Varifocal glasses have been around for many years now and there are currently around 10 million wearers in the UK. These lenses work by combining three distances (Far, intermediate and near) into one lens to enable patients to only have to carry around 1 pair of glasses in order to be able to see at every distance. These multifocal lenses are known in the industry as Progressive additional lenses and the first ever patent for these varifocal lenses was granted in the UK to Own Aves in 1907, however, this design never became commercially available. These lenses were not available to the public until Stewart Duke Elder, a Scottish ophthalmologist, came up with the world’s first commercially available varifocal lens in 1922.
Early Varifocal lens designs were very crude making wearing varifocal glasses quite an uncomfortable experience for many. The first modern design of the progressive additional lens was the ‘Varilux’ lens which was developed by Bernard Maitenaz whose company ‘Essel’ later became part of the Essilor group in 1959. Bernard was not really interested in the development of a progressive lens but wanted to improve the manufacturing process of mineral lenses. The ‘Varilux’ range of varifocal lenses are now the most widely sold lenses in the World today due to their clever lens designs, global marketing strategy and affordable price point.
Varifocal glasses wearers in the past have always suffered from the disadvantages of ‘power progression’ within the lens which creates aberration (distortions) around the edges of the varifocal. For some people these distortions outweigh the convenience and practicality of having one pair of glasses for all distances and early designs of varifocal glasses had a very poor adaption rate among new wearers. This has all changed in recent years with new varifocal lens technology advancing very rapidly due to the amount of investment in design research being made by all the major lens manufactures such as Carl Zeiss, Nikon and Essilor. The very latest breakthrough in varifocal lenses is the new design of ‘free form’ lenses which incorporate front and back surfacing of each lens to allow for a more natural visual experience through the lens. This new method of manufacturing varifocal lenses has seen a vast improvement of successful adaption among new varifocal wearers and, in turn, has made varifocals a much more attractive alternative to carrying tow pairs of spectacles around. One thing is for sure, varifocals are here to stay and as lens technology progresses so will the demand for these lenses by the spectacle wearing population.
Jim Romand is a specialist prescription lens consultant and dispensing optician who has worked in the industry for over 25 years. After qualifying as an SMC Tech at the london college of optometry in 1985, He has since worked as a Lab consultant for many high street opticians chains within the UK. He currently works as a specialist prescription lens technician producing Varifocal Spectacles for the UK market.