New research by the University of Kent has found that optical coherence tomography (OCT) imaging technology can be used to distinguish between legitimate and counterfeit travel documents. It performs quantitative, non-destructive, high-resolution, sub-surface analysis of multi-layered documents, with a high imaging throughput and high-density volume. The technology typically takes less than 10 seconds to detect counterfeits.

Researchers assessed the security features in specimen passports and national ID cards, used OCT technology to expose the documentation’s translucent structures, and non-destructively enabled quantitative visualization of embedded security features.

The large number of fraudulent identity documents in circulation continues to be a concern for the U.K. Government, with passport fraud considered a severe threat to global security. While an increasing number of security features have been introduced by authorities in the latest generation of identification documents (such as several layers of polycarbonate), this sophistication can make the ability to distinguish legitimate from counterfeit documents an ever-evolving challenge.

“As documents become harder to forge, so does the sophistication of forgery detection. Although more secure than their predecessors, the latest generation of identity documents manufactured using polycarbonate layers remain susceptible to counterfeiting,” said Robert Green in the Forensic Group in the university’s School of Physical Sciences. “Fraudsters tend to adopt tactics such as copying paper or polycarbonate, reproducing documents and hologram images using sophisticated computer technology before re-laminating. Any of these tactics will affect the inner structure of a document, showing the importance of its sub-surface characterization and the benefit that OCT can provide to identify such tampering.”