The technology concerns planar optical antennas composed of thin metal films and dielectric materials for the efficient direction of the light emitted by light sources, such as fluorescent molecules and bio-markers. They consist of a reflector layer, adjacent to the substrate, and a director, semi-reflective, between which the emitter is positioned, integrated into a homogeneous dielectric layer. By respecting the rules for the distance between the layers and the emitter, it is possible to direct light in the upper plane within small angles with great advantage for collection both with traditional and fiber optics. The technology is scalable so it adapts to signals in different spectral ranges from visible to TeraHertz and over a large surface. The antenna can be manufactured with different methods, simple and flexible, for the deposition of thin films. It finds direct application in in-vitro fluorescence diagnostics, sensors and bio-imaging techniques. It also allows the creation of brighter, directional and potentially cheaper light sources and more efficient and directional detectors, with great impact in the fields of information technology, automotive and quantum technologies.
The technology makes it possible to create high-efficiency optical antennas through a planar configuration, extremely advantageous in terms of costs, simplicity of manufacture, spectral flexibility and emitter positioning. The efficient direction of light in very small angles allows to collect and measure even very weak light signals, at the level of individual fluorescent molecules. The measurement can be performed with simple optical instruments, directly coupling the directed emission to an optical fiber without the aid of additional lenses and objectives, and with a single-mode fiber coupling efficiency that can exceed 50%. These advantages make the technology flexible, scalable and suitable for different types of applications for the optimization and simplification of light signal collection systems.
Italy, PCT, Europe