All lenses were made of glass, except those that were made of plastic, of course.  Although as they were so few, they seem to be hardly worth a mention.  But they do deserve a very honourable mention in the history of lenses, particularly the very first plastic lenses pioneered by a manufacturer in the UK, Combined Optical Industries Ltd., affectionately known as COIL.  The spectacle lenses were known as “Igard” lenses and dominated the UK plastic spectacle lens market for many years and were exported to several countries overseas.  The lenses were made from Polymethylmethacrylate (pmma) commonly known as “perspex”.  This material had many advantages over others, introduced later, but had one disadvantage, it was “softer” and even the later “Igard Luxe” (about 20% harder) was less resistant to surface damage than newer CR39 material, (Allyldiglycolcarbonate). 

CR39, (Columbia Resins,expriment no 39) initially produced in th U.S.A., took over the European market and was launched by Silor of France as “Orma 1000”.  Silor later merged with spectacle manufacturer Société des Lunetières. aka Essel to form the now world famous ESSILOR,  which produces probably the widest range of top quality lenses in the world, notably the “Varilux” lens in its various forms.  Arguably the lens which is to varifocal lenses what Hoover is to vacuum cleaners.   

Tags: CR39, CR39 glasses, essilor, glasses material

This entry was posted on Monday, December 22nd, 2008 at 8:38 pm and is filed under Eye Care, Glasses, Lenses. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.