There is an amusing pair of pictures in the latest issue of the Technology Review.[1] In a short article about a new imaging technology using terahertz frequencies, the first shows a photograph of a fellow holding a newspaper under his arm, and the second shows an X-Ray-like image of the same man holding a large kitchen knife. The knife is concealed under the newspaper, of course. A terrorist wielding such a dreadful weapon must be detected and deterred at all costs. The amusing bit is elsewhere, though. The face of the fellow in the first picture is blocked out. It is quite obvious he is only demonstrating the new imaging technology, but he must have insisted that his identity be concealed nonetheless. You never know with the over-eager authorities, such as Homeland Security!

Footnote

1. Vol. 106, No. 5, June 2003, p. 23.