Abstract
Laser-induced, frequency-scanned IR photothermal radiometry was used to investigate the thermophysical properties of the paper on which several genuine and counterfeit British (£10) and U.S. ($50, $100) currency bills were printed. The radiometric photothermal amplitudes and phases were further compared with a theoretical model, which yielded simultaneous quantitative measurements of the thermal diffusivities and conductivities of the bills. Both statistical and single-specimen results demonstrated the excellent thermophysical resolution of the technique with prospects for its use in the nonintrusive, on-line identification of counterfeit banknotes.
Original language | English |
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Pages (from-to) | 400-407 |
Number of pages | 8 |
Journal | Optical Engineering |
Volume | 36 |
Issue number | 2 |
Publication status | Published - Feb 1997 |
Keywords
- Banknotes
- Diagnostics
- Infrared
- Photoacoustic and photothermal science and engineering
- Photothermal
- Radiometry