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All Over But the Funding: Open Hardware Spectrometer Kit

Posted by timothy on from the what-is-the-exact-color-of-your-van? dept.

New submitter mybluevan writes "The Public Laboratory for Open Technology and Science is putting together an open hardware spectrometer kit on Kickstarter. The kits are built using an HD webcam, discarded DVD, and a couple other odd bits. They've also put together a kit for your smart phone and open-source software for desktop, Android, and iOS. Need to analyze the contents of your coffee, the output of your new grow lights, or a distant star on a budget? Just build your own spectrometer, or pick up the limited edition steampunk version." Besides making cool hardware, they'd like to "build a Wikipedia-style library of open source spectra, and to refine and improve sample collection and analysis techniques. We imagine a kind of 'SHAZAM for materials' which can help to investigate chemical spills, diagnose crop diseases, identify contaminants in household products, and even analyze olive oil, coffee, and homebrew beer."

1 of 62 comments (clear)

  1. Lots of work has been done here by Anonymous Coward · · Score: 5, Informative

    Lots of people have been working in this field. The most impressive results are achieved by the astronomy community. link It is possible to produce a home made spectrometer that gets useful results. Some of these are capable of resolution sufficient to identify chemicals. These are sophisticated and often use a peltier cell to cool the CCD in order to reduce noise. link

    I did a project whose aim was to produce a cheap spectrometer to match paint colors. link The problems I found were:

    1. Cheap webcams are quite noisy
    2. Cheap webcams are not at all linear
    3. For dark colors, sensitivity is a big problem
    4. The spectrum of the light source varies depending on which angle you view it from.
    5. Organizing the data is perhaps the biggest problem of all

    My own engineering trade-off was sensitivity vs. resolution. To get spectra for dark colored paints, I widened the slit which reduced resolution. That, as far as I could tell, was reasonable because I wasn't trying to identify chemicals and the spectra from paints weren't particularly sharp.

    The folks in TFA have a site where people can upload spectra. That's fine but a huge database of spectra is not too useful. The spectra have to be organized somehow. Here's an example. In fact the problem can be quite daunting