Abstract: A measuring apparatus is provided for inspecting a seal of an item. The measuring apparatus includes a radiation source for providing radiation for illuminating the seal of the item, a detector for receiving radiation from the item for generating a corresponding detected signal, and a processing arrangement for processing the detected signal to generate an output signal indicative of a state of the seal. The radiation source is arranged to focus the radiation into a plurality of focal points at the seal of the item, wherein the focal points are mutually spatially spaced apart. Moreover, the detector is arranged to image one or more of the focal points and to be selectively sensitive to an intensity of radiation received from the one or more focal points to generate a detected signal.

Abstract: In the measuring device and measuring method, confocal measuring principle is utilized. A certain component of an optical measurement signal is, from the point of view of both illumination and imaging, in focus only at one point on the virtual measuring surface. In the measuring device, the surface to be measured always hits a common focus point of the illumination and imaging, whereby a reflection is generated. The reflected optical signal is directed to a detector belonging to the imaging unit, where one picture element of the detector corresponds to a certain focus point, respectively. The optical efficiency received by each picture element is indicated. The light reflecting from the intersection of the virtual measuring surface and the surface of the object produces an intensity maximum for the detector. This maximum point is indicated and converted in the imaging unit (13) into the height of the surface of the object.

Abstract: A measurement device for the determination of the characteristics of the object's surface by means of the optical radiation, wherein a measurement device comprises an optical radiation source and a detector to receive the radiation reflected from the surface being measured. In addition, a measurement device comprises an emitted optical radiation processing unit, which is adjusted to split optical radiation emitted by an optical source into separate wavelengths and to direct said separate wavelengths to the object being measured in a direction, that differs from the normal of the surface being measured so, that at least the shortest and the longest wavelengths of said wavelengths are focused on different halves and different heights of the measured object's surface, in the direction of the normal of the surface being measured.