title: Spectacles: past, present, and future.
abstract: The history of spectacles is reviewed with particular attention to recent developments in lens materials. The author advocates the use of polycarbonate, a high resin plastic, because of its strength, high refractive index, light weight, and resistance to fogging.
mesh_terms: D003365:Costs and Cost Analysis; D005060:Europe; D005139:Eyeglasses / Q000266:history*; D005260:Female; D005898:Glass; D006115:Greece; D049668:History, 15th Century; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D049690:History, Ancient; D049691:History, Medieval; D006801:Humans; D007909:Lenses; D008297:Male; D010969:Plastics; D011076:Polycarboxylate Cement; D011092:Polyethylene Glycols; D012384:Rome; D014481:United States
chemical_list: D010969:Plastics; D011076:Polycarboxylate Cement; C028827:CR 39; C005506:polycarbonate; D011092:Polyethylene Glycols