A spectroscopy system includes a light source having an input light source, including semiconductor diodes generating an input beam with a wavelength shorter than 2.5 microns. Cladding-pumped fiber amplifiers receive the input beam and form an amplified optical beam having a spectral width. A nonlinear element broadens the spectral width of the amplified optical beam to 100 nm or more through a nonlinear effect forming an output beam that is pulsed. A filter is coupled to at least one of a lens and a mirror that receives the output beam and delivers the filtered output beam to a sample. A detection system includes detectors configured to receive the output beam reflected or transmitted from the sample. The detection system is configured to use a lock-in technique with the pulsed output beam and the spectroscopy system is adapted to detect chemicals in the sample.