Can we print a flashlight?

Ever since trying to print phosphor impregnated resin I wanted to try to print something to showcase this idea. So I thought, I could I print a flashlight?

I wanted to test the idea quickly so I developed a phosphor element that could fit inside a maglight.

The printed assembly is 2 part. A phosphor element and a light pipe hold. My hope is that the light travels up the the light pipe and activating the phosphor. The phosphor then would shine on the maglight reflector and the rest would work normally.



So how well does it work?

I would say that it was a slight susses. It did produce white light but it wasn’t very focused and the light pipe introduced too much blue to the maglight reflector.

I was curious what the lightpipe looked like by itself so:

and with the phosphor element:

To rap up I think there is some potential to optimize the prints to make this actually work. For my next attempt I don’t think I’m going to include a lightpipe. I think a thin file phosphor element would work better.

Please let me know what you think and any suggestions! I’m new to optics so I really am just taking stabs in the dark (pun intended).

Thanks everyone!


I’ve spent my time revising my flashlight design since my last post. I have had enough success to want to share my updates with you guys!

I made 2 different designs: reflection type and through type. In the picture below you can see the 3 different revisions. From left to right you have rev 1 (as seen in last post), through type element, and reflection type element

The through type is a thin filter like phosphor element. At it’s thinest it’s 300um. The hold (printed in black) is essentially the base of the light pipe seen in rev 1.

The through type worked better then rev 1 and was good enough to look like a flashlight!!! The issued I had with it was that the light came out yellow.

The reflection type is similar to rev 1, however, I didn’t use a light pipe. The hold mounts to the top of the element.

The reflection type worked really well :slight_smile: It was bright, very white light, and wasn’t as sensitive to heat as the through type element. I did notice that the element wasn’t fully set in the focal spot of the reflector, but something for the final revision!

Thanks for checking out my progress. As always questions are welcomed!


In order to work, the clear resin has to have UV blocking elements in it, so as the laser doesn’t penetrate too far when you make each layer, so I am not too surprised the light pipe wasn’t successful. The non light pipe version looks awesome!

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@Andrew_Miller, Could I ask you to elaborate on why having UV blocking properties would help? Sorry I’m very new to lasers, optics, light pipes and the sorts so I’m struggling to understand.

Is the idea that less penetration from the laser would reduce layer height making less/finer imperfections for the laser to reflect off of?

Also thank you for the comment and compliment!

@kelly_ma way to join the community.

In the future, please be more constructive.

Sorry my comment was badly phrased. In order to work as a resin in the printer, it has to have UV blockers.
The blockers allow you to cure only the one layer at a time, stopping the beam penetrating deep into the resin bath.

This unfortunately means that it is unsuitable for use as a UV light pipe.


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Thanks for the clarification @Andrew_Miller.