Since new automatic number plate recognition (ANPR) technology was fitted to police highway patrol cars in the Illawarra 12 months ago, up to six unregistered vehicles are being caught each day, attracting $530 fines.

ANPR is a mass surveillance method that uses optical character recognition to read vehicle registration plates.

Three infrared cameras fitted to the vehicle ensure that plates can be read day and night, taking images at a rate of six vehicles per second.

Wollongong highway patrol's Senior Constable Phil Roddy said the technology was an exceptional resource.

"It's a fantastic system; an added tool that highway patrol officers have," he said.

The system gives new meaning to the term "bells and whistles".

If an unregistered vehicle is detected, a bell rings. If warnings attached to the owner, such as previous offences and outstanding warrants are detected, a separate alarm is triggered.

Snr Const Roddy said that if the information checked out, the vehicle was pulled over, irrespective of how out of date the registration was.

"Even if it's one day out, we'll stop the vehicle. It's then up to the officer as to what action, if any, is taken," he said.

ANPR is not infallible; not all plates are picked up. But in seven hours on the road yesterday, Snr Const Roddy's vehicle detected 1843 plates, with five vehicles found to be unregistered, and another 18 to 20 with warnings attached.

ANPR is part of the NSW Police arsenal this Queen's Birthday weekend as part of Operation Stay Alert.

The annual campaign begins at 12.01am tomorrow and concludes at 11.59pm on Monday. Double demerit points will apply for all speeding, seat belt and motorcycle helmet offences.

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