Mobile phones using advanced fingerprint security technology will be on sale in Europe this autumn, paving the way for biometric mobile ecommerce authentication.

Only users with their fingerprint registered to a handset will be able to unlock the keypad and make a call.

The technology overcomes security concerns about storing an optical fingerprint image on a phone by using a software algorithm to convert specific characteristics of registered prints into a mathematical template. Only the template is stored, not the print itself, and it cannot be converted back into an image.

'First of all the fingerprint system replaces the PIN number - the user just swipes their print and then they get through,' said Shaoyun Cheng, product marketing manager for Fujitsu Microelectronics, which has developed the sensor technology.

'It can also be used as a kind of joystick, if you swipe your finger in different directions, so it can be used for different types of games,' she said.

The technology is already on the market in Japan and is being used to authenticate ecommerce transactions made from the phone.

'Locks and games are just the first stage. If you are making ecommerce transactions using the mobile phone then the fingerprint sensor will become a lot more useful,' said Cheng.

'Access using a fingerprint gives you entry to a certain security area to make electronic payments,' she said.

The phones will use a 'sweep' sensor where the user swipes their finger across a very thin scanner rather than the larger touch sensor system.