Trifocal Glass Sun-Sensitive Lenses

Glass lenses for trifocal vision distance viewing also include sun-sensitive photochromatic technology, so the lenses will turn dark outside and light inside.  "Trifocal" means that the reading area has a half moon shape with a "flat top", in the bottom area of the lens.  The trifocal lens has three viewing areas, and the magnification area has two viewing areas, one for reading and one for intermediate distance.  The glass flat top 28 trifocal has a reading area that is 28mm wide at the top.  This glass lens is available in the following range: -6.75 to +4.00 sphere, -4.00 to +2.00 cylinder, and up to +3.00 add (prism and slab off excluded).