Congratulations To The Frikkin Laser Winners!

hackaday.com

Apparently you all love lasers just as much as we do. We put out a challenge to use, build, or otherwise abuse our favorite coherent light sources, and you responded. Some of the projects had been in the works for quite a while and were ridiculously polished, some were whipped together on the fly just for the contest, and we truly enjoyed both.

We only have three $150 DigiKey gift certificates to give out, though, so without further ado, we present to you…

Our judges’ favorite project was [Jacob]’s CubeRaman, and it’s not hard to see why. A Raman spectrometer shines laser light at an object and catches the reflection, filtering all of the original laser wavelength out. What remains are photons that have interacted with electrons in the atoms that make up the target itself, and come back at a shifted wavelength. Comparing the spectrum of this Raman reflection with a database of known spectra tells you what it is made of.

This is by no means an easy project, but [Jacob]’s documentation, careful selection of parts to buy used and parts to build, coupled with a clever 3D-printed mounting system make it plausible for the home gamer. We love seeing out-of-reach science gear brought into reach, and we know we’ll be keeping an eye on this project in the future.

Next up, we had [Kyle Mayer]’s Measuring Microns with Lasers, which is a DIY laser rangefinder, but for measuring very small distances — under a centimeter — with precision. Like many laser optical rangefinders, this bounces a laser off the target and collects the light on a line sensor, using the angle at which the light returns to figure out how far the target is.

[Kyle]’s implementation uses three of these measurement heads and produces a reading that is precise down to 0.25 μm nearly 5,000 times per second. This puts it in league with devices that you have to request a quote for, so you probably don’t want to have to afford them.

And finally, an art project! [AJRussell]’s Glow Engine is a beautiful take on a familiar laser trick: shining a blue laser at glow-in-the-dark materials to leave persistent traces. Scan the laser over the phosphorescent screen, and you have something like a CRT, only in [AJ]’s case, a very very slow CRT.

The beauty here lies in the details. [AJ] chose high quality strontium aluminate for the glowing, and used high resolution encoders and the open-source SimpleFOC motor driver firmware to get the spots in the right place. Snippets of old hard drive platters make fantastic mirrors. All in all, a super implementation that we’re pretty sure looks even better in the real world.

Honorable Mentions

We always come up with a few honorable mention categories to give you all some inspiration. And it also gives us a nice excuse to feature some more sweet projects.

Lightshow

We wanted to see pretty displays of laser light. [Daniel Ross]’s Laser Oscilloscope 360 not only draws out pretty waveforms, but it does so in prime steampunk style. Both [Owen Trueblood]’s Laser Cyanotypes and [GRNCH]’s Scored: Laser Woodblock Prints flip the script, making beautiful images from lasers, but not the way we intended. Kudos.

DIY

We wanted to see what laser-involved projects you were building yourselves, from scratch. While we were shocked that we had no TEA laser entries, [Armin Bindzus]’s Versatile Laser Processing Machine more than made up for it. It’s a pulsed-laser do-everything machine that we’re absolutely jealous to see made real. And if you don’t think there’s some real laser DIY going on here, you’ve never maintained a q-switched diode pumped Nd:YAG laser.

With Remaining Eye

This was our catch-all category for doing basically anything else with lasers. It turns out that what you all mostly wanted to do was science. [Matt Venn] used a fast-rise-time laser driver to Measure the Speed of Light at Home, and got damn good results considering the 2 m baseline. [Tim] put together a 3D Printed Optical Cavity interferometer on a budget.

But it wasn’t all labcoats and pocket protectors. [WeldingRod1]’s Laser Bandsaw is basically as bad an idea as it sounds like it is. Please, please wear eye protection!