DAV 4 UV/VIS Spectrometer

I finally figured out how to calculate the quantum yield of my samples, so I used a known reference from the Oregon medical laser center (fluorescein in ethanol) and compared it to my new buffer solution of KBr (potassium bromide.)

Then I compared a sample of fluorescein I had done on May 3rd (fluorescein in ethanol) to the laser center's sample to get a more accurate quantum yield value.

http://publiclab.org/notes/dhaffnersr/05-07-2016/quantum-yield-calculations-for-fluorescein-in-potassium-bromide

I finally got to take some good readings from my oscilloscope program on the JDEPC-ov04 camera in my spectrometer, it doesn't work when the camera is running, but I can get good data on dB levels when it is at rest and on stand-by for data capture.

I did a low pass and a high pass scan:

This is the low pass scan in dB levels at rest.

I put together another test LED a Cree 470nm Blue LED (high power 3.7v IFM: 1000mA view angle 100%/without focusing lens.)

I mounted a 30 degree focusing lens like the one for the Prolight Uv LED, and tested it out today...What a whopper this one is!

Using the new spekwin32 v172.2P3 hardware control prototype software, I wanted to try it's capabilities out and do an analysis of a rhodamine b standard.

I think it turned out pretty good...

1. Further demonstrating the capabilities of my homemade spectrometer is a calibration curve done on 2 stroke motor oil:

Graph showing cfl plot blue band at 436nm and green band at 547nm

correction curve showing calibration quality fit of 3, target is always a fit of "0" but alas, soooo...far away!

After upgrading the DVD grating this weekend I naturally had to run a series of tests to recheck alignment and resolution, so this is a great demonstration of what a homemade spectrometer can do!

Fluorescein study 6 sample concentrations :

I updated the DVD grating this weekend and realigned it, so it is as straight as possible in relation to the slit and remains at a 45 degree angle. With the way it was, I was getting some mis-alignment from time to time, so I had to take care of that.