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Link to newly reorganized and uploaded general radiation detection, XRF etc. papers and references. https://www.qsl.net/k0ff/0_Nuclear_Physics_101_by_George_Dowell/ There may be broken links or other errors, let me know. If anything inappropriate or errors noticed please contact me. Geo

Since this seems to be the place to post information on Raman spectroscopy, I thought I'd post some of the things I've found so far as a sort of brain dump, in case it might be useful for others. Some of this info I originally posted on the XRF forum. [originally posted on XRF group:] In the meantime, here are a few things I've found: Typically Raman and cheap do not go together - much to my chagrin I got started by looking at this project: https://hackaday.io/project/1279-ramanpi-raman-spectrometer I have also followed this project quite a bit: https://hackaday.io/project/18126-dav5-v301-raman-spectrometer He has a blog that gives more detail, especially on his attempts to get a working CCD: https://tcd1304.wordpress.com I originally wanted to try to build the whole thing from scratch - then I got impatient and realized I was going to need a metal mill and/or drill press if I was going to fabricate everything including the kinematic mounts - so instead I decided to modify an existing microscope and hack together a makeshift spectrometer from Ocean Optics surplus parts Ocean Optics seem to be the Amptek of the UV-VIS-NIR world and their products are widely supported by 3rd party software, such as Spectagryph, which is appealing: https://www.effemm2.de/spectragryph/ Probably the best implementation out there is the Open Raman Project https://hackaday.com/2020/05/12/open-source-raman-spectrometer-is-cheaper-but-not-cheap/#more-411509 http://www.open-raman.org The key (read: expensive) parts are: Good dichroic mirror and band-block filter - There used to be an Ebay store that sold a ton of surplus filters (production overruns) from Omega Filters (https://www.ebay.com/usr/enciircleinc) but it looks like Omega was just acquired and the eBay store doesn't have the thousands of filters that were there just a few months ago Powerful, Monochromatic Laser - I use a lower end JDS Uniphase laser, but it's a bit weak. Their higher end Coherent Compass laser are more powerful with a more monochromatic beam - but not cheap Osram seems to be producing green LEDs that are single mode and display a very monochromatic beam and they are cheap. But, they typically come in at 510 or 520nm, whereas the traditional lasers were 532nm because they were frequency doubled 1064nm IR lasers. A lot of surplus optics out there are catered to the 532nm laser - e.g. 540nm cut off, which you wouldn't want for a 510nm laser The problems I have had are: properly launching the Raman output from the microscope into a fiber - I just got some fiber collimators that I'll experiment with too much noise in the spectrometer at long integration times - this means that I either need a more powerful laser or TEC cooling of the CCD sensor or both Thunder Optics is one of the cheaper turnkey solutions but they are still not cheap My favorite YouTube channel "Applied Science" did an episode on a quick down and dirty Raman system that shows cheap proof of concept: https://youtu.be/tRrOdKW06sk [A reply from Dud:] Soren, Thanks for the links The Open Raman is the best technical DIY one I’ve been following but he uses rather expensive open beam Thorlabs parts ($3,000) where I want to use fiber. http://www.thepulsar.be/article/openraman-starter-edition/ I have a B&W 473nm Raman laser and spectrometer but no software and for mineral work it’ll have a lot of fluorescence. I run Ocean Optics and Stellarnet spectrometers with both their factory software and Spectragryph for optical reflectance and LIBS and Spectragryph for XRF and gamma spec. I was planning on using one of those for the Raman but finding a single mode laser cheap enough is a problem not to mention the dichroic and edge filter. However it is in the bucket list. Dud