Lego Spectrometer
lego-spectrometer

This is the latest version of Public Lab's DIY Desktop Spectrometry Kit -- the Lego Spectrometer. It addresses issues of rigidity, sourcing, modularity, and image quality over previous versions. We've been making and distributing [Do-It-Yourself spectrometers](/w//spectrometry) since 2011, and have been through [4 major kit versions](http://store.publiclab.org/collections/spectrometry) and hundreds of different community contributed modifications, new versions, changes, and more. ## Get a kit This is an open source kit, so you can just build your own -- but to **order parts for a kit**, visit the Public Lab Store: ## Design goals Over the years, we've identified a few really critical improvements that have been tough to solve: * rigidity * easy to source parts * modularity - working together * image quality Our mission is to make it **easier, cheaper, and more accessible to do environmental monitoring**, and to do that as an open source, collaborative community. And of course part of that is cost -- while people build upon our kits with more expensive options and upgrades, we want the basic kit to be extremely affordable. ## Quick start [notes:grid:lego-quickstart] ## Questions [questions:lego-spectrometer] ## Building your Lego Spectrometer [activities:lego-spectrometer] ## Spectrometry activities [activities:spectrometry-sampling] **** ## Spectrometer calibration [activities:spectrometry-calibration] **** [![tinkercad.png](https://publiclab.org/system/images/photos/000/022/935/large/tinkercad.png)](https://publiclab.org/system/images/photos/000/022/935/original/tinkercad.png) _Tinkercad model, below_ ## Parts ### 3D models * Tinkercad: https://tinkercad.com/things/43IqCTHE7Iz * Thingiverse: https://www.thingiverse.com/thing:2711528 ### 3D brick models Lots of great brick models are available here: https://printabrick.org/ and on http://thingiverse.com * assorted standard bricks: https://www.thingiverse.com/thing:2626413 * holey bricks: https://www.thingiverse.com/thing:1095326 * sloped brick: https://www.thingiverse.com/thing:527185 * corner L brick: https://printabrick.org/bricks/2357 * brick w/ peg: https://printabrick.org/bricks/2458 (I used this instead of a 1x2 hole brick + a friction peg, because I couldn't find a model for the brick) Brick dimensions are nicely described in this diagram from Wikipedia: https://commons.wikimedia.org/wiki/File:Lego_dimensions.svg Print files for the black cardstock insert can be [found here](https://publiclab.org/notes/abdul/10-19-2016/foldable-paper-spectrometer-instructions). ...


Author Comment Last activity Moderation
stoft " Right ... the optical distances are very small ;-) which is why mechanical rigidity is so important ... (think of the 'optical bench' which is mad..." | Read more » almost 5 years ago
jenjimah " ^^^ I just realized you were referring to line spacing in microns, not lines/cm! Now it makes sense. " | Read more » almost 5 years ago
jenjimah "Also - I like the idea of microscope slides, except that glass strongly absorbs UV <400nm. I'm not sure of how well the pi NoIR is on that range..." | Read more » almost 5 years ago
jenjimah "Yes, so far I'm trying to accomplish all those 3 points. As for the slit, I made it from a razor blade so it should fulfill the criteria. I compare..." | Read more » almost 5 years ago
stoft " A while back I experimented with some 35mm 'slide-mount' holographic grating film (I believe it was 1200) vs the DVD (which is 740). The diffracti..." | Read more » almost 5 years ago
jenjimah " Thanks for the feedback, and for the equation. That's super helpful. I asked the PublicLab when I ordered my kit regarding the diffraction lines/i..." | Read more » almost 5 years ago
stoft " Looks like a nice clean construction. The glue should help mechanical stability. I did notice the swap from DVD to what appears to be a film holog..." | Read more » almost 5 years ago
warren "Awesome! They're just standard 1cm x 1cm ones. They don't fit amazingly in LEGO so I'd love to figure out a 3d-printable holder! On Sun, May 12, 2..." | Read more » almost 5 years ago
joquendo " The underside of the Raspberry Pi " | Read more » almost 5 years ago
ali3585 " try this https://www.happy-schlank.de/ " | Read more » almost 5 years ago
joquendo "Here is the compartment. " | Read more » almost 5 years ago
joquendo " That is a fair point. Not sure why I didn't think of that. Thanks. I also made a few mods to my build. I extended the main housing to add a sm..." | Read more » almost 5 years ago
Bronwen " Hi @joquendo, we use 4.5mL Square Spectrophotometer Cuvettes, but if you're working with your own legos you can adjust to accommodate other sizes ..." | Read more » almost 5 years ago
warren "They're the same as the older paper spectrometer templates, yeah! But cut down a little more to fit nicely. You can find the outline to print here:..." | Read more » over 5 years ago
pdhixenbaugh "Hello, thanks for your question! Hopefully it gets an answer soon. :) " | Read more » over 5 years ago
warren "This is really great feedback, and excellent for others looking to assemble the kit. Great work, and thanks for sharing, Carl! On Thu, Oct 11, 201..." | Read more » over 5 years ago
warren "These are great questions!!! I think DVDs are consistent but have no evidence to support it. I do think they're close enough for your spacer idea t..." | Read more » over 5 years ago
carlcrott "More questions: 1) Are DVD diffraction angles consistent? Could a spacer be designed that would correctly orient the camera with precision + repea..." | Read more » over 5 years ago
aga "Are there any cut out templates for the card papers used in this design? " | Read more » over 5 years ago
happywheelsgame "http://happy-wheelsgames.com Hope that the site will be on top, to get more players and help people enjoy after the days tired. " | Read more » over 5 years ago
carlcrott "@warren I did a few things differently: I opened up the webcam + stripped it of its black plastic housing I left the DVD in the freezer overnigh..." | Read more » over 5 years ago
warren "Hi! Sorry u had trouble... We've found that some DVDs (even in the same batch) are much harder than others for reasons we don't understand. Did you..." | Read more » over 5 years ago
carlcrott "Prepping the DVD is a HUGE pain. Tried: Xacto knives Duct tape ( works but leaves residue ) Sticking it in the freezer Super glue doesn't work. T..." | Read more » over 5 years ago
warren "I think the best method I've seen is to actually assemble it and loosely attach the cover. Then see where the spectrum falls on the screen. You can..." | Read more » over 5 years ago