Spectrometry
spectrometry

The Public Lab spectrometry project is an open source community effort to develop low-cost spectrometers for a range of purposes. All open spectrometry hardware and software efforts are welcome here! **Join in by:** * Learning [what spectrometry is](#Whats+spectrometry) * Reading about goals and [asking great questions](#Frequently+Asked+Questions) * Building a basic spectrometer using [one of our starter kits](#Starter+Kits) * Trying (and critiquing) our [community-made how-to guides](#Activities) and posting your own * Building on others’ work; hack and remix the kits to refine and expand them * [Share your upgrades](#Upgrades) for others to try -- and perhaps for inclusion in an upcoming starter kit release or add-on kit **** ## Starter Kits Public Lab’s Kits initiative offers several starter kits, including many of the basic components, and instructions for constructing a basic visible light spectrometer. The point of the kits is to provide a shared reference design for building experimental setups onto. Lego Spectrometer Kit Our most recent kit, incorporating community improvements while balancing low cost and ease of construction. Choose between webcam and Raspberry Pi camera versions and build attachments width standard Lego connectors. Build one Buy one Papercraft Spectrometry Intro Kit A $9 paper spectrometer which you can attach to a smartphone or webcam. It’s made of paper to reduce cost and complexity, and is mainly intended as an “introductory” or educational kit. The flat design can be printed on a laser printer or photocopied to make more. Build one Buy one **** ## Activities This is a list of community-generated guides for specific applications using your spectrometry setup (either a [starter kit](#Starter+Kits) or a [modded design](#Upgrades)). These [activities can be categorized](https://publiclab.org/wiki/activity-categories), and some may be more reproduced -- or reproducible -- than others. Try them out to build your skills, and help improve them by leaving comments. Together, we can repeat and refine the activities into experiments. > **Note:** If you are working on an **urgent issue** such as a threat to your or someone else’s health, please know that these techniques may not be ready for your use; it's possible that they never will be. [Read more here](/notes/gretchengehrke/09-29-2016/common-low-cost-technique-limitations) ### Activity grid [activities:spectrometry] **** ## Upgrades Have you added to your starter kit, improved it, or redesigned it? Show others how to take it to the next level by posting a build guide here: [upgrades:spectrometry] Add your upgrade guide here Request or propose an upgrade _Mods should include a parts list and a step-by-step construction guide with photo documentation. See an example._ **** ## Challenges We're working to refine and improve DIY spectrometry on a number of fronts; here, take a look at the leading challenges we're hoping to solve, and post your own. For now, we're using the Q&A feature, so just click "Ask a question" to post your own challenge. Be sure to add: * constraints: expense, complexity * goals: performance, use cases [questions:spectrometry-challenge] **** ## Builds There’s a lot going on in open source spectrometry -- if you’ve developed another open source design you’d like to show others how to construct, post it here! * [RamanPi](https://hackaday.io/project/1279-ramanpi-raman-spectrometer) * [Hackteria “drop”-style spectrometers](https://publiclab.org/notes/gaudi/04-03-2014/diy-micro-volume-spectrophotometer) / [DIY NanoDrop on Hackteria.org](http://hackteria.org/wiki/index.php/DIY_NanoDrop) * _Add yours here_ ##What's spectrometry? Colored light is often a blend of different colors. A spectrometer is a device which splits those colors apart, like a prism, and measures the strength of each color. A typical output of a spectrometer looks like this spectrum of the daytime sky, with the actual light spectrum at the top and the graph of wavelength (horizontal axis, in nanometers of wavelength) and intensity (vertical axis) below: [![sky.png](https://i.publiclab.org/system/images/photos/000/005/455/original/sky.png)](https://spectralworkbench.org/analyze/spectrum/19882) > Needed: overview of spectra, calibration, units, comparison, and fluorescence/absorption. Please edit this page or link to a resource, potentially [the Wikipedia page](https://en.wikipedia.org/wiki/Spectroscopy), although that's quite full of technical jargon. ## Software Spectral data can be analyzed with https://spectralworkbench.org to create spectra plots, find centers of emissions plots, and find similar spectra. Data also can be exported in various formats (JSON, CSV, XML) for further analysis and visualization. ## How does this compare to a lab instrument? The [Desktop Spectrometry Starter Kit](/wiki/desktop-spectrometry-kit-3-0) is only one part in an experimental setup, and the following shows where it fits in an overall diagram of a lab spectrometric setup: [![tmp_31873-IMG_20161027_101601_2-79757779.jpg](https://publiclab.org/system/images/photos/000/018/635/large/tmp_31873-IMG_20161027_101601_2-79757779.jpg)](https://publiclab.org/system/images/photos/000/018/635/original/tmp_31873-IMG_20161027_101601_2-79757779.jpg) [![tmp_31873-IMG_20161027_095939_2-108076392.jpg](https://publiclab.org/system/images/photos/000/018/636/large/tmp_31873-IMG_20161027_095939_2-108076392.jpg)](https://publiclab.org/system/images/photos/000/018/636/original/tmp_31873-IMG_20161027_095939_2-108076392.jpg) There are many, many different types of spectrometry and spectrometers -- many don’t even measure light. Even among those that do, some detect light in the ultraviolet range, and others in the infrared range of light. The range of Public Lab spectrometers depends on the range of the commercially available cameras we attach them to (~400-700 nanometer wavelengths). A commercially available product with a slightly wider range (from 335 to 1000 nanometers) is [available from Cole Parmer](http://www.coleparmer.com/Product/Cole_Parmer_Visible_spectrophotometer_335_to_1000_nm_wavelength_range_analog_output/UX-83055-10). **** ## Frequently Asked Questions [questions:spectrometry] Note our previous Frequently Asked Questions page, which [can be found here »](/wiki/spectrometer-faq) -- please help port these into the new system, here!...


Author Comment Last activity Moderation
cfastie "The Public Lab spectrometers rely on cameras to make images of diffraction patterns. So the raw data is a photograph or video frame. Processing the..." | Read more » over 7 years ago
jjoll "hello savargaz, thanks for the answer. what are your thoughts on distinguishing classes as large as all plastics. Will there be a unique spectral s..." | Read more » over 7 years ago
savargaz "You can most definitely use spectrometers to detect different types of materials. All materials are composed differently and thus will absorb and r..." | Read more » over 7 years ago
liz "This is amazing feedback!!! Thank you so much, i can't believe i just saw this now. " | Read more » over 7 years ago
xose "Cool!! Another interesting point to have in mind is the orientation of the slit in relation to that of the diffraction grating. More info here: htt..." | Read more » over 7 years ago
saeed957 "Thanks Xose, no I haven't tried but I will give it a try. " | Read more » over 7 years ago
xose "Hi @saeed957! Have you tried using a mobile phone? You can try taking the picture first and then upload it to the Spectralworkbench. I've modified..." | Read more » over 7 years ago
AvatarNikhil "Where can i get a PDF file to print those layout for the spectroscope ? " | Read more » over 7 years ago
warren "The Raspberry Pi mod would be very cool, especially as it presents opportunities to do un-corrected images (re: chris's above comments); several fo..." | Read more » over 7 years ago
cfastie "Hi Nicholas, That sounds like it was an exciting hour. If a live video connection to Spectral Workbench is an obstacle, it is always possible to ..." | Read more » over 7 years ago
warren "The Kits initiative hasn't disabled anything; the webcams are as shipped from the factory. There is some sparse guidance on this here, but if you k..." | Read more » over 7 years ago
warren "Thank you Pablo for investigating this! Very helpful. " | Read more » almost 8 years ago
pablo "The files at https://github.com/publiclab/spectrometer3/blob/master/spec3-pdf.zip when opened in inkscape gives the correct size. " | Read more » almost 8 years ago
pablo "Reviewing the original .svg files I see they have the size in pixels defined, not in inches or cm. So it makes the standard conversion. Before ver..." | Read more » almost 8 years ago
pablo "Mmmm, weird! The one I lasercut is 23.5cm long, as it should. I just measured it. However, all the files I am looking now in inkscape (the ones I ..." | Read more » almost 8 years ago
warren "Hmm, interesting -- but are you sure the one you made wasn't mini as well? The Ponoko one I cut ended up almost exactly 19 cm long when assembled. ..." | Read more » almost 8 years ago
pablo "Hey @warren, I made a test and it does fit in a 12x24 inches board. See my file: lasercut-spectrometer-3.0-12x24.svg Note, funny for my to talk i..." | Read more » almost 8 years ago
pablo "I had posted the .ai file I used to cut, and I've just uploaded the original .svg, as I am not able to open that .ai (check the research note https..." | Read more » almost 8 years ago
warren "Hi, @pablo - thought you might have thoughts on this, or maybe even design files to share? " | Read more » almost 8 years ago
rthalman "Ok, so here are the links to shapeways: Absorption Cell Body: https://www.shapeways.com/model/3dtools/5722864/0/123?key=0955c52c1c8596f6422b736ebda..." | Read more » almost 8 years ago
warren "Also see this one: https://publiclab.org/notes/briandegger/12-11-2015/silhouette-cut-public-lab-mobile-spectrometer-v2 -- though it's not too flesh..." | Read more » almost 8 years ago
warren "Wow, excellent! You can share a design on Shapeways by clicking "Edit product with this model" in the upper right: Then you can check "Offer for..." | Read more » almost 8 years ago
stef "@warren, @rthalman I will share the build details once I get some fotos. The public library operates on a cost recovery system so the cost of the p..." | Read more » almost 8 years ago
rthalman "@warren I have the .stl files in the description, you can upload those to Shapeways. In PLA on shapeways the absorption cell body costs $26; the Sp..." | Read more » almost 8 years ago