Speaker
Description
Terahertz (THz) technologies operating beyond 0.1 THz have emerged for a variety of applications, including motion sensing, security imaging, and high-speed wireless communications. Therefore, there has been a growing focus on electromagnetic field (EMF) safety within this frequency range. Since THz waves are absorbed at the tissue surface, localized heating occurs within a region of a few hundred micrometers. However, it is difficult to measure temperature rise induced by THz wave radiation using conventional optical fiber thermometers, because their spatial resolution is over 1 mm, which exceeds the size of the region where temperature rise occurs. In our previous research, we developed a biological-equivalent phantom incorporating temperature-sensitive fluorescent probes, which enables temperature measurement based on fluorescence intensity changes due to THz wave absorption. Using confocal laser microscopy, we successfully achieved three-dimensional temperature measurements with high spatial resolution of 5 μm in the XY plane and 20 μm in the Z direction. In this study, we constructed an experimental system by combining the Gyrotron which is a high-intensity THz wave source, with our temperature measurement system. We then investigated whether the internal temperature rise of a skin-equivalent phantom could be measured while it was simultaneously irradiated with 265 GHz waves.
