How to Read Your Glasses Prescription (OD, OS, SPH, CYL)
The short answer: Your prescription lists each eye on its own line. OD is your right eye, OS is your left. SPH is the main power, minus for nears...
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How to Read Your Glasses Prescription (OD, OS, SPH, CYL) -
Progressive vs Bifocal Lenses: Which Do You Need?Progressive vs Bifocal Lenses: Which Do You Need?
The short answer: Bifocals split one lens into two zones, distance on top and reading below, with a visible line between them. Progressives blend... -
What Are High-Index Lenses?What Are High-Index Lenses?
The short answer: High-index lenses use a denser material that bends light more, so a strong prescription is ground thinner and lighter than stan... -
Photochromic Lenses Explained: How Transition Lenses WorkPhotochromic Lenses Explained: How Transition Lenses Work
The short answer: Photochromic lenses, often called transition lenses, hold a dye that darkens when ultraviolet light hits it and clears when the... -
What Are Spring Hinges on Glasses?What Are Spring Hinges on Glasses?
The short answer: A spring hinge holds a small internal spring that lets the temple flex outward past its normal open position. The arm gives und... -
Do Sunglasses Expire? When to Replace Your LensesDo Sunglasses Expire? When to Replace Your Lenses
The short answer: Sunglasses carry no printed expiry date, but their UV protection can fade. Sunlight slowly breaks down the lens coating over ro... -
Cat-Eye Sunglasses: Who Do They Suit?Cat-Eye Sunglasses: Who Do They Suit?
The short answer: Cat-eye frames lift at the outer corners, which pulls the eye upward and adds width across the top of the face. They flatter ro... -
Wayfarer vs Clubmaster: What's the Difference?Wayfarer vs Clubmaster: What's the Difference?
The short answer: The wayfarer is a full acetate frame with a bold trapezoid front and thick rims all the way around. The clubmaster is a browlin... -
What Is Anti-Reflective Coating, and Is It Worth It?What Is Anti-Reflective Coating, and Is It Worth It?
The short answer: Anti-reflective coating is a thin, multi-layer film bonded to your lenses that cancels reflections. It clears the ghost glare f... -
Metal vs Titanium Glasses Frames: Which Is Better?Metal vs Titanium Glasses Frames: Which Is Better?
The short answer: Titanium is a metal, so the real comparison is titanium against common frame metals like stainless steel and monel. Titanium we... -
Polarized vs Non-Polarized Sunglasses: Which Do You Need?Polarized vs Non-Polarized Sunglasses: Which Do You Need?
The short answer: Polarized lenses add a filter that blocks the horizontal glare bouncing off water, wet roads, snow, and car hoods. Non-polarize... -
Do Blue Light Glasses Actually Work? An Honest AnswerDo Blue Light Glasses Actually Work? An Honest Answer
The short answer: Mostly no, not the way the ads promise. The American Academy of Ophthalmology says there is no evidence that blue light from sc...
