The Pulsar Engineering Community Board

I received my R spectrometer from Thunder Optics, and when I opened it up I found a nice B&W tek BTC-110S** .

This led me to some google searches where I found an old post from Luc on another forum:

• Open-source Raman spectrometer looking for academic partners

The same forum has some other good threads worth mentioning

• Laser-Diode based Raman Spectroscopy
• Cheap, Low-Resolution, Raman Spectroscopy

The last one has images of a design made out of legos that I found hilarious! Have amatures are gone too far??

There is still B&W tek units for sale, but I think I'm going to get a used ASEQ. I am thinking that the spectrometer part of Luc's design might be worth separating out into its own fiber-driven unit that could be used for a variety of uses. These B&W ones are running out and I don't think there is an open design one as easy to align. There is this one but someone in this community reached out and the maker of it says they ran into some problems with being able to align it.

** Okay what actually happened is I plugged in the wrong power adapter, a 12V instead of 5V for just a second, and now it no longer works. This led me to open it up and saw a scratched off label from the czerny-turner unit which was suspicious. A little while later I was looking on Ebay for cheap spectrometers and wow! Something that looks just like the inside for half the price. That's how I figured out what it really is. So I'm guessing thunder optics just buys these, fixes them up and sells them in a nice aluminum case.

They also look alot like the ScienceSurplus spectrometer that I tested a few years ago.

nb to save extra $$$ in your design, replace directly the rotation mount with the slit by a regular mount with the fiber connector -- the fiber core diameter will act as a slit (use a 20-50 microns core depending on the resolution you want).

That's how I use to do for straight spectrometers. The reason I'm using a slit in openraman is because imaging a spot on a slit is 1 dimension easier than imaging a spot on a tight fiber core/pinhole

Yes it is the same (link for anyone interested). Science Surplus has ran out though but they are still floating around ebay.

That's interesting point regarding the slit. Is a collimation lens needed after the fiber then or would the achromat doublet just focus the light straight from the fiber?

So it would just be fiber -> doublet -> diffraction -> camera objective -> camera

Yes that's correct -- you can see the bare fiber as a disk source with a cone whose half-angle is given by the NA of the fiber. So a lens in front of the fiber is sufficient to create a collimated beam.