Chinese researchers have unveiled a groundbreaking laser system capable of discerning minute text and details from an impressive distance of 1.36 kilometers. This innovative technology, detailed in a study published in Physical Review Letters, marks a significant leap in resolution compared to conventional optical imaging.
The team from the University of Science and Technology of China employed a technique called active intensity interferometry. This method focuses on the interaction of light with a surface, rather than the object's appearance. The system emits eight infrared laser beams, and two telescopes capture the intensity of the reflected light to reconstruct an image.
"Through outdoor experiments, we have successfully imaged millimetre-scale targets located at 1.36 km away," the study authors stated. They achieved a resolution enhancement by about 14 times over the diffraction limit of a single telescope. The system can accurately read letters at a resolution of 3 millimeters, smaller than the width of a standard pencil.
While the system requires a direct line of sight and active laser illumination, limiting its use in covert operations, its potential is vast. Researchers are working to enhance laser control and integrate artificial intelligence (AI) for more accurate image reconstruction. This technology holds promise for high-resolution imaging and optical sensing applications.