Speaker
Description
Diagnostic methods using near-infrared light (NIRS) are widely used due to their non-invasiveness and safety. However, traditional systems based on continuous-wave light face a fundamental limitation—strong scattering of light in biological tissues, which reduces their resolution and probing depth. This work aims to develop an experimental time-domain near-infrared spectroscopy system to overcome the limitations of classical NIRS and enable deep, non-invasive probing of biological tissues, particularly the brain. The proposed solution utilizes picosecond light pulses and single-photon detection with high temporal resolution. An inexpensive light source based on a laser diode driven by a signal generator was developed to create picosecond pulses at various wavelengths. The detection system is implemented using silicon photomultipliers (SiPMs), providing a temporal resolution of better than 50 ps. A cost effective TDC (Time-to-Digital Converter) chip with an accuracy of tens of picoseconds is used for high-precision time-of-flight measurement of photons. The developed hardware platform allows for the registration of the time-of-flight of individual photons, enabling the extraction of a signal that has passed through deep layers of diffuse media (e.g., through the skull). This paves the way for creating rapid diagnostic systems for cerebral circulatory disorders (including strokes) and for real-time monitoring of brain oxygenation during surgical operations. The results demonstrate the feasibility of building an effective time-resolved spectroscopy system using a combination of inexpensive laser diodes, SiPM detectors, and modern TDC chips. The presented development is a foundation for a new generation of non-invasive medical diagnostic complexes.
| Position | Junior Researcher |
|---|---|
| Affiliation | Joint Institute for Nuclear Research |
| Country | Russia |