While frames undoubtedly play a vital role in the aesthetic appeal of eyewear, it’s the lenses that ultimately determine the functionality and effectiveness of the eyeglasses or sunglasses. They correct vision, enhance visual clarity, and protect the eyes from harmful UV rays, glare, and other environmental factors.
When it comes to selecting the right lenses for your eyeglasses or sunglasses, there are several factors to consider. Should you choose single-vision or bifocal lenses? How about polarized or anti-reflective lenses?
In this article, we’ll break down all the different types of lenses and explain how each can benefit your visual experience.
Types of Lenses for Glasses
Let’s begin by discussing the different types of prescription lenses available for glasses.
Single-vision lenses are the most common type of prescription lenses used in eyeglasses. As the name suggests, these lenses have a single prescription power throughout the entire lens.
They’re typically used to correct nearsightedness, farsightedness, or astigmatism, and are an excellent option for individuals who require correction for a single vision problem.
Bifocal lenses are a popular type of prescription eyeglasses lens with two distinct areas of vision correction, making them a good choice for those with both nearsightedness and farsightedness.
The upper portion of the lens is designed for distance vision, while the lower half-moon segments are designed for near vision, such as reading. The transition between the two areas of the lens is visible, with a distinct line running across the top of reading area.
Trifocal lenses are a type of prescription eyeglasses lens that have three distinct areas of vision correction. These are a convenient solution for individuals who require near, intermediate, and distance vision correction.
Similar to bifocals, trifocals have an added intermediate segment on top of the reading segment.
The upper portion of the lens is designed for distance vision, the middle portion for intermediate vision, such as computer work, and the lower portion for near vision, such as reading.
Like bifocals, trifocal lenses have visible lines that separate the different areas of vision correction.
Progressive lenses, also known as no-line multifocal lenses, are a type of prescription eyeglasses lens that provides a gradual transition between distance, intermediate, and near vision correction without having any visible lines on the lenses.
This makes them a popular choice for people who require multiple levels of vision correction, but want a more seamless, natural-looking transition between the different areas of the lens.
Photochromic lenses are a type of eyeglasses lens that automatically adjusts to changing light conditions. The lenses darken in bright sunlight (that is, to UV exposure) and lighten in indoor or low-light conditions.
This makes them ideal for those who spend a lot of time outdoors and don’t want to switch between different pairs of eyewear.
It’s important to note that because vehicles have a UV filter built into the windshield and windows, photochromic lenses will not provide a dark tint for driving.
Types of Coatings for Glasses and Sunglasses
Just like choosing the right prescription lenses for your needs, selecting the right coating for your eyeglasses or sunglasses is crucial to ensure optimal vision and eye protection. Let’s explore the different types of coatings available and their unique benefits.
Anti-reflective coating is a popular type of coating for eyeglasses lenses that reduces reflective light. The coating works by allowing more light to pass through the lens and reach your eye (instead of light bouncing off the lens). This results in having little to no reflections on the front or back surfaces of your lenses.
Anti-reflective coatings work to enhance visual acuity, as you won’t be as distracted by reflections on your lenses. They also make the lenses more aesthetically pleasing by reducing the appearance of reflections on the surface of the lens.
This type of lens coating is especially helpful for night driving or working on a computer.
Anti-reflective coating isn’t typically seen on sunglasses lenses. Why? Because the whole point of sunglasses is to block light from reaching your eye—and anti-reflective coating allows more light to reach your eye.
Note: Many people use the terms “anti-reflective” and “anti-glare” interchangeably, but there’s a difference between the two. Anti-glare lenses more accurately describe polarized lenses, which are designed to block out bright light waves like glare from the sun (more on this shortly).
Scratch-resistant lenses are a type of eyeglasses and sunglasses lens that’s designed to resist scratches and other types of surface damage. The lenses are treated with a special coating that makes them more durable and resistant to everyday wear and tear.
Scratch-resistant lenses are a particularly good choice for individuals who lead an active lifestyle or work in environments that expose their eyewear to potential damage. But they’re beneficial for anyone, as lenses can get scratched just from being handled, dropped, or tossed in a purse.
Nothing is scratch-proof. Even with this coating, scratches are still possible, so it’s important to properly clean your glasses by protecting your glasses from scratches and keeping them in a case when you’re not wearing them.
All Privé Revaux glasses come with scratch-resistant and impact-resistant lenses.
Most sunglass lenses are designed to protect the eyes from the sun’s harmful ultraviolet (UV) rays. The lenses are treated with a special coating that blocks out UV radiation, which can cause long-term damage to the eyes, such as cataracts and macular degeneration.
UV lenses are especially important for individuals who spend a lot of time outdoors, as they provide protection against both UVA and UVB rays.
All Privé Revaux glasses offer 100% UVA/UVB protection.
Polarized lenses (aka anti-glare sun lenses) are designed to minimize glare off reflective surfaces by filtering out horizontal light waves. (Think of the light bouncing off the windows of a car in front of you in traffic - very distracting!)
Polarized lenses in sunglasses serve a crucial function of reducing glare from the sun. However, they also offer several additional benefits, including enhancing color vibrancy, increasing contrast, and reducing eye strain.
These features make them an excellent option for people who spend considerable time outdoors—especially on lakes or oceans—as they provide clear vision while reducing glare and other potential vision disturbances.
Blue Light Blocking Lenses
With the widespread use of electronic devices in our daily lives, it’s common to spend long hours staring at screens. Blue light blocking lenses are an excellent option for those looking to minimize the adverse effects of blue light on their eyes.
Blue light is a type of high-energy visible light emitted by electronic devices such as computers, smartphones, televisions, and even the sun.
Overexposure to blue light is said to cause eye strain and headaches, and disrupt the natural sleep cycle. Some research even suggests overexposure to blue light can damage retinal cells and cause vision problems.[*]
Blue light blocking lenses feature a specialized coating that reduces the amount of blue light that reaches your eyes. For those who spend a lot of time working on computers or using electronic devices, blue light blocking lenses are a must. Learn more about the benefits of blue light glasses.
Many brands of blue light blocking glasses have a yellow tint, but Privé Revaux’s are virtually transparent, giving you all the protection you need with a crystal-clear view and appearance.
At Privé Revaux, we offer a variety of non-prescription blue light glasses.
And most of our sunglasses and all of our reading glasses come with built-in blue light blocking protection.
Hydrophobic lenses, which are available for both eyeglasses and sunglasses, repel water and prevent it from sticking to the surface of the lens.
This specialized coating helps to keep the lenses clear and free from water droplets, which can impair vision and cause discomfort.
Hydrophobic lenses are an ideal option for individuals who spend a lot of time outdoors or engage in water sports, as they help to maintain clear vision even in wet and rainy conditions.
Oleophobic lenses repel oil and prevent fingerprints and smudges from sticking to the surface of the lens.
This specialized coating helps to keep the lenses clean and clear, improving vision and reducing the need for frequent cleaning. Oleophobic lenses are great for those who use their glasses frequently or engage in activities that expose their eyewear to oils and fingerprints, such as cooking.
Anti-fog lenses, which are available for both eyeglasses and sunglasses, are treated with a specialized coating that prevents fogging and condensation from forming on the surface of the lens.
These lenses help maintain clear vision and prevent the need for constant wiping or cleaning. Anti-fog lenses are a good choice for those who engage in activities that cause heat and moisture buildup, such as exercising, cooking, or working in humid environments. They’re also helpful for those who wear face masks.
Mirror lenses are a type of sunglasses lens that have a reflective mirror-like appearance.
These lenses are an excellent choice for individuals who want to make a fashion statement or engage in outdoor activities, as they help reduce glare and shield against bright light.
You’ve likely noticed that sunglasses lenses come in various colors, from blue to purple to green. These are called tints, and each color provides various visual benefits.
For example, brown lens sunglasses help provide a brighter, clearer view in lower-light conditions, while blue lens sunglasses work to enhance color perception and see contours around objects more clearly.
Grey lenses are popular because they block out a lot of light in bright conditions.
Learn more about how different lens tints can benefit your visual experience here.
Types of Glasses Lens Materials
While all glasses lenses might look the same, they can be manufactured using different materials. Let’s break these down:
Today, plastic is the most common material used to manufacture eyeglasses and sunglasses lenses. This lightweight and durable material offers excellent optical clarity and can be easily customized to fit various prescriptions and frame styles.
Plastic lenses are available in different types, each with unique properties. The most common types include:
- CR-39: These plastic lenses are affordable, lightweight, and provide excellent optical quality.
- Polycarbonate: This type of plastic lens has all of the same qualities of CR-39, but are far more impact-resistant. In fact, polycarbonate is the same material used for bullet-proof glass! Polycarbonate also allows for special coatings to be easily applied to the lenses.
- Acrylic: Acrylic is a transparent plastic material known for its exceptional strength, stiffness, and optical clarity. Acrylic lenses have become a standard feature in many off-the-shelf reading glasses due to their affordability and durability. Privé Revaux’s reading glasses and blue light glasses are made with blue light blocking acrylic lenses.
- High-index lenses: This type of plastic lens has a higher refractive index than standard plastic lenses. This means they can correct more severe refractive errors while maintaining a thinner and lighter lens profile.
Triacetate cellulose lenses are made from a plastic polymer material called cellulose acetate. This material is produced by chemically modifying natural cellulose fiber to increase its durability, strength, and resistance to heat and moisture.
TAC lenses offer optical quality comparable to glass and impact resistance comparable to polycarbonate, making them a top choice for sunglasses.
Despite their plastic-like appearance and texture, TAC lenses are constructed from specialized film layers that work together to provide a high-quality optical experience.
Glass lenses were once the primary material used to manufacture eyeglass lenses, but have since been replaced by plastic lenses due to safety and comfort concerns.
Glass lenses offer excellent optical clarity and scratch resistance, but are heavy, brittle, and prone to shattering upon impact.
Despite these drawbacks, glass lenses are still available for certain applications, such as high-power prescriptions or specialized lens coatings.
Due to their limitations and potential safety risks, glass lenses are not a recommended option for everyday eyeglasses.
A Final Word on Types of Lenses
Choosing the right lenses for your glasses or sunglasses is essential for optimal vision correction and eye protection. By considering your visual needs and lifestyle, you can select the lens materials and coatings that provide the most significant benefits for your vision and eye health.
With a wide variety of lens options and styles, you’re sure to discover the perfect eyewear to fit your lifestyle and personal style. Find your fit today!