A comprehensive overview of diffuse correlation spectroscopy: Theoretical framework, recent advances in hardware,...

Area of Science:

• Biomedical Optics
• Physiological Measurement
• Optical Sensing Technologies

Background:

• Diffuse Correlation Spectroscopy (DCS) is crucial for microvascular hemodynamic assessment in deep tissues.
• Advancements in sensors, lasers, and deep learning are driving new DCS methodologies.
• The complexity of DCS theory and system options can be a barrier for new researchers.

Purpose of the Study:

• To provide a comprehensive review of Diffuse Correlation Spectroscopy (DCS) for newcomers.
• To elucidate DCS hardware architectures, theoretical models, and component choices.
• To discuss emerging applications and future directions in DCS research.

Main Methods:

• Review of continuous-wave, frequency-domain, and time-domain DCS hardware architectures.
• Summary of corresponding theoretical models and data analysis tools.
• Discussion of silicon single-photon avalanche diode (SPAD) sensors and their applications in DCS.

Main Results:

• Detailed overview of DCS system components including lasers, sensors, and correlators.
• Comparison of SPAD sensors with existing technologies for DCS applications.
• Exploration of deep learning integration for DCS data analysis.

Conclusions:

• This review simplifies the complex field of DCS, offering guidance for new researchers.
• Emerging technologies like SPAD sensors and deep learning show significant potential for advancing DCS.
• DCS holds promise for future applications in medical diagnosis and physiological monitoring.