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Updated: Aug 5, 2026
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Fluorescence Imaging with One-nanometer Accuracy (FIONA)
Published on: September 26, 2014
Camera-free NIR-II fluorescence molecular tomography via single-pixel spatial frequency domain imaging with photon
Optics Letters
|July 31, 2026
Summary
This study introduces a novel camera-free approach for quantitative deep-tissue fluorescence molecular tomography (FMT) in the second near-infrared window (NIR-II). The new method achieves high sensitivity and resolution for deep tissue imaging, overcoming previous limitations.
Area of Science:
- Biomedical Imaging
- Optical Engineering
- Medical Physics
Background:
- Second near-infrared window (NIR-II) fluorescence molecular tomography (FMT) offers superior tissue penetration and contrast.
- Quantitative deep-tissue imaging is challenged by ill-posed problems from photon diffusion and limitations of short-wave infrared (SWIR) detectors.
Purpose of the Study:
- To develop a camera-free NIR-II FMT architecture for improved quantitative deep-tissue imaging.
- To overcome the cost, noise, and scalability issues associated with traditional SWIR focal-plane arrays.
Main Methods:
- Integration of NIR-I spatial-frequency-domain (SFD) structured illumination with NIR-II single-pixel photon-counting detection.
- Fusion of co-registered excitation-reference and fluorescence measurements using a multi-frequency normalized Born formulation.
- Reconstruction of the effective fluorescence-yield distribution.
Main Results:
- Demonstrated millimeter-scale dual-inclusion separability and sub-millimeter axial localization at depths up to 7 mm in phantom experiments.
- Achieved a near-linear response of fluorescence yield.
- Validated the hardware-efficient framework for high-sensitivity NIR-II fluorescence tomography.
Conclusions:
- The developed camera-free NIR-II FMT framework offers a scalable and hardware-efficient solution for quantitative deep-tissue imaging.
- This approach addresses key limitations of existing technologies, paving the way for enhanced sensitivity in fluorescence tomography.
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