SPAD-sensor-based near-infrared imaging and dynamic phantom system

We developed a time domain near infrared optical tomography (TD NIROT) system for tissue imaging. To facilitate its evaluation, we created a dynamic tissue-mimicking phantom platform characterized by fluctuating internal optical properties and arbitrary anomaly shapes. Using water-soluble materials, we 3D printed and embedded shapes within silicone mixtures, and created the corresponding internal hollow structure after curing and submerging the phantom in water. By introducing liquid solutions of varying dye concentrations, we controlled the optical properties of the internal shape over time. The phantom was measured with our TD NIROT system. The internal shape was accurately imaged and the local dynamic changes introduced by the pumping system was revealed. These results show a great potential of such phantom systems for applications in assessing various optical imaging systems.