The Best Glasses Guide: Eyeglass Lenses and Coatings


What Are Glasses Made Of?

We often refer to spectacles as glasses, but if you’ve owned a pair of modern glasses, you’ve almost certainly noticed that they aren’t actually made of glass.

And, if you’ve always thought that glasses are made of glass, well…

The truth is technology has come a long way and today almost all modern lenses are not made of glass at all, instead we use different types of plastics.

Why plastic?

I mean, sure, if you drop a pair of glass glasses then you can say “goodbye” to that pair of spectacles, but we only make lenses with plastic because it’s cheap and easy to mass produce, right?

The truth may surprise you.

Plastic Lenses —Better Than Glass?

The reality is that, in fact, plastic lenses have many important attributes that make them much more appropriate for prescription eyeglasses than actual glass.

Like What?” I hear you say.

First off, and most obviously: They are impact resistant and shatter proof which makes them much more suited for outdoor activities and sports.

Plastic lenses are also much lighter than glass, and this relieves much of the pressure that a heavy glass lenses can put on your nose.

This ties in to what’s referred to as a lens’ “index”. Plastic lenses come in a variety of different indexes; different indexes tell you how much it focuses the your eyesight, and with plastic lenses you can get a way higher index without worrying about having to wear really heavy glasses. So a high index plastic lenses can be much thinner than standard glass lenses; plastic lenses are comfier, lighter and and thinner.

Plastic lenses aren’t just more convenient, they’re more aesthetically appealing, too.


Types of Glasses: Eyeglass Lenses

Even among plastic lenses, there are several options to consider:

  • Aspheric

    You can tell an aspheric lense from how the curvature of its front surface gradually changes from the center of the lens out to the edge. Aspheric lenses provide correction for small distortions in vision; they’re a great choice if your vision isn’t perfect but doesn’t leave you completely blind without a pair of spectacles.

    As a side benefit, they are also typically thinner and lighter than most other lenses.

  • Polarized

    Most people think of non-prescription sunglasses when they hear about polarized lenses; but prescription sunglasses can be polarized, too.

    These lenses reduce glare reflected off surfaces and make images sharper and clearer. People with light-sensitive eyes, such as post-cataract surgery patients might wear polarized lenses indoors. Most polarized lenses provide UV protection, which is important to maintaining healthy eye sight.

  • Photochromic

    Photochromic lenses (most notably marketed under the brand name Transitions) automatically darken to protect your eyes when exposed to ultraviolet (UV) light. The newest version of Transitions now darkens in just over a minute and is also available in polarized.

  • Bifocal & Trifocal

    A Bifocal lens is what you want if you suffer from both near- and far-sightedness. Trifocal lenses take that even further; they’re for people who have trouble seeing things clearly from a few feet away.

    On top of that, trifocal lenses add to your range of vision and widen your field of view, which is handy for when you’re driving or or working on a computer.

  • Hi-Index

    A high-tech lens design which cuts down on material thickness even more than aspheric lenses. These are ideal for people with strong prescriptions, especially if you want to avoid the discomfort of wearing very heavy glasses.

  • Progressive

    Progressive lenses, like bifocals and trifocals improve your vision at close, intermediate, and long distances. They have the added advantage of not having lines between lens sections; which counts a lot for style if that’s what you’re worried about.


Types of Lens Coatings

Once you’ve decided on the right type of lenses, you can choose from a selection of different coatings to customize your glasses to suit your specific needs:

  • Anti-Glare or Anti-Reflective Coatings

    This coating significantly reduces the light reflected from the front and back surface of the lens. Good quality anti-glare coatings minimize halos from lights at night, cut down on glare from computer monitors and other digital displays as well as decrease glare from overhead fluorescent lighting. 

  • Blue Light Reduction Coatings

    A type of coating that reduces digital eye strain by reducing your exposure to blue light from smartphones, tablets, computer screens, televisions, energy-efficient lighting, and the sun. This attractive, near-clear coating also optimizes visual performance, improves visual comfort, enhances your appearance, and extends the life of your lenses.

  • Scratch Resistant Coatings

    While there’s no way to make your lenses completely scratch-proof, a scratch-resistant coating prevents most abrasions from damaging your lenses (and interfering with your vision). Scratch-resistant coatings protect your investment and minimize every day wear and tear.

  • UV Protection Coatings

    Overexposure to ultraviolet rays can cause serious eye problems. A UV protection coating coating paired with polarized or photochromic lenses can completely block UVA and UVB rays.

There are so many great lens options available to create a pair of glasses that fits your unique visual environment. 

Let our skilled opticians guide you through the options to find the lens material and design that will give you both clear vision and smart appearance. 

Midtown Optometry is a specialist eye care clinic in Santa Cruz, California.