High Quality Raman Data for Non-Homogeneous Samples using Raster Orbital Scanning

from a single spot on the sample surface. Depending on the homogeneity of the sample, the small spot size sampled with the tightly focused laser beam may miss the target material completely. A larger laser beam and sampling aperture can be used to acquire data from a larger spot on the sample surface, but as the aperture size is increased, resolution decreases and the high spectral resolution needed for spectral matching cannot be achieved. ROS sampling overcomes this trade-off between aperture size and resolution by quickly rastering a tightly focused laser beam over a large sample area. This preserves the high resolution of the tightly focused, laser spot used for traditional Raman sampling while improving sensitivity by acquiring data over a larger sample area.