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----
-title: "The optics for everyday life"
-media_order: 'chrono_text_opt_geo_fr_v2.jpeg,sciences_optique_rays_fr.jpeg,chrono_opt_geo_fr_v2.jpeg,Opt_geom_1.jpg,OG_intro.mp3,OG_intro.ogg'
-published: true
-visible: false
-lessons:
-    - slug: geometrical-optics-domain-of-validity
-      order: 2
----
-
-### The optics for everyday life
-
-![](Opt_geom_1.jpg)
-
-[AUDIO : _Geometrical optics: the optics of everyday life_](OG_intro.mp3)
-
-#### Geometrical optics lets us understand :
-
-* The **Vision**
-* **Optical instruments** : * magnifiers, telescopes, microscopes, cameras with telephoto and macro lenses*
-* **Eyeglasses and contact lenses** to correct vision defects.
-* Optical phenomena such as **fog, rainbows, mirages**.
-* The operation of a **fiber optic**.
-
-<!--text of the audio:
-If geometric optics is the oldest science of optics, it is really the one that applies to the closest to our everyday life.
-It helps to understand how the eye perceives its environment. It also helps to understand how conventional optical devices work, such as the camera with its zoom or various lenses, the microscope, the telescope and the astronomical or terrestrial glasses.
-It also makes it possible to characterize the defects of the eye, to understand how eyeglasses and contact lenses correct these defects, and to calculate their profiles according to the defects to be corrected.
-It allows to understand the optical phenomena like the rainbow (as well its colors as its shape and its position with respect to the sun) and like the mirages observed sometimes in the desert.
-Finally, it allows us to understand how light can propagate in an optical fiber, which is at the base of all modern terrestrial communication networks.-->
-
-#### Geometrical optics : the oldest science of optics
-
-*Chronological vision*, brief and imperfect, *dated from the present time*
-
-![](historic-rays-optics_en_L1200.jpg)
-
-<!--======================================
-Don't worry, the table below is well formatted on browsers.
-To translate into English, or to modify or complete then translate into es and fr
-in the files cheatsheet.es.md and cheatsheet.es.md and cheatsheet.fr.md and 
-========================================-->
-
- | |
- --- | ---
-*dates* | *in Gregorian calendar (usual calendarl)*
-<span style="color: #0066cc">&#8226; &#8776; -2500 </span> |  <span style="color: #0066cc">premières fabrications en verre translucide, en Mésopotamie et Égypte.</span>
-<span style="color: #0066cc">&#8226; -2000 à -1000</span> |  <span style="color: #0066cc">divers éléments en quartz volontairement polis</span>
-<span style="color: #0066cc">&#8226; -850 &pm; 150 </span> | <span style="color: #0066cc">la *lentille de Nimrud*, peut-être plus ancien instrument d'optique jamais découvert.</span>
-<span style="color: #993333">&#8226; [-478;-391]</span> | <span style="color: #993333">Mozi (philos. chinois) : étude chambre noire : propagation rectiligne lumière et image inversée</span>
-<span style="color: #993333">&#8226; [-383;-321]</span> | <span style="color: #993333">Aristote (philos. grec) / réflexions et interprétations de phénomènes lumineux.</span>
-<span style="color: #993333">&#8226; &#8776;-300 </span> | <span style="color: #993333">*Euclide* (philos. grec) ,*traité d'optique* : propagation rectiligne, perspective, réflexion &amp; réfraction.</span>
-<span style="color: #993333">&#8226; &#8776;+130</span> | <span style="color: #993333">*Ptolémée* (philos. grec) : *traité d'optique* : vision, couleurs, réflexion &pm; réfraction.</span>
-<span style="color: #0066cc">&#8226; > 200</span> | <span style="color: #0066cc">1ère apogée *techniques des miroirs et du verre transparent* (entre autre pour vitrage).</span>
-<span style="color: #993333">&#8226; [965;1039]</span> | <span style="color: #993333">*Ibn al-Aytham* (ou Alhacen) : *traité d'optique* : ouvrage fondateur, transforme les connaissances : lumière &pm; vision, réflexion &pm; réfraction, grandissement des lentilles.</span>
-<span style="color: #993333">&#8226; [1214;1294]</span> | <span style="color: #993333">*Bacon : traité "Opus major"*, expériences lentilles convergentes, propriétés de focalisation.</span>
-<span style="color: #0066cc">&#8226; 1285</span> | <span style="color: #0066cc">*Alexandro della Spina* : invention des *lunettes de vue*.</span>
-<span style="color: #0066cc">&#8226; &#8776;1550</span> | <span style="color: #0066cc">inventions des *lunettes terrestres et astronomiques*.</span>
-<span style="color: #0066cc">&#8226; [1514;1570]</span> | <span style="color: #0066cc">*Barbaro* améliore chambre obscure grâce à lentille convergente (*ancêtre appareils photo*).</span>
-<span style="color: #0066cc">&#8226; 1590</span> | <span style="color: #0066cc">invention du *microscope* attribuée à *Janssen*</span>
-<span style="color: #0066cc">&#8226; 1608</span> | <span style="color: #0066cc">*Lippershey et Metius* : invention du *télescope*</span>
-<span style="color: #993333">&#8226; 1621 et 1637</span> | <span style="color: #993333">*Snell* et *Descartes* : *loi de la réfraction*.</span>
-<span style="color: #993333">&#8226; [1601;1665]</span> | <span style="color: #993333">*Fermat* : énoncé du *principe de Fermat*, base conceptuelle de l'optique géométrique.</span>
-<span style="color: #0066cc">&#8226; de 1816 et 1824</span> | <span style="color: #0066cc">Niépce : mise au point de l'appareil photographique et première photographie. Le défi était "chimique", pour fixer l'image.</span>
-<span style="color: #0066cc">&#8226; de 1840 à1850]</span> | <span style="color: #0066cc">*Démonstration expérimentale* de la *réflexion totale* à l'interface de deux matériaux trasnparents.</span>
-<span style="color: #0066cc">&#8226; 1852</span> | <span style="color: #0066cc">*Charrière et Désormeaux : premiers endoscopes* pour usages médicaux</span>
-<span style="color: #0066cc">&#8226; 1927</span> | <span style="color: #0066cc">*Baird et Hansell*: brevet utilisation *fibre optique pour transmission d'images* de télévision.</span>
-<span style="color: #0066cc">&#8226; 1970</span> | <span style="color: #0066cc">Corning (entreprise) : développe & commercialise *première fibre optique pour télécommunications*.</span>
-
-
-
-#### Geometrical optics : position in the optical sciences
-
-![](sciences_optique_rays.en.jpg)