Instrument response function acquisition in reflectance geometry for time-resolved diffuse optical measurements.

Area of Science:

• Biomedical Optics
• Diffuse Optical Spectroscopy
• Quantitative Photonic Measurements

Background:

• Accurate optical property measurements in time-domain diffuse optical spectroscopy (TD-DOS) require simultaneous acquisition of the time-of-flight distribution (DTOF) and the instrument response function (IRF).
• Traditional IRF acquisition is often complex, time-consuming, and requires direct access to injection and collection fibers, limiting its practical application.

Purpose of the Study:

• To develop and validate a novel, simplified IRF measurement scheme for TD-DOS.
• To enable accurate quantitative optical property estimation without direct fiber access.

Main Methods:

• Proposed a new IRF measurement scheme utilizing reflectance geometry from a corrugated reflective surface.
• Validated the method using homogeneous phantoms and compared results to the conventional IRF acquisition method.

Main Results:

• The proposed IRF measurement scheme achieved an error in optical property estimation below 10% compared to the standard method.
• Demonstrated the reliability and feasibility of the new approach for TD-DOS.

Conclusions:

• The novel IRF acquisition method offers a faster, more accurate, and less operator-dependent alternative for TD-DOS.
• This technique is suitable for calibration in laboratory and clinical settings, improving the efficiency and reliability of quantitative optical measurements.