SCANNING METHOD AND APPARATUS

摘要

In a terahertz imaging system, a scanning component (105) for scanning a field of view is tracked by an optical beam (115) to obtain positional information. The optical tracking beam (115) can be steered by the scanning component (105) for example by reflection, refraction or diffraction. The steered tracking beam (125) can then be detected by a spatially sensitive detector such as a charge-coupled device array (135). In a preferred embodiment, the output of a terahertz detector (130) receiving terahertz radiation from the scanned field of view (170) is used to modulate the tracking beam (115). This means that the spatially sensitive detector (135) can provide an image directly derived from the scanning of the field of view by the terahertz radiation.