Forged documents could be signed off for good with a new technique that produces a 3D hologram of handwriting.
Graphologists use complex techniques to spot fakes
Through virtual reality and image processing, tiny pressure bumps in writing can be analysed to spot fakes.
Conventional techniques have involved using 2D analyses to examine the sequence of pen strokes.
The 3D method could be a "powerful tool" for forensic experts, said the physicists, whose findings are reported in an Institute of Physics journal.
Called 3D micro-profilometry, the technology could provide a solution for cracking down on will, cheque, and credit card counterfeiters, as well as the forgers of other important handwritten documents.
"We believe this type of 3D micro-profilometry is one of the most promising ways of detecting forged handwriting," said Professor Schirripa Spagnolo, head of the research team at UniversitÓ degli Studi Roma Tre in Rome, Italy.
No two signatures by one person are exactly the same in style, so the new technique involves making a 3D model of the pressure applied when a person writes.
The model translates the writing into an image showing dips and furrows of the sample so that anomalies can be detected.
Conventionally, handwriting has been analysed by forensic experts in 2D, looking at the sequence of pen strokes in handwriting, like a signature.
But this is not entirely accurate, because the exact sequence of strokes is not always clear and can vary.
"Using virtual reality and image processing, it is possible solve two of the most difficult problems in graphology: strokes superposing and strokes direction.
"These, in particular in case of same inks, are not detectable in a objective way with the traditional methods," Lorenzo Cozzella, part of the research team, told BBC News Online.
Bumps are usually made where one pen stroke crosses over another, and the new technique allows these to be seen.
"Finding these bumps allows experts to easily determine the sequence of strokes in a piece of handwriting and the tell tale signs of a forgery or original," said Professor Spagnolo.
"Another benefit of this technique is that it doesn't damage the sample."
This is particuarly important in forensic analysis because it means no physical or chemical processing has to be done to a document in question.
Counterfeiters usually try to forge signatures by tracing, but increasingly, they are using freehand methods to copy the characteristics of a signature.
By examining unique pressure and cross-over points with the 3D model, the researchers say forgers will be unable to copy an individual's signature easily.
"Graphology is a complex science," said Mr Cozzella.
"But this method, in one or two hours which is needed for a correct and precise scanning of a signature, allows a graphology expert to eliminate important doubts that changes definitely her or his final decision."
The Italian research was reported in the Institute of Physics' Journal of Optics A.