Corrected emission spectra of carbon nanoparticles can provide excitation–emission matrices (EEMs) for a range of excitation wavelengths. Acquisitions take only minutes (λexc = 500–800 nm at 1-nm intervals, λem = 830–1350 nm at ~1 nm per pixel). EEMs are compiled by HORIBA Jobin Yvon’s Nanosizer® software. A double-convolution algorithm (U.S. pat. pending) in the software simultaneously computes excitation and emission wavelength coordinate lineshapes for each species within minutes; contributions from all spectral bands in a region of interest are found.