Originally published at: How thick are your prescription glasses? | Boing Boing
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Mine would probably be close to that thick if I didn’t get the high index lenses. I can see clearly a full 6” in front of my face without them.
…and with them, I can’t see clearly less than a 1.5 feet in front of my face. The perks of getting older. I do have reading glasses, but can’t quite bring myself to do bifocals yet.
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Mine would come close to that if I choose the cheapest lens material for them. I go with (more expensive) ultralight stuff to avoid that, as well as keep them from slipping down my nose as much.
EDIT: my first pairs of glasses in grade school were called “coke bottle bottoms” for a reason.
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Deeper dive into Reddit comments touches on Therapeutic Tint lenses for treating migraines and all sorts of other ailments.
Found this interesting breakdown on what sort of lens tint applications there are:
Last column includes citations to lots of legit sources (I’m a vision scientist) that one could easily burn an afternoon skimming. …if you’re into that sort of thing.
(Correction: updated link to original source— w/working citation links)
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Love that tag “BET THOSE EYELASHES TOUCH” lol
Yup.
Edit: No longer, though. Had cataract surgery, just need drugstore reading glasses now.
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Medical Science, like all of the Sciences, is so cool! My Dad got plastic lenses for his eyes and was really happy with the results.
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“It’s just that…when…whatever happened happened, it’s like my senses have been dialed to 11. There’s way too much input so they just kinda help me focus.”
- Spider-Man
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Progressive lenses are your friend, especially when in the car and on the computer. I can read a book/phone in front of my face out to 8" maybe (nearsighted), but then my progressives easily take me from lap/monitor distance out to eternity. 
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I wear regular sunglasses over my contacts and it’s perfect. I wear readers over my contacts, too. I even have separate cellphone/book readers and separate computer readers.
@DiveGirl, I can’t handle progressive. I felt like I had to constantly adjust the tilt of my head just to get the most optimal position. Too frustrating. My husband? He wears progressives and loves them. The idea of putting something on his eyeballs freaks him out.
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My (naïve both with respect to the last time I touched optics in the context of physics class and to the zero times I’ve touched optics in the context of optometry) impression is surprise here; just because of the fact that there’s simply not so much lens volume in the eye itself compared to the volume of that corrective lens, so I’m surprised that the natural lens could(without being grossly abnormal, tumor impinging on the eye socket and deforming the eyeball or something like that) could have so much need of adjustment in such a small space when the corrective lens requires so much space to implement the adjustment.
Does anyone know how the problem breaks down? Are materials that are both durable and cost effective not actually all that hot optically, so you need to brute force it a bit unless you are willing to spend $10,000 on yttrium doped exotic glass and metamaterials that die if you look at them funny? Am I starkly underestimating the amount of lens the eyeball manages to implement? Are the edges of corrective lenses particularly thick, even if the active areas aren’t, just because it’s cheaper to stock blanks in fewer sizes and only grind the areas that matter rather than thinning across the entire lens?
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I never want my eyeglasses to be that thick again. Decades ago I switched away from glasses to contact lenses because thinner lenses were either not possible or not affordable.
In more recent years I’ve switched back so my corrective lenses can serve all purposes (distance, reading, and sunglasses - with photo-gray lenses). There is also an extraordinary dispensary nearby with frames that use small lenses and fit an adult’s head.
Now my thickest lens edge is just under 4.5 mm (with a -9.75/-9.5 prescription). That’s around .175 inches.
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The large area of sunglasses forces the lenses to be farther from the front of the wearer’s eyes. Smaller lenses can be placed closer and won’t require as much thickness for the same material.
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I’d be curious to know if anyone has been futzing with ‘active’ progressive lenses and, if so, how close to viability they are.
You can make a lens adjustable by using tricks like encapsulating an optically acceptable fluid between the front and rear layers of the lens and adjusting the pressure to adjust the shape(there was a cool proposal to use this to make eyeglasses available in poor regions without optometrists by having liquid-filled lenses that could be user-tuned while being worn).
You can also get fairly compact laser or ultrasonic rangefinders(potentially both to cover overlaps in which one works best at various distances); so, at least in principle, it seems like you could have a set of glasses that adjusts itself to the distance of the object being corrected for across the entire lens.
This would obviously sacrifice passivity; and I’d imagine that it’d be nausea hell if the ranging and adjustment process wasn’t really, really, finely tuned; but it would avoid some of the cruder heuristics of just grinding different parts of the lens differently and assuming that the user will do different things at different angles.
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Ah, that does make sense. Also clears up why nobody wears 10mm thick contact lenses. Thanks.
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I have very bad astigmatism, so my old glasses growing up where super thick in the lower right and left quadrant. Over a half inch, easy. If i got hit in the face with a ball it would cut my cheek.
Thanks to newer technology, and smaller sized lenses, they are still thick in the grand scheme of things, but looks like a little under half an inch. I don’t have a ruler near me.
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Those are some chonkers.
Mine top out at ~7mm, and are the absolute thinnest/lightest I can get. At -13, I can see clearly about 2-3 inches in front of my face…and does that really count?
From a few years back –
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The weight of those lenses on my nose would GIVE me a migraine!
I say that as another long-term member of the “Coke bottle bottom” glasses club.
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That happened at first with my husband’s lenses. Once the lenses were adjusted, he was overjoyed with the results. But he’s worn glasses since he was four.
The issue for me is that I’m a bit of a wiggly worm. I don’t want to keep my head just so to see what I need to see clearly. I’ve been wearing contacts since I was 16, so I’m used to not wearing glasses. Using readers has been fine for me, although I do pack sunglasses, regular glasses (I remove my contacts at night), and readers whenever I travel. My purse is basically used for my 3½"x2½"x½" wallet and my three sets of glasses. That’s it.
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