The anti-fraud devices will be incorporated in the 1.5 million certificates due to be sent out by exam board Edexcel. Features include a hologram that will not refract light if replicated, and an ink design that is invisible to the human eye but which can be checked with an ultraviolet lamp.

If the certificate is photocopied, a heat-sensitive spot vanishes and the word “copy” appears. A chemical compound prevents the type from being lifted off the certificate and altered.

A specialist secure printer that produces chequebooks for banks and tickets for Premiership football matches has developed the new-style certificate.

The print and design features mean it cannot be accurately reproduced by scanners, printers or photocopiers.

David Sands, head of Edexcel’s certification department, said: “We do not have a big problem with fraud but we have upgraded our certificate to keep ahead of the game. This is part of a wider strategy to introduce the latest technology into the exam system.”

The exam boards are in the middle of marking about 7.5 million scripts in time for results to be issued in August.

In May, Edexcel’s chief executive John Kerr said there were shortfalls of examiners in GCSE English, RE, history, information and communications technology and A-level economics and psychology.

However, John Milner, convenor of the Joint Council for General Qualifications, the exam boards’ umbrella body, said the boards were on target and insisted there was no indication of problems with examiner shortages.

A recent campaign to recruitvicars to mark papers produced a good response, which will boost RE examiner numbers for next year, he added.