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
jaksch "Switched the DVD-RW for DVD+R and tadaa works like a charm. So sorry for the kinda pointless topic, but maybe the info that DVD+RW does not work i..." | Read more » almost 6 years ago
jaksch "Update: I build a quick and dirty horizontal slit (approx 1mm wide) and indeed the image is more broad now. However, it is very dark. Below is a p..." | Read more » almost 6 years ago
warren "That's too bad - we can possibly start shipping keys with these if this affects everyone. A meter is pretty bad! We couldn't lengthen the case that..." | Read more » almost 6 years ago
lach_myers "OP Focus tests completed, with and without grating, and both show out-of-focus problems at all distances from about 80mm to over a meter - which is..." | Read more » almost 6 years ago
lach_myers "OP again. Mine is the standard (IR filtered) V2 camera, as I wasn't sure how the software would handle the non visible end. I've started investigat..." | Read more » almost 6 years ago
stoft "The spectrum of most common halogen lamps is neither smooth nor flat and generally do not have published spectral data. You might consider the Solu..." | Read more » almost 6 years ago
Ag8n "If you are trying a direct comparison ( apples to apples), see how the analytical lab is testing your samples. Probably, they will be using an adv..." | Read more » almost 6 years ago
tejadal1 "I bought one independently, though I do recommend that you offer that option. The stark contrast between the webcam's spectrum range and the NoIR R..." | Read more » almost 6 years ago
warren "We don't by default but probably should list that option as we do stock them. Can you email kits@publiclab.org to place an order? " | Read more » almost 6 years ago
tejadal1 "Hello! Nice work on the raspberry pi version of the spectrometer! A question, for @Warren , does PublicLabs provide the NoIR version of the Camera..." | Read more » almost 6 years ago
warren "So, you'll need to subtract a "clear" sample as a baseline -- there is some documentation at #absorption -- hope that helps! " | Read more » almost 6 years ago
Ag8n "A couple of gottchas here. I think you want to use the lego spectrometer with a light source. The light source would be fed through a cuvette fil..." | Read more » almost 6 years ago
Aleksi12358 "What contaminants exactly you are talking about? There is photometer reagents for many different chemicals. For example this shop has many differen..." | Read more » almost 6 years ago
Pushpaw "Just tried it and it is important to note that what you will see is 3 dots once the laser beam has passed through the diffraction grating. One is w..." | Read more » almost 6 years ago
Tomas0413 "The grating orientation might be the thing. I somehow didn't think about it before. I do have a laser pointer, and when I tried a few weeks ago, I ..." | Read more » almost 6 years ago
Pushpaw "As far as I can see that camera placement looks as it should. Going off on something of a tangent, do you happen to have a laser pointer. If you po..." | Read more » almost 6 years ago
Tomas0413 "Thanks for prompt replies. I'm travelling now without access to the spectrometer, I'll share new photos on Mon/Tue next week. " | Read more » almost 6 years ago
warren "I would try with the DVD first just because it's easier to know when it's properly aligned. Then upon confirming nothing else is wrong, and it's wo..." | Read more » almost 6 years ago
warren "OK - that's OK, the camera should be looking at the dark inside surface of the lid. The grating or DVD should bend/refract the light downward into ..." | Read more » almost 6 years ago
Tomas0413 "Warren, for now, I just completely removed the grating. And actually, I no longer use a slice of DVD, I bought a set of gratings (an upgrade). When..." | Read more » almost 6 years ago
Tomas0413 " " | Read more » almost 6 years ago
Tomas0413 "Pushpaw, thanks for the reply. Not sure why you mention auto-focus, you don't want it, and I'm pretty sure the camera that ships with the spectro..." | Read more » almost 6 years ago
warren "I think you can use a very fine pair of tweezers to slightly rotate the Pi Camera lens for a focus change. Do post if that works for you! But yes, ..." | Read more » almost 6 years ago
warren "This is the best. Thanks for posting, and great documentation!!! :tada: :grinning: :+1: " | Read more » almost 6 years ago