Hyperspectral imaging of gel pen inks: an emerging tool in document analysis.
Hyperspectral imaging (HSI) is a useful technique in the examination of writing inks, including gel pen inks, which combines digital imaging with % reflectance spectroscopy. This facilitates the detection of subtle differences between chemically similar inks. This study analysed a variety of blue, red and black gel inks on white office paper using HSI. The potential of the technique for ink discrimination compared to other analytical methods of examination is highlighted. Discriminating powers of 1.00, 0.90 and 0.40 were achieved using HSI for red, blue and black gel inks respectively. The overall discriminating power of 0.76 for the technique combined with its non-destructive nature and minimal sampling requirements demonstrates promise for this type of application.
Centre for Forensic Science, WestCHEM, Department of Pure and Applied Chemistry, The University of Strathclyde, Royal College Building, 204 George Street, Glasgow G1 1XW, UK.
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Reed
Centre for Forensic Science, WestCHEM, Department of Pure and Applied Chemistry, The University of Strathclyde, Royal College Building, 204 George Street, Glasgow G1 1XW, UK.
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Savage
Foster and Freeman Ltd, Vale Business Park, Evesham, Worcestershire WR11 1TD, UK.
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D
Edwards
Centre for Forensic Science, WestCHEM, Department of Pure and Applied Chemistry, The University of Strathclyde, Royal College Building, 204 George Street, Glasgow G1 1XW, UK. Electronic address: n.nicdaeid@strath.ac.uk.
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Nic Daeid
Discrimination; Gel pen ink; Hyperspectral imaging