Figure 17 – Layout of second experiment with two spectrograph channels.
Second Experiment: After I had the Ocean Optics PC1000 NIR spectrometer working, I obtained two PC2000 spectrometers that can read from 300nm to 1000nm. In the previous section I was using one PC1000 with an integration time of two seconds. In this section I am using the two PC2000 spectrometers with the integration time set to 250ms. Quite a bit of improvement compared to the first generation of pc spectrographs.
In Figure #17, the light is being injected via a fiber optic cable at -45 degrees and then I have two fiber optic probes taking readings at 0 and 45 degrees normal to the cell. The light entrance and exit orifices, of a piece of wood are spaced apart 6.33mm per the earlier calculations in Figure #9. The piece of wood is holding the fiber optic probes which is above ferrofluid cell with a large BK7 window resting on the jig.
Figure 18 – White LED Light source readings.
Figure 19 – Ferrofluid cell readings using the 45 degree incidence channel.
In this second experiment my light source is a twenty watt white LED pointed directly into the fiber optic cable and its spectrum readings are seen in Figure #18.
In Figure #19 I am showing the readings from the 45 degree incidence channel. The black line is ferrofluid cell without a applied field. The red line of graph is the ferrofluid cell with a red line of the ferrofluid cell aligned under the fiber optic probe. The yellow and brown line readings from the Ferrofluid cell are labeled and an example of the lines themselves is shown in Figure #20