Prism Glasses vs. Reading Glasses: What's the Difference?
They both sit on your nose, but they solve completely different problems. Here's how to tell which one you need (or both).
In this guide
Both are called glasses, and both are used for reading, but they do entirely different jobs. Mixing them up is the most common reason people are surprised when they try lazy glasses for the first time.
The short version
Reading glasses help your eyes focus on close-up text. Prism (lazy) glasses change the direction you're looking. One is about clarity; the other is about posture.
| Reading glasses | Prism (lazy) glasses | |
|---|---|---|
| Main job | Make close-up text clear | Redirect your view about 90° |
| How they work | Curved lenses add focusing power | Right-angle prisms bend the light path |
| Magnify? | Yes, by design | No |
| Best used | Sitting or standing, up close | Lying on your back |
| Corrects your vision? | Yes, to a set strength | No |
| Wear over other glasses? | Not usually | Yes, designed to fit over them |
| Safe to walk in? | Depends on the strength | No; use only while lying still |
What reading glasses do
Reading glasses add a small amount of focusing power so small print looks sharp at a normal reading distance. They're the answer to "I can't see this clearly."
What prism glasses do
Prism glasses solve a different question: "How do I read or watch something without lifting my head?" By bending your line of sight, they let you look forward while lying flat. You can read the full story in do lazy glasses actually work?
Can you use both?
Yes, and if you need reading glasses to see text clearly, you should. Prism glasses don't change your focus, so wear your usual glasses underneath, then the lazy glasses over the top. There's a step-by-step in our guide to wearing lazy glasses over prescription glasses.
Which one should you get?
- Struggling to see small print? Reading glasses (see an eye care professional if you're unsure of your strength).
- Sore neck from reading or watching lying down? Prism glasses may be worth trying.
- Both? Get both. They work together.
Frequently asked questions
Do lazy glasses replace reading glasses?
No. They redirect your view but don't magnify or correct your vision. If you need reading glasses, keep wearing them underneath.
Are lazy glasses the same as prescription prism lenses?
No. Prescription prism corrects eye alignment and is set by an eye doctor. Lazy glasses use periscope-style prisms purely to bend your line of sight.
Can I use lazy glasses with contact lenses?
Yes. They sit on your face just like regular glasses, so contacts don't interfere.
Lie back. Look straight ahead.
Horizontal prism glasses that bend your view by about 90 degrees, so your head can stay right where it's comfortable.
- Read, scroll or watch TV lying flat on your back
- Non-magnifying, fits over your own glasses
- Free shipping and a 30-day guarantee
Keep reading
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