Examination of the Influence on Precision of the Wireless Temperature Measurement Induction Heating System by 37 °C Constant Temperature Environment

In this paper, we built a system capable of maintaining a constant temperature of 37 °C simulating internal body environment to adapt to clinical condition of hyperthermia. We then examined the effect of a constant temperature environment on temperature detection accuracy of wireless temperature measurement induction heating using Au-coated ferromagnetic implant with low Curie temperature (Au-FILCT) in vitro. We built an experimental system consisting of drive coil, pickup coils, reference coil, Au-FILCT sample holder, and water tank equipped with a constant temperature system. Using the constructed system, we measured the temporal change of superimposed voltage and temperature of Au-FILCT five times while adjusting the distance between the drive coil and the Au-FILCT at 1-6 cm every 1 cm. We confirmed that the temperature of Au-FILCT can be heated above the treatment temperature of 45 °C within 295 s and the S/N ratio of the superimposed voltage was 22.4 dB at a distance of 5 cm. The result shows that the detection accuracy of the developed system can be improved by stabilizing the change in temperature of Au-FILCT under the constant temperature environment of 37 °C. We also confirmed that this system can detect temperature at a distance of up to 5 cm.