The Public Lab Desktop Spectrometry Kit 3.0 is the latest version of the spectrometer. Read more about our Spectrometry program, the Oil Testing Kit it is is a part of, or the history of development. Previous versions 2 & 2.5 are here.

Parts List

• two-piece custom box and fold-up pieces printed on Neenah Sundance Eclipse Black Smooth 100 # paper. Download the latest print and cut files on github
• "gumstick" webcam (from a laptop screen) with USB cable. datasheet: Spec_of_JDEPC-OV04_Ver_1.01.pdf
• 45 degree wooden (pine or ash) block, 3cm x 3cm x 3cm
• Masonite bench 1/4" (6mm) x 40mm x 235mm
• 50cm of 3/4" (2cm) width adhesive-backed loop fastener (Velcro-style)
• 25cm of 3/4" (2cm) width adhesive-backed hook fastener (Velcro-style)
• DVD-R
• photo emulsion printed slit 0.2mm wide printed on .004" acetate. files on github
• 6 yard roll of 1/8" Thermoweb Supertape double sided tape. (3mm)
• printed assembly instructions (below)

Using your spectrometer

Once you've assembled your spectrometer and are ready to use it, plug it in and visit SpectralWorkbench.org to begin recording data with it. The web-based software works in the Chrome, Firefox and Opera browsers on most computers and Android phones.

(Peer) Support

Public Lab is not a corporation; we're an open community of DIY environmental science researchers which you have just joined! The best place to get help is the spectrometry mailing list; to join, sign up in the form to the left.

The spectrometry mailing list is made up of people like you, who are building and improving open source spectrometry techniques. Ask questions, look for help, and consider helping others too!

You can also post a question on this site; it helps to share some photos or screenshots of what you're trying to do:

Ask a question about spectrometry or Sign up to answer questions on this topic

Resources

• Common hardware issues
• Using the software (including setup and software troubleshooting)

• Frequently asked questions

• Background about the project

• peer-contributed research on open source spectrometry

Assembly

We're going to assemble the box, the bench that goes inside, the block the camera sits on, the angle that holds the grating in front of the camera, and the card that holds the slit in place.

In this photo, the bench is pulled out of the box and aligned with the slit card as it would be inside the box.

Assemble the box

step-by step video:

For the purposes of this instructional I've highlighted the edges of the box.

Place the box with the printing facing down. Pre-crease all the creases.
crease the box top as well.

Fold the left side of the box to the right, and insert the hold tab in place.

Fold the right side to the left and lay the box top on top so its tabs line up with the slots in the box bottom.

Insert the tabs together. The box top will not lay flat-- don't worry.

Pull the box top back to the right and fold the inner walls to the middle.

Hook the inner walls together.

Fold the outer walls up and over the inner walls. Use the two circular holes in the outer walls to position the inner walls while folding the outer wall over.

Flip the box upside down and make sure the tabs have all popped out of the bottom of the box. Walk your fingers along the inside of the box and make sure all the tabs are popped out of the bottom.

Assemble diffraction grating and angle

Pre-crease along all the folds.

Fold the bottom flap up and out of the way.

Fold the sides in.

fold the bottom flaps up so they are aligned and hold them in place with the hook fastener.

put a strip of double sided tape down on top of the bottom flaps.

fold the middle flap down over the bottom flaps and stick in place.

Splitting the DVD

try not to touch the surface of the DVD anywhere, hold pieces by their edges so as to avoid fingerprints. Slice a quarter of the DVD out.

using a fingernail or small blade, wedge the two layers of the DVD apart. disguard the aluminized side. If too much aluminum is on both sides, split another quarter of the DVD.

Slice a small rectangular piece out such that the rectangular edges are perpendicular to the edge of the DVD. This piece should be 1cm or so (half inch)wide.

Assemble the bench, block and camera

take the loop fastener (the fuzzy side) and cover the bench. it should take two strips next to each other length-wise.

Put two strips of tape on the underside of the camera.

Stick the camera down to the middle of the block's angled side. so that the bottom edge of the camera is flush with the edge of the block.

Put two strips of velcro on the underside of the block.

Design Notes

consult the following notes on development for the evolution of this design. @mathew (paper spectrometer 1)[/notes/mathew/11-07-2014/a-paper-spectrometer-design] @mathew (paper spectrometer 2)[/notes/mathew/12-06-2014/a-paper-spectrometer-design-pt-2]