Progressive Lenses Vs. Tri-Focals

Not all eyeglass lenses are created equally. Various lenses are designed to improve the wearer's reading vision and correct presbyopia, the age-related loss of near vision. Progressive lenses and trifocals are both available to correct vision.

Progressive Lenses

• Progressive lenses offer clear vision without image jumps eyeglasses on notebook image by Alexander Maksimov from Fotolia.com

  Also called "no-line bifocals," progressive lenses gradually increase a wearer's vision from the immediate viewing area to the distant viewing area. These multifocal lenses are not segmented like traditional bifocals. They are comprised of three areas: a large top-distance area, a narrow progressive transitional corridor and a medium-sized reading area. Because there are no lines between the segments, wearers have clear, natural vision at all distances without image jumps.

Trifocals

• Trifocals are segmented into three lenses. One segment corrects distance viewing. The second lens corrects near viewing. The third segment provides 50 percent more magnification for the near-viewing segment.Trifocals dramatically improve the wearer's vision relating to computer use and driving

Safety Concerns

• Both types of lenses have safety issues. smiling woman image by Marylin from Fotolia.com

  Wearers of progressive lenses experience blurriness in the peripheral zones to their far left or far right. While offering improved sight, trifocal wearers must be aware of safety issues associated with these lenses. Vision may blur while looking down without tilting the head down, especially in poorly lit areas. In these instances, opticians suggest wearing a pair of single-focus glasses while walking.