Motion-resistant three-wavelength spatial frequency domain imaging system with ambient light suppression using an...

Area of Science:

• Biophotonics
• Optical Imaging
• Medical Diagnostics

Background:

• Conventional spatial frequency domain imaging (SFDI) systems face limitations in motion resistance and ambient light suppression.
• Real-world imaging conditions often introduce artifacts that compromise data reliability.

Purpose of the Study:

• To develop and evaluate a motion-resistant, three-wavelength SFDI system with ambient light suppression.
• To mitigate motion artifacts and ambient light bias in SFDI measurements.

Main Methods:

• Utilized an 8-tap complementary metal-oxide semiconductor (CMOS) image sensor (CIS) for simultaneous multi-exposure image acquisition.
• Implemented the Hilbert transform to reduce projected patterns per wavelength.
• Employed ambient light subtraction and rapid exposure/projection for motion artifact suppression.

Main Results:

• The 8-tap CIS-based SFDI system achieved an acquisition rate of 9.4 frame sets per second.
• Demonstrated good agreement in diffuse reflectance maps with conventional SFDI for tissue phantoms.
• Successfully measured hemoglobin concentration and oxygen saturation in vivo during motion and ambient light, with reduced artifacts.

Conclusions:

• The developed 8-tap CIS-based SFDI system shows significant potential for motion-resistant, ambient light-suppressed optical imaging.
• This system enhances the reliability of SFDI for challenging, real-world applications.