New rubidium detector makes infrared light visible

Infrared light detectors are vital for capturing images in the dark for everything from research to military engagements, but the most common infrared cameras are inefficient and require a large and expensive cooling apparatus to produce good results. But researchers at the University of Science and Technology in Hefei, China say they have found a way to make infrared light visible without high-powered lasers or other relatively complicated setups. Instead, the team passes two diode lasers through a container of rubidium vapor, exciting the rubidium atoms. When infrared light hits the rubidium, the atoms then emit a visible red light that can be picked up with lenses and turned into a digital image.

Like other non-cooled infrared cameras, this rubidium-based detector doesn’t deliver particularly high resolution. However, as seen in the picture above, it’s able to pick out images with reasonable accuracy. The top row is the direct image as it’s transferred (before passing through the rubidium), the middle is the image after passing through the rubidium, and the bottom is the “upconverted” image turned into visible light. Research on the new sensor was submitted for publication earlier this week.