Abstract: A device for precision measurement of shafts, spindles, or the like calls for two surfaces which are combined with one another, of which one is partially reflecting and the other is roughly fully reflecting. These surfaces reflect an incident light beam independently of one another onto a single optoelectronic target. The target can be read out two-dimensionally and is pixel-oriented. From only a single measurement position, the azimuth and elevation, and the parallel offset between the incident light beam and a center of the reflecting surfaces can be determined.

Abstract: The invention relates to a process for testing of a workpiece by means of eddy currents induced by a field coil in the workpiece and from which a measurement signal is obtained by means of a measurement sensor, a pattern signal representative of a workpiece fault being generated, a correlation function of the measurement signal acquired by the sensor with the pattern signal being determined, and the correlation function being evaluated in order to detect a fault in the workpiece. The invention furthermore relates to a device for executing the process.

Abstract: A method for scanning a plurality of optical measuring reflectors adapted to reflect a scan beam in a position-related manner to a position detector, which supplies signals relating to the position of the beam incidence point in the detector plane. So far a separate scan beam has been generated for each measuring reflector and there has been a separate position detector for use therewith. In accordance with the invention a single common linearly polarized scan beam L1 and a single common detector D are provided and by turning the plane of polarization of the scan beam under electronic control and by the use of further optical means the scan beam is switched over as desired to a selected measuring reflector, which then reflects the incident scan beam to the common position detector D in position-related manner.

Abstract: A method for checking the coaxial alignment of tandem-arranged shafts involving the detection of a coaxial in-line or an offset state of the said shafts. In different angular positions of measurement two independent signals are produced related to any parallel offset and any angular offset of the shafts respectively. In the known methods the angular positions of measurement are bound by a mutual angular spacing of 90.degree.. This leads to problems if there are obstructions in these angular positions of measurement of the device used for measuring. The method in accordance with the invention makes possible alignment checking operations using freely selectable angular positions of measurement.