A futuristic eye scanner that can identify individuals by scanning the unique image of a person's iris is being launched at a secondary school canteen today.

Sunderland's Venerable Bede School is to use the new system, thought to be the first of its kind in Europe, to allow pupils to buy their school meals without using any cash.

The technology will secretly pick out poorer pupils who are entitled to free meals from those who have to pay, who will be charged in a separate account.

It is hoped that the cashless system will save less well-off students from embarrassment and lead to greater equality among classmates.

Head teacher Dr Ed Yeates said: ''We are determined to remove all barriers within our school to maximise each student's learning potential. This technology allows us to move one step closer to achieving our goal.''

The new system, which will also be used by the school's 900 pupils to take out library books, is being installed by Edinburgh-based CRB Solutions.

Using the new image system, pupils will be asked to look into a camera for a few seconds while a video image is taken and then cross-referenced to a school database.

Designers say the fact that the iris is the most mathematically distinct feature of the human body makes it the most accurate means of identification.

The iris itself is also stable throughout a person's life, approximately from the age of one, so its physical characteristics do not change with age.

While fingerprinting resulted in a 3 per cent inaccuracy rate, due to the effect of dirt and scars, that from the new system would be just 0.1 per cent. The installation of the equipment is part of the £14m development of the school, which is moving to a brand new building in September.