Sound and vision

A camera system that produces images using sound rather than light could create far more detailed pictures than conventional ultrasound equipment.

The acoustic device, developed by a team led by Dr Chris Stevens, a lecturer in engineering science at Oxford University, could be used in enhanced medical ultrasound and airport security scanning to provide images of hidden hard plastic and ceramic objects. The device can also produce clear pictures underwater and through smoke and fog.

Sound imaging is already used in medical ultrasound and underwater sonar systems. However, the resolution of images produced by current technology is limited by the amount of sound data that can be collected.

The Oxford device works like a digital camera, where data from an array of light-sensitive detectors is correlated on a CCD chip to build an image. But in the case of the Oxford device, data from a large array of microphones is used.