{"id":10219,"date":"2021-01-28T22:40:04","date_gmt":"2021-01-28T22:40:04","guid":{"rendered":"https:\/\/groupeastronomiespa.be\/astrogas\/mesure-de-la-focale-dun-miroir\/"},"modified":"2025-06-08T22:44:48","modified_gmt":"2025-06-08T20:44:48","slug":"mesure-de-la-focale-dun-miroir","status":"publish","type":"post","link":"https:\/\/groupeastronomiespa.be\/astrogas\/mesure-de-la-focale-dun-miroir\/","title":{"rendered":"Mesure de la focale d’un miroir"},"content":{"rendered":"

Une m\u00e9thode r\u00e9pandue sur internet consiste \u00e0 r\u00e9fl\u00e9chir un objet lumineux sur une cible, et d’utiliser la formule:<\/p>\n

1\/f = 1\/u + 1\/v,
\nu et v \u00e9tant respectivement la distance du miroir \u00e0 la cible et du miroir \u00e0 l’objet.<\/p>\n

Il nous faut une distance de la source au miroir assez looongue.<\/p>\n

\"\"<\/a><\/p>\n

Pour me faciliter la t\u00e2che, j’ai ajust\u00e9 le miroir vers la cible au moyen d’un laser.<\/p>\n

\"\"<\/a><\/p>\n

Le miroir est mont\u00e9 sur un banc ajustable.<\/p>\n

\"\"<\/a><\/p>\n

A la source, un croisillon est mont\u00e9 sur une lampe \u00e0 led plane.<\/p>\n

\"\"<\/a><\/p>\n

Il faut le focaliser sur la cible, et c’est facile.<\/p>\n

Il est conseill\u00e9 de faire plusieurs mesures et de les moyenner.
\nJ’ai trouv\u00e9 que la m\u00e9thode se r\u00e9v\u00e8le assez r\u00e9p\u00e9titive.
\nVoici les r\u00e9sultats pour 7 mesures faites avec un miroir de 320mm:
\n1893 mm
\n1892 mm
\n1892 mm
\n1892 mm
\n1891 mm
\n1894 mm
\n1892 mm<\/p>\n

Alexandre
\n2021-Jan-27<\/p>\n\n\n

\n \n
\n \n
\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n <\/div>\n \n
\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n
\n \n\n
<\/div>\n <\/div>\n <\/div>\n<\/div>\n \n\n
\n Veuillez voter<\/span>\n <\/div>\n <\/div>\n","protected":false},"excerpt":{"rendered":"

Une m\u00e9thode r\u00e9pandue sur internet consiste \u00e0 r\u00e9fl\u00e9chir un objet lumineux sur une cible, et d’utiliser la formule: 1\/f = 1\/u + 1\/v, u et v \u00e9tant respectivement la distance du miroir \u00e0 la cible et du miroir \u00e0 l’objet. Il nous faut une distance de la source au miroir assez looongue. Pour me faciliter […]<\/p>\n","protected":false},"author":16,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[3],"tags":[],"class_list":["post-10219","post","type-post","status-publish","format-standard","hentry","category-astrobricolage"],"_links":{"self":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts\/10219","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/users\/16"}],"replies":[{"embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/comments?post=10219"}],"version-history":[{"count":1,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts\/10219\/revisions"}],"predecessor-version":[{"id":11463,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/posts\/10219\/revisions\/11463"}],"wp:attachment":[{"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/media?parent=10219"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/categories?post=10219"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/groupeastronomiespa.be\/astrogas\/wp-json\/wp\/v2\/tags?post=10219"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}