Researchers at Philipps-Universität Marburg in Germany made a material that turns invisible near-infrared laser light into broadband white light. It is built from tin and sulfur atoms in a diamond-like cluster, coated with organic groups. When a cheap, low-power infrared laser diode shines on it, nonlinear optical processes re-emit the energy as visible light. The light has a warm colour like a 2900 K tungsten-halogen lamp but keeps the narrow direction of the laser beam. The work was published in Science in 2016.
via It's not an illusion: Transforming infrared into visible light | ScienceDaily