Transitions Signature Flat Top 28 Polycarbonate Composite lenses are now available exclusively from Younger Optics, according to an email from Younger.Its photochromic Trivex layer uses Chromea 7 technology. The lens, which has an 1.59 index like polycarbonate, reportedly has superb segment cosmetics.
Transitions Optical uses a proprietary process to make polycarbonate lenses photochromic. While this process works for a variety of lens geometries, it is not compatible with segmented, or flat-top lenses such as bifocals and trifocals. This has meant that traditionally, a polycarbonate FT28 lens has not been available with Transitions® technology. Until now. Younger Optics and Transitions Optical have developed a polycarbonate composite lens that incorporates a thin photochromic front surface bifocal layer made of Trivex — resulting in a lens delivering Transitions Signature performance in a product that is surfaced, polished, edged and dispensed just like a clear polycarbonate lens.