(Phys.org) Fraunhofer researchers in the project “QUILT—Quantum Methods for Advanced Imaging Solutions” are using the photons to develop quantum optical solutions for wavelength ranges that have thus far proven to be virtually inaccessible. These wavelengths provide us with valuable information beyond the light of the visible spectrum: Short-wave ultraviolet radiation, for example, can be used to make the tiniest structures in cells visible. Infrared radiation provides information about noxious gases in the air or the composition of plastics, and long-wave terahertz radiation can be used to precisely determine the thickness of coating and paint layers. There is thus great potential in the fields of biomedical diagnostics, material testing or process and environmental analytics. The only issue is that creating and detecting these light waves requires significantly more resources than those used in imaging techniques for visible ranges.
For four years, teams of researchers from six Fraunhofer Institutes have been working with external organizations, supported by an advisory board with representatives from industry and science, to find ways of using the entangled photon pairs in different measurement methods in imaging, spectroscopy and metrology—making the invisible visible. The underlying principle is that while one photon has a wavelength that can be captured on camera, the other is designed to interact with the object under examination in the invisible range.
The partners have done important pioneering work for scientific and technical development in this relatively new field. The project has resulted in the submission and granting of seven patents, high-profile scientific publications and demonstrators for quantum-based imaging, spectroscopy and optical tomography. The researchers intend to use these to continue exploring new unconventional fields of application for quantum-based methods together with industry partners. Innovative branches of industry, such as environmental technology and medical engineering, are of particular interest.