[Florian] is hyped for Google Cardboard, Oculus Rifts, and other head mounted displays, and with that comes an interest in lenses. [Floian] wanted to know if it was possible to create these lenses with a 3D printer. Why would anyone want to do this when these lenses can be had from dozens of online retailers for a few dollars? The phrase, ‘because I can’ comes to mind.
The starting point for the lens was a CAD model, a 3D printer, and silicone mold material. Clear casting resin fills the mold, cures, and turns into a translucent lens-shaped blob. This is the process of creating all lenses, and by finely sanding, polishing, and buffing this lens with grits ranging from 200 to 7000, this bit of resin slowly takes on an optically clear shine.
Do these lenses work? Yes, and [Florian] managed to build a head mounted display that can hold an iPhone up to his face for viewing 3D images and movies. The next goal is printing prescription glasses, and [Florian] seems very close to achieving that dream.
The last time we saw home lens making was more than a year ago. Is anyone else dabbling in this dark art? Let us know in the comments below and send in a tip if you have a favorite lens hack in mind.
Dutch company: world leader in 3D printed optics http://www.luxexcel.com
And as far as i know the only one, apart from a lab research by Disney http://www.disneyresearch.com/project/printed-optics/
I have a sample from them at my company (from some month ago), i was somehow a bit disappointed, the quality is good, but you can still see the layers, so not suitable for imaging, only for lighting.
http://smallerandupsidedown.com/
and their instructable.
http://www.instructables.com/id/Making-Custom-Lenses/
http://smallerandupsidedown.com/ did similar work.
Whoops, sorry about the double post. Thought the spam filter caught the one with two URLs in it and it didn’t seem to post.
I’ve been working on making lenses but more importantly a clear mk 43 faceplate so I am no longer poor peripherals man. some of my lenses are on thingiverse and pictures on my deviantart
wow thats amazing the resolution must be ginormous, unless its some nifty trick.
woopssorry i actually read – yes its not purely a printing process.
An “hack” from taulman ( http://taulman3d.com/t-glase-optics.html ) allow you to smooth the outside layer with epoxy, but it could be interesting to see with a thicker print, and the optical drawing are wrong (with this product on the surface, the reflections inside each internal layer also magically disappear).
I also want to use poured silicone to make some try, but i was more thinking of using Moldlay ( http://www.formfutura.com/175mm-moldlay.html ) which is suppose to work with silicone, and rather trying to smooth it before pouring.
CYA, for experimental use only. The feds and the optometry industry will come after you.
Watch out, Jacquard’s upset weavers might knock that tinfoil hat clean of your head.
Hmmm – 3D printing and achieving and optically “clear” finish are almost not even worth a mention when making an optical lens or mirror.
For a lens or mirror to be any actual use, (as opposed to just the lens looking clear and shiny in a photo of the lens), the aberration, or differences in the lengths of the possible optical paths the light takes, must amount to no more than 1/4 wavelength. That means at most half that, or 1/8 of a wavelength error between the actual shape the lens, and what the shape should be. That’s VERY SMALL.
If we make it as easy as possible with very red light (largest wavelength), that’s 1/8 of about 750nm, or about 90 billionths of a meter error, or 3.5 millionths of an inch in imperial measure. For other colours, a lot less less.
Apart from some outside YouTube links, he doesn’t explain how he achieves this accuracy, and makes, well, a lens.
References: Lord Rayleigh’s 1/4 wavelength criterion:
http://www.telescope-optics.net/effects1.htm#In_1878
https://books.google.co.za/books?id=2lIwU313wgkC&pg=PA24&dq=%22Rayleigh+criterion%22+1/4+wavelength+%22acceptable+images%22&hl=en&sa=X&ved=0CBsQ6AEwAGoVChMInqGFgaWDyQIVA4IPCh0sEgFU#v=onepage&q=%22Rayleigh%20criterion%22%201%2F4%20wavelength%20%22acceptable%20images%22&f=false
The most surprising takeaway from my little project has been how compliant the human visual system is. I’m 100% with you that these hand polished lenses aren’t accurate enough for modern telescopes. Period. We’re on the same page with the physics. However, eye prescriptions are written in increments of 0.25 diopeter, which is the inverse of the focal length in meters, corresponding to over 2cm tolerance in radius of curvature! That’s massive even for my finger. Even with 220 grit sand paper, I’m removing 2mm maybe.
IMO we often forget that people have worn eye glasses for hundreds of years and they were REALLY poor by today’s standards.
“not even worth a mention when making an optical lens” — that stings, dave. I made functional lenses with a consumer 3D printer and my friends and I continually experience VR with said lenses. I guess people on the internet should just be quiet so you can read things of “actual use.”
Despite the boohoos, if you continue to tweak the design and process, you will pave the way to a world of custom optics. Just because it isn’t made of glass doesn’t make it useless. I do believe glass is by far superior to any plastic or resin based lenses, but glass is difficult to work with. If you screw up, you have to start over from a fresh round. With this, you just have to start over from the nearly finished rough copy.
Might be cool for making optics for a uv-curing resin printer.
I do believe this is already being done, and some pretty wild things are coming from that. I believe Disney did some cool stuff. Others have printed an inverting lens by printing pipes that twist 180 degrees as the print goes up. Traditionally, inverting lenses are created from glass tubes that are heated and stretched in bundles till they are very thin, then they combine several of these bundles and continue to stretch, so on and so on, then they put a sharp twist on the fiber bundle and snip it. Printing would make it much cheaper and quicker.
I’m currently working in a project that aims at printing magnifying lenses with a DLP homemade 3D printer:
https://github.com/bqlabs/microspot/wiki/3D-Printing-lenses
It’s still just experiments, but it has potential.
I bet you’d have better results by 3d printing a lens grinding machine.
Strangely enough just today I was thinking about printing out a VR headset and pondered whether or not it was possible to print out lenses for the headset as well…
Different method, but still cheap and DIY, as well as ADJUSTABLE!
https://www.ted.com/talks/josh_silver_demos_adjustable_liquid_filled_eyeglasses
Objet has a clear material for their printers which has been used to print lenses. If you have a good lens you can use an RTV silicone to make a mold from it then cast copies with an optically clear, hard urethane resin like Smooth On Crystal Clear. It has to be cast under pressure to not get bubbles. You can try vacuum degassing after mixing the resin but that’s not doable for the faster setting versions.
I also cast my silicone molds under pressure so they have no bubbles and the silicone gets into every nook and cranny of the master item.
Id forgotten about casting. With a good enough master you can avoid almost all the need for polishing. I worked for a place that would cast complex fresnel lenses.
Beware! Remember the Opti-Grab!
if you’re gonna be doing all the polishing and grinding anyway, why not just start with a circle of clear acrylic? There are “good enough” optical grade sheet plastics available at places like TAP and only need a circle cutter to get started.
cutting a lens profile with a light hobby lathe or rotating tool is relatively simple once you have practice. You’ll only have to worry about lens shape and exterior distortion instead of any optical rippling inside the 3D printed material.
Again this is only “good enough” for emergency eyesight/optical use.