Principal component analysis for the forensic discrimination of black inkjet inks based on the Vis-NIR fibre optics reflection spectra

- FORS spectra of inkjet prints were obtained in a complete nondestructive way.
- Portable Vis-NIR spectrometer, allowing evidence of alteration to be uncovered.
- PCA was able differentiate samples into the groups.
- Inkjet inks with carbon black were separated from the other.
- Validation proved the applicability of the method for differentiation of printer.