Articles liés à Astigmatism (eye): Refractive error, Eye, Refraction,...

Astigmatism (eye): Refractive error, Eye, Refraction, Retina, Contact lens, Cylindrical lens, Refractive surgery, Cornea, Lens (anatomy) - Couverture souple

 
9786133736276: Astigmatism (eye): Refractive error, Eye, Refraction, Retina, Contact lens, Cylindrical lens, Refractive surgery, Cornea, Lens (anatomy)
Couverture souple
ISBN 10 : 6133736275 ISBN 13 : 9786133736276
Editeur : Alphascript Publishing, 2010

Synopsis

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. There are two types of astigmatism: regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses. Regular astigmatism arising from either the cornea or crystalline lens can be corrected by a toric lens. A toric surface resembles a section of the surface of an American football or a doughnut where there are two regular radii, one smaller than another. This optical shape gives rise to regular astigmatism in the eye. The first spectacle lenses that corrected astigmatism were made in Philadelphia in 1841.

Les informations fournies dans la section « Synopsis » peuvent faire référence à une autre édition de ce titre.

Présentation de l'éditeur

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. There are two types of astigmatism: regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses. Regular astigmatism arising from either the cornea or crystalline lens can be corrected by a toric lens. A toric surface resembles a section of the surface of an American football or a doughnut where there are two regular radii, one smaller than another. This optical shape gives rise to regular astigmatism in the eye. The first spectacle lenses that corrected astigmatism were made in Philadelphia in 1841.

Les informations fournies dans la section « A propos du livre » peuvent faire référence à une autre édition de ce titre.

Éditeur
Alphascript Publishing
Date d'édition
2010
Langue
anglais
ISBN 10 
6133736275
ISBN 13 
9786133736276
Reliure
Broché
Nombre de pages
80
Éditeur
Miller Frederic P., Vandome Agnes F., McBrewster John
Coordonnées du fabricant
non disponible
Personne responsable
non disponible

Autres éditions populaires du même titre

9786130681616: Astigmatism

Edition présentée

ISBN 10 :  6130681615 ISBN 13 :  9786130681616
Editeur : Alphascript Publishing, 2010
Couverture souple