Abstract: The invention relates to a device and a method for the measurement of the curvature of a surface (1), which is more exact and less expensive than prior art devices. The device comprises a light source (2) for the irradiation of a light beam (3) onto the surface (1), in which a birefingent element (4) is arranged between light source (2) and surface (1), in which furthermore a detector (5) is arranged for the detection of the partial beams (6,7), that are reflected from the surface (1), and at least one main axis (17) of the birefringent element (4) is positioned with respect to the light beam (3) of the light source (2) in such a way, that the light beam (3) of the light source (2) is split up into at least two parallel beams (6,7).

Abstract: Air decontamination devices in one example include a filter directly exposed to ultraviolet (“UV”) radiation on an upstream side and a downstream side. Ozone may be provided to permeate the filter, as well. Reflectors may be provided to reflect UV radiation emitted in a direction away from the filter, towards the filter. The filter may be a V-bank filter, for example. Air sampling ports and prefilters may be provided. The air decontamination units may be used to decontaminate the air after industrial and medical contaminations and terrorist biological, chemical and radiological attacks, for example. Mobile isolation units, and methods of decontaminating rooms, are disclosed, as well.