True near field versus contrast near field imaging.

International audienceWe demonstrate that in near field imaging, interaction between light and sample can be divided into two main areas: the true near field and the contrast near field domain. We performed extensive numerical simulations in order to identify the limits of these areas, and to investigate contrast near field imaging in which much easier propagation calculation can be achieved. Finally, we show an application with terahertz axonal imaging. © 2006 Optical Society of Americ