Digital cameras may soon get disabled via security systems that temporarily blind them.

The process exploits a property of the image sensors used by digital cameras - they are retroreflective, that means they are sending light back directly to its origin rather than scattering it as a normal mirror would do.

Researchers at the Georgia Institute of Technology developed a prototype that uses light beams and cameras to scan areas for retroreflective dots matching sensors in shape. It then flashes a beam directly at those sensors, overwhelming them. Future versions might use infrared lasers at low, safe energy levels instead of light beams.

The camera neutralizing technology could thwart clandesting photography or tackle the $3-billion-a-year problem of movie piracy. It would prove ineffective against conventional film cameras however, or single-lense reflex cameras, which after all use folding mirrors to mask their sensors except when a photograph is actually taken.

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Author of the original article is Charles Q. Choi at Scientific American. The article was published in the September 2006 issue of Scientific American.