This spectrometer is made with a black card inserts inside a 1" PVC or aluminum conduit box, and uses an HD USB webcam. This allows the user to view the spectrum in real-time, rather than taking a photo and analyzing it later. See a full bill of materials here:

• List of materials (currently somewhat messy)
• Most recent assembly pics

This hardware design is released under the CERN Open Hardware License 1.1.

Specs

(these are approximated but we should soon post a page with calibration information)

• around 400-900nm, maybe wider
• 5-10nm spectral resolution
• 20-30 samples per second
• around $20 in materials, drops to around $10 if you use a really cheap webcam
• approx. 1 hour construction time
• web-based, open-source capture/analysis software at: https://spectralworkbench.org

Goals

Our early goals are to:

• Identify a contaminant in a sample, like Polycyclic Aromatic Hydrocarbons -- like naphthalene, anthracene and tetracene. Tetracene has absorption bands well into the visible range.
• Identify a plant species by its spectrum. (see this helpful paper by Zomer et al) Or perhaps a mineral, using the ASTER spectral library
• Try to identify something in a smokestack plume, like a refinery plume

How to build your own

Instructions on building your spectrometer can be found here:

Video Spectrometer Construction »