Well, not really sunglasses, but rather clip-on shades for my 3D-printed glasses
But here's the thing: they're FULLY 3D-printed. The "lenses" are in fact the finest and thinnest mesh I could print with our printer - basically one 0.1mm layer of 0.4mm lines spaced 0.4mm running horizontally, and an identical layer of lines running vertically right on top of it.
Is it perfect? No. The image through it is kind of "pixelated" But it's surprisingly acceptable. It looks like this when looking through them:
In real-life, it's quite a bit darker than this. But the photo shows fairly accurately how it looks like seeing through them.
It works because the mesh is very close to the eyes and totally out of focus. And although it's not optical-grade, the price is unbeatable π
If you want to try printing it yourself, the model is here. It's meant to be printed with a 0.4mm nozzle and a 0.1mm layer height - including the first one.
Double-check how the slicer slices the first two layers, where the mesh lives, because it easily tends to "simplify" the lines by not printing them, which is obviously not what you want.
EDIT: as others have pointed out in this thread, don't use these shades as actual sunglasses without sticking some UV filter over the mesh on the inside. They're not eye-safe as-is. I made them more for the challenge of making them than anything else.
Sorry to be that guy, but be careful with these. Everything will seem darker, so you won't shy away from the sun as much, but you still get UV in your eyes, which can damage them. They look really cool though!
Aye, this is the exact problem that early sunglasses that didn't block UV light had. Wear ones that offer UV protection! https://www.aao.org/eye-health/tips-prevention/sun https://www.aao.org/newsroom/news-releases/detail/seven-myths-about-sunglasses-could-damage-vision
Idk anything about 3D-printing, just came in from the main page to give a heads up. But maybe these could be fitted with UV filtering foil or even lenses? They make thin ones you can cut to shape (I have clip ons like that).
You could definitely do a UV layer just stuck on the inside with an adhesive, but I get the feeling that OP likes the idea of them being "totally" 3D printed
Indeed, it was for the challenge. Modeling this is surprisingly CPU-intensive and printing it is a bit finicky to get right.
Yes, it will be 50% (looks like half mesh) darker to visible light so your pupils will dilate and allow even more UV light in than if you didn't wear them. What isn't mesh lets UV straight in. Whereas sunglasses block 100%.
I'd call those Cataract Glasses instead of sunglasses.
Wouldn't it block 50% of all light, UV included?
Pla plastic typical in 3d printing lets 95% of UV-C light through. So it looks dark to your eyes but is transparent in the UV spectrum.
https://www.mdpi.com/2504-477X/7/10/410#:~:text=The%20optical%20resistance%20of%20PLA,of%20ultraviolet%20light%20is%20transmitted.
Also a pupil dilated has an area of 12 mm^2. A contracted pupil has an area of 3 mm^2.
So it's 4x more uv light coming in than if you didn't wear them.
These sunglasses are far more dangerous than not wearing sunglasses.
75% actually. Each layer lets half the light thru, so it lets half of half thru in total.
But yeah, like others said, that doesn't make it safe.
Pla is transparent to UV-C. (The cancer causing UV). So your sunglasses trick your eyes into dilating and allowing more UV in.
Yes. This isn't as bad as the dark lenses without UV filtering that people are throwing around.
But it doesn't reduce the UV incidence either.
I added a warning note to the relevant paragraph on my Github. Thanks!
since they are physically blocking light, shouldn't these block uv by the same amount it blocks all other light?
Sunglasses are often coated with special filters to block more UV light than other parts of the spectrum, e.g. 90+% of UV, but only 75% of visible. These glasses would block all light in (very roughly) even amounts. To achieve similar protection you would barely be able to see.
The wavelength of the light both influences what materials they penetrate and at what angle they get scattered. Can't speak for this particular material, but UV has a smaller wavelength than visible light, which gives it a smaller scattering angle. So it gets scattered more all over the place and makes it around little corners more easily. And you'll never be able to tell whether or not it was dangerous because you can't sense UV in any way.
I wanted to see if I could make something that works out of nothing other than PLA rather than actual, good eyewear.
I live way up north in the boonies so it's not like we get massive amounts of sunshine here. And there's always the trees to provide shade. But they might come in handy every once in a while in the summer.
They'll let UV through but no more than 25%, since that's the amount of light the mesh lets through. But hey, for the price, I can't complain π
Also, I suspect the PLA will crumble very quickly if it's hit by enough UV to damage my eyes...
Please don't actually use them as sunglasses. You can buy cheap UV film online that you can stick on em. Hell, any pair of cheap sunglasses is usually UV coated.
As the above user already said, your pupils will dilate because they will think there's less light, letting more UV in. At best, it will cancel out whatever is blocked by them. At worst, you will end up with more UV reaching your eyes.
Cataracts can only be treated by surgery. Please don't cook your eyeballs, especially when you can so easily have complete UV protection.
Acknowledged π
Wouldnβt their regular glasses block the UV still though?
Hmm yes, you're right: my regular lenses do have an anti-UV coating on them. I clean forgot about it.