The Quantitative Assessment of Small Structure Imaging Ability byTerahertz Wave

摘要

In this paper, the imaging ability of terahertz wave in time-domain spectroscopy (THz-TDS) imaging system is assessedby using the step-by-step scan imaging method to four small structures: thread, dots, round hole, and square on the focusof the imaging system. We utilize THz-TDS energy imaging model to acquire the energy distribution of terahertz wavepassing through the different small structure, which can be use as a criterion of imaging ability. Theoretically, terahertzimaging technology possesses highly spatial resolution because the size of spot is inversely proportional to thefrequency. Our experimental results also show that THz-TDS technology has a preferable spatial resolution on themillimeter scale. In addition, a more delicate and smooth image can be obtained by means of the nearest neighborinterpolation algorithm. A method to measure the size of target is provided. These results are important references for thefurther terahertz spectroscopy imaging research.