Phosphor impregnated resin for printed lighting


#1

This weekend I spent my time playing with my form1+ and phosphor powder. It went well.

I was first attracted to the idea of SLA because how clear a print could be. Clear prints quickly brought me the idea of light pipes and lens. Both have articles written on them. So lighting/optics has been on my mind for a while now with regards to a potential printing project. Recently, however, I’ve been very interested in the idea of using phosphor to convert blue light to white light.

My goal was to print a phosphor impregnated object that I could use to convert blue light to white. I knew the best resin to fuse with phosphor was going to be clear and I had already bought some phosphor and a high powered 445nm laser. My first question at this point was how much phosphor to clear resin should I mix.

To study molar content, I designed a small test tray that I could use to make 8 different sample in small batches and see how the mixed preformed. This was also a test in itself because I was using the sun to cure the resin which I’ve never done before. I held the resin constant at 1cc and started with 0.2g and stepped up the mixture by 0.2g at a time.

I learned that phosphor will settle quickly on the bottom. because it settles It seams a high phosphor content is best, the closer to saturation the better. However, Because our printers print upside down if the mix is not fully saturated then it still settles on the bottom where the printing is taking place making it still work, but full saturation would guarantee a consistent phosphor content across a print.

Over all the test was successful (although the print partially failed.) because I was able to print a phosphor impregnated filter. it has been a really fun past 48hrs and I am excited to keep working with this tech on future projects. I believe that the combination of light pipes, lens and phosphor filters all printed can make for some really cool prints!

I’m trying to keep this post short so I have left out a lot of details. If anyone has any specific question feel free to post below and I’ll get back to you. Thanks!






Can we print a flashlight?
#2

I’m sorry in advance because I must be missing something really obvious!

What is the need to convert blue light to white light? Just curious.


#3

That’s a really good question. I’ll admit to being a little too focused on this project. Focused to the point that I forget why I started.

It’s useful to to convert blue to white because it’s not easy to make white light from LED’s or in my case a laser. Even if you look at white LED’s you’ll notice that there is a yellow layer on top, that’s phosphor. So my hope is to be able to print phosphor diffusers for custom lighting. An example can be found on Philips 12w LED bulbs:

A tear down can be found here.


#4

Did you just use the clear setting on the form1 with the mixed resin/phosphor? I’ve been curious lately about mixing pigments into the clear.


#5

Oh that’s interesting. I didn’t even realize products like that existed!


#6

@Jason_Pease, I used clear at 0.1 mm version 02. I really didn’t do anything special to get the resin to cure, even with the phosphor.

A little off topic, but I was worried that the formlabs 405nm laser would be close enough to the phosphors excitation frequency at 445nm. But while printing I didn’t notice any extra light and more importantly the print quality seams pretty good!

@Anthony_Huczek I’m glad you asked that question! If you look around Google you can find other examples of using this stuff. My personal favorite is BMW/AUDI’s research into laser headlights :smile:


#7

SCIENCE!!!

(Sorry … I couldn’t resist … Nice experiment!!!)

-sj


#8

HAHAHA You have just made my day!


#9

Cool glad I found this, giving me ideas too, heck I love Science!