Types of Glasses Lenses

Glasses lenses fall into six main categories based on how they correct vision and what conditions they're designed for. Single-vision lenses correct one distance zone. Bifocals and progressives combine multiple zones for people who need reading correction alongside distance. Reading lenses are magnification-only. Photochromic and polarized lenses add environmental adaptations for light and glare.

Here's a side-by-side view of the six lens types and where each fits best:

These aren't mutually exclusive. Most lens types can be combined with coatings, tints, and specialty treatments. The base type is the starting point; the coatings are what make the pair genuinely comfortable to wear every day.

Single-vision lenses correct vision at one distance. They're the most common lens type worldwide and the standard for anyone who needs correction for either distance vision, intermediate vision, or reading, but not more than one at the same time.

Single-vision lenses work well for people under 40 who typically need correction for one distance only. Nearsighted (myopic) wearers get single-vision distance lenses. Farsighted (hyperopic) wearers may get single-vision reading lenses. Someone with astigmatism only gets single-vision toric lenses.

If your prescription only requires one distance correction and you don't experience trouble focusing at other distances yet, single-vision is the right choice. It's the most affordable option and offers the sharpest, most uniform vision across the lens surface, since there are no transitions between zones.

Single-vision lenses can also be prescribed specifically for computer use (single-vision intermediate) or reading (single-vision near), which some people prefer over progressives when the task doesn't require switching distances.

Bifocal lenses combine two corrective zones with a visible dividing line: distance vision on top, reading vision on the bottom. They've been around for over 200 years and remain a legitimate choice for people who want clear boundaries between vision zones.

Bifocals work well for older adults who need both distance and reading correction and prefer the predictability of a defined line. Many long-time bifocal wearers don't want to switch to progressives because they've adapted to the line and find the sharp transition helpful for knowing exactly where each zone starts.

The main tradeoff: bifocals are more affordable and easier to adapt to initially, but they're visibly "aged" (the line is a giveaway) and lack the intermediate zone (arm's length, roughly where computer screens sit). Progressives blend the zones invisibly and add intermediate correction, but they cost more and take longer to adapt to. For readers over 60 who don't spend heavy time at intermediate distances, bifocals still make sense. Get the full breakdown and comparison in our guide on progressive vs. bifocal lenses.

Progressive lenses combine distance, intermediate, and reading correction in a single lens with no visible lines between zones. They're the most popular multifocal choice today and the standard recommendation for most adults over 40 who need reading correction alongside their distance prescription.

The upper portion of the lens holds your distance prescription. The lower portion holds your reading prescription. Between them, a progressive corridor smoothly transitions through intermediate strengths, giving you clear vision at arm's length (crucial for screen work) as well as distance and near. Because the transitions are gradual, there's no visible line marking the zones.

Progressives are the default modern choice for people over 40 with presbyopia (age-related loss of near focus) who also need distance correction. They eliminate the need to switch between multiple pairs of glasses. If you find yourself needing reading glasses in addition to your regular pair, progressives combine both.

Progressive lenses have a small area of peripheral distortion on the sides of the lens, where the transition between zones creates a slight visual warp. Most wearers adapt within two weeks. Some don't. If you're highly sensitive to peripheral vision changes, spend significant time in activities requiring wide peripheral awareness (some sports, certain professions), or have a very strong prescription, progressives may take longer to adapt to or may not be the right fit.

If you've tried progressives and struggled to adapt after 4-6 weeks, bifocals or dedicated single-vision reading glasses may serve you better. Some people prefer keeping a single-vision distance pair for driving and a separate reading pair for close work, avoiding the compromise inherent in any multifocal design.

Progressives are the most flexible modern lens for age-related vision changes because they cover all three distances in one pair. When optometrists recommend them, it's not always about upsell; it's often because they genuinely solve the multi-distance problem better than the alternatives. That said, the recommendation should match your actual daily needs. If you don't spend much time at intermediate distances, cheaper options may serve you just as well.

Reading lenses (often called "readers") are single-vision lenses designed only for close-up tasks like reading, sewing, or hobby work. They magnify text and near objects without correcting distance vision at all.

Reading lenses come in standard diopter strengths, typically from +1.00 to +3.50 in 0.25 increments. The right strength depends on your age, the distance you hold reading material, and any underlying vision issues. Most people over 40 start around +1.25 to +1.50 and progress stronger over the following decades.

Readers make sense for people who otherwise have good distance vision but need help with close-up work. They're inexpensive, easy to keep multiple pairs of, and available over-the-counter (though a prescription pair from an optometrist will be more accurate than a generic store pair). Not suitable as a primary daily wear if you need distance correction; use progressives or bifocals instead.

Photochromic lenses darken automatically in sunlight and clear indoors, giving you one pair that works both inside and outside. Transitions is the most widely known brand of photochromic lens, though the terms are often used interchangeably in casual conversation

Photochromic lenses contain molecules (typically silver halide or organic dyes) that change shape when exposed to UV light. The shape change makes them absorb more visible light, which darkens the lens. When UV light stops hitting them (indoors), the molecules revert and the lens clears. The process takes 30 seconds to a minute in each direction. Read more on photochromic lenses in the NIH's study on the effects of photochromic lenses on visual performance.

Photochromic is the general lens category. Transitions is a specific brand made by Transitions Optical (owned by Essilor). All Transitions lenses are photochromic, but not all photochromic lenses are Transitions brand. Other manufacturers make competing photochromic lenses with similar technology. Transitions is often the default because they were first to popularize the tech, but other photochromic options exist at similar quality tiers. For the full comparison, check out our guide on photochromic vs Transitions lenses.

Photochromic glasses excel for people who move between indoor and outdoor environments often and don't want to swap pairs or wear prescription sunglasses over their prescription lenses. Main limitation: car windshields block most UV light, which means photochromic lenses don't darken effectively while driving. If driving is your primary outdoor use case, prescription sunglasses may serve you better than photochromic.

Polarized lenses have a filter that blocks horizontal light waves, which cause the glare you see reflecting off water, snow, roads, and car hoods. The result is sharper contrast, less eye strain, and clearer vision in bright conditions. Polarized lenses are primarily used in sunglasses rather than prescription eyewear.

Sunlight scatters in all directions when it hits reflective surfaces. Horizontally-oriented light waves are what your eye perceives as glare. A polarized filter is oriented vertically inside the lens, blocking the horizontal waves and letting only the vertical waves through. The visual impact is immediate: glare disappears and colors look richer.

Polarized lenses are especially valuable for driving (cuts road and car-hood glare), water sports (see through the water surface), snow activities (cuts snow glare), and any outdoor use where reflective surfaces cause vision problems. For general daily wear in variable conditions, polarized is a legitimate upgrade over standard tinted lenses.

Real polarized lenses will darken significantly or black out completely when rotated 90 degrees in front of an LCD screen (phone, laptop, monitor). If the lens tint doesn't change as you rotate, the polarization claim is false. This 5-second test confirms genuine polarization before you commit.

Polarized lenses can make some LCD screens (car dashboards, some phones, certain digital displays) harder to read at specific angles. Frequent drivers who rely on digital instrument panels should test polarized sunglasses in their specific car before committing.

Coatings aren't a base lens type; they're layers added to any of the six base lens types. In practice, coatings often matter more than the base type itself, because they determine whether your lenses stay clear, resist damage, and stay comfortable to wear for years.

Anti-reflective (AR) coating reduces reflections on both the front and back surfaces of the lens. The visible effect: no distracting glare from lights, screens, or camera flashes; other people can see your eyes rather than lens reflections in photos. AR coating is standard on quality prescription lenses and should be included, not upsold.

Anti-scratch coating hardens the lens surface to resist damage from dust, cleaning cloths, and accidental contact. It's not scratch-proof (nothing is), but it extends usable lens life significantly. Also standard on quality lenses.

Blue light coating filters a portion of high-energy visible light from screens. Current research suggests blue light doesn't cause permanent eye damage, but blue light coatings may reduce symptoms of digital eye strain (dry eyes, headaches) during long screen sessions. Worth considering if you spend 6+ hours a day on screens; less critical if you don't.

UV coating blocks 100% of UV rays that could damage your eyes over time. Standard on sunglasses (UV400). Also available on clear prescription lenses for people who spend significant time outdoors. Photochromic lenses have UV protection built in.

Mirror coating reflects a portion of visible light off the lens surface, giving sunglasses their distinctive mirrored look. Beyond the aesthetic, mirror coatings reduce the total light entering the lens, which is useful for very bright conditions (snow, high altitude, tropical sun). Available in silver, gold, blue, green, red, and other tints.

Kraywoods includes anti-reflective and anti-scratch coatings as standard on every prescription lens, applied in our Canadian optical lab, rather than upselling them as optional extras. Blue light and mirror coatings are available as add-ons when they fit the buyer's needs.

With six lens types plus coating options, the choice can feel overwhelming. Three quick questions narrow it down for most buyers.

• Under 40: Single-vision lenses in your prescription strength, plus appropriate coatings. Most people don't need multifocal correction until presbyopia sets in.

• 40-60: Progressives are the default recommendation as reading correction becomes necessary. Bifocals if you prefer defined zones or prioritize cost.

• 60+: Progressives or bifocals depending on preference. Consider dedicated reading glasses as a backup pair for extended reading sessions.

• Screen work primarily: Consider single-vision intermediate lenses (for a dedicated computer pair) or progressives for full-range use.

• Driving primarily: Prescription sunglasses (polarized) plus a clear pair for other times. Photochromic can work but doesn't darken behind car windshields.

• Outdoor activities: Polarized prescription sunglasses, or photochromic if you move between indoor and outdoor often.

• Reading and close work: Dedicated readers or progressives, depending on whether you also need distance correction.

• Mild prescriptions (under +/-3.00): Any lens type works. Standard-index materials are fine.

• Moderate prescriptions (+/-3.00 to +/-6.00): Consider high-index lens material to keep lenses thin and light.

• Strong prescriptions (+/-6.00 and higher): High-index lens material becomes essential. Progressive lenses may have a smaller usable zone; ask your optometrist about premium progressive designs or check out our high index lenses guide.

• Six main lens types cover most needs: single-vision, bifocal, progressive, reading, photochromic, and polarized.

• Coatings layer on any base type and often matter more than the base type itself. Anti-reflective and anti-scratch should be standard, not upsold.

• Progressives are the default for adults over 40 who need reading correction alongside their distance prescription. Bifocals still make sense if you prefer defined zones.

• Photochromic lenses don't darken well in cars because windshields block UV. For heavy drivers, prescription sunglasses are usually the better choice.

• Polarized lenses test easily against an LCD screen (rotate 90 degrees). Fake polarization is common in cheap sunglasses.

• Age, primary use case, and prescription strength are the three questions that narrow the choice quickly.

Lens choice matters more than most eyewear buyers realize because the lens is where your glasses actually do their work. Frames hold the lens in place; coatings determine long-term comfort; but the lens type itself is what determines whether your glasses correct your vision the way you actually use them.

Explore polarized sunglasses and prescription glasses with premium coatings included as standard, or reading glasses for magnification-only lenses. For deeper single-topic coverage on specific lens technologies, head to the Lens Types & Technology hub.