Eyeglasses with frames welded to the lenses would be kinda cool, and may even justify current commercial price points (not that they would be sold for them).
Most eyeglass facilities also would not touch used frames, given the potential for frames pre-existing damage and wear, and how that creates liabilities for the lab while installing new lenses.
I have changed my lenses three times on my current frames, never had any issue, never heard of anyone warning me of such a thing. My whole family does that.
Sounds like your eyeglass facility really wanted you to buy new frames.
The vast majority of Rx eyeglass lenses are various forms of plastic now (CR39, polycarbonate, etc). True glass Rx lenses are still available but very few labs process them and even fewer doctors recommend them.
I’ve tried to change lenses while keeping frames, most manufacturers make it pretty hard to do so. Some don’t sell blank lenses without frames, and others have such fragmented and changing product lines that lenses aren’t available 1-2 years after original purchase. And to be fair, frames aren’t really all that durable anyways, and for something used daily it’s not all that wasteful to replace them every once in a while
That's not how eyeglasses work. Lenses are supplied to opticians as a round blank, which are then cut to fit the frame. Any optician should be able to re-glaze any frame, regardless of age or manufacturer; their equipment measures the frame, then cuts the lens to fit. It's really quite impressive to watch:
Things are changing again. My optician used to work as you described, but for my last set of glasses I would choose the frame and he would enter my lens specification into the manufacturers webpage. The manufacturer (a German brand) with a Singapore factory would produce then the desired frame and equip it with the fitting lenses and send off the bundle to my optician here in Germany. As I had the same lens specs as my previous glasses, I can say that the new glasses are optically superior and the whole package was even distinctively cheaper than the previous one.
Still the same concept though, just moved: the Signapore facility still starts with a round blank and grinds it to "whatever is required", so you can fit any lens to any frame still.
Well my experience above was with Costco optical and Kirkland branded frames, a Luxottica brand frame through a small independent optician, and Warby Parker. Maybe they were just blowing smoke to drive sales of new frames? I dunno. The one time I did get new lenses, they didn’t fit quite right and always looked a little “off”.
That's really strange. I did replace my lenses and kept the frames. It was basically the same procedure as ordering new glasses.
To my knowledge opto-technician will map and cut new lenses using your frames or old lenses as a template.
Also looking at the prices, it looks to me that most of the profits are in selling the lenses (unless you buying designer frames for gazillion $). Where I live no-name frames are very often free or for extremely low price (< 30$).
EDIT: also it would be an insane task to mass manufacture specific lenses for specific frames, just due to the fact of variability of eye conditions: near-sightedness, far-sightedness, astigmatism and varying strength on these conditions (cylinder angle and diopter).
I've even had an optician replace the lenses in glasses I just purchased with ones made from a different material. (I don't remember the materials involved, but I was getting chromatic aberrations in the first one.)
I'm confused, at my local optician I just point out a frame I want and he either pulls my measurements from his system or re-measures me and tells me my glasses will be ready in a few days. Hell, one time I had a frame that constantly bent and they ended up just letting me pick a new frame with almost identical glass slots and he just polished off a tiny bit until the glasses fit the new slots. How does the manufacturer fit into any of that?
Well the line that has been told to me is that they receive lenses and frames together, and they can’t sell me the lenses without the frames because then they’d have a frame without lenses. Essentially putting the onus on the manufacturer for why they can’t do it.
Hm? It was my understanding that the companies that sell frames and the ones that sell lenses are mostly independent. Your optician will cut the lenses to fit in your frames.
I've had the same Nike frames for probably over 10 years now and the previous ones (same brand & style) for about 5 years until I broke them. My prescription changes very slowly, so I've only updated the lens once. But except for that one frame breakage, I actually have every eyeglass frame I've ever purchased since I first got glasses in 1993.
When I hear people talk about all the expense and trouble they have getting prescription glasses made for them, I'm so glad I just use contact lenses. I have no idea why people subject themselves to so much trouble, all so they can have a clunky, obsolete device that's been around for centuries sitting on their nose.
Yes I believe in the mantra as well however you will hardly convince me this applies to a frame and lens. Yes it may be less time consuming for the purchaser to just grab a entire new pair off the shelf but someone had to dig out the ore to get to the metal to and someone drill out gas to move the ore around and so forth you get the point. As we know global climate change is real, and I have children who I leave this earth, surely on a global scale, me replacing the glass in a frame is less wasteful for everyone's time. But I only reply because you said 'human time' vs something like 'if it saves my time'. Most of what we consider to saves our personal time is at a considerable cost to the environment, and other peoples time. We destroy the environment so my kids can spend their time cleaning it up in the future. What a screwy way to live.
Worrying about discarded eyeglasses as an "environmental impact" issue is a classic example of bikeshedding.
I'll burn more gasoline driving home from work than the mass of a pair of eyeglasses. And I'll burn it in a car that has a 10-15 year lifespan and weighs about as much as 100,000 pairs of glasses (I'm guessing here, but it's at least in the tens of thousands).
Bikeshedding for purpose of condescension is one of the biggest and most avoidable sins of environmentalism. Don't do that.
While I was replying in a thread that started about wasting frames for glasses, the parent poster seemed to have gone on a tangent about resource waste generally being insignificant next to human time costs. I did not mean to contend that saving the wasted glasses frames was needed.
I have confidence humanity will solve the disposal issue soon enough no hand wringing will be required. See: rapid renewables deployment across the globe and the hockey stick EV adoption curve.
It’s not as if this is nuclear waste. Toss it in the ground, wrap it up nicely, and we’ll revisit it in 50-100 years.
>>I have confidence humanity will solve the disposal issue soon enough
Hubris my man. Pure hubris. I'm not saying it's not possible, but when there are strong financial interests tied to NOT doing exactly that, it doesn't feel like something I'd say I'm confident in.
Also "soon enough" to undo all the damage that things like the Pacific Garbage Patch have done to the environment? Soon enough to remove all the mercury in food chain? There's literal things dying because of this. I think the hand wringing is justified. You can make it a value prop (we save X human lives because of products packaged in this manner, so fuck these bees) but there's still actual consequences to our planetary roommates.
One person's hubris is another person's faith in human ingenuity.
Your pacific garbage patch example is disingenuous. It would not occur if poor countries had proper waste disposal infrastructure (ie collection and landfills).
>> It would not occur if poor countries had proper waste disposal infrastructure (ie collection and landfills).
Sure, and if we just provide food for everyone then nobody will be hungry.
That's some high quality hand waving there my friend. The whole "don't worry, we'll figure it out" attitude just comes across as useless. There aren't realistic solutions in place right now. People are working on solutions though. This doesn't mean that there's any reason to assume these solutions would work on a global scale.
When dealing with problems like this, we're going to require extraordinary solutions. Confusing "possible" and "probable" is my issue here.
Sounds really interesting. The only potential downside I see is that metal and glass generally expand differently under heat and have different tensile strengths etc. I wonder how they plan to deal with that.
Plenty of glass to metal sealing is done for hermetic purposes. One use is glass sealed connectors for aerospace use. Also components for ultra high vacuum systems which use metal to glass (or ceramic) joints to transition between materials or electrical isolation.
Generally these metal-glass joints use a sealant that also acts as an expansion joint. The California Academy of Sciences (that building with the grass on the roof with the circular windows) has a rainforest sphere made out of 8x8 foot panels, if you inspect the joints they are sealed with 1" of silicone caulking to account for different rates of expansion of the glass in four directions. This silicone caulking is almost the consistency of chewing gum.
Without that expansion joint, directly welded together, I'm curious how say, a Pixel 3 with the screen welded to the metal case would do. I can imagine a situation where the case and screen expand differently and end up cracking the screen.
No, there are special alloys and techniques for directly bonding metal to glass. In a lot of cases the approach is to keep the bonded area close together to minimize the distortion of the metal from the different expansion rates.
Materials like Kovar are designed such that it very closely matches the expansion curve of glass so that it forms a hermetic seal without any kind of sealant between the glass and the metal.
Not in Ultra High Vacuum systems. There's no surface on the inside except glass or metall that can be outgased for some time at high temperature.
Since we need to heat the system to speed up the outgasing process, the expansion coefficients for the joints between metall and glass must be very closely matched.
They don't specify anything about the nature of that weld though, for example how big the glass and the iron pieces were, and whether it was a point weld or a continuous weld, and the geometry of the weld itself (for example if it had an inside/outside corner).
They also didn't mention if it was heated evenly or not.
This sounds like a "we have to hype up the practical applications of our research because that's what you do if you want more funding for next year" type of article. They don't even include hypothetical example applications.
I also wondered about this. Seems like it has to be taken into account.
Still, the article says that glass and metal are already put together with adhesive. Unless the adhesive is stretchy, it must mean that, within certain limits, it's already OK. Presumably it gets worse as the length increases since expansion is cumulative, which suggests that smaller lengths are OK.
Also, there are probably ways you can design around it like creating gaps in the metal or shaping it so that the metal can bend.
Isn’t that the whole reason this is a breakthrough? It’s even discussed in the article...
Professor Duncan Hand, director of the five-university EPSRC Centre for Innovative Manufacturing in Laser-based Production Processes based at Heriot-Watt, said: “Traditionally it has been very difficult to weld together dissimilar materials like glass and metal due to their different thermal properties - the high temperatures and highly different thermal expansions involved cause the glass to shatter.
I think it depends on the application and scale whether or not that is an issue.
For joints that are intended to remain at a constant temperature, no problem. For very small structures where thermal expansion amounts to very little relative displacements, also no problem.
But, yeah, this isn't a solution for joining outdoor windows to metal frames.
Just because a test joint of unknown size and shape held up over that range doesn't mean an actual real world assembly can hold up over that range. We know nothing about the nature of the weld they tested or the nature of the testing. Even with two of the same materials it's very possible to design a joint that doesn't work very well in the real world.
The glass-metal weld itself might be perfectly fine!
The glass portion, however, could crack depending on its size/geometry and the temperature change.
The article doesn't make clear exactly what kind of manufacturing operation they're intending. I suspect this is a technology to replace glue/epoxy in certain scenarios where one joins metal and glass.
That would work in much of the world on paper. Not that the world sees the upper range as ambient. The metal may well approach the upper range during a sustained heat exposure.
Wonder what the safety factor actually is?
There are three basic types of temperature exposures:
One, a journey. Got super hot, or cold for a while, then returned to moderate, or acceptable range.
Two, excursions. Got extreme and stayed there for a non trivial time. (Scaled to the properties of whatever it is)
Three, wild ride! Journeys all over the place.
In addition, these can be one off events, or cyclic.
Windows get a kind of cyclic ride in many places. A bond holding "for a while" always has the question of what "while" really means.
Microfractures due to highly localized stress and strain, pre loaded in as an artifact of welding, would be my primary concern.
Even in that range, you can run into issues. I know of local buses in my home town where a lot of them would have cracks in the front window because when they went over speed bumps, the frame would flex enough that strain was placed on the window. If you remove the silicone glue or whatever it is they use to afix windows, this problem would get a lot worse.
Interesting. I wonder if an architect/civil engineer could explain what the implications would be of the application of this technology in the field of construction?
Steel structures deflect a lot more than glass and buildings are built to relatively loose tolerances. E.g. skyscrapers have flexible neoprene gaskets between glass cladding panels to allow for a few mm of structural deflection due loads caused by wind, thermal, floor loadings and construction settlement. To give a rough idea, if you take a point on the top of a 250m skyscraper it could be anywhere within a ~300mm diameter circle due to these loads.
So while I'm not 100% sure, it sounds like this technique would be more useful for product design scale stuff like phones, nano machines, miniaturised optical systems.
This permits bonding a metal handle to a pyrex measuring cup. (It would only be safe up to boiling temperatures under the restrictions of the current process, assuming that the process described scales up to a measuring cup.)
This is a constructed example to demonstrate the type of thing that could be done now that we've figured out a possible way to do it. It's probably not a good example, but it is clearly distinct from the thin-film processes we consider common today.
EDIT: See below’s multi-paragraph writeup of why my “now you can do this” example is not a good example in practice.
One of the advantages of borosilicate glass kitchenware is that you can put it in the oven, fridge, and microwave. Bonding metal to it with a joint that only works up to 90C obviates most of that utility. The only problem with borosilicate glass vessels as they are is that they don't work on inductive cooktops.
That joint is going to have to handle 300C in order to make it into my kitchen. I might go for a glass/ceramic liner in an aluminum pan, particularly if the ceramic is BAM, but that's going to get hot.
I'd actually look for this first in LED lenses bonded to aluminum heat sinks. A good bond there might allow for higher wattage through the electronic parts. An operating range between -50C and 90C encompasses the operating range of most consumer electronics, plus some margin.
Based on their mechanical properties I don't see why the current recycling process wouldn't work.
It's not like the metal recycling industry doesn't already deal with huge amounts impurities and other material entering the process. If you happen to have tons of metal welded glass to scrap you're not going to get as much money for it because it needs more processing so it will enter the supply chain at a lower price point. It's like the difference between scrapping a car and scrapping machine shop chips.
I could definitely see the applications when it comes to optics, even just considering the assembly of camera lenses could be improved or automated more with a process like this. Maybe it could be used for automated optical alignment to improve optical quality and consistency. Current methods for doing this are very manual.
It’s my understanding that adhering steel to glass has not been an issue for some time. The issue is that they expand differently with heat. Which is why you have a rubber/flexible seal.
That's a meaningless statement without knowing what kind of assembly they built, the shape of the joint between the materials was and if the test sample was heated evenly or unevenly.
Well car surfaces (or even interior) can get hotter than that for example. Also, 1 test doesn't cover a use case of 5-10 years of daily heating and cooling down ie on a car parked outside, or darker window frame on a sunny side of building.
> At the moment, equipment and products that involve glass and metal are often held together by adhesives, which are messy to apply and parts can gradually creep, or move. Outgassing is also an issue - organic chemicals from the adhesive can be gradually released and can lead to reduced product lifetime.
Another commenter pointed to the similar implications for new iPhone models.
Unless iFixit et al releases an affordable home glass-to-aluminum welding solution, I think Apple may win the cat-and-mouse 3rd party repair game for now.
