History of Progressive Lens Development

History of Progressive Lens

Bi-focal eyeglasses are having two corrective lenses for distance and near. The lenses in the lower half are for near vision and lenses in the upper part are for far vision correction. Benjamin Franklin (the American statesman) was the inventor of bifocals. Bifocal eyeglasses are usually prescribed for presbyopia or approximately 40 years of age.

The story of the invention of the bifocal lens dates back to 1780s when Sir Benjamin Franklin was found deterioration in his vision and he found it difficult to switch far and near glasses. Around 1784, Benjamin Franklin cut two lenses in half and glued them together with a line extending across the entire width of the lens — one with a distance vision correction and one with a correction for near vision. It is now also called an Executive bifocal or straight-line bifocal. In this type of bifocal junction, the line was cosmetically unattractive and annoying.

In the 19th century the Franklin bifocal lens design was further refined. And the first fused bifocal was invented by John L. Borsch in the year 1899 but redesigned in 1908 and called the new ‘kryptok bifocal’.

In 1910, O’Conner produced a back surface grounded bifocal to improve chromatic aberrations which was found infused kryptok bifocal and provide a larger reading area. It is called as Ultex Bifocal.

In 1926, Univis Company introduced flat-top bifocal, which is called ‘D’ bifocal. In this bifocal unusable area at the top of the earlier (kryptok) bifocal was removed to decrease the prismatic image jump in vision.

In the 1950s, presbyopes were still using bifocals that divide the field of vision into two parts and were not looking for cosmetically attractive. A young French Optics and Mechanics engineer Bernard Maitenaz transformed the world of presbyopes by creating a lens that allows them to see at any distance without interruption.

 The story of the invention of the progressive lens starts when Bernard Maitenaz was studying at the École Supérieure d'Optique about the eye in his Optics and Mechanics engineering and thought that the eyes were magnificent organ which can see at all distances and have the capacity to see as 3D objects.

As the person’s eye ages and does not adjust/focus enough anymore, the only solution is to use a bifocal lens in front of it. He was in his twenties and full of enthusiasm so he thought to be a better solution. Being as an Optics and Mechanics engineer, he started as his project to calculated progressive surfaces of a lens, and prepared machines to produce it.

His objective was to achieve what he had imagined that is a lens with power in the lens varies progressively and allows compensating for this adjustment that disappears. This lens was a more physiological manner than with bifocal lenses without breaking the image.

He took 8 years to develop the first progressive lens called Varilux, which was launched in 1959. In 1972, his team introduced a modified progressive lens call Varilux 2, which was a fully aspheric lens. This lens was adopted world widely by presbyopes due to higher visual comfort.

Varilux (progressive lens) technologies are the innovation in the field of optics constantly involve addressing challenges in optical design, materials and the coating of lenses. Since 7 generations Varilux lens is continually improving and approaching a more and more natural vision. And now the Varilux S series is available with the latest technology and scientific progress.

Varilux is the lens available from the Essilor brand which is a leader in the optical market. Approximately 95% of Varilux wearer is very much satisfied around the world. Essilor brings different Varilux series:

Varilux Freedom 3.0
Varilux Comfort 3.0
Varilux Physio 3.0
Varilux E Series
Varilux X Series
Varilux S Series

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