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Progressive Addition Lenses 159

Fig. 11.38: First progressive addition lens

Fig. 11.39: The “Physiological” progressive addition lens

inevitable astigmatism in the lens periphery. American Optical Ultravue,
Rodenstock Progressive R, Sola Graduate etc., were in this category. Other
manufacturer took a different approach, reducing the amount of unwanted
astigmatism in the periphery by spreading it more widely in the lens.
Truvision Omni of American Optical became popular. Zeiss Gradal HS
placed special emphasis on the concept of the lens asymmetry and
comfortable binocular vision.
Soon multi-design concept was introduced in Varilux Infinity in 1988
– the third generation progressive. The multi-design used district designs
to match the wearers changing needs with advancing presbyopia. Multi-
design concept refers to the change of power progression profile with