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  #1  
Old 08-02-2009, 10:16 PM
Tripler Tripler is offline
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So, why does one need a prescription for distance glasses, but not reading ones?

Disclaimer: I looked. I looked here on the boards, and on the SD main page. To my knowledge, the question has not been asked.

I was walking through a store today, and noticed they always seem to have reading glasses on the endcap. They even have a little mirror so you can see yourself and how you look in the $2.99 pair.

So, why does one need a prescription for distance glasses (nearsightedness), but one apparently doesn't for reading glasses here in the U.S.?

I mean, is nearsightedness that different from farsightedness and vice versa? Isn't one just as bad as the other? I don't quite understand how one can self-diagnose in one but not the other. . .

Tripler
I'm forced to wear contacts.
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  #2  
Old 08-02-2009, 10:45 PM
Broomstick Broomstick is offline
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You can get off the shelf reading glasses only up to a certain strength. If you need more than that, you need a prescription.
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  #3  
Old 08-02-2009, 10:57 PM
panache45 panache45 is offline
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The glasses you're referring to are nothing more than magnifiers, and the same for both eyes. Real prescription reading glasses correct for more than generic farsightedness, e.g. astigmatism.
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  #4  
Old 08-02-2009, 11:03 PM
Otara Otara is offline
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Reading glasses are generally for age related nearsightedness or presbyopia. This is often pretty easily correctable and most importantly pretty much everyone gets it sooner or later so the potential market is very large. Also they can be fairly 'quick and dirty' as long as the required text is readable.

Other kinds of eyesight issues are less common, more likely to need a more complicated lens solution, and a more precise adjustment is generally wanted.

Otara
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  #5  
Old 08-02-2009, 11:20 PM
Ferret Herder Ferret Herder is offline
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Plus distance glasses are typically worn for longer periods of time than reading glasses, and the wrong prescription can cause eyestrain and even headaches. Distance vision glasses are very easy to "overcorrect" - people like looking through stronger and stronger lenses in search of "perfectly" sharp vision, but can find that they have a too-strong pair that really strains the eyes.
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  #6  
Old 08-03-2009, 11:37 AM
Nametag Nametag is offline
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You can try on a pair of +0.5 readers and actually get the same prescription that an optometrist would prescribe for you -- if you have otherwise good vision, presbyopia is predictable and uncomplicated. Most importantly, it's unequivocal; if it's blurry, you know goddamn well it's blurry, and if it's blurry, you can shift the glasses or the text until it's in focus.

Errors in distance vision, like my myopia, are often complicated: there's more than a diopter's difference between my eyes; I also have astigmatism, which doesn't bother me when reading, but can be incredibly frustrating at distance. And they're not easily perceived: small errors in the prescription can cause large deficits in vision, but people will walk around with it anyway; worse, they'll drive with it. Worse, they'll pay for crappy glasses that cause headaches and then refuse to wear them, or make some other decision that leads to functioning practically blind, because unless you have a standard for comparison, you simply don't know how well you could be seeing.
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  #7  
Old 08-03-2009, 11:49 AM
magellan01 magellan01 is offline
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In addition to what others have said, sometimes, they eyes need different strengths. I started needing glasses just for reading. At first, reading glasses (simple magnifiers) were fine. But then I had an eye exam and discovered that I needed different strengths for each eye. Another thing is that while those cheap glasses at a drugstore will help you read, the won't help you make a good impression in a meeting. One of the best things I did was get a great pair of beautiful glasses for meetings. As they say, you only get one chance to make a good first impression.

A good place to get nice glassesódesigner ones for meetings as well as cheaper ones for around the house is readingglasses.com. Great selection, great prices, and a really intuitive, easy-to-use site.
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  #8  
Old 08-03-2009, 11:54 AM
Reno Nevada Reno Nevada is offline
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Also, you don't need a prescription for eyeglasses in the same way as you need a prescription for, say, Codeine. If you walk into an eyeglass-store and order a pair of glasses with such and so curvature in the left lens and thus and so in the right, they will go ahead and make them up. The prescription is just a communication from someone who measured your vision to someone who will make a corrective lens for that vision. It's just that (for most people) you need to special order the glasses.
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  #9  
Old 08-03-2009, 01:41 PM
BubbaDog BubbaDog is offline
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Quote:
Originally Posted by Reno Nevada View Post
Also, you don't need a prescription for eyeglasses in the same way as you need a prescription for, say, Codeine. If you walk into an eyeglass-store and order a pair of glasses with such and so curvature in the left lens and thus and so in the right, they will go ahead and make them up. The prescription is just a communication from someone who measured your vision to someone who will make a corrective lens for that vision. It's just that (for most people) you need to special order the glasses.
I agree with you but one time I went to get a pair of glasses for driving and I ran into a problem. I had recently had Lasik surgery and the doctor "missed" on one eye and instead of perfect distance vision I had one eye which had a vision quality that was weak at distance and passable at reading. The Lasik optometrist offered to correct my out-of-range eye but we both agreed that it was a comfortable range for me since it gave me the ability to functionally read (I had reading glasses for long periods of reading).

The doctor wrote a prescription to improve the distance eyesight in for my out-of-range eye. What I didn't know is that he "softened" the vision in the other eye on the prescription.

So when I took the prescrip to the Walmart vision center and got my glasses the "bad" eye could see great but the "good" eye lost its sharpness.

I complained to the technician who told me that the good-eye side of the glasses was dumbed down. I told him that it sucked and that all I needed in the good side was transparent glass.

He said that he couldn't change the lenses without a doctors prescrip.

I said that its not a prescrip its clear glass.

He didn't budge.

I ended up just popping out the good-eye lens and looking like a dork with my one lens glasses on.

Since I only use them for long distance driving it doesn't make much difference.

Still, I was just a little teed off that I couldn't have a non prescription lens put into my glasses.
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  #10  
Old 08-03-2009, 02:34 PM
Sailboat Sailboat is offline
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Also, improper reading glasses are used in a chair and may give you a headache. Improper distance glasses are sometimes used in an SUV and may result in a driver running over a playground full of apple-cheeked children being raised by singing nuns. The consequences are more serious.
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  #11  
Old 08-03-2009, 03:00 PM
glowacks glowacks is offline
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Quote:
Originally Posted by BubbaDog View Post
I agree with you but one time I went to get a pair of glasses for driving and I ran into a problem. I had recently had Lasik surgery and the doctor "missed" on one eye and instead of perfect distance vision I had one eye which had a vision quality that was weak at distance and passable at reading. The Lasik optometrist offered to correct my out-of-range eye but we both agreed that it was a comfortable range for me since it gave me the ability to functionally read (I had reading glasses for long periods of reading).

The doctor wrote a prescription to improve the distance eyesight in for my out-of-range eye. What I didn't know is that he "softened" the vision in the other eye on the prescription.

So when I took the prescrip to the Walmart vision center and got my glasses the "bad" eye could see great but the "good" eye lost its sharpness.

I complained to the technician who told me that the good-eye side of the glasses was dumbed down. I told him that it sucked and that all I needed in the good side was transparent glass.

He said that he couldn't change the lenses without a doctors prescrip.

I said that its not a prescrip its clear glass.

He didn't budge.

I ended up just popping out the good-eye lens and looking like a dork with my one lens glasses on.

Since I only use them for long distance driving it doesn't make much difference.

Still, I was just a little teed off that I couldn't have a non prescription lens put into my glasses.
I presume the doctor write a prescription for both eyes. If so, the technician is probably bound by a policy to only give customers exactly what their prescription indicates. They probably don't want some schmoe second guessing the results of their eye exam; there might be legal repercussions if they knowingly give someone corrective lenses that don't match a professional's opinion of that person's eyesight defects.

You can't exactly just walk into a eyeglass shop and say you are having trouble seeing in the distance and have them custom grind lenses based on your non-expert opinion of what's needed. There are a lot of factors involved in determining the right corrective lens for you, ones that you can't possibly be fully aware of without an eye exam.

On the other hand, people with otherwise perfect eyesight will, with age, slowly become less able to focus their eyes at a close distance and need don't need an eye exam - just a magnifier.
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  #12  
Old 08-03-2009, 03:06 PM
constanze constanze is offline
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IAMNAEyedoctor, but you should get a prescription for all kinds of glasses, to make sure about astigmatism or differences in your eyes (a .25 difference between left and right eye is easy to miss but not good long term). Just as you should have your eyes checked regularly anyway.

I think that besides the factors that have been mentioned already - that reading glasses are worn short time only, less complicated to correct for - it's the bigger size. Almost everybody will get short-sighted in old age and need reading glasses at one point or other (unless they have pre-existing conditions, where you reach a magical point where both faults cancel each other out, and then enter that complicated area of needing double-lens glasses for distance and reading; or if people already have glaucoma/cataract and got operated for that).

So a lot of people need reading glasses, and many need them quickly. If you left your reading glasses at home, or broke them, and a new pair of generic, non-fitted glasses at the supermarket is only 5 or 10 Euros, then you might be more inclined to buy a new pair then if you have to make an appointment with the eye doctor to get a prescription, go to the optician, wait until the glasses come back from being made (7 to 14 days) and cost 20 Euros up.

With fitted glasses for distance and other problems, you have not a lot of choice: if you break them, you go to the optican and get them replaced, and hopefully have an old pair laying around you can use in the meantime.
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  #13  
Old 08-03-2009, 05:39 PM
lissener lissener is offline
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The point of an eyeglass prescription is not to protect the consumer from taking too much of the wrong kind of drug, like a drug prescription. It's because a laymen isn't very likely to be able to diagnose his own eye problems PLUS design the lenses needed to correct it.

Reading glasses are just generic magnifiers.
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  #14  
Old 08-03-2009, 05:46 PM
Malacandra Malacandra is offline
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Another useful application for store-bought readers is if you already have contacts that bring your eyes up to par. I'm much shorter sighted in my left eye than my right, but the contacts fix that, and readers then help my middle-aged eyes to do close-up work. (While I'm moderately astigmatic, each eye is crooked in a different plane, and the brain does a reasonable job of building a composite picture from both eyes.)
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  #15  
Old 08-04-2009, 11:43 PM
Tripler Tripler is offline
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Quote:
Originally Posted by panache45 View Post
The glasses you're referring to are nothing more than magnifiers, and the same for both eyes. Real prescription reading glasses correct for more than generic farsightedness, e.g. astigmatism.
Oh jeez, and here I thought it kind of brought things into focus--like things were blurry. So, they're just magnifying glasses, not corrective lenses then?

Quote:
Originally Posted by Sailboat View Post
Also, improper reading glasses are used in a chair and may give you a headache. Improper distance glasses are sometimes used in an SUV and may result in a driver running over a playground full of apple-cheeked children being raised by singing nuns. The consequences are more serious.
Duly noted. I kind of figured there was a scale in activity immediately after I posted--using just the sort of scenario you mentioned.

After reading through the thread though, I guess it's kind of like an over-the-counter quick fix for eyesight versus a long-term medicine. Which, makes sense to me.

Tripler
Still wearing contacts.
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  #16  
Old 08-04-2009, 11:52 PM
Fear Itself Fear Itself is offline
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Originally Posted by Reno Nevada View Post
If you walk into an eyeglass-store and order a pair of glasses with such and so curvature in the left lens and thus and so in the right, they will go ahead and make them up.
That has not been my experience. I wanted a new pair of glasses made up with my old prescription, and they refused because it was more than two years old. Now, this may have been because they also offered eye exams which they wanted to sell me, but that would apply if I just handed them my own hand written lens specs.
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  #17  
Old 08-05-2009, 12:39 AM
Kevbo Kevbo is offline
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Quote:
Originally Posted by Tripler View Post
Oh jeez, and here I thought it kind of brought things into focus--like things were blurry. So, they're just magnifying glasses, not corrective lenses then?
They allow people with normal (or corrected|) distance vision to focus at short distances. So at close distance, they ARE corrective. They also magnify, which helps, but this is just a happy side effect. If they didn't, they would still be helpful.

When you see an old fart holding something at arms length to read it, that is someone who needs readers.
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  #18  
Old 08-05-2009, 10:38 AM
cromulent cromulent is offline
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Actually, if you're a hyperope (farsighted), plus lenses are corrective lenses for you, even at a distance. They may not be perfect (or even close) if you a) have astigmatism b) have a different prescription in each eye or c) have an interpupillary distance that's different from the average. But in theory, the plus lenses could be used for distance correction for a farsighted person requiring simple, equal, non-astigmatic correction.
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  #19  
Old 08-05-2009, 10:58 AM
chaoticbear chaoticbear is offline
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Quote:
Originally Posted by Reno Nevada View Post
Also, you don't need a prescription for eyeglasses in the same way as you need a prescription for, say, Codeine. If you walk into an eyeglass-store and order a pair of glasses with such and so curvature in the left lens and thus and so in the right, they will go ahead and make them up. The prescription is just a communication from someone who measured your vision to someone who will make a corrective lens for that vision. It's just that (for most people) you need to special order the glasses.
Also chiming in to say that this isn't the case. Eyeglasses need a prescription just like anything else.
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  #20  
Old 08-14-2009, 08:08 AM
Anaglyph Anaglyph is offline
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With reading glasses, you can make fine adjustments by altering the distance to whatever you are reading, therefore the correction does not have to be as precise.
For long distance viewing (correction of shortsightedness), this is not an option.
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