Fingerprint scanners may seem the ultimate in identification technology, but tricking them is actually not all that hard. Now, scanning the pattern of veins on the back of the hand promises a more reliable system.

Vein recognition is already used in South Korea and Japan to control access to secure rooms in hospitals, factories, and office buildings. System manufacturers say each person has a unique vein pattern, which can be captured by infrared cameras. The technology has been more widely accepted than fingerprinting in Asia mainly for cultural reasons, says Michelle Shen of ePolymath Consulting in Toronto. "In Japan, they are very concerned about hygiene. They're reluctant with fingerprinting because they have to touch the sensor." With vein recognition, users merely hold their hands up to a scanner.