Ultra-thin film turns smartphone cameras into infrared detectors

Scientists at Hasselt University and imec have created a groundbreaking, ultra-thin film capable of transforming invisible infrared light into visible green light. This innovation promises to make sophisticated infrared imaging accessible and affordable, potentially by integrating it with standard smartphone cameras.

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We have developed a new material that can convert infrared light into visible light. This way, you can make invisible things visible.

The technology holds significant promise for the agricultural sector, particularly for assessing fruit ripeness. Currently, this requires expensive, specialized infrared cameras, often costing tens of thousands of euros. Drones equipped with these cameras are used to measure crop ripeness and optimal harvest times, but the weight and energy demands of such equipment are substantial.

Professor Koen Vandewal of UHasselt explained that the film, composed of 38 ultrathin organic layers, about 100 times thinner than a human hair, lights up green when exposed to infrared light. "We have developed a new material that can convert infrared light into visible light. This way, you can make invisible things visible," he stated. Attaching this film to a regular phone camera, which only sees visible light, effectively turns it into an infrared camera.

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If you attach it to a regular phone camera, which only sees visible light, you immediately turn it into an infrared camera.

Beyond agriculture, the technology's efficiency is notable. It operates without an external battery or power source and requires up to 4,000 times less light than comparable technologies to produce a clear image. Researchers have already demonstrated its ability to reveal details invisible to the naked eye on a 20-euro banknote.

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Such a camera quickly costs 40,000 to 50,000 euros. Our film is a lot cheaper and a lot lighter.

However, farmers will need to wait before this technology can be deployed in orchards. Professor Vandewal cautioned that this is fundamental research, and the immediate next step is integrating the film into a simple smartphone camera. While contacts with the fruit sector are not yet established, the potential for cost-effective, lightweight infrared imaging is substantial.

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If you have to load a heavy camera onto a drone, it costs a lot of energy to keep that drone in the air. A camera from a mobile phone is many times lighter. We certainly see possibilities there.