A spectroscopy system that includes a light source that generates light having a plurality of wavelengths, a light transmitter that transmits the light to a target analyte, a light receiver that receives Raman-scattered light scattered from the target analyte, and a multi-wavelength spectroscopy assembly that acquires a spectrum by splitting the Raman-scattered light transmitted from the light receiver. The multi-wavelength spectroscopy assembly includes a single diffraction grating configured to diffract the Raman-scattered light and a single concave mirror configured to focus the Raman-scattered light.