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  #1  
Old 04-17-2011, 11:54 AM
samclem samclem is online now
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Are cheap generic reading glasses OK to wear while Driving?

Don't know if this is clear.

The $1.99 kind of glasses sold in discount stores for reading. These are over-the-counter magnifying glasses. What are the downsides of wearing these while driving?
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  #2  
Old 04-17-2011, 11:59 AM
Pai325 Pai325 is offline
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Why do you need reading glasses to drive? I'm just curious. I'm nearsighted and need my glasses so I can see the road, but I thought reading glasses were for close work, so I thought they might impede your far vision, if that makes sense.
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  #3  
Old 04-17-2011, 12:00 PM
running coach running coach is offline
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Not being able to see past the hood?
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  #4  
Old 04-17-2011, 12:06 PM
johnpost johnpost is offline
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reading glasses focus at one foot away. computer glasses at about two feet.

wearing either and trying to view things farther away will be not as clear. you won't be able to read signs far away as quickly.

bifocals with upper distance (or no correction) and lower for two feet will allow you to read the dash display. if no distance correction half glasses for two feet might also work.
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  #5  
Old 04-17-2011, 12:10 PM
Duckster Duckster is offline
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Originally Posted by samclem View Post
The $1.99 kind of glasses sold in discount stores for reading.
Is your life, the lives of others in the vehicle with you, and/or others on the road only worth $1.99?

With all due respect Sam, get real. Spend the money and wear real glasses. Use your reading glasses for moderating and not motoring.
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  #6  
Old 04-17-2011, 12:12 PM
cromulent cromulent is offline
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Depends on your distance Rx. If your distance Rx is anywhere from +1.00 to +3.00, equal in both eyes, without astigmatism, then you can probably get away with this. The optics in over the counter reading glasses aren't as good as prescription specs (generally) and they're not set exactly for your inter-pupillary distance, but plenty of people drive with glasses that are not optimum.
*However*, while the reading glasses might look passably clear, remember that you might have a slightly different prescription in each eye, or some astigmatism, and these glasses won't correct for this. I wouldn't recommend just picking up some specs from the drug store and getting behind the wheel if you don't know your prescription, or how close the drugstore glasses are to your actual prescription.
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  #7  
Old 04-17-2011, 02:12 PM
thelabdude thelabdude is offline
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If you can see better at a distance with them, I guess it would be OK. If your license calls for lenses, I doubt the cop will ask to see your glasses to make sure they don't say +2, Ready Readers, or Magnivision.

I do wonder if they would improve anybody's distance vision that you need for driving.

The bad thing is that I think the machines my state uses checks near vision. I almost failed my test last time before I tilted my head to get my bifocals in use.
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Old 04-17-2011, 02:33 PM
astro astro is offline
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I can't imagine any human eye condition needing clear distance vision like driving that magnifying (ie reading) glasses would improve. It does not makes sense WRT the physics of how the human eye works.

I think you may want to make your question clearer. It does not make a lot of sense (to me) as it stands.

Are you talking about using them kinda, sorta like bifocals and perching them on the end of your nose to glance at maps and stuff while driving?

Last edited by astro; 04-17-2011 at 02:35 PM..
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  #9  
Old 04-17-2011, 02:42 PM
SeldomSeen SeldomSeen is offline
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Quote:
Originally Posted by astro View Post
I can't imagine any human eye condition needing clear distance vision like driving that magnifying (ie reading) glasses would improve. It does not makes sense WRT the physics of how the human eye works....
....Are you talking about using them kinda, sorta like bifocals and perching them on the end of your nose to glance at maps and stuff while driving?
This is how I read the question, and I agree that's the only way they'd be useful. FWIW, this is what I do while driving. It helps to read the instrument panel as well as maps etc. My close-up vision has been going south for several years now, while distance vision is as good as ever, maybe even getting better. Never been fitted with prescription lenses, I get by just fine with the drugstore-type glasses for reading, computer work and any close-up work.
SS
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  #10  
Old 04-17-2011, 04:26 PM
cromulent cromulent is offline
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Originally Posted by astro View Post
I can't imagine any human eye condition needing clear distance vision like driving that magnifying (ie reading) glasses would improve. It does not makes sense WRT the physics of how the human eye works.
Sure it does. There are people who require "plus" lenses, i.e. the same lenses you get over the counter at Rite Aid, to see clearly. These people are called "hyperopes," meaning that they are farsighted. Your mistake is assuming that reading glasses simply magnify and do not refract. All plus lenses magnify and refract light. However, since reading glasses are intended for, you know, reading and not as prescription lenses, they are not going to correct the majority of hyperopes, who will have slightly different prescriptions between each eye and/or astigmatism.
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  #11  
Old 04-17-2011, 05:26 PM
Al Bundy Al Bundy is offline
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MIght help....

Might help you read that negligent driving ticket you end up with after the crash.

If your distant vision is that bad, get a cheap prescription somewhere and order glasses off the Internet for about $35. Or go to Wal-Mart.

PS: You could download an eye chard from the Internet keeping in mind the size of letters and the distance shown on the chart. They you will know the extent of your vision loss.
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  #12  
Old 04-17-2011, 07:21 PM
thelabdude thelabdude is offline
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How important is it to have sharp vision when driving? After all, you should realize those fuzzy trucks will kill you.
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  #13  
Old 04-17-2011, 10:32 PM
astro astro is offline
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Quote:
Originally Posted by cromulent View Post
Sure it does. There are people who require "plus" lenses, i.e. the same lenses you get over the counter at Rite Aid, to see clearly. These people are called "hyperopes," meaning that they are farsighted. Your mistake is assuming that reading glasses simply magnify and do not refract. All plus lenses magnify and refract light. However, since reading glasses are intended for, you know, reading and not as prescription lenses, they are not going to correct the majority of hyperopes, who will have slightly different prescriptions between each eye and/or astigmatism.
Is the level of correction required by farsighted people to achieve normal vision within the correction range of cheap reading glasses? Although I am nearsighted, I have seen, and looked through a number of farsightedness correction lenses. None were remotely in the correction range of reading glasses.
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  #14  
Old 04-18-2011, 01:57 AM
Marc Xenos Marc Xenos is offline
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Originally Posted by samclem View Post
The $1.99 kind of glasses sold in discount stores for reading. These are over-the-counter magnifying glasses. What are the downsides of wearing these while driving?
What are reading glasses for? There's far vision and close vision. People, who don't need glasses, have eyes that can handle both. There are also people who do need glasses, but a single prescription still handles both. Then there are people who need glasses, but one prescription is not enough to handle both. So they use bifocals to separately deal with close and far vision.

With that out of the way, what's left? Oh, yeah, the people who can handle far vision with the naked eye, no problem. But close vision (reading) requires reading glasses. Whether you're far-sighted or near-sighted, both apply to close vision. And reading glasses won't help with your driving (far vision).

That's the general version. The technical version covers such things as the focal length of the lens. Reading glasses, that magnify, have a short focal length for a very limited range. They'll magnify things further away, but still be out of focus. Then there are additional considerations such as astigmatism, where horizontal focus may be okay, but vertical focus is compromised, which still makes everything look out of focus. Magnifying glasses are 360, which means they would correct one, but then distort the other.

For $1.99, you can try them and find out for yourself. If they do the job for you, who am I to argue with success? But I think you'll find that they don't do the job.
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  #15  
Old 04-18-2011, 02:40 AM
needscoffee needscoffee is offline
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"Reading glasses" is another way of saying "farsighted lenses". Read what cromulent wrote; he's an optician. They're not only for reading. I used cheap "reading glasses" for quite a few years before I had my prescription redone for presbyopia.

Last edited by needscoffee; 04-18-2011 at 02:41 AM..
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  #16  
Old 04-18-2011, 09:22 PM
cromulent cromulent is offline
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Originally Posted by needscoffee View Post
"Reading glasses" is another way of saying "farsighted lenses". Read what cromulent wrote; he's an optician. They're not only for reading. I used cheap "reading glasses" for quite a few years before I had my prescription redone for presbyopia.
Actually, I'm an optometry student (I'll graduate and be a full-fledged Doctor of Optometry this June.) But everything else you wrote is correct.
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  #17  
Old 04-18-2011, 09:31 PM
cromulent cromulent is offline
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Originally Posted by astro View Post
Is the level of correction required by farsighted people to achieve normal vision within the correction range of cheap reading glasses? Although I am nearsighted, I have seen, and looked through a number of farsightedness correction lenses. None were remotely in the correction range of reading glasses.
Yes, there are a number of farsighted people whose distance correction can be adequately corrected by "cheap reading glasses," although the majority of those people will not be perfectly corrected by such glasses.

I think people in this thread are confused by what it means to have two different prescriptions (for both distance and near.) Consider the following:

Let's say you're lucky enough to have a distance correction requiring the following prescription:
Right eye: +2.50
Left eye: +2.50
Then, you can indeed go to Rite Aid and pick off a lovely pair of specs, off the rack, and see clearly in the distance. The optics of the plastic reading lenses may not be perfect, and they may not be set for your inter-pupillary distance, but despite all that, you can probably see 20/20 through them.

What if you, with the previously listed prescription, need reading glasses? If you are an older presbyope (let's say, 60+), you'll need the extra focusing power of +2.50 diopters on top of your distance prescription. So, you require +2.50 for distance, plus +2.50 for near, or in other words a total of +5.00 diopters for reading.

What about the lucky people who require no distance glasses? If they need +2.50 to read, then +2.50 Rite Aid (tm) specs will work just fine for them for reading...but not, of course, for the distance, where it will simply make them blurry.
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  #18  
Old 04-18-2011, 09:33 PM
cromulent cromulent is offline
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Originally Posted by cromulent View Post
Actually, I'm an optometry student (I'll graduate and be a full-fledged Doctor of Optometry this June.) But everything else you wrote is correct.
Um, except for one other thing... I'm a she Not sure why I didn't catch that the first time around.
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  #19  
Old 04-18-2011, 09:56 PM
voltaire voltaire is offline
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Originally Posted by cromulent View Post
Um, except for one other thing... I'm a she Not sure why I didn't catch that the first time around.
Maybe you need your eyes checked?
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  #20  
Old 04-19-2011, 12:19 AM
needscoffee needscoffee is offline
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Originally Posted by cromulent View Post
Actually, I'm an optometry student (I'll graduate and be a full-fledged Doctor of Optometry this June.) But everything else you wrote is correct.
Sorry! I was too lazy to go look up previous threads. Do you have all the skills of an optician as well as an O.D.?
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  #21  
Old 04-20-2011, 07:15 PM
cromulent cromulent is offline
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We learn a ton about fitting frames, dispensing lenses, and ophthalmic optics in general. So in that sense the training overlaps.
We learned absolutely nothing about edging lenses or the actual mechanics of sticking the lenses into the frames.
I think most opticians would be able to take an edger, a lens blank, and a frame, and produce a pair of spectacles that you could wear. I can't do that, alas! (I'd love to learn though, as it seems like a useful skill...)

Last edited by cromulent; 04-20-2011 at 07:15 PM..
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  #22  
Old 04-20-2011, 11:52 PM
brocks brocks is offline
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Originally Posted by astro View Post
I can't imagine any human eye condition needing clear distance vision like driving that magnifying (ie reading) glasses would improve.
More things in heaven and earth, Horatio. I do it all the time. I was born very near-sighted, had my eyes corrected with RK when I was about 30, and then presbyopia hit me at 45. I wear the same reading glasses all day, and they work for reading, TV, driving, stargazing, etc.
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  #23  
Old 04-21-2011, 09:28 AM
Tom Tildrum Tom Tildrum is offline
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Spend the extra money for the peril-sensitive ones.
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