Page 5 - Cahier-Progressive Lenses-GB.indd

Introduction introduction Since their introduction by Essilor in 1959, progressive With the expected growth in the population, particularly lenses have gained world-wide acceptance as the most amongst the elderly, presbyopes will become even more suitable correction for presbyopia. Because they provide numerous in the years to come. The market for lenses to clear, comfortable, natural vision at all distances, they correct presbyopia will continue to grow and the repla- have gradually replaced bifocal lenses and are becoming cement of bifocal and single vision lenses by progressive used more and more instead of single vision lenses for lenses is certain to follow. Progressive lenses still have a near. good future. Today, one in four of the world population is presbyopic, This volume of the Essilor Ophthalmic Optics Lens Files some 1.5 billion people. Less than half of these pres- series reviews the basic physiological and technical byopes are corrected, but where they are, about 25% concepts behind progressive lenses from their first Progressive lenses are fitted with progressive lenses, less than 25% with appearance to the most recent developments. bifocal lenses and around 50% with single vision lenses. Although the precise distribution varies from country to country, the use of progressive lenses is seen to be on the increase everywhere. Fig. 1 : Presbyopes : a growing population 5 Copyright © 2006 ESSILOR ACADEMY EUROPE, 13 rue Moreau, 75012 Paris, France - All rights reserved – Do not copy or distribute.