Trial set of progressive power multifocal lenses
 Catalogue Number: 2934 Trial set of progressive power multifocal lenses Category: Equipment Sub-Category: Trial lens case Corporation: HOYA CORPORATION Year Of Publication/Manufacture: c 1990 Time Period: 1940 to 1999 Place Of Publication/Manufacture: Japan Publisher/Manufacturer: Hoya Corporation Description Of Item: Set of 5 pairs (right and left eye) of progressive power multifocal lenses for purpose of trial, CR39 lenses in crystal shell rims, each with a short red handle with silver lettering designating R and L eye, the power of the addition from 1.00 D to 3.50 D and designated DESK, and marked HOYA on the reverse Historical Significance: Hoya Corporation is a large Japanese company, founded in 1941 and specialising in glass, ophthalmic and photographic lenses and optomechanical technologies. DESK means Hoyalux Desk a progressive power multifocal lens set designed for patients who require correction in the near and intermediate viewing zones. The first patent for a PAL was British Patent 15,735, granted to Owen Aves with a 1907 priority date, and included the manufacturing process. This design was never commercialised. Newbold appears to have designed a similar lens to Aves around 1913, and there is evidence to suggest that Duke Elder in 1922 developed the world's first commercially available PAL (Ultrifo) sold by "Gowlland of Montreal" that was based on an arrangement of aspherical surfaces. Irving Rips at Younger Optics developed the first commercially viable blended lens in 1955 called the Younger Seamless Bifocal. The Varilux & Carl Zeiss lenses were the first PALs of modern design. The former was developed by Bernard Maitenaz and patented in 1953, and introduced by the Societe des Lunetiers (which later became part of Essilor) in 1959. How Acquired: Donated by Estate of William Cooper, via Peter Lewis Date Acquired: April 2016 Condition: Very good Location: Archive room. West wall. Unit 5 Drawer 3 |