The Definitive Guide To Choosing the Right Lenses

Choosing what material your lenses will be made with is most likely the first decision you’ll need to make after you’ve picked out your favorite frames. Here are the options you’ll have:

Polycarbonate lenses

Polycarbonate is light yet a strong type of plastic that was first developed for the military and is now the standard material used in safety glasses, sports glasses, and children’s prescription eyeglasses because it is both impacts resistant and “virtually unbreakable,” according to The Vision Council. It’s also a good choice for rimless glasses, where the lenses aren’t protected within a frame.

Another type of lightweight, impact-resistant lens is called Trivex, which is a urethane-based monomer that provides sharper, crisper optics than polycarbonate lenses, due to the way they are molded.

Plastic lenses

One of the most popular materials used to make lenses is CR-39, a thermal-cured plastic developed in the 1940s. It’s lightweight, inexpensive, and works well with all prescriptions.

High-index plastic lenses

Driven by the demand for even lighter-weight lenses than traditional plastic, many manufacturers now offer high-index plastic lenses in a range of thicknesses. A detailed description of each index is listed below.

Glass lenses

Glass is no longer a common option for lenses because of the danger it poses if they break. Also, though they do provide crystal-clear optics, they are twice as heavy as plastic.

Though each person’s prescription may be unique, vision needs fall into a few basic categories:

1. Myopia — also called “nearsightedness,” vision becomes blurred when looking at distant objects.
2. Hyperopia — also called “farsightedness,” vision is blurry up-close and possibly fuzzy in the distance.
3. Astigmatism — blurred or double-vision at any distance.
4. Presbyopia — blurred vision when reading or needing to see something up close.

Your diagnosis and needs will determine the type of lenses that work best for you.

Single-Vision Distance

One of the most common types of prescription glasses is single-vision distance, which is prescribed if you are diagnosed with hyperopia, that is, nearsightedness. If you look at your written prescription, it will begin with a negative number and your lenses will curve inward (concave) to correct your vision.

Single-Vision Reading

Many people require reading glasses as they get older. You can tell whether you need them by noticing if you are squinting when reading or need to pull what you are working on farther away for it to be clear. Single-vision reading glasses are quite inexpensive on their own, and you can find them in most drug stores, grocery stores, or anywhere you find prescription glasses online. These lenses curve outward (convex) and have a (+) before the magnification number on the prescription and the inside temple of the frames.

If your middle and distance vision is good, you only require single-vision reading glasses to use when you need them. If you require correction for middle or distance vision, however, you’ll need to choose between getting progressive or bifocal lenses. In that case, you will need to wear your glasses regularly.

Progressive Lenses

Progressive or “multifocal” lenses have become very popular because they can address multiple fields of vision seamlessly, and can be fine-tuned to fit very unique vision needs. Each field of vision correction blends into the next without any visible line present on the lenses. The distance correction is at the top of the lens and the reading correction is at the bottom. The middle portion can have vision correction or none at all, depending on the prescription. Progressives can take a little while to get used to and can feel a bit disorienting at first. Your brain will adjust to them within a week or so and after that, it will feel like second nature when you put them on.

Bifocal Lenses

Bifocals address two correction areas: reading and distance. There is a visible line or rounded area for the reading portion, but there are several options for where that are begins and how big it is. Some start at the mid-point and cover the entire bottom half of the lens, while others only cover the bottom third or quarter. If the bifocals are used for detail work rather than reading, they may have the magnification area in a small circle towards the bottom of the lens.

Choosing which kind (or kinds) of lens coating to use on your new glasses can be confusing, especially if you aren’t sure what the benefits are and whether they are cost-effective for your situation. These detailed descriptions should help you make that decision with confidence.

Anti-Scratch Coating

Because plastic and polycarbonate lenses are extremely susceptible to scuffs and scratches, an anti-scratch coating is not only recommended but necessary if you want your glasses to stand up to everyday use and normal wear-and-tear. A factory-applied anti-scratch coating can make your lenses as durable as original glass lenses were while maintaining their lightweight and impact-resistant qualities. Ask your optician or online provider about purchasing an extra warranty against scratches if you tend to leave your glasses around without a case or are buying them for children.

Anti-Reflective Coating

An anti-reflective (AR) coating is also a worthwhile option to add to your prescription lenses. It reduces glare and eliminates reflection, which is important especially while driving at night or operating equipment. Reflections are distracting for you and others when making eye contact and in photographs. The coating allows the lenses to blend in with your face and become virtually invisible. AR coating is essential if you choose higher-index lenses since they refract light more efficiently, they will also be more reflective unless you add the coating.

Light-Adjusting Coating

Often known by the brand name, “Transitions,” light-adjusting coating (also called photochromic treatment) causes your lenses to darken automatically in response to UV light. When you return to normal lighting indoors, the lenses return to clear or almost clear. The coating has improved quite a bit over the years and is barely perceptible now, compared to the tell-tale tint of the treated lenses when they were first introduced. The coating can be applied to any type of lens and any prescription.

Color Tint Coating

For the most part, color tinting is added to sunglasses, unless you want a particularly unique look to your regular prescription. Beyond fashion, however, color tinting is used to aid or enhance certain visual effects. For example, gray tinting offers sun shading without affecting color perception, yellow increases contrast for driving, hunting, or sports, and blue blocks UV and scatters blue light emissions.  Color tinting can be added along with mirrored coating for a unique, fashionable look.

Gradient Tint Coating

The gradient-tint coating is used on larger-framed sunglasses so it can span the whole range of dark-to-light. They are darker at the top and progressively lighten towards the bottom, which is a nice feature if you’re reading outdoors. More than just practical, they offer a fashionable look and complement many frame styles, particularly aviator styles.

Polarized Coating

Polarized lenses are great for filtering horizontal light while still letting vertical light in, resulting in clearer, higher-contrast optics. They are excellent at eliminating glare, which makes them great for driving and outdoor sports activities.

Mirrored Tint Coating

Besides just looking cool, mirrored lenses reflect light away from the eyes, offering a different type of UV protection. The coating can be combined with color-tinted lenses and can be applied as a full mirror or with a more translucent effect. Full-mirrored lenses prevent anyone else from seeing your eyes, which can make conversation a little awkward and uncomfortable for some people.

Water-repellent Coating

The water-repellent coating keeps water droplets from sticking to the lens which is helpful if you spend a great deal of time outdoors in a variety of weather.

UV Protective Coating

UV coating is an expected feature of sunglasses, but it can be applied to regular prescription glasses as well. If you choose CR-39 plastic lenses, you need to add UV coating as an additional option. High-index lenses and polycarbonate lenses have UV protection built right into the lenses themselves.

Blue light blocking glasses are becoming a popular choice for computer and other digital equipment use, even if you normally don’t need a prescription. They protect against harmful UV light and scatter the blue light emissions that come from digitally lit screens. This reduces eye strain while allowing the beneficial blue-turquoise light to still come through.

Another choice you need to make when ordering your glasses is how thin and light you want your lenses to be.

1.5 Index — Standard Lens

Standard lenses are a good choice as long as you don’t have a very strong prescription. This is the type of lens included in the price of your prescription, so it is the least expensive option. Though lighter weight than glass lenses, they are the heaviest, thickest of the options you can choose from. Make sure you add a UV coating to these if you want that option since they are not already built into the lens material.

1.57 Index — Thin and Light Lens

These lenses are thinner and lighter than standard lenses and are appropriate for stronger prescriptions, including CYL corrections up to +/-3.00 and SPH corrections between +/-4.00 and +/-5.00.

1.59 Index — Polycarbonate Lens

Polycarbonate lenses are impact-resistant and come with a UV-protective coating and are recommended for use in rimless glasses, for children, or outdoor and sports use.

1.6 Index — Super-Thin Lens

If you have a strong prescription, a super-thin lens is a great option for you, especially if you have chosen lightweight, delicate frames. These lenses can handle SPH corrections from +/-4.25 to +/-6.75 and CYL corrections between +/-2.25 and +/-3.00.

1.67 Index — Ultra-Thin Lens

The best feature of ultra-thin lenses is that they don’t make your eyes look distorted if you have a strong prescription — eliminating the “coke-bottle-glasses” look.

1.74 Index — As Thin as Possible Lens

If you have a super-strong prescription, you may want to go for 1.74 index lenses in your frames. These are ultra-light and thin, which counterbalance even the highest-powered vision correction.