Researchers at Northwestern University have created a high-resolution camera that can see the unseen. This innovative invention can see around corners, through skin and potentially the human skull. Called synthetic wavelength holography, the method works by scattering coherent light onto hidden objects. The light scatters again before returning to the camera. The scattered light signal is reconstructed by an algorithm to reveal the unseen objects.

Photographing images behind inclusions is called non-line-of-sight (NLoS). Northwestern has created such precision with this imaging, an image through the skin could show small capillaries, or a beating heart through a chest. A more in-depth study was published last month in the journal Nature Communications.

This research could play a large part in noninvasive medical imaging, finding health issues at more treatable phases. Navigation systems in vehicles and industrial machinery can be repaired in record time. The NLoS technology brings endless potential.

"Our technology will usher in a new wave of imaging capabilities," said Northwestern's Florian Willomitzer, author of the study. "Our current sensor prototypes use visible or infrared light, but the principle is universal and could be extended to other wavelengths. For example, the same method could be applied to radio waves for space exploration or underwater acoustic imaging. It can be applied to many areas, and we have only scratched the surface."

Changing the path of light

Light travels in straight lines. When a wall, bricks, cars or other opaque material comes into play, they become mirrors. Someone driving on a curving road could use this technology to prevent an accident; another vehicle or an animal on the roadway could be exposed with time to react. A patient needing an invasive procedure like a colonoscopy could also benefit from synthetic wavelength holography.

This technology is still in early prototype phasing, however within the next 10 years it could be a reality.

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