File:Contre miroir.png
Contre_miroir.png (391 × 209 pixels, file size: 4 KB, MIME type: image/png)
Captions
Summary
[edit]DescriptionContre miroir.png |
Français : Projecteur à miroir parabolique et contre-miroir sphérique
Sans contre-miroir (figure de gauche), une partie des rayons de l'ampoule sortent par l'ouverture du miroir sans être dévié, ils ne contribuent pas au faisceau parallèle. projetté sur un mur, on obtient un disque lumineux entouré d'un halo dont l'intensité s'estompe avec l'éloignement. Avec un contre-miroir (figure de droite, le contre-miroir sphérique récupère les rayons qui s'échappaient par devant et les rabat sur le miroir parabolique. On n'a plus de halo, tous les rayons contribuent au faisceau parallèle, mais on a une tache sombre au milieu. Les miroirs sont en réalité beaucoup plus tronqués, ils n'enveloppent pas l'ampoule. Auteur : Christophe Dang Ngoc Chan, réalisé avec un programme de dessin vectoriel Licence GFDL Christophe Dang Ngoc Chan |
Date | 22 January 2004 (original upload date) |
Source | Transferred from fr.wikipedia to Commons by Bloody-libu using CommonsHelper. |
Author | The original uploader was Cdang at French Wikipedia. |
Licensing
[edit]Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue |
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. | ||
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This licensing tag was added to this file as part of the GFDL licensing update.http://creativecommons.org/licenses/by-sa/3.0/CC BY-SA 3.0Creative Commons Attribution-Share Alike 3.0truetrue |
Original upload log
[edit]- 2004-01-22 14:10 Cdang 391×209× (4595 bytes) Contre-miroir sphérique
File history
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 15:39, 9 August 2012 | 391 × 209 (4 KB) | File Upload Bot (Magnus Manske) (talk | contribs) | Transfered from fr.wikipedia by User:Bloody-libu using CommonsHelper |
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File change date and time | 14:10, 22 January 2004 |
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