Spectrometry
question: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
amir129 "I have one more question. The experiment says to use the light setting 530nm: "Use the spectrophotometer to measure the Absorption and Transmittan..." | Read more » over 6 years ago
warren "I believe this is the 2016 full PDF we printed from -- i did a new layout more recently that was just for one size, but this is the full-sized shee..." | Read more » over 6 years ago
warren "We're going to start selling the Lego spectrometer with a raspberry pi camera too -- could be a good option: http://publiclab.org/lego " | Read more » over 6 years ago
stoft "Great! 1) I'd also suggest using stiff cardboard, Exacto knife, hot-melt glue (or fast-set 'yellow' wood glue 2) use double-stick for the DVD att..." | Read more » over 6 years ago
amir129 "Thank you! I'll try to make one and will post the progress. " | Read more » over 6 years ago
stoft "You could buy a webcam from Amazon, use a spare DVD some razor blades, black paper, double-stick tape and build one for about $50 (most of the expe..." | Read more » over 6 years ago
amir129 "Thank you very much for such details explanation. I never thought about getting the reference to compare with the result. That is a good idea. Sin..." | Read more » over 6 years ago
stoft "Without a "reference standard" the measurements will all be relative; not absolute (like ppm [parts per mission]). So, the relative concentration w..." | Read more » over 6 years ago
amir129 "Thanks for your reply. I am trying to measure the percent transmission of light as a measure of pigment concentration in the water. So if i captur..." | Read more » over 6 years ago
stoft "The posted graphs are, mostly, just individual experimental plots. Assuming 1) working spectrometer, 2) has been wavelength-calibrated using a CFL ..." | Read more » over 6 years ago
warren "Some good notes on this over the years: https://publiclab.org/notes/cfastie/1-21-2013/spectrometer-image-quality https://publiclab.org/notes/warr..." | Read more » over 6 years ago
warren "We currently sell this pack: https://publiclab.myshopify.com/collections/spectrometry/products/acetate-slit-bundle With 0.09mm, 0.12mm. 0.15mm, an..." | Read more » over 6 years ago
UHF "DVDs work better with smaller track separation and therefore greater diffraction. " | Read more » over 6 years ago
warren "Hi! There are a few posts exploring this question here: https://publiclab.org/questions/dsvilko/06-13-2017/any-way-to-improve-on-the-dvd-grating ..." | Read more » over 6 years ago
amirberAgain "There are two devices I'm familiar with which could be relevant to your question: Nima - uses detection strips for gluten https://nimasensor.com/ ..." | Read more » over 6 years ago
Ag8n "What do you think of the ones that are transparent on all four sides? That way the cuvettes can be used for trans, abs, flores, or turbidity. The..." | Read more » over 6 years ago
stef "One reason why the plab spectrometer is less sensitive in the infrared wavelength is the ir filter as part of the lens assembly. There are research..." | Read more » over 6 years ago
cfastie "The Public Lab desktop spectrometer is quite capable of making a spectral graph of sunlight reflected from grass. The curve will differ from the pr..." | Read more » over 6 years ago
Ag8n "Metals usually take instruments like atomic absorption (AA) or inductively coupled plasma (ICP). These instruments can NOT be done easily on the P..." | Read more » over 6 years ago
amirberAgain "Si-based cameras (as the ones used in smartphones) have a very low sensitivity over 950nm and virtually none over 1000nm, so it is very unlikely. I..." | Read more » over 6 years ago
Ag8n "It sounds like Warren answered the question. I can give some more background. Proteins contain nitrogen, which isn't present in many other milk c..." | Read more » over 6 years ago
stef "What I was alluding to is that with all of the filter attenuation, the cmos sensor was still overloaded. This can be seen in the spectra submitted..." | Read more » over 6 years ago
Ag8n "There are two approaches to this, the hardware and software. Sounds like you took care of the hardware end very well. Can you think of any softwa..." | Read more » over 6 years ago
warren "Hi, would this help? https://publiclab.org/notes/wagnerc4/02-05-2014/fat-percent-in-milk I think it's fat percent, not proteins, but it could be s..." | Read more » over 6 years ago