Printer Friendly
Dictionary, Encyclopedia and Thesaurus - The Free Dictionary
3,921,757,326 visitors served.
forum Join the Word of the Day Mailing List For webmasters
?
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

Piazzi-Smyth Lens

    0.03 sec.
Piazzi-Smyth Lens 

a lens mounted directly in front of the focus of an astrograph to correct its curvilinear field. The surface of a Piazzi-Smyth lens facing the photographic plate is made flat; the surface facing the objective has a radius of curvature r = R(n – 1) /n, where R is the radius of curvature of the field and n is the refractive index of the glass from which the lens is made. The aberrations introduced by a Piazzi-Smyth lens are small. By also assigning curvature to the second surface of the lens, it is possible to correct the distortion of the astrograph objective. The Piazzi-Smyth lens was invented by the British scientist C. Piazzi-Smyth in 1874.



Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link
Feedback
Mentioned in?   Encyclopedia browser?   Full browser?
No references found
 
 
 
Encyclopedia
?

Terms of Use | Privacy policy | Feedback | Advertise with Us | Copyright © 2012 Farlex, Inc.
Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.