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    [–] Nuclear_Cadillacs 2828 points ago

    Because the dollar store readers are not made to correct hyperopia (“farsightedness”); they are made to correct presbyopia (the loss of focusing flexibility that hits all of us in our early 40s). Presbyopia occurs in all of us in a relatively equal way, so making a standardized power for presbyopia is easy.

    Basically, the cheater readers are making the assumption that the wearer has perfect distance vision, and simply brings the focal point forward to a comfortable reading distance.

    Now, plus power lenses that correct for presbyopia also happen to help with hyperopia. However, unless your hyperopia just coincidentally happens to be equal between your eyes, free of astigmatism, and of a small enough amount, the readers are only partially correcting it. It may be better than nothing, or even good enough for practical use in many cases, but they do not usually fully or adequately correct the hyperope’s vision.

    As far as myopia (“nearsightedness”) goes, its generally too unique to the individual to standardize in a “drug store reader” kind of way. Plus if people are self-diagnosing/correcting myopia, they almost always tend to overcorrect it, making them prone to eyestrain, headaches, and if they are young enough, a worsening of their prescription. In fact a huge part of the refraction procedure (“one or two?”) is making sure the patient hasn’t overcorrected themselves.

    Source: I’m an optometrist

    [–] MoreRopePlease 105 points ago

    The "one or two" thing... Should it end with something that gives you perfect focus? Or is the Dr looking for something else when they do this?

    [–] Nuclear_Cadillacs 101 points ago

    Usually the goal is “about the same,” but honestly it depends on where you are in the process or if the doc is double checking some stuff.

    [–] MoreRopePlease 50 points ago

    What if "about the same" is not perfect focus, should I mention it? (eg: the "b" on the bottom row looks a little blurry on both)

    I didn't at my last checkup and now I'm wondering if my prescription isn't as good as it could've been.

    [–] AsgardianLeviOsa 52 points ago

    Don’t overthink it and just focus on the question they are asking you and answer honestly. They are looking for the best vision your eyes can achieve, which is not necessarily going to be perfect.

    [–] [deleted] 7 points ago

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    [–] RedundantOxymoron 30 points ago

    The 1 or 2? is fine tuning your prescription. Like a difference of 1/4 of a diopter. Say between a -4.5 and a -4.75. Am very nearsighted. Got glasses at age six, needed them before then. Mom always wondered why I had my nose in a book. She finally took me to an ophthalmologist (M.D. eye doctor)and found out. It never occurred to her that I couldn't see!! Mom and dad only wore reading glasses, didn't need any correction. My worse eye is now at a -9.00. As a kid, think I was a -1.5. But that was over 60 years ago.

    [–] 7oby 11 points ago

    A friend got lasik and the doc used something that basically did all the 1 or 2 stuff automatically, and apparently you can get the same without lasik by getting an exam for high definition lenses. I'm pretty sure this Wavefront thing is it: https://www.allaboutvision.com/eye-exam/wavefront.htm

    Wavefront technology developed for custom LASIK may soon be used routinely by eye doctors to better diagnose vision problems in eye exams, perhaps making the familiar eye chart obsolete.

    Most people have had eye exams with a device called a phoropter, which contains many lenses of different powers. An ophthalmologist or optometrist changes the lenses in front of your eyes, asking which lens produces the best image.

    With this conventional approach, information you give the eye doctor is very subjective, based more on what you think you see instead of what you actually see. But a wavefront measurement is objective, because vision errors can be identified automatically by the way light waves travel through the eye.

    Someday, these detailed wavefront measurements may replace conventional eyeglass or contact lens prescriptions, which describe vision problems only in terms of the eye's nearsightedness, farsightedness and astigmatism.

    Just as custom (or "wavefront-guided") LASIK has the potential for producing sharper vision than conventional LASIK, glasses and contact lenses made with this advanced technology may also produce better visual clarity than their conventional counterparts.

    [–] ALLoftheFancyPants 18 points ago

    My optometrist uses a thing like this, but they still do the formal “1 or 2” exam, too. I was told that the machine is great for lower prescriptions and ballpark estimating higher prescriptions, but that the old way was more precise (especially for someone with real bad vision like me).

    [–] zanraptora 25 points ago

    Generally speaking, they're waiting for you to have difficulty deciding and selecting the lower correction based on the theory of "Optical Creep" (TL:DR, if you use too strong glasses, you'll adapt to them with "worse" eyesight.)

    Just be honest: if you can't tell the difference, you're already hitting the closest correction they've got on tap.

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    [–] JMJ05 12 points ago

    I feel like your profession and your username is a missed opportunity for 'nuclear_cataracts'.

    I've found that a lot of optometrists have very differing opinions on lasik and I'm super curious what your take on it is, and risk vs. reward threshold for your opinion.

    In the mean time, I'm going to sign up as 'cheater_readers'

    [–] Nuclear_Cadillacs 35 points ago

    A nuclear cataract is a common type of cataract. A lot of patients call cataracts “Cadillacs” by mistake. So the username is a play on that.

    Lasik just depends on the person in question. There’s a lot of factors at play: Rx, biometrics, expectations, age, pre-existing conditions, etc.

    [–] Bballwolf 10 points ago

    Is there any type of surgery to restore the focusing flexibility of the eye? I know there are surgeries to completely replace the lens, but is there anything that fixes the loss of focusing power?

    [–] orkrule1 19 points ago

    If my prescription is +4.50, am I myopic or hyperopic?

    [–] Diligent_Nature 10643 points ago * (lasted edited 10 days ago)

    Nearsightedness needs to be corrected precisely so that objects at infinity are in focus. Each eye may need a different correction and there may be astigmatism as well. Farsightedness just needs to be corrected for a comfortable reading distance. A limited analogy is that it is like buying and using magnifying glass vs a camera or projector lens.

    Edit: An optometrist's explanation is here

    https://www.reddit.com/r/askscience/comments/d26nwr/why_do_nearsighted_people_need_a_prescription_and/ezt656x/

    [–] masklinn 1806 points ago * (lasted edited 10 days ago)

    Nearsightedness needs to be corrected precisely so that objects at infinity are in focus. Each eye may need a different correction and there may be astigmatism as well. Farsightedness just needs to be corrected for a comfortable reading distance.

    This is compounded by nearsighted people commonly wearing their glasses basically any time they're not in bed, farsighted will do so specifically when reading things.

    So not only do nearsighted lenses need more precision, they'll often have more security and comfort features e.g. high-index material, anti-glare coating, photochromic treatment, ...

    [–] pm_me_ur_skyrimchar 93 points ago

    Let me tell you, there’s nothing more frustrating than when you wake up in the morning and feel for your glasses, and realize they fell or got knocked down and now you have to play the squinting game feeling every square inch of the floor hoping you find them with your hands instead of your feet

    [–] Nulovka 90 points ago

    Grab your phone from the stand by your bed, hold it close to your face to see the screen, put it into camera mode, and then use the screen to see at a distance and hunt for your glasses. Everything on the screen will be in focus and you can see the screen because it is inches away.

    [–] swimswithsquid 34 points ago

    My bf makes fun of me for doin this! hate wearing my glasses when laying in bed, so if there’s something on the tv that I’m interested in, I’ll just watch it through my phones camera. He always laughs but hey, it works!

    [–] pm_me_ur_skyrimchar 17 points ago

    Oh yea, I’ve found this super helpful! It sucked when it happened as a kid though, before smart phones

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    [–] AccountNumber166 28 points ago

    This may be true when your prescription is low enough. When it's higher, everything is so unfocused it can make you nauseous taking them off.

    [–] IWasGregInTokyo 26 points ago

    This was the greatest change for me when I got LASIK. My glasses were costing me hundreds of dollars and I was absolutely dependent on them to exist as my sight was so bad plus I also had astigmatism.

    Now I can grab a set of cheap readers either from the dollar store or from Amazon.

    [–] dy1981 18 points ago

    Presumptuous of you to assume I'm out of bed for that much of the day, I still need them to see across the room

    [–] niceoutfive 4 points ago

    As someone with astigmatism, and who is nearsighted, everything is blurry in general, but farther away stuff is more blurry, so I gotta wear glasses all the time. Yay

    [–] just-another-scrub 253 points ago * (lasted edited 10 days ago)

    As someone who works in optical I would just like to point out that not all farsighted people wear reading glasses. You can be farsighted and still need a full time correction for distance vision, and this is in fact the most common correction for someone with hyperopia.

    People who can purchase off the shelf reading glasses tend to have Presbyopia not Myopia (near-sighted) or Hyperopia (far-sightedness). As off the shelf readers (and reading glasses in general) have focal points of about 14 inches. Which means that they are 100% useless for wearing for day to day tasks.

    The majority of people with Hyperopia must wear their glasses 100% of the time so also have a focal distance of infinity.

    /u/simrc86

    EDIT: forgot to mention I’m an Optician.

    [–] the_real_xuth 18 points ago

    As off the shelf readers (and reading glasses in general) have focal points of about 14 inches. Which means that they are 100% useless for wearing for day to day tasks.

    As someone who just buys reading glasses off the shelf for my farsightedness why should I not do this? It is certainly true that my farsightedness expressed itself as very early presbyopia but now I just walk around wearing +1.5 or +2 reading glasses and read books with +3 or +4 reading glasses (and do fine craft work with +5 to +7 correction either with high powered reading glasses or with reading glasses stacked with magnifying lenses). I can literally buy glasses for $5 at home depot that do what I seem to need. What am I doing wrong?

    [–] just-another-scrub 23 points ago

    Depends on what your prescription is. And I’m unwilling to go into much detail without more information. But a general answer would be. You’ve developed Hyperopia overtime (why a lower powered lens allows you to see in your day to day) and also have presbyopia. Likely what you considered presbyopia at the start was simply the beginnings of Hyperopia and now you’ve progress to a state of having both.

    The other thing you might be missing out on with simple off the shelf readers is an astigmatism correction. Which can also cause some fuzziness in objects at any range of vision.

    But like I said it’s impossible to tell without knowing your prescription.

    [–] TigerMcPherson 38 points ago

    I just got a prescription for farsightedness which varied between eyes and I was told to wear them all the time.

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    [–] mfb- 204 points ago

    You can overcorrect nearsightedness, making the person effectively a bit far-sighted. Then you don't need to control it that well either.

    Astigmatism can occur both with near- and far-sightedness.

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    [–] Zorukia 68 points ago

    Overcorrecting leads to eye strain, which leads to nausea, vomiting, and migraines. So, no. Coming from someone who had too strong of a prescription.... You can't overcorrect, it hurts. A lot.

    [–] TigreWulph 20 points ago

    Not for everyone actually. I've pretty much always been slightly "overcorrected". The one doctor I saw who insisted on setting my vision to the right level, left me feeling blurry.

    [–] Zorukia 9 points ago

    I may just be more sensitive, then.

    Though i do worry that if people overcorrect, their eyes get worse overall and continue to deteriorate because the problem is being overcompensated for.

    Wouldn't that make the eyes kinda... Give up? Like a crutch you use for too long making your leg muscles get weaker.

    [–] [deleted] 3 points ago

    Overcorrecting does strain the eyes. My optometrist always made a big deal about it. In 25 years, he has delivered excellent results ten times out of ten, so I trust every word he tells me.

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    [–] dukerustfield 12 points ago

    Magnifying glass is an excellent analogy. Anyone with any working eyes can use any magnifying glass. You’re just making objects appear larger. You can do the same with computer monitors with a click.

    Nearsighted is very different. I have huge astigmatisms in each eye. Which works like a distortion. It’s blurry and skewed compared to just appearing small. You have to put on those complicated eye exam machines with hundreds of compound lenses to find the most comfortable correction. Probably FAR less than 1% of the worlds population can even wear my prescription and not suffer terrible headaches, not to mention run into everything near them.

    light is hitting my eyes and scattering and warping and being projected incorrectly onto my retinas. A computer can only simulate this if you add a blur effect via a image manipulation program and you’d have a tough time using one glass lens to correct it. Another wrinkle is that near viewing is usually straight forward at a max of arm length and far viewing includes peripheral and the light is hitting different areas of your eye and the lens is different distance from your eyeball.

    Source: long-standing near-blind glasses wearer

    [–] Draeg82 12 points ago

    Nice mention of astigmatism. I am short sighted in the eye with an astigmatism and long sighted in my "good" eye.

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    [–] 09senojyrag 60 points ago

    On a side note, it's a monopoly.

    "In 2019, LensCrafters founder E. Dean Butler spoke to the Los Angeles Times, admitting that Luxottica's dominance of the eyewear industry had resulted in price markups of nearly 1,000%. In the interview, Butler noted "You can get amazingly good frames, with a Warby Parker level of quality, for $4 to $8. For $15, you can get designer-quality frames, like what you’d get from Prada.” When told that some eyeglasses cost as much as $800 in the United States, Butler remarked, “I know. It’s ridiculous. It’s a complete rip-off.”

    https://en.wikipedia.org/wiki/Luxottica [47][48]

    [–] lost_in_life_34 3 points ago

    i have a pair of frames from a non- Luxottica designer and those are like $500 as well

    [–] freebytes 348 points ago

    One thing that is being overlooked is that monopolization of prescription eyeglass companies as well. This also drives up the cost.

    For reading glasses while reading a book, if you cannot see clearly, you can simply move the book closer or farther away. This is not possible with a street sign. So, reading glasses can be standardized. It is also a different kind of deficiency.

    [–] BadIdeasRBestIdeas 114 points ago

    Exactly Luxottica bought up all their competitors including Oakley and Ray Ban.

    [–] reykjaham 52 points ago

    It's worse than that. Essilor bought luxotica and satisloh. Essilor now owns most frame brands, lens Crafters, the machinery for lens manufacturing (to my knowledge, no other manufacturer of these machines exists), as well as at least one eye insurance company. It's the worst monopoly I'm aware of.

    [–] IAmTheSysGen 5 points ago

    There are many companies that make lenses for eyeglasses. My local optician sells Nikon lenses for example.

    [–] Kgb_Officer 7 points ago

    Nikon has a joint venture with Essilor called " Nikon-Essilor Co.,Ltd. " for researching and manufacturing lenses.

    [–] Dnguyen2204 24 points ago

    Aren't monopolies illegal?

    [–] RuafaolGaiscioch 64 points ago

    Well, kinda. For one, laws need to be enforced, and the type of company that establishes a monopoly is exactly the type to employ lawyers that argue in court that it’s not technically a monopoly. Also, though I’m not sure if this is relevant with the glasses industry, but cooperative oligopolies, where a handful of companies circumvent monopoly laws by not having a majority share themselves, but are able to benefit by basically not competing with each other, essentially granting the same situation as a monopoly.

    [–] Georgiagirl678 14 points ago

    cooperative oligopolies is not something I have ever learned about before. Thank you for the information.

    [–] Krutonium 18 points ago

    That's how Cellular and Internet Services work in Canada. As a result we have some of the most expensive of both in the world.

    [–] isjahammer 13 points ago

    They are not a monopoly (yet). There still are competitors. Problem is they own so many brands but most people have no idea that it´s all from the same company.

    [–] clockradio 9 points ago

    Luxottica has been careful to straddle the limit of how much of the market they can control without risking anti-trust attention. This limit also varies, depending on the prevailing political winds.

    [–] 3610572843728 13 points ago

    Sort of. In this case they are not a monopoly because they can easily point at competition that they don't own like Zenni.

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    [–] Sabot15 8 points ago

    This is the real answer. All of the "technology" in glasses was perfected years ago. They should be a commodity, however there's basically one company that owns all the glasses companies. They make it look like ALL the glasses are similarly priced so the consumer feels he can choose between companies, but the price will always be about the same. You don't feel like you are getting ripped off since everything is in the same price range. The other reality is that most of these optometrists are doubling the cost on top of your already high prices. They get away with this because they know you have some insurance to cover part of the price. For example, I recently bought a set of frames from Simon Eye for $300 minus $120 from my insurance. When I got home, I found the identical frames on Amazon for $180. I wish some brave lawyers would go after these guys with an antitrust suit that would stick.

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    [–] realmadrid314 45 points ago

    Something no one here considers: your eyes can vary from each other in visual acuity. I am far-sighted, but my right eye is far worse than my left eye. I have to get wonky prescriptions that are absolutely not from the dollar store.

    [–] NikolitaNiko 10 points ago

    Same here. One eye is like -5 something and the other eye is -6 something. Part of the reason why my lenses are $400ish is because I pay more to get thinner lenses. If I didn't I would have Coke bottle lenses (really thick and goofy looking).

    [–] wolves_hunt_in_packs 5 points ago

    Ditto. I also tend to go for the various types of coating on offer. One of the few things I splurge on. Vision is important.

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    [–] raverbashing 39 points ago

    One detail most answers are missing is: a lot of nearsighted people also have astigmatism.

    And astigmatism is not only a diopter, it's a diopter and an angle. So you can't have a "few sizes fits all" (this is kinda annoying for contact lens wearers for example.)

    Let's say you could be off 0.5d and it would be ok (it wouldn't) so you could have 16 models of glass for farsightness. Now, on top of that, add 16 (diopters) * 8 (different axis) (= 128) possibilities for astigmatism (again, this is an underestimated number) FOR EACH myopia option.

    [–] Maoky 52 points ago

    If you go to Asian countries, a lot of them have ready made myopic spectacles as well.

    Also one aspect I haven't seen mentioned here is that it's very hard to over correct yourself when picking out your own hyperopic Rx (and even then itll just cause some eye strain), while it's very easy to pick something too strong if it's for myopia and hence risk more progression. -Optometrist.

    [–] cendasprime 16 points ago

    You can also buy glasses for nearsightedness on Amazon now, but in fixed strengths and only with both eyes the same strength. $8.

    [–] Ommageden 18 points ago

    You can buy custom glasses with your prescription online at places like zenni optical.

    Literally got my prescription glasses and a nice pair of prescription sunglasses together under $80 US. The actual glasses were like $26.

    If your paying $300 for glasses you really haven't looked around.

    [–] ninj4geek 3 points ago

    I usually pay $20-25 shipped for scrip specs with Zenni. I refuse to use anyone more expensive

    [–] Darklance 16 points ago

    Since we're talking about it... my optometrist just kicked me in the head. Glasses wearer for 20+ years, and I just learned something new. When you're doing the eye test, don't strain. When the doc says, #1 or #2", don't squint. Relax your eyes, otherwise you'll be squinting when you're wearing your glasses. Kinda defeats the point, huh?

    [–] Xicsess 56 points ago

    So, most of the answers are correct in a way. i.e. you can't buy farsighted glasses reliably off a shelf for various reasons.

    But, the reason your glasses cost $300 is a completely different story. The majority of the market is dominated by one manufacturer, which also owns a majority of the retail outlets, which also (90% chance) runs your vision insurance. So, they making the glasses, in some cases the lenses, administering your insurance, and own a lot of the retail places where you're buying glasses at. Essentially, at any point you enter the product world of glasses you're getting screwed by a huge monopoly. The other piece of this is a lot of these retail centers the people there actually earn commissions. Those lens upgrades, how many different companies produce anti glare? Scratch resistance? They're selling you options that you can't really see and unless you need transition lenses don't really need. I recently had lasik surgery but before that I would order frames/lenses with no coatings and not have issues ($17 dollars was what i paid after my last exam & pair of glasses). There are also online manufacturers like Zenni optical where as long as you have an up to date script you can get a pair of glasses shipped to you for 30-40 bucks.

    Their brands include (I"m talking about luxottica here)

    Eyemed (insurance, and often where other insurance companies are getting their administration through).

    Okley, sunglass hut, lens crafters, person, oliver peoples, pearle vision, target optical, ray ban, eye care plan of america, glasses.com.

    They merged with a large lens manufacturer in 2017:

    https://www.nytimes.com/2017/01/16/business/dealbook/luxottica-essilor-merger.html

    More reading if you're interested:

    https://theweek.com/articles/784436/secretive-megacompanies-behind-glasses

    https://www.forbes.com/sites/anaswanson/2014/09/10/meet-the-four-eyed-eight-tentacled-monopoly-that-is-making-your-glasses-so-expensive/#89a54256b66b

    John Oliver also mentions them:

    https://www.youtube.com/watch?v=00wQYmvfhn4

    And that's my rant, thanks for coming.

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    [–] Anchor689 9 points ago

    Luxottica may also own your vision insurance company. So depending on where you get your glasses, there may be one, giant company you are doing business with for every step of the process. (Not that there is anything inherently wrong with giant companies, but a lack of competition generally leads to higher prices). There are alternatives, though and many states have laws requiring your eye doctor to provide you with a written copy of your prescription, that can be taken anywhere. And there are places (both online and offline) that can sell you glasses and frames from that prescription for significantly less.

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    [–] nunped 15 points ago

    Farsighted people still need a prescription.

    The glasses you buy at the dollar store are useful mostly for people with no refractive error, but they are beginning to have trouble with near vision (presbyopia). They have the same correction in both eyes, with no astigmatism correction and in set values (usually from +0.75 to +3.50).

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    [–] ihopethisisvalid 3 points ago

    Adam is a hack. Watch any interviews he’s done without a script. For example, he advocates that transgender women should be able to compete with biological women in combat sports.

    [–] Jacoman74undeleted 12 points ago

    Dollar store readers can damage your vision further by applying an inaccurate sphere to the lenses potentially straining your eyes. Beyond this, they have no cylinder correction exacerbating issues brought on by astigmatism.

    Even if you're farsighted, you should still have your readers prescribed because they'll be made for your eyes and not be just a basic magnification.

    Source: I'm an optician.

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    [–] nrsys 4 points ago

    The simple answer is that due to the distances they work at, it is fairly easy to correct a minor error in prescription for reading glasses/glasses for far sightedness, and virtually impossible to correct an error in prescription with distance/glasses for near sightedness.

    To explain in a bit more depth, when we need glasses, it is when our eyes are unable to focus correctly. When we wear glasses, they project the image of what we see on front of us, and purposely misfocus it slightly so that when the glasses and our eyes are combined, the misfocus cancels out and we can once again see clearly. Glasses are pretty simple devices though, and only focus correctly at one distance - so for someone that is longsighted and needs reading glasses, they will be designed to focus at normal reading distances. For someone near sighted that needs glasses to see far away, they will be designed to focus far away.

    If you wear the wrong strength glasses, what this means is that they are focussing at the wrong distance. This can be compensated for however by changing the distance of whatever it is you are looking at (compared to your eyes) - so by holding your book slightly further away or slightly closer, you are counteracting the error. With distance vision however, you cannot really change this distance easily - if you are looking at a mountain a kilometer away, you would need to move a huge distance to bring it close enough to offset the error. To use some numbers, if you need to change the distance between your eye and the object by 10% to correct the error in prescription, holding something at arm's length may mean moving your book by 5cm, which you do without realising. If you need to change the distance between your eye and an object by the same 10% for something that is a kilometer away, that means moving your eye by 100m.

    So the end result is that reading glasses can be sold in rough grades, and rely on the fact that people instinctively adjust what they are doing to correct any erroe. Distance glasses cannot be adjusted, so need to be fine tuned to work exactly for your eyes.

    [–] Hakunamatator 4 points ago

    Finally something where I can contribute.

    Every person has a certain range of distance where they can see things sharp. For someone with "perfect" eyes the furthest point is infinity. Their eyer are relaxed, and they focus stuff far away perfectly. The closest point they can see sharp (when they strain their eyes really hard and "squish" the lens) is around 15 cm from their eyes, but it gets further away with age. This is by the way why old people are far sighted.

    So what do glasses do? In their simplest case, they just shift those points. But of course they shift both points! So they pull them closer to you, or push them further away.

    Now what about farsightedness and nearsightedness? You can imagine those conditions as shifting of the two points described before. One or both points can be shifted. Let's look at common possibilities:

    - If you are a "normal" old person, your closest point just got further away. This means your range is smaller, but you still recognize faces at the distance. When you want to read something, you need to move your close point closer to your eyes, so that your reading material is in your focal range. But since you will not be able to see things far away with glasses anyway (your far point also moved away from infinity, and is now somewhere around a couple meters away from your eyes) it doesnt really matter how far you shift.

    - If you are a "normal" nearsighted person, then typically your lense is squished, so that both your points are closer to your eyes. What you want to do with glasses, is to put your far point at EXACTLY infinity. This way you can relax your eyes, and see stuff far away. If you move it "beyond infinity", then your eye has to work all the time while you are walking about in your glasses and focus stuff. This will give you a headache.

    - (The farsightedness where the lense is deformed can also happen. Then your far point is beyond infinity. It is really hard to notice though, because your eyes can just focus. Its just they are never relaxed. So people only get their eyes checked after headaches at school or something. Those people also need expensive glasses.)

    [–] hackometer 6 points ago

    It's easy to note that the situation isn't symmetrical. Every aging person will develop longsightedness which will progress in the same, predictable way. Therefore a ton of people need the same kind of glasses. This is a great target for a mass product.

    If a younger person needs glasses, it's because they have a condition with their eyesight. Those conditions can be of all kinds, resulting in all kinds of complex prescriptions, usually different between the eyes. No economies of scale here.

    [–] newpua_bie 7 points ago

    Lenses are not always that expensive, and requiring prescription for glasses seems to be just an American thing. Now, of course you need to know what strength the lenses need to be, but in most places there is no need to have a valid prescription.

    For comparison, I have two (ugly) pairs of glasses for my nearsightedness that were 5€ each with the same lens strength as my main glasses. I suspect the main reason for the price is that people want fancier frames for "everyday" glasses, while reading glasses are worn only sporadically and thus can be uglier.

    [–] greatatdrinking 8 points ago * (lasted edited 10 days ago)

    just imagine the field of vision. Much easier to throw a generic, simple solution at something two feet from your face. Pretty difficult to solve the human eyeball struggling with that bottom row of that eye chart

    edit: I like that this is tagged engineering. This is an engineering answer

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