A 3D Printable Raman Probe

Scientific instruments are expensive. In a lot of cases, really expensive, so if you have spent any time in a well-equipped lab, the chances are that it would have been one backed up by the resources of a university, or a large company. Those experimenters who wish to pursue such matters outside those environments have traditionally had to rely on obsolete instruments from the surplus market. A fascinating endeavor in itself, but one that can sometimes limit the opportunity to pursue science.

It has been interesting then to see the impact of the arrival of affordable 3D printing on the creation of self-built scientific instruments. A fantastic example has come our way, [David H Haffner Sr]’s 3D printable Raman probe. A Raman spectroscope is an instrument in which the light scattered from the sample exposed to an incident monochromatic source is collected, as opposed to that reflected or transmitted through it. Scattered light can be a huge magnitude weaker than other modes, thus the design of a Raman probe is critical to its success. (If you are curious, read this multi-part explanation on Raman spectroscopy.)

This is a work in progress at the time of writing, but it still makes for an interesting examination of Raman probe design. Interestingly the sensor is a standard DSLR camera, which though not a cheap device is possibly more affordable than a more dedicated sensor.

This isn’t the first Raman spectrometer we’ve seen on these pages, we’ve also brought you a Fourier transform spectrometer, and plenty of more conventional instruments.

12 thoughts on “A 3D Printable Raman Probe

  1. “Those experimenters who wish to pursue such matters outside those environments have traditionally had to rely on obsolete instruments from the surplus market. ”

    Obsolete==nonfunctional?
    Obsolete==out of calibration?
    Obsolete==no longer obeys the scientific and engineering principles when it was the latest hotness?

  2. A friend bought an orchard and he wants to cheaply survey the soil for contamination.
    Any good hacks to do that? Meantime, he’s looking for a cheap older instrument.
    Thanks.

    1. Soil analysis also generally uses a solvent extraction step in advance of the FT-IR, GC-MS or whatever analytical method. Difficult to do meaningfully without the proper set-up. You can easily check pH and maybe salinity with simple instruments but anything beyond that is, indeed, best sent to a soil testing lab.

    2. Honestly GC-MS might be OK for some contaminants but is horrible to maintain and run (regular inert gas deliveries, expensive repairs if something breaks), and FTIR would be pretty awful (terrible specificity). Raman is very much suited to contamination detection (strong specificity), however it suffers from any fluorescent material in the sample (which is pretty common I imagine in a fruit orchard). Simple electrochemical tests are often the best for measuring specific contamination like heavy metals, or even better would be simple assay tests that you can buy for specific metals and contaminants.

      If he is mainly interested in heavy metals however, I suggest XRF which is extremely powerful, quick, and often portable.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s