By Jo Twist
BBC News Online technology and science staff
Airport security staff could get extra hi-tech help in spotting suspicious luggage with new X-ray displays that can switch from 2D to 3D in an instant.
The display is intended to bring 2D objects to life in 3D
The displays by Sharp Labs mean staff can see realistic 3D images from X-rays without wearing cumbersome glasses.
3D displays have already been used in the likes of laptops, medical X-rays and mobiles, but being able to switch would be a first for airport X-rays.
It is one of four finalists for the eminent MacRobert engineering award.
The prize is given out by the UK's Royal Academy of Engineering for technological and engineering innovation, on 10 June.
"The 3D technology we have developed aims at mimicking how people see 3D using natural vision," Dr Grant Bourhill, from Sharp's optical imaging labs, told BBC News Online.
"We try to send one image to one eye and a slightly different one to the second eye. We achieve that by using the 'parallax barrier' technique.
"The barrier is placed either behind or in front of a conventional crystal display which shows how the image is displayed to the viewer's eyes."
The parallax barrier has been known about for many years, but Sharp's key innovation was finding out how to turn off the barrier, or the 3D effect, to leave a perfect 2D display.
The barrier works with polarisation optics and a simple electronic switch can be operated manually or by software, says Dr Bourhill.
"The right and left eye image is interlaced on the display screen. The function of the parallax barrier is to separate those images to two separate locations on the screen.
"The right eye will see the right eye image and the left eye will see the left eye image so your brain will perceive 3D just like normal vision."
Already developed for mobile phones and laptops since last year, the displays will bring major benefits to airport security staff.
Conventional security X-ray systems, increasingly important in airport security in light of current terrorism concerns, use flat 2D displays. To view in 3D, they need to wear special eyewear.
Looking at objects in 2D makes it difficult to judge what is being viewed. With 3D technology, an object's depth and height is seen more clearly so staff can make better decisions about it.
With easily switchable displays, the likelihood of false alarms is reduced, explains Dr Bourhill, detection rates are improved, as well as the speed and efficiency of luggage screening.
Normal X-ray machines make objects appear "flat"
Being able to switch from 2D to 3D electronically does away with the need for the bulky and expensive goggles.
"A key part of the process was that our engineers from Oxford spent nine months in Japan actually transferring the technology developed in the UK to a state that was appropriate for mass manufacturing in Japan," said Dr Bourhill.
"We are delighted to have been selected as one of the four finalists of one of the most prestigious engineering awards."
Sharp is currently in discussions with a UK-based company to put the switchable displays into use at airports.
Although 3D displays have useful applications in games, photography, medical imaging, security and computer-aided design, the need to have a choice of swapping between 2D or 3D is a bonus, says Dr Bourhill.
The other finalists for the MacRobert award include self-cleaning glass, an eco-friendly fuel-injection system, and software that connects multiple system computer platforms.
The winner of the £50,000 prize money will be announced on Thursday and the prize will be awarded by HRH the Duke of Edinburgh.