Comparative Analysis of Bio-Medical Imaging at 3.7 Terahertz with a High Power Quantum Cascade Laser

The comparative analysis of two major factors, i.e., contrast and input terahertz beam power in constructing bio-medical images using a terahertz quantum cascade lasers at 3.7 THz is investigated here. Image contrast based on water/fat content ratios in different tissues, is studied and were able to demonstrate distinguished contrast based on fat/water contents from the freshly cut pieces from various different parts (i.e. liver, fat, muscle and tendon) of untreated tissue. Liver contains more fat cells than muscle or tendon tissues, therefore liver and fat exhibit similar transmission in this measurement. Muscle and tendon contain higher water content and very little fat, therefore, exhibits rather small transmission and in turn produces a very dark image. The absorption coefficients of four different tissues were obtained at frequency 3.7 THz from the intensity measurement of the transmitted power of THz radiation