High-resolution terahertz reflective imaging and image restoration.

We present a high-resolution terahertz (THz) reflective imaging system, operating at 2.52 THz, that employs a continuous-wave THz gas laser and a pyroelectric detector. The spatial resolution was evaluated from the system's modulation transfer function and tested by scanning a series of resolution targets. To further improve the image quality, Lucy-Richardson method was adopted to restore the scanning result. With the scanning spot profile measured using knife edge method, a satisfying restoration result can be obtained. Finally, the system's performance was observed by imaging some different test objects.