At SPIE Photonics West 2024 Conference, Merve Gocke presented on "Multimodal sub-terahertz fiber antenna for environmental and fiber deformation sensing," a project conducted with Eilam Smolinsky, Louis van der Elst, and collaborators at Cook Medical. Fiber sensors are widely utilized across various applications to detect signals related to environmental, physiological, optical, chemical, and biological factors. Thermally drawn fibers provide several advantages over other commercial options, such as improved sensitivity, accuracy, functionality, and ease of manufacturing. Multimaterial, multifunctional fiber sensors are particularly suitable for encapsulating critical internal structures within a microscale fiber, unlike macroscale sensors that rely on separate electronic components. The compact nature of fiber sensors facilitates the integration into existing systems, delivering the necessary functionality.
In this context, the paper introduces a multimodal, sub-THz fiber antenna that enables real-time monitoring of local fiber deformation and environmental changes caused by nearby objects. An electromagnetic wave generated by Time Domain Reflectometry (TDR) propagates through the fiber, allowing for precise spatial change detection along its length with exceptional resolution and sensitivity. Local impedance changes indicate fiber deformation, while alterations in the evanescent field surrounding the fiber signal proximity. The fiber antenna functions as a waveguide, where symmetric and antisymmetric modes are analyzed separately: the antisymmetric mode detects local deformation, while the symmetric mode captures environmental changes. This multifunctionality expands the applications of the fiber sensor from biomedical engineering to cyber-physical interfacing. In antisymmetric mode, the sub-THz fiber antenna can sense local variations in pressure, temperature, pH, and other physiological parameters. Additionally, the symmetric mode can be employed in touch screens, environmental security detection, cyber-physical interfacing, and human-robot interactions.
Reference
Merve Gokce, Eilam Smolinsky, Louis van der Elst, Jillian Noblet, Creasy Clauser Huntsman, and Alexander Gumennik "Multimodal sub-terahertz fiber antenna for environmental and fiber deformation sensing", Proc. SPIE 12835, Optical Fibers and Sensors for Medical Diagnostics, Treatment, and Environmental Applications XXIV, 128350I (12 March 2024); https://doi.org/10.1117/12.3000549