Raman Imaging: Defining the Spatial Resolution of the Technology

Raman images constructed from hyperspectral cubes recorded under well-defined confocal conditions show high-quality chemical contrast. Careful studies are required to determine the optimum measurement conditions and limiting spatial resolution of the technique. Calculations and measurements of the laser spot size for the high numerical aperture (n.a.) objectives indicate that spatial resolution of a wavelength (< 0.5 mm) is achievable under good conditions. What does that mean in terms of the quality of a Raman image?