The introduction of the first bifocal lenses by ZEISS as long ago as 1952 represented a real revolution at the time. In the recent years, however, the popularity of bifocals has considerably decreased due to the constant improvement in the quality of progressive lenses.
While a large number of segment shapes existed in the past, the type with a curved top is now the most common in most countries and is indicated in the product name by a "C" (curved). Fewer reflections result on the curved surface than on the straight edge of an S segment (S = straight). Today’s bifocal lenses from ZEISS therefore provide wearers with improved cosmetic benefits and enhanced functionality.