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11

Progressive Addition Lenses

The concept of progressive addition lens has been around since 1907 when
the first patent on progressive power lens was published by Owen Ave.
The early progressive lenses were rather crude in design. Varilux 1 was
introduced by Essilor in France in the year 1959 and since then progressive
addition lens have gained worldwide acceptance as the most performing
ophthalmic lens for the correction of presbyopia because they provide
comfortable vision at all distances. They are successfully and
advantageously replacing single vision and bifocal lenses. Growing
popularity of progressive addition lenses has stimulated the search for
advances in design and manufacturing technology of the progressive lenses.
This has enabled progressive addition lenses to develop from the early
“hard” designs requiring extended patient adaptation time to current “state
of the art” softer asymmetric design to the individually customized
progressive lenses. Today over 150 progressive addition lens designs are
in the market.
Progressive addition lenses (Fig. 11.1) are one piece lenses that vary
gradually in surface curvature from a minimum value in the upper distance

Fig. 11.1: Progressive addition lens