basic data on which to judge the relative quality of different eyepiece forms. Eight distinct types of eyepieces containing one to five lens elements are discussed and illustrated. The second objective was addressed by measuring the focal lengths of the individual lens elements and the lens spacings in each eyepiece. The data were processed by a ray-tracing program that yields the chromatic aberration (CA) and focal length of each of the eyepieces. Twenty-one telescopes from that period were studied in this way. Similar calculations were also made using data available in the literature on several additional historic telescopes. The conclusions drawn from the data are: (1) Telescopes with Galilean eyepieces have a smaller CA than those with Keplerian or Huygens eyepieces. (2) The two-lens Keplerian terrestrial eyepieces are demonstrated to have larger axial and lateral CA than any of the other eyepiece types. (3) Calculations from examples of telescopes by Divini and Campani for which data were available indicate that while the axial CAs of the two were the same, Campani's instrument had a much smaller lateral CA. (4) Five element eyepieces were found to be better corrected for CA than the early four-lens systems that replaced them. (5) This study tends to confirm the speculation that the reason makers of early achromatic telescopes overcorrected the objective lenses was to compensate for the CA of the eyepieces. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y custom: Copyright of Annals of Science is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. item: Annals of Science holder: Taylor & Francis Ltd dt: @attributes: year: 2007 holdings: @attributes: islocal: N |
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