Method for Sampling Terahertz Pulses in the Time-Domain Using Modulated Difference-Frequency in the Repetition Rates of Femtosecond Lasers

Background

Burn injuries pose a substantial public health challenge, leading to hundreds of thousands of emergency department visits annually and requiring precise classification of severity to guide appropriate treatment. Accurately defining the spatial extent of severe burns is particularly crucial for surgical planning. While terahertz (THz) imaging offers potential for biomedical analysis, many existing THz devices are not suitable for field deployment, often rely on slow mechanical scanning for image formation, and typically lack the spectroscopic capabilities essential for detailed tissue characterization, material parameter extraction, and sub-surface analysis. Even portable THz spectroscopy systems often require mechanical translation for comprehensive imaging, and those utilizing compressive sensing techniques are limited by a narrow field of view, hindering their practical utility in clinical settings.

Technology

Researchers at Stony Brook University have developed a handheld terahertz (THz) spectroscopy and 3D imaging device designed for noninvasive evaluation of burn injury severity and high-resolution tissue imaging. It integrates advanced optical imaging with an analytical framework that combines physics-based models, artificial intelligence, and physics-informed machine learning. The device is capable of imaging a 40x27 mm2 field-of-view with 2000 traces per second over a 100 picosecond Time-Domain- Spectroscopic (TDZ) imaging. This new scanner represents a significant leap towards translating the THz-TDS technology from the lab bench to the bedside for real-time clinical imaging applications.