The UK police department is testing a new generation of digital speed traps that could make it impossible for drivers to beat speed checks. Until now, most speed traps use radar to detect the speed of vehicles and a camera with a flash to identify those going too fast. But motorists could beat these traps simply by slowing down the moment they saw cameras or radar detectors. Developed by the Computer Recognition Systems of Cambridge, the new Speed Violation Detection Deterrent (SVDD) uses digital infrared cameras to photograph all cars passing fixed points such as overhead bridges. It also records the time cars pass and identifies them by using a software called optical character recognition that can read their licence plates. When a car passes another checkpoint, the system can calculate its average speed. The digital images are securely encrypted and automatically deleted if the average speed is within the limit ( New Scientist , Vol 164, No 2224).