LENSES
Lens Materials: Standard Plastic, Polycarbonate and Glass Compared
Index only tells you thin or thick. Material — standard plastic, impact-resistant polycarbonate, glass — decides how durable, light and clear a lens actually is.
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Lenses
LENSES
Essilor Stellest: Myopia Control Lenses for Children
Stellest 1.59 Airwear for ages 6 to 18: 7,200,000d a pair, how H.A.L.T. works, what the 67% figure means, and when you don't need it yet.
LENSES
Essilor Eyezen: Lenses for Heavy Screen Use
Essilor Eyezen single-vision lenses for people on screens all day: light near-vision support, blue-violet light filtering. Prices from 1,780,000d a pair.
LENSES
How to Spot a Genuine Essilor Lens
Essilor is one of the most counterfeited lens brands, precisely because it's so well known. Five checks: packaging, hidden logo, warranty card, coating feel, authorised dealer.
LENSES
Varilux Comfort Max: All-Day Comfort Progressives
Essilor's comfort-leaning progressive lens. The difference shows up in your neck, not on a vision chart.
LENSES
Multifocal Lenses Explained: Essilor Varilux, Progressive & More
What "multifocal" actually means, how it differs from progressive, and how Varilux Liberty 3.0, Comfort Max, Physio and XR Series compare.
LENSES
Photochromic vs Polarized Lenses: Which Should You Choose?
Polarized is sunglasses-only at this shop, photochromic can carry a prescription. Real prices from 350,000d, compared in detail at Manh Long Optical.
LENSES
Blue-Light Filtering and UV Protection: What's the Difference
These two are usually sold as one line item, but they block two different wavebands from two different sources. How to tell them apart, and which one you actually need.
LENSES
Anti-Reflective, Anti-Scratch, Hydrophobic: What Each Lens Coating Does
A clear lens today is almost never just glass or plastic. What each coating actually does, and which ones are worth paying for.
LENSES
Varilux Physio Extensee Review: Worth the Upgrade?
Essilor's higher-tier progressive design, built around a wider near-vision zone. Where it actually helps, and where it doesn't.
LENSES
Essilor Lenses: Where Your Money Goes
Varilux, Crizal, Eyezen, Transitions — Essilor splits its lineup by the problem each line solves, not by price tier. What does each one actually do?
LENSES
Essilor Transitions Lenses: How Much Do They Cost?
A pair that's clear indoors and dark outdoors. What Gen S actually changed, and what to ask before buying.
LENSES
What's Better About Essilor Transitions Gen S
Speed, color range, protection, optics, durability — what the 2024 generation actually improved, and what that means on your own face.
LENSES
Photochromic Progressive Lenses: Two Jobs in One Lens
One lens for every distance that also darkens in the sun and clears back indoors. How Essilor Transitions and Zeiss PhotoFusion X compare, and what to check before buying.
LENSES
Zeiss Progressive Lenses: Sharp Vision at Every Distance
One lens for far, intermediate and near vision, with no visible dividing line and no switching glasses. What makes Zeiss progressives different, and which line to pick.
LENSES
Zeiss SmartLife Individual: A Lens Made to Measure for You
SmartLife Individual is Zeiss's most personalized lens line — built around your own face, frame and viewing habits, not an average number.
LENSES
Zeiss UVProtect: Blocking UV Up to 400 nm on a Clear Lens
The 20 nanometer gap most clear lenses leave open, and how Zeiss closes it.
LENSES
Chemi Lenses: Stock or Custom-Ground, A-ONE or A-PLUS
Chemi lenses: stock lenses cut same-day, custom-ground lenses take 10-15 days and cost 2.6 to 6.7 times more. September 2026 prices, 147A Le Duan, 0777 986 999.
LENSES
Tokai Lenses: Index 1.70, 1.76 and the Lutina Lens's 400-420 nm Cut
Tokai lenses in Hanoi: 1.60, Lutina 1.67, 1.70 and 1.76, from 1,200,000 to 9,300,000 VND per pair. Lutina cuts the 400-420 nm band per Tokai's own claim. 0777 986 999.
Lens Coatings
COATINGS
Crizal Easy Pro: What It Adds Over a Basic Coating
Crizal Easy Pro: a real step up from a basic coating, not the top-tier price.
COATINGS
Is Anti-Reflective Coating Worth It? When It Really Matters
Not usually a separate paid add-on. Matters most for night driving, screen use, and video calls.
COATINGS
Crizal Natural Look: 360-Degree Anti-Glare Coating
Crizal Natural Look cuts reflections from every angle, not just head-on. What that means for photos, night driving and everyday wear.
Buying Guides
GUIDE
How to Read a Glasses Prescription: SPH, CYL, AXIS, ADD, PD
How to read a glasses prescription: what OD/OS, Sphere (SPH), Cylinder (CYL), Axis, ADD and PD mean, what plus and minus signs mean, with a worked example.
GUIDE
Contact Lenses or Glasses: Which Should You Choose?
Both correct the same prescription, but comfort, lifestyle and eye health tip the scale differently for each person.
GUIDE
How to Choose Glasses That Actually Fit
How to pick a frame for your face shape, the right lens index for your prescription, and the order to do an eye test in. Full guide from Manh Long Optical.
Eye Health
EYE HEALTH
Astigmatism and Night Glare: Why Lights Look Worse After Dark
Halos and starbursts around headlights and streetlights are a familiar sign of uncorrected astigmatism. Why it happens, and how lenses fix it.
EYE HEALTH
How Nearsighted Do You Need to Be Before You Need Glasses?
There's no single diopter cutoff. What actually decides it is whether blur is affecting your daily life, not a number on a prescription.
Children's Eyewear
CHILDREN
Choosing Glasses for Nearsighted Children
Signs of nearsightedness in children, how often to test their eyes, and choosing a frame that survives a hyperactive kid. Free eye tests for children.
Style & Fit
STYLE
Choosing Frames That Suit Your Face Shape
The old rule still holds: a frame should offset your face, not repeat it. How to read your own face shape before you go try frames on.
Care & Maintenance
CARE
How to Clean and Care for Your Glasses the Right Way
Most scratches and loose hinges come from a few very small daily habits. Here's what to change.
Data & Research
DATA
Myopia and refractive error in Vietnam: what the studies say (2026)
Sourced figures from WHO, IAPB, Ophthalmology, PLoS One and Vietnamese journals, nine studies side by side, and why their numbers disagree. Every figure links to its publisher.
Fun Facts
TRIVIA
Why Do Phone Makers Use Zeiss Lenses?
Zeiss shows up on camera bumps from Nokia to Vivo. What the badge actually means, and what it has in common with the lenses in your glasses.
About Manh Long Optical
ABOUT
Manh Long Optical: 25 Years of Frames, Wholesale and Retail, Lens Partner to Essilor, Zeiss, Nikon
25 years supplying frames wholesale and retail, a partner of Essilor, Zeiss and Nikon lenses — contact lenses, progressives to single-vision, specialty lenses, and modern fitting equipment.
ABOUT
Why Do Many Customers Choose Manh Long Optical?
5 criteria for a trustworthy optical shop: eye testing, product range, price, aftercare, real reviews. How Manh Long Optical measures up, including what it hasn't solved yet.
Have a question these don't answer?
Come in for a free 20 minute eye test, or ask us directly, no obligation to buy.
Manh Long Optical — 147A Le Duan, Cua Nam, Hanoi
Open daily 8:00 – 21:30
0777 986 999 · WhatsApp · Zalo · mlong.optical@gmail.com · Directions