Recent progress of terahertz imaging technology

A pulsed terahertz (10/sup 12/ Hz) or a "T-ray" occupies a large portion of the electromagnetic spectrum (0.1 THz to 10 THz) between the infrared and microwave bands. We expect that the research in the THz band in the 21st century will become one of the most promising research areas for transformational advances in physics and biology, as well as in other interdisciplinary fields.