Glasses Despensing = تجهيز النظارات الطبية

Glasses Despensing = تجهيز النظارات الطبية

-

English
118 Pages

Description

The focus of this book is Glasses Despensing. It consists of Eleven Chapters. It’s discusses: (lenses Materials, Frame & Face Measurements, Optical Lenses, Measurements of Lens Curvature, Back Vertex Power & Distance, Prisms, Frame materials, Bifocal lenses, Absorptive lenses, Special Lens Designs and Fresnel prisms).

Subjects

Informations

Published by
Published 01 January 2013
Reads 0
EAN13 9796500152684
Language English
Document size 1 MB

Legal information: rental price per page €. This information is given for information only in accordance with current legislation.

Report a problem
 ﺰﻴﻬﺠﺗ  ﺔﻴﺒﻄﻟا تارﺎﻈﻨﻟا
Gl asses Despensi ng
Aseel O. Hamadeh Nisreen M. Al-Aqqad
2013
 ﺰﻴﻬﺠﺗ ﺔﻴﺒﻄﻟا تارﺎﻈﻨﻟا Gl asses Despensi ng
Contents ءاﺪﻫﻻا........................................................................................................1Chapter One: lenses Materials.............................................................3Glass lenses ................................................................................. 5 Plastic lenses ............................................................................... 8 Chapter Two: Frame & Face Measurements ...................................11Frame Measurements: ............................................................... 13 Face measurements and frame selection................................... 17 Chapter Three: Optical Lenses ..........................................................21Optical lenses ............................................................................ 23 Transposition............................................................................. 27 Designing a Lens to Change the Appearance of the Eye.......... 28 Chapter Four: Measurements of Lens Curvature ...........................31Chapter Five: Back Vertex Power & Distance.................................40Front & Back Vertex Power: .................................................... 41 Back vertex distance ................................................................. 43 Chapter Six: Prisms............................................................................46Chpter Seven: Frame Materials.........................................................53Chapter Eight: Bifocal & Multifocals Lenses...................................61Bifocal lenses: ........................................................................... 63 Multifocal Lenses...................................................................... 69 Progressive Lenses.................................................................... 73 Anisometropic Problems with Bifocal Glasses......................... 77 Chapter Nine: Absorptive Lenses & Lens Coatings..........................83Absorptive Lenses:.................................................................... 85 Lens Coatings............................................................................ 89 Chapter Ten: Special Lens Designs...................................................92Chapter Eleven: Low Vision Aids ......................................................97References .........................................................................................112
i
 ءاﺪﻫﻻا ﺎﻨﺋﺎﻗﺪﺻأ ﱃإ ,ﺎﻨﻴﺘﻠﺋﺎﻋ ﱃإ , بﺎﺘﻜﻟا اﺬﻫ ﴩﻧ ﰲ ﺎﻧﺪﻋﺎﺳ ﻦﻣ ﻞﻛ ﱃإ  بﺎﺘﻜﻟا اﺬﻫ يﺪﻬﻧ ﺎﻨﺑﻼﻃ ﱃإ ﺎﻀﻳأو ,ﻞﻤﻌﻟا ﰲ ﺎﻨﺋﻼﻣزو YÉÜ tÄÄ ã{ÉÅ {xÄÑxw âá àÉ ÑâÑÄ|á{ à{|á uÉÉ~? àÉ ÉâÜ ytÅ|Äç? yÉÜ ÉâÜ yÜ|xÇwá tÇw ÉâÜ ãÉÜ~ àxtÅ? tÄáÉ yÉÜ ÉâÜ áàâwxÇàá ãx z|yà à{|á uÉÉ~
-1-
Chapter One lenses Materials
-3-
Introduction
Optical lenses are defined as transparent component made from optical materials and cured to converge or diverge rays come from an object.
Functions of lenses: 1.Correct refractive errors 2.Protect the eye from harmful rays 3.Protect the eye from occupational hazards
Materials of optical lenses: 1.Glass 2.Plastic
Glass lenses
The development of optical glass: Glass has two properties that make it especially suitable for optical uses. It is transparent to the visible spectrum, and its surface may be worked so that they are also transparent and nonscattering. The invention of spectacles (if we define spectacle as two lenses mounted in a frame and used for the correction of ametropia) apparently occurred late in the thirteen century. The early lenses were apparently used only for the correction of presbyopia. However, during this time, good quality homogeneous optical glass was not available.
The critical properties of optical glass: 1. The refractive index (n) velocity of light in vacuum N=velocity of light in an optical medium 2. Dispersion expressed by Abbe number (v) 3. Specific gravity: weight of material per unit volume
Types of glass lenses: The termcrown andflint applied to optical glasses have lost their original meanings. -5-