Researchers at Georgia Tech have developed a prototype system to cancel out a digital camera trying to take a picture aimed its way. The system, described in more detail in this news.com article, targets any detected digital camera lens with focused light to thwart successful picture-taking. Where the photographer might have tried to capture a private meeting or an inappropriate picture, they instead will have a “blurry picture of what looks like a flashlight beam.”

The technology works by actively detecting a digital camera lens based on its ‘retroreflective’ properties. Digital camera lenses are much more retroreflective than other surfaces, such as eyeglasses. The system is constantly putting out infrared light to find any spying cameras; after sensing a camera lens aimed towards the system, it immediately targets the origin with a “localized beam of light” to neutralize the attempted photograph. The researchers provide more detail at their page describing the project.