Applications of Various Sensors for Detecting THz Waves in Adverse Conditions

Abstract

Comparison of atmospheric transmission in the bands ranging from terahertz (THz) to infrared (IR) bands using MODTRAN and available literature data show that THz radiation is not dramatically attenuated in adverse conditions when compared to IR bands especially at long distances. Favorable THz bands and mechanisms for detection of low IR signature target under adverse conditions in these bands are determined. In this study, a set of experiments are conducted to compare THz detection mechanisms, which are THz detectors and IR microbolometer cameras. Typically, IR Microbolometer cameras are not sensitive enough to detect THz waves and their sensitivity needs to be improved. While THz microbolometer cameras are being continuously improved the use of a THz to IR converter intermediary component allows a cost-effective solution to the problem. A THz to IR converter based on a metasurface absorber is studied in this regard. The effectiveness of the device is simulated and the temperature difference that can be detected with the IR microbolometer camera is modeled based on heat transfer equations.