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French Varilux Logo. Varilux is a brand name belonging to Essilor International, a producer of corrective lenses.The first version of the lens was invented by Bernard Maitenaz and released in 1959, and was the first modern [clarification needed] progressive lens to correct presbyopia.
Bernard Maitenaz, patented Varilux in 1953, and the product was introduced in 1959 by Société des Lunetiers (now Essilor). The first Varilux lenses' surface structure was however still close to a bifocal lens, with an upper, aberration-free half of the surface for far vision and a rather large "segment" for clear near vision.
The progressive addition lens (PAL, also commonly called a no-line or varifocal lens) eliminates the line in bi/tri-focals and is very complex in its profile. PALs are a continuously variable parametric surface that begins using one spherical surface base curve and ends at another, with the radius of curvature continuously varying as the ...
Essilor International is a French multinational corporation specialized in the design, manufacture and sale of ophthalmic lenses, optical equipment and instruments. [ 1 ] [ 2 ] It is the world's largest manufacturer of ophthalmic lenses.
The Kilfitt 36–82 mm/2.8 Zoomar lens introduced in 1959 was the first varifocal lens in regular production for still 35mm photography. [8] The first modern film zoom lens, the Pan-Cinor, was designed around 1950 by Roger Cuvillier, a French engineer working for SOM-Berthiot. It had an optical compensation zoom system.
The change in the subject size is a significant problem in video and true parfocal designs are needed for higher quality video work. Varifocal lenses can be used for image display as well as capture, and Meta's Reality Labs has confirmed developing a varifocal display for virtual reality. [2] A varifocal lens. Left image is at 2.8 mm, in focus.
Back applied for a patent in 1946 for a "Varifocal lens for cameras", which described the theory of its operation, using five sets of lenses: ordered from the object to the film, these were the front lens, variator, erector, compensator, and relay, with the variator and compensator mechanically fixed to each other and moving along the optical ...
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