A system for detecting stimulated emission from a material of interest comprising: an excitation source; and an imaging component; wherein, in use, the system is configured to: a) emit excitation radiation from the excitation source for a first time period, the excitation radiation having a wavelength suitable for inducing stimulated emission in the material of interest; b) capture a first image via the imaging component, the first image substantially consisting of a background illumination component and a stimulated emission component; c) stop emitting excitation radiation for a second time period; d) capture a second image via the imaging component, the second image substantially consisting of the background illumination component; e) create a difference image corresponding to the difference between the first and second images, such that the difference image includes any stimulated emission signals from the material of interest.