If you have ever felt sorry for celebrities hounded by cameras as they go about their daily business – be that pumping gas or entering a flashy nightclub – you can rest easy. A group of researchers at Georgia Tech has designed what could become an effective celebrity protection device: an instrument that detects the presence of a digital camera’s lens and then shoots light directly at the camera when a photographer tries to take a picture.

The result? A blurry picture of a beam of light. Try selling that to Us Weekly.

The Georgia Tech team was initially inspired by the campus visit of a Hewlett Packard representative, who spoke about the company’s efforts to design cameras that can be turned off by remote control. Gregory Abowd, an associate professor, recalls that after the talk, the team members thought, There’s got to be a better way to do that, a way that doesn’t require the cooperation of the camera. The key was recognizing that most digital cameras contain a "retroreflective" surface behind the lens; when a light shines on this surface, it sends the light back to its source. The Georgia Tech lab prototype uses a modified video camera to detect the presence of the retroreflector and a projector to shoot out a targeted three-inch beam of light at the offending camera.

The current version is bulky and expensive, but the researchers say a more practical example could be ready for commercial sale within a year. They imagine their contraption installed in environments where cameras might not be welcome: locker rooms, for example, or trade shows. The Motion Picture Association of America has already expressed interest in mounting the technology in movie theaters to combat video pirating.

More here.