File:Fresnel lighthouse lens diagram.png

From WikiMD's medical encyclopedia

Fresnel_lighthouse_lens_diagram.png ‎(492 × 578 pixels, file size: 88 KB, MIME type: image/png)

This file is from Wikimedia Commons and may be used by other projects. The description on its file description page there is shown below.

Summary

Description
English: Section diagram showing how a Fresnel lens (A) in a lighthouse works to collimate light from an oil lamp (L) into a parallel beam. The Fresnel lens, invented in 1822 by Augustin-Jean Fresnel, increased the light projecting power of lighthouses greatly without the weight of a conventional lens of its size. Also shown are mirror strips (m,n) mounted above and below the lens that most lighthouses had, to gather more of the lamp's light. Alterations: removed caption, erased blots in white areas, changed brightness levels to get rid of noise in white areas, sharpened light path lines.
Date
Source Downloaded from Adolphe Ganot (1872) Natural Philosophy for General Readers and Young Persons, D. Appleton & Co., New York, p.328, fig.257 (translated with permission from Ganot's Cours Élémentaire de Physique by Edmund Atkinson)
Author
Adolphe Ganot (1804–1887)  wikidata:Q365727 q:de:Adolphe Ganot
 
Description French physicist
Date of birth/death 2 May 1804 Edit this at Wikidata 10 December 1887 Edit this at Wikidata
Location of birth/death Rochefort Edit this at Wikidata Paris Edit this at Wikidata
Authority file
creator QS:P170,Q365727
Permission
(Reusing this file)		 Public domain - Ganot died in 1887; published in USA before 1923

Licensing

This is a faithful photographic reproduction of a two-dimensional, public domain work of art. The work of art itself is in the public domain for the following reason:
Public domain

The author died in 1887, so this work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 100 years or fewer.

This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1930.

This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.
The official position taken by the Wikimedia Foundation is that "faithful reproductions of two-dimensional public domain works of art are public domain".
This photographic reproduction is therefore also considered to be in the public domain in the United States. In other jurisdictions, re-use of this content may be restricted; see Reuse of PD-Art photographs for details.

Captions

Diagram of how a Fresnel lens works

Items portrayed in this file

depicts

media type

image/png

data size

90,202 byte

height

578 pixel

width

492 pixel

checksum

fc9774d4d632da8bbcdfb5244a37d059a41e3eb7

determination method or standard: SHA-1

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current10:03, 17 December 2007Thumbnail for version as of 10:03, 17 December 2007492 × 578 (88 KB)Chetvorno{{Information |Description=Diagram of how a Fresnel lens in a lighthouse works. |Source=Downloaded from [http://books.google.com/books?id=sKELAAAAYAAJ&pg=PA328 Adolphe Ganot (1872) ''Natural Philosophy for General Readers and Young Persons'', D. Appleton

The following page uses this file:

Retrieved from "https://wikimd.org/wiki/File:Fresnel_lighthouse_lens_diagram.png"