A confocal microscope, operable to focus on any of a plurality of portions of a sample, is optically coupled to a light source and to a spectrograph module. When the confocal microscope focuses on a particular portion of the sample, the confocal microscope directs incident light from the light source to the particular portion and directs responsive light from the particular portion to the spectrograph module. The spectrograph module can be operated using a first diffraction grating having a first line density to obtain a Raman spectrum of the responsive light from the particular portion of the sample. The spectrograph module can also be operated using a second diffraction grating having a second line density that is less than the first line density to obtain a fluorescence or phosphorescence spectrum of the responsive light from the particular portion of the sample.
