Computers learn to see and smell us

CHARLES ARTHUR

Science Correspondent

Computers that recognise our signatures, voices, fingerprints or hand- shape could soon replace humans to check credit cards, immigration permits and benefit payments, say experts in the field of biometrics.

The Department of Employment is at present studying the results of the biggest trial of its kind in the world, where people at unemployment benefit offices in Liverpool and Tyneside had to sign on an electronic "tablet" to verify their identity. This was then checked against earlier signatures.

In 15 months, the system checked 200,000 signatures from 20,000 people, and wrongly rejected just 0.1 per cent of applicants. Though a good forger can copy the shape of a signature, even the best cannot copy the acceleration and pressure of the original signatory.

Now the department may roll the system out to hundreds of offices across Britain. "It seems to have worked well in Liverpool," said Andrew Lewcock, head of the neural computing unit at AEA Technology, which developed the signature verification system. "Now they are looking at whether it's cost- effective." Such systems typically cost about pounds 200 per unit, with each office needing about six. The department had no comment on when it might widen the use of the system.

The finance company Visa International will also be using the new technology. Next year Visa plans to introduce a new generation of "smart" credit cards with an on-board microchip which can store an encoded signature, voice or fingerprint, making automatic verification possible. A Visa spokesman, Andrew Bapti, said that Visa had yet to decide which biometric to use.

Biometric systems can be programmed to identify any unique physical characteristic. Among those already in use are recognition systems for voice, signature, and the pattern of blood vessels in the retina at the back of the eye.

Emma Newham, editor of Biometric Technology Today magazine, said: "Everybody has been saying for the past 10 years that biometric systems would be in wide use in the next two years. It hasn't happened so far because the computing power hasn't been there. But once you have smart cards in widespread use, they will become commonplace. That should mean by the end of the decade."

Most biometric systems rely on powerful computers with "neural networks" - software that can pick out an essential pattern from a jumble of data.

Mr Lewcock said, "It's only become possible in the past five years to buy computers that are powerful enough to do this work for a reasonable price. In 1990 such power might have been just a dream, [but] today I can have a PC with more than enough power on my desk."

A British company announced earlier this week that it is developing a system which can distinguish people by smell. However, that will tend to be expensive - and so only useful to organisations requiring high security.

The US Immigration and Naturalisation Service has for some years been using a system which measures the ratios of finger lengths and handspan, for people who have previously been granted entry into the US without a visa.

The applicant puts their hand into a box, where a light system measures the ratio of finger lengths to the handspan. This is then recorded on the magnetic strip of a plastic card.

The amount of data needed is so small - just nine bytes - that it could be included in the machine-readable section of the new EU passport.