Soon, camera with no lens

London: Scientists from US, have used materials that have properties purposefully designed rather than determined by their chemistry called metamaterials, to build an imaging system, which samples infra-red and microwave light.

The sensor also compresses the images that it captures in contrast to current compression systems, which squash images after they are taken. Most imaging systems, like those found in digital cameras, use a lens to focus a scene on a sensor studded with millions of tiny sensors. More sensors means more detail is captured and, usually, produces a higher resolution image. But the imaging system developed by graduate student John Hunt and colleagues at Duke University in North Carolina has no lens and instead combines a metamaterial mask or aperture and complicated mathematics to generate an image of a scene. The aperture is used to focus different wavelengths of light in different parts of a scene onto a detector. The different frequencies in the scene are then sampled sequentially. According to Hunt, this sampling helped to work out the distribution and mix of light wavelengths and their relative intensities found in a scene. Currently the imaging system could capture about 10 images per second, he said in addition the imaging system compressed the information as it was gathered. The Duke imaging system uses a thin strip of metamaterial, which ahs been mated with some electronics and processing software. Although it did not yet work with visible wavelengths of light, Hunt said that it could lead to a range of cheap, small, portable sensors that could find a role in many different fields. A research paper detailing the work has appeared in the journal Science. ANI