Disease diagnostics of biological tissues using free-space technique in terahertz frequency range

The sensitivity of terahertz absorption to water, biological tissue structure content, and the degree of hydration of diseased tissues are exploited to distinguish between normal and malignant human skin tissues. This can be achieved using free-space technique in terahertz frequency range (110–170 GHz), with the reflection and transmission coefficients, which are converted into the dielectric constant.