Sep 28 2007
High resolution images taken by satellite or aircraft are great - but the field of view in such pictures is tiny. To monitor a large area, the images have to be tiled like pieces in a jigsaw puzzle before a full picture can be built up.
This can cause problems: vehicles can end up appearing more than once if they move from one image to the next between exposures, for example. Such errors creep into virtual globes like Google Earth and Microsoft Virtual Earth and online mapping tools.
So a group of researchers at Sony and the University of Alabama have come up with a wide-angle camera that can image a 10-kilometre-square area from an altitude of 7.5 kilometres with a resolution better than 50 centimetres per pixel.
The trick is to build an array of light sensitive chips that each record small parts of a larger image and place them at the focal plane of a large multiple-lens system. The camera would have gigapixel resolution, and able to record images at a rate of 4 frames per second.
The team suggests that such a camera mounted on an aircraft could provide images of a large city by itself. This would even allow individual vehicles to be monitored without any danger of losing them as they move from one ground level CCTV system to another.
The camera could have military applications too, says the team. Mounted on the underside of an unmanned aerial vehicle, the gigapixel camera could provide almost real-time surveillance images of large areas for troops on the ground.