Terahertz spectroscopy of intrinsic biomarkers for non-melanoma skin cancer

Continuous wave terahertz imaging has the potential to offer a safe, non-invasive medical imaging modality for detecting different types of human cancers. The aim of this study was to identify intrinsic biomarkers for non-melanoma skin cancer and their absorption frequencies. Knowledge of these frequencies is a prerequisite for the optimal development of a continuous wave terahertz imaging system for detecting different types of skin cancers. The absorption characteristics of skin constituents were studied between 20 and 100 cm^-1 (0.6 THz - 3 THz). Terahertz radiation is highly absorbed by water. Thus, the high water content of human tissue necessitates a reflection based imaging modality. To demonstrate a reflection based, high resolution, terahertz imaging system, a prototype imaging system was constructed at 1.56 THz. The system resolution was determined to be 0.5 mm and the system signal to noise ratio was found to be 70 dB. Data from the terahertz spectroscopy experiments and reflection based terahertz images at 1.56 THz are presented.