The BRAVO handheld Raman spectrometer (Bruker Optics) has been developed to generate background-free Raman spectra through the patented sequentially shifted excitation (SSE™). It is equipped with two temperature-controlled diode lasers (DuoLaser™, 785 and 852 nm), comprising Bragg-grating optical feedback. Both laser beams impinge on the sample sequentially in every measurement, and they are detected using different areas of the charge-coupled device (CCD), providing a 10–12 cm−1 spectral resolution. Data can be acquired from 170 to 2200 cm−1 and from 1200 to 3200 cm−1 exploiting, respectively, the 852 nm and the 785 nm lasers. The spot size is about 100 × 500 μm2 wide.
Raman bravo
Potential results
The BRAVO portable Raman output are four spectra: three spectrally shifted raw spectra generated by each of the two lasers from which the fourth processed Raman data is later extracted by the principal component analysis (PCA) software algorithm.