In this project we study exposure techniques and the necessary components and subsystems for active imaging in the spectrum of the W-band (75-110 GHz). It is a hitherto unexplored area of ??the electromagnetic spectrum in general and for imaging in particular, as this domain has yet to reach its full technological expansion. This spectral region is unique in that it has both sufficient resolution and sufficient penetration depth through many materials to detect and visualize a wide range of hidden objects (eg worn by people under their clothing). Since the reflection coefficient of human tissue, metal and plastic differ sufficiently in this wavelength range, these different materials will each yield a typical reflection signature such that they can be distinguished in the image.

For imaging in the open air, one has been able to make do with (passive) imaging, in which one only uses a mm wave camera. For indoor applications, however, there is not enough "temperature" contrast between the walls of the room, the hidden objects and the carrier of these objects to work with passive systems. Therefore, one has to switch to active lighting [16] by analogy with a flash lamp in ordinary indoor photography. In this spectral domain there are only coherent (“laser-like”) radiation sources, which are not at all suitable for exposure purposes. Such coherent lighting leads to very poor quality images, distorted by noise effects such as speckle, glint, ringing,.... In this project we study active lighting techniques to improve quality and information content in W-band imaging.

Runtime: 2004 - 2007