The Center for Sensor Materials maintains a state-of-the-art micro Raman spectrograph consisting of a Kaiser Optical Systems HoloProbe Raman Spectrograph coupled to an Olympus BX-60 optical microscope.

Unlike older spectrograph designs, the HoloProbe uses transmissive (rather than reflective) holographic filters and gratings made by Kaiser Optical Systems, to obtain very high light throughput. This allows the spectrograph to be connected to the microscope through an optical fiber, rather than through free space optics. The use of a single mode fiber produces a diffraction limited laser spot ( < 2 µm) at the sample. By incorporating a motorized stage on the microscope, it is possible to visualize the chemical distribution in a sample.

An optical image and a "Raman Map" of two glass spheres in a polymer film. The spheres are ~40 µ in diameter and the spectra was taken at 20 µ intervals. The signal is an integrated polymer peak, so the spheres appear as "holes" in the raman image of the film.