Eyeglass lenses explained - a guide to lens types, materials and enhancements

Your Eye Exam Examined

Getting new glasses can be exciting. But choosing the right lenses for your new frames can be overwhelming. With so many choices, it is best to have a bit of background before shopping. To help you and your employees understand all the options, here are some of the most common lens types, materials and enhancements, along with some guidance for selecting the perfect pair.

Single bifocal and progressive lenses
Single vision

Single vision lenses are the most commonly prescribed lenses. They were developed for people who need to correct one field of vision, whether it's nearsightedness or farsightedness, and can be used to correct astigmatism.1 They have the same power of correction across the entire surface of the lens


See a line in the lens? Then it is a bifocal. Originally invented by Benjamin Franklin, bifocals include two different areas of vision correction divided by a distinct line that sits horizontally across the lens. The top portion of the lens is used for distance and the bottom portion is for close vision.


Known as no-line bifocals, progressive lenses are a perfect marriage of form and function. With no lines across the lens, others won’t even know you’re wearing a multi-focal lens. They provide a graduated range of vision that varies from seeing distance on the top to reading on the bottom. This is often the best lens for vision correction at all distances.


With trifocal lenses, you get three focal points in one lens. The lens powers start with close vision at the bottom of the lens, mid-vision through the middle and distance through the top. While still preferred by some, trifocals are becoming less common with more people opting for seamless, progressive lenses. 



Originally introduced in 1947, standard plastic lenses have become the most economical and commonly used material for eyeglass lenses. They’re more lightweight, thinner and more impact resistant than glass lenses. With excellent optical qualities, they’re often relatively inexpensive for value-conscious consumers.3


Originally created for helmet visors for the US Air Force, a polycarbonate lens is also impact resistant. It is thinner and lighter than plastic and provides 99% UV protection.4 Polycarbonate lenses are perfect for people with active lifestyles, children and those who need safety glasses. But they can scratch, so be sure to ask for a protection coating to help. 

High index

High-index is a super thin lens. More lightweight than polycarbonate, it offers the same degree of visual correction using less material. These lenses are best for individuals with strong prescriptions who want a thinner look.

Polarized lenses

Used in sunglasses, polarized lenses keep reflected light from reaching your eyes, resulting in less glare off of shiny surfaces like pavement and water. They also eliminate the sun’s glare, which helps reduce squinting and eyestrain and may help fight eye fatigue and headaches.5 Polarlized lenses are often recommended to patients with glaucoma6 and age-related macular degeneration.7

Anti-reflective lenses

While polarized lenses cut the glare reflecting off external objects, anti-reflective (AR) lenses have a coating that reduces internal reflections in the lens itself. It can improve night vision while also reducing headaches, blurred vision and watery eyes caused by eye strain.8 The coating also makes lenses nearly invisible. AR lenses are especially useful for people who do a lot of night driving or computer work.9

Blue light lenses
Blue Light

Blue light protection may either be incorporated into the lens material itself, or it may be added to a lens as a finishing coat. These special lens treatments provide protection from harmful high-energy blue light coming from digital devices. And they can help combat the effects this artificial light can cause, including blurry vision, difficulty focusing, dry and irritated eyes, headaches and even macular degeneration.10

Now that you’re in the know about available lens options, help your employees get up-to-speed before their next vision exam. Share our interactive vision guide, “Behind the lens” to take the mystery out of purchasing eyeglasses and help them buy the perfect pair. To learn more about prescription lenses available in your network, contact your EyeMed representative or visit eyemed.com


1 - AnnaMarie Houlis, “What are single vision lenses?,” Vision Center, Accessed November 2021.

2 - Gary Heiting, OD, “Bifocals and trifocals: solutions for short arms,” All About Vision, February 2019.

3 - Gary Heiting, OD, “Choosing the best lenses for your glasses,” All About Vision, October 2021.

4 - “Sunglasses and UV light: Q&A,” All About Vision, October 2021.

5 - Dr. Aizman, “Top 5 benefits of polarized sunglasses,” Empire Retina Consultants, Accessed November 2021.

6 - Anna Barden, “Glaucoma glasses may help manage symptoms,” All About Vision, June 2020.

7 - “Sunglasses and Mmcular degeneration,” WebRN—Macular Degeneration.com, Accessed November 2021.

8 - Michael Bayba, “What is anti-glare coating?,” Vision Center, October 2021.

9 - Gary Heiting, OD, “4 common lens coatings for glasses,” All About Vision, October 2021.

10 - “The effects of blue light and how to protect your eyes from it,” All About Vision, April 2021.