Did they know about the law of diffraction, or did they just grind the glass until it had the desired effect?
Early printed book contains rare evidence of medieval spectacles (2012)
21–30 of 35 posts
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#22Earlier quoted context omitted.
Shouldn't that be "absque oculis" instead in that interpretation?
> From an earlier orbus ab oculīs ("deprived of eyes"). > (Late Latin) blind https://en.wiktionary.org/wiki/ab_oculis
I don't think that link to "ab oculis" is relevant. I suspect that "ab" just means something like "on, in front of" in this case: "glasses in front of the eyes for reading".
If you have time, check this article for the various possible meanings of "ab": http://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:19... (It's a bit more detailed than wiktionary!)
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#23Amazing that glasses was invented almost thousand years ago, and today it is still that overly expensive item. I only need glasses since the last year or so and I have been amazed by how monopolistic and bad this whole industry is. The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. The price of the lens mounts is just ridiculous for a piece…
Most eyeglasses cost under $10 to make, lens included. It's still an expensive item thanks to the near monopoly of both frame and lens production. Nearly every brand you know are owned by just two companies. Those two are now merging: https://www.theguardian.com/news/2018/may/10/the-invisible-p...
Excellent example of the “free”economy not working toward efficiency and actively working toward concentration. We really need more,checks and balances.
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#24Amazing that glasses was invented almost thousand years ago, and today it is still that overly expensive item. I only need glasses since the last year or so and I have been amazed by how monopolistic and bad this whole industry is. The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. The price of the lens mounts is just ridiculous for a piece…
Repeating a sibling comment[0] here to donate to https://onedollarglasses.org/
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#25Amazing that glasses was invented almost thousand years ago, and today it is still that overly expensive item. I only need glasses since the last year or so and I have been amazed by how monopolistic and bad this whole industry is. The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. The price of the lens mounts is just ridiculous for a piece…
> The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. Depends on the country. I went to Japan for vacation a few months ago ; my girlfriend wanted a new pair of glasses. She just went to a mall in an optical center, they took her eye measurements on the spot, we went back two hours after and the glasses were ready.
most apothecaries here in Italy have a section for cheap glasses. worst scenario you have to buy two and mix the lenses.
if you have special issues and need to order lenses it may get expensive but glasses are deductibles, so you get a little back.
anyway I did a cursory search on amazon usa and one can find prescription glasses with lenses of variable strength for around 20$, of course they're not the best or the prettiest, but there are ways for people to get glasses on the cheap.
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#26Amazing that glasses was invented almost thousand years ago, and today it is still that overly expensive item. I only need glasses since the last year or so and I have been amazed by how monopolistic and bad this whole industry is. The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. The price of the lens mounts is just ridiculous for a piece…
> The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. Depends on the country. I went to Japan for vacation a few months ago ; my girlfriend wanted a new pair of glasses. She just went to a mall in an optical center, they took her eye measurements on the spot, we went back two hours after and the glasses were ready.
I did the same when I had to travel to Moscow the day after I had lost my glasses in the ocean from a boat.
Going into a shop in Stockholm I was told it'd take 2 weeks, which obviously wasn't acceptable.
When I arrived in Moscow, just like you I went into a shop, took the measurement, went for lunch and it was ready when I came back. What was fascinating was that they had the actual machines to grind the lens at the back of the shop. It was pretty cool.
Those glasses lasted me for years, and they worked really well.
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#27Earlier quoted context omitted.
Would you mind sharing a link to the vendor where you got the Chinese glasses?
Not the original commenter, but my wife and I have had several pairs from http://zennioptical.com and been very happy with them. (And speaking just for myself, I'd prefer not going through Amazon if it can reasonably be avoided.)
Seconding the Zenni recommendation.
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#28Earlier quoted context omitted.
Would you mind sharing a link to the vendor where you got the Chinese glasses?
Not the original commenter, but my wife and I have had several pairs from http://zennioptical.com and been very happy with them. (And speaking just for myself, I'd prefer not going through Amazon if it can reasonably be avoided.)
I love Zenni. I buy glasses from them quite a bit just for a change of look. I think the cheapest I've been able to buy them for so far is about $10.
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#29Earlier quoted context omitted.
Most eyeglasses cost under $10 to make, lens included. It's still an expensive item thanks to the near monopoly of both frame and lens production. Nearly every brand you know are owned by just two companies. Those two are now merging: https://www.theguardian.com/news/2018/may/10/the-invisible-p...
Excellent example of the “free”economy not working toward efficiency and actively working toward concentration. We really need more,checks and balances.
Yup.
The Freedom Markets™ cult perpetuates the fiction that corporatism == capitalism.
Corporations are explicitly anti-competition.
Re: Early printed book contains rare evidence of medieval spectacles (2012)
#30Amazing that glasses was invented almost thousand years ago, and today it is still that overly expensive item. I only need glasses since the last year or so and I have been amazed by how monopolistic and bad this whole industry is. The prescriptions are fairly standard, but still, making a pair of glasses cost more or less 200$ and require a 1:1 appointment. The price of the lens mounts is just ridiculous for a piece…
I wonder if part of it is that psychologically people want expensive glasses because they value their vision and want to look cool? I use a 99p pair of reading glasses from the pound shop and they actually work surprisingly well and look ok.
It's sold as a fashion item now. Why else would pro athletes with superb vision wear fake glasses? Handbags also cost little to make, same difference.