Eyewear A To Z

Glasses glossary,optical terms,optical glossary – Eyewear A To Z Glossary


Unlocking the World of Eyewear Terminology


‘s commonly seen on eyeglass prescriptions, indicating the extra magnification power for your glasses.

Amblyopia, also known as “lazy eye,” is when your eyes can’t see clearly. It usually happens during childhood when the nerve connecting your brain to your vision doesn’t develop properly. As a result, your eye doesn’t learn to see like it should.

Anti-reflective coating is this special type of coating that’s put on lenses. It’s great because it reduces annoying glare and reflections on the lens surface, making your vision clear by letting more light through. If you spend a lot of time on electronic devices, trust me, this coating is a game-changer. And guess what? It also keeps your lenses clean by repelling water and smudges. So not only will you see better, but you’ll look sharp too!

The arm, aka the temple, is the main part that runs alongside your head and keeps your glasses in place. Pretty neat, huh?
It’s an eye condition that gives you blurry vision. If you don’t fix it, it can give you headaches too. It keeps you from seeing things super clear. But don’t worry, you can fix it by getting the right glasses!

Aviator frames are a total classic when it comes to eyewear. With their teardrop-shaped lenses and sleek metal frames, they were initially made for pilots but have now become a timeless fashion statement.

“axis” is what eye doctors use in prescriptions to show the angle of astigmatism. It’s measured in degrees to make sure the correction matches your eye perfectly.

Acetate, the fashion-forward choice for eyewear frames, combines flexibility, durability, and vibrant colors. This type of plastic is renowned for transforming ordinary glasses into stylish eye-catchers!
anti-fog coatings help keep eyeglass lenses from fogging up, especially when you transition between different temperatures. It’s super useful for those who wear glasses with face masks!


base curve is usually mentioned on contact lens prescriptions. It ensures a proper fit, and the measurements typically range between 8 and 10.

Blue light is this energetic, short-wavelength light from digital screens, smartphones, and other electronic devices. If you’re exposed to it for too long, it can cause digital eye strain. The good news though, is that eyeglasses coated with blue light-blocking technology can help reduce those effects.

Bifocals are eyeglass lenses with two sections dedicated to near and distant vision. They’re often prescribed for folks who need correction for both reading and distance in one pair of glasses.
The bridge of eyeglasses is the part that sits on your nose. It’s super important because it holds the weight of the glasses and keeps them comfy. Bridges come in various shapes and designs to fit different face shapes.
Browline frames are a total classic when it comes to eyewear. They’ve got this bold upper frame that looks like eyebrows! These frames first became a hit back in the 1950s and are still a super stylish choice today.

The base curve is all about the curvature of eyeglass lenses. A flatter base curve = lower number, while more curved lenses = higher number. It’s all about how the lenses fit into the frame and how they look on your face.


Know that people with color blindness perceive colors differently? It’s pretty common, with varying degrees from mild to severe. Interestingly, those with mild color blindness may not even realize it! On the other hand, those with severe color blindness can only see black and white. And guess what? It affects men more than women. Stats show that around 8% of men experience color blindness, while only 0.5% of women are affected.

You’ll often see it on eyeglass prescriptions as CYL. It’s the lens power needed to fix astigmatism.

Coatings are like magic layers added to eyeglass lenses to make them perform better and last longer. You’ve got anti-reflective coatings to beat the glare, anti-scratch coatings to fend off scratches, and UV coatings to keep those harmful rays at bay.

Crystals are like top-notch lens material, known for their amazing clarity and scratch resistance. That’s why you often find them in super fancy eyeglasses, because they’re all about that optical excellence!

Cut-eye frames are this relaxed eyewear style with those upswept outer corners, giving them that cat’s eye shape. Since the 1950s, they’ve been a fashion icon – known for that bold and glamorous look.
Color tint is all about adding a particular hue to eyeglass lenses. It’s like jazzing it up for fashion or tackling specific visual needs, like dialing down that brightness sensitivity.

Clip-on sunglasses are like cool sidekicks for your regular eyeglasses. They make it super easy to switch between prescription eyeglasses and sunglasses, so you don’t need a separate pair of shades.

Comfort frames are eyeglass frames made from a cool mix of metal and plastic. These frames give you a nice combo of style and durability.


Diopter is a measurement unit that tells how much a lens can bend light. Positive diopters help with farsightedness (hyperopia), while negative diopters fix nearsightedness (myopia).

You’ll usually see the diameter measurements written on your contact lens prescriptions. It’s just the width of the contact lenses, measured in millimeters.

Care professionals sometimes use special drops to dilate your pupils, allowing them to get a closer look at your retina. It means your pupils are widened temporarily for a better eye examination. The only downside is that you might not see things clearly for a few hours until your pupils go back to normal.

Doble bridge frames rock an awesome look with two horizontal bars across the nose, giving you extra stability. Not to mention, they’re known for being super durable and boasting a classic aesthetic.

Depth perception is all about gauging the relative distance of objects in three-dimensional space. Having correctly corrected vision, often with glasses, is crucial for nailing that accurate depth perception.

Digital eye strain, or computer vision syndrome, is the discomfort and vision issues that happen when you spend too much time staring at screens. Wearing computer glasses with anti-reflective coatings can totally help relieve these symptoms.

Diopter adjustment is all about customizing your eyeglass prescription for certain types of eyewear. Whether it’s reading glasses or sports goggles, it lets you fine-tune the magnification to suit your specific needs. So you can see things just the way you like!

Doul-purpose frames are like the superheroes of eyeglasses! They rock prescription and sunglass lenses with handy magnetic clip-ons for different lighting conditions. So versatile!

Distortion in eyewear refers to funky visual aberrations or irregularities that mess with your clear and accurate vision. Opting for top-notch lenses and precise prescriptions helps minimize that wonky distortion.


You get older, your eyes age too. So, your prescription changes along with them. It’s important to keep your prescription up to date, you know?

When you spend long hours staring at a screen or driving, your eyes can tire out. It’s called eyestrain. If you constantly deal with this, it’s a good idea to get your eyes and vision checked. You might need glasses to ease the strain. Here at Muunel, we’ve got you covered with our lens technology that effectively eliminates eyestrain using our special blue light protection technology.

An eye exam is a thorough check-up of your vision and eye health. It’s done by either an optometrist or ophthalmologist and includes different tests to assess your visual acuity, prescription requirements, and overall eye well-being.
Thickness is a measurement that shows how thick or thin the lenses are at the edges, especially for high-prescription lenses. Thanks to advances in lens technology, like high-index materials, edge thickness has been reduced. This makes glasses look cooler and more comfy too!

Eye Care of your eyeglasses means giving them the TLC they deserve! To make sure they stay in top shape and always provide clear vision, simply clean them regularly using a microfiber cloth and gentle solutions. This way, you can keep your lenses smudge-free and your frames looking great!


If you have farsightedness, you won’t see things up close clearly, but distant objects will be visible. Hyperopia is the fancy word for this condition.

Are these cool eyewear that you can rock over your regular prescription glasses. They give you extra sun protection and fight off that annoying glare, making them perfect for all your outdoor adventures.

Frame size refers to the overall dimensions of the eyeglass frames, including the width of the lenses, the height of the lenses, and the length of the temple arms. Frame size is crucial for ensuring that the glasses fit your face properly.

Face shape has a big impact on what eyeglass frame styles will suit you best. We’ve got round, oval, square, heart-shaped, and diamond-shaped faces. Picking the right frames can really level up your facial aesthetics.

Flex hinges are like the MVPs of eyeglass frames. They let the temples (the arms) flex outward, giving you a snug and comfy fit. 🕶️ Perfect for active peeps or those with broader heads.

Frame materials are what they use to make eyeglass frames. You’ll find common materials like acetate, metal, plastic, and titanium. Each material has its properties, like how tough it is, how heavy it is, and its style. It’s all about finding the right kind of frames for you!


Glare is all about that annoying, blinding brightness or light reflections that can bug you when driving or hanging out outside. Here’s the good news: polarized lenses do a great job cutting glare down. 🕶️

Gradient lenses are eyeglass or sunglass lenses that have this cool fading effect – darker at the top and lighter at the bottom. They’re all the rage for fashion and keeping those peepers protected from the sun!

The term “grind” in eyewear is all about shaping and polishing the edges of lenses to make sure they fit perfectly into the frame. Lens grinding ensures that the lenses line up just right with your eyes.

Glazing is the process of fitting new lenses into an existing eyeglass frame. It allows you to update your prescription without replacing the entire frame.


High-index lenses are used for thin plastic s that are considered suitable for some higher prescriptions. These lenses are only recommended for adults that are 16+.

Hydrophobic, or farsightedness, is a pretty common vision condition where you can see far away objects more clearly than close ones. It happens when light entering your eye lands behind the retina instead of on it. Don’t worry, though, you can fix hyperopia with either glasses or contact lenses.

It is a medical term used for farsightedness.

Hinges are the joints that connect the frames’ temples (arms) to the front part of the eyeglasses. They allow the temples to fold inward, making putting on and removing your glasses easier. Hinges come in various designs, including standard, spring-loaded, and flexible hinges.

Holographic lenses use advanced technology to create 3D-like visual effects on the lens surface. While primarily decorative, they can add a unique and stylish element to your eyeglasses.

Hydrophobic coatings are applied to eyeglass lenses so they can repel water and moisture. This keeps the lenses clear and prevents rain droplets from messing up your vision. Super helpful during rainy or humid days!


Interpupillary distance (IPD), or the measurement between the centers of your pupils, is super important! It ensures that your eyeglass lenses sit right in front of your eyes for clear vision and maximum comfort. So, it’s a big deal!

Impact-resistant lenses are designed to withstand physical impact and are often used in safety glasses and sports eyewear. These lenses reduce the risk of eye injuries by offering enhanced durability and protection.

The index of refraction is this numerical value that tells you how much a material can bend or refract light. In eyewear, we use it to talk about how well the material can bend light to fix your vision. The higher the index, the thinner and lighter the materials, which is great for high-prescription lenses.

Itchy eyes can be a common complaint among eyeglass wearers. It may result from allergies, dryness, or irritation caused by eyeglass materials. Using hypoallergenic frame materials and lubricating eye drops can help alleviate itchiness.

Inlays are decorative or functional elements embedded into the frames of eyeglasses. They can add style or uniqueness to your eyewear, such as gemstone inlays for a touch of luxury or functional nose pad inlays for enhanced comfort.


A keyhole bridge is a bridge design for eyeglasses that resembles the shape of an old-fashioned keyhole. It’s known for its distinctive appearance and can add a vintage or retro touch to your eyewear.

Keratoconus is this eye condition where the cornea becomes thin and bulges like a cone. It can mess with your vision, and you might need special contact lenses or glasses to fix vision problems caused by it.


Lens material is basically the stuff that makes eyeglass lenses. You know, the common ones are glass, plastic, and polycarbonate. Each material has its own special traits like weight, thickness, and how well it can handle impacts.

Lens tint refers to the color or shading applied to eyeglass lenses. Tinted lenses can serve various purposes, such as reducing glare, enhancing contrast, or providing UV protection. Popular tints include gray, brown, and green.

Ultraviolet (UV) protection is crucial for eye health. Many eyeglass lenses have UV-blocking coatings that shield your eyes from harmful UV rays. This protection can help reduce the risk of eye conditions related to UV exposure.

Certain lens materials may not be compatible with specific coatings or treatments. It’s essential to consider compatibility when selecting lens material and desired coatings to ensure optimal performance and longevity.


Monovision is often prescribed in contains. You can use monovision to use one lens for distance and one lens for far vision.

Myopia, commonly known as nearsightedness, is an eye condition where distant objects appear blurry while close-up objects can be seen clearly. It is typically corrected with concave lenses, which help focus distant light properly onto the retina.

Multifocal lenses are like having multiple vision corrections in one lens, making life easier for those who need help with both reading and distance vision. Just one pair of glasses does it all! 👓

Monocular vision refers to the ability to see clearly with only one eye. It can be the result of vision loss in one eye or may be a preference for using one eye for specific tasks.


Nose pads are small cushioned pieces attached to the bridge of eyeglasses that rest on your nose. They help distribute the weight of the glasses evenly and enhance comfort. Nose pads come in various materials, including silicone and acetate, to suit different preferences.

Nose bridge fit refers to how well the bridge of the glasses matches the shape and size of your nose. A proper nose bridge fit ensures that the glasses stay securely in place and do not slide down your nose.

Nose pad arms are the extensions of the eyeglass frame that connect to the nose pads. They play a role in adjusting the fit and positioning of the glasses on your face.

If you suffer from nearsightedness, be able to see districts.


O.D. stands for Oculus dexter. The word often appears on your prescription, meaning right eye in Latin.

It is the abbreviation of Oculus Sinister. In Latin, it means the left eye. It is often written on your prescription.

An optometrist is a healthcare pro who’s trained to check, diagnose, and treat different eye conditions and vision issues. They can hook you up with glasses, and contacts, and provide all the essential eye care you need.

An ophthalmologist is a medical doctor specializing in eye care and eye surgery. They can diagnose and treat eye diseases, perform eye surgeries, and provide comprehensive eye care.


Plano lenses have no prescription power and are used for cosmetic or protective purposes. They are often employed in non-prescription sunglasses or safety glasses.

P.D. stands for pupillary distance. It is the distance between your pupils. It helps you in aligning your lenses to fit the frames you choose. Your pupillary distance can be measured in many ways. There is a device used for this purpose, known as the pupillometer.

Progressive lenses are multi foxes used to correct multiple eye-related problems in a single lens. It means thupdatecan convert your whole field of vision without the need to change glasses frequently.

Photochromic lenses, often transition lenses, are eyeglass lenses that darken in response to UV exposure and lighten indoors or at night. They provide convenience by eliminating switching between regular glasses and sunglasses.

Polarized lenses are specially designed to reduce glare caused by reflections from surfaces like water, roads, and snow. They enhance visual clarity and comfort, making them an excellent choice for outdoor activities.

A prescription is a written document from an eye care pro (optometrist or ophthalmologist) that tells you the vision correction needed for your eyeglasses or contact lenses. It has details like sphere (Sph), cylinder (Cyl), axis, and pupillary distance.

Prism correction is prescribed when there is a misalignment of the eyes, causing double vision or discomfort. Prismatic lenses help align the eyes correctly, allowing for single, fused vision.


Quad-focal lenses are specialized multifocal lenses that provide four different prescription zones within a single lens. They are designed for individuals with complex vision needs, often requiring near, intermediate, and distance corrections and additional correction for specific tasks.

Quick-release hinges are a convenient feature found on some eyeglass frames. They allow for easy removal and attachment of the temples (arms) to the frame. This feature can be particularly useful when changing the temples or for compact storage.

Quartz lenses are a type of high-quality eyeglass lens material known for its exceptional optical clarity and scratch resistance. They are often used in premium eyewear to provide superior vision correction and lens durability.

Quick-tint lenses are photochromic lenses that darken in response to UV light exposure. They provide the convenience of transitioning from clear to tinted lenses outdoors, reducing the need for separate sunglasses.


Refrraction is how eyecare pros figure out your eyeglass prescription. They measure how light bends when it passes through your cornea and lens. The prescription they come up with tells you the lens power you need to fix your vision.

The retina is the light-sensing tissue in your eyes. To make things easier for you, thilookof your vision like a camera and retina as its photographic film.

Refractive errors are common vision problems that occur when the shape of the eye prevents light from focusing directly on the retina. Common refractive errors include myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.

The reading area, also known as the reading segment, is the portion of multifocal lenses (e.g., bifocals or progressives) designed specifically for near vision tasks, like reading or close-up work.


When you need to create super accurate progressive lenses, you need to use segment height. The vertical measurements in millimeters tell the lab where to start progression.

Single vision lenses are used to correct one field vision. It means that you patently correct a single eye-related problem using single vision lenses.

Sunglasses are protective eyewear designed to shield your eyes from the sun’s harmful ultraviolet (UV) rays. They come in various styles, lens colors, and UV protection levels, offering both fashion and eye health benefits.

Semi-rimless frames have only a partial frame surrounding the lenses, typically on the top half. This design offers a minimalist and lightweight appearance while maintaining stability.

Spherical lenses have a uniform curve across their entire surface. They are commonly used to correct nearsightedness, farsightedness, and astigmatism. These lenses have the same prescription power in all directions.


We are surrounded by ultraviolet light. Primary the main source of U.V. light, but it is also emitted from several electronic devices that we use, such as computers, televisions, LEDs, and other electronics.

UV protection in eyewear refers to lenses that block ultraviolet (UV) rays from the sun. Exposure to UV rays can harm your eyes and increase the risk of conditions like cataracts and macular degeneration. UV-protective coatings on lenses help shield your eyes from these harmful rays.

Unifocal lenses, also known as single-vision lenses, have a single prescription power throughout the entire lens. They are commonly prescribed for individuals who need correction for one specific vision need, such as nearsightedness or farsightedness.

Ultra-thin lenses are designed to be thinner and lighter than standard lenses, making them more aesthetically pleasing and comfortable to wear, especially for individuals with high prescriptions. They are often made from high-index materials.

UVC protection refers to the blocking of UVC rays, which are the most dangerous type of ultraviolet radiation. While the Earth’s atmosphere largely absorbs UVC rays, specialized coatings on eyewear lenses can provide an additional layer of protection.


Vision refers to the ability to see and interpret visual information. Clear vision is essential for daily activities, and eyeglasses play a crucial role in correcting and enhancing vision for individuals with refractive errors.

Visual acuity measures the sharpness and clarity of your vision. It is typically tested using an eye chart, and the results are expressed as a fraction, with 20/20 being considered normal vision.

Visual field refers to the total area that can be seen when the eyes are fixed on a central point. Glaucoma can affect the visual field, leading to loss of peripheral vision.

Ventilation refers to the design elements in eyeglasses that allow air to circulate the eyes. Proper ventilation helps reduce fogging and discomfort, especially in humid or active situations.


Wraparound frames are designed to curve around the sides of your face, providing enhanced protection from wind, sunlight, and debris. They are popular for sports and outdoor activities due to their added coverage and stability.

Wayfarer frames are a classic and timeless eyewear style known for their bold, square-shaped frames. They were popularized in the 1950s and have remained an iconic fashion choice ever since.

Welding goggles are specialized safety eyewear designed to protect the eyes from intense heat, sparks, and UV radiation during welding processes. They typically feature dark, tinted lenses for welding protection.

Wraparound sunglasses combine the style of regular sunglasses with the wraparound design of sports eyewear. They offer both fashion and practicality, providing excellent sun and glare protection.

Width measurement in eyewear refers to the horizontal measurement of the frame, typically from one temple hinge to the other. It helps determine if the frame is suitable for your face width.

Waterproof eyewear is designed to resist water and moisture, making them ideal for water-based activities like swimming or water sports. These glasses are specially sealed to prevent water from entering the frame.

Wire frames are eyeglass frames made from thin metal wires, offering a lightweight and minimalist design. They provide a subtle and sophisticated look, often favored by those who prefer understated styles.


Xylan coating is a specialized eyeglass lens treatment designed to repel water, oil, and dirt. It helps keep your lenses clean and clear, making them easier to maintain and improving your overall vision.


Yellow tinted lenses, also known as yellow or amber lenses, are designed to enhance contrast and reduce glare in low-light conditions. They are popular for activities like night driving and shooting sports.

Youth frames are eyeglass frames specifically designed to fit the more minor facial features of children and teenagers. These frames often come in fun colors and durable materials to withstand active lifestyles.

A yoke bridge is a specific type of eyeglass bridge design that resembles the shape of a yoke. It typically consists of a single, curved piece of metal or plastic that extends from one lens to the other, resting on the nose.

Yag laser (short for yttrium aluminum garnet laser) is used in certain eye surgeries, such as Yag laser capsulotomy to treat posterior capsule opacification after cataract surgery. It delivers precise energy to the eye’s tissues.

Monocular vision refers to the ability to see clearly with only one eye. It can be the result of vision loss in one eye or may be a preference for using one eye for specific tasks.

Metal frames are eyeglass frames constructed from materials like stainless steel, titanium, or aluminum. They are known for their durability, lightweight design, and sleek appearance.

Mirrored lenses have a reflective coating on the outer surface, reducing glare and offering a stylish, mirrored appearance. They are popular in sunglasses, particularly for outdoor activities.
A microfiber cloth is a small, soft fabric used to clean eyeglass lenses. It effectively removes smudges, fingerprints, and dirt without scratching the lenses.
Photochromic lenses, or transition lenses, automatically adjust their tint based on UV light exposure. They darken in bright sunlight and become clear indoors, providing convenience for varying light conditions.