Abstract: A method and testing device for the non-destructive testing of at least partial regions of an insulation of a stator winding of an electric machine, in particular a generator of a high-voltage motor, wherein the non-destructive testing is carried out in situ at the installation site of the electric machine using terahertz measurement technology.

Abstract: An apparatus for time-resolved capture of pulsed electromagnetic radio frequency radiation includes a generator being so adapted that in operation of the apparatus the generator produces pulses of the electromagnetic radio frequency radiation, a detector being so adapted that in operation of the apparatus the detector captures the field strength of the pulses reflected by a sample as a function of time, and a distance measurement system and an evaluation device connected to the detector and the distance measurement system. The distance measurement system is so adapted that in operation of the apparatus the distance measurement system captures a change in a distance between the generator and the sample and/or between the sample and the detector as a function of time.

Abstract: The present invention relates to a laser including a laser amplifier and a laser resonator. The laser amplifier includes a disk-shaped active medium having a reflector. The active medium rests on a cooling means for cooling said active medium and said reflector. The reflector embodies a mirror of said laser resonator. The laser amplifier includes an optical means for refocusing a pumping light configured for repeatedly deviating said pumping light and refocusing said pumping light onto the active medium for causing a multiple passage of said pumping light through said active medium. Such a thin-disk laser is not prone to thermal lensing. According to the invention, the laser resonator is formed as a ring resonator. Two optical waves can travel around within the ring resonator in different directions. An optical selection means is provided for giving preference to propagation of one of the both optical waves traveling around that can be coupled out as an output laser beam.

Abstract: The present invention relates to a laser comprising a laser amplifier and a laser resonator. The laser amplifier comprises a disk-shaped active medium having a reflector. The active medium rests on a cooling means for cooling said active medium and said reflector. The reflector embodies a mirror of said laser resonator. The laser amplifier comprises an optical means for refocusing a pumping light configured for repeatedly deviating said pumping light and refocusing said pumping light onto the active medium for causing a multiple passage of said pumping light through said active medium. Such a thin-disk laser is not prone to thermal lensing. According to the invention, the laser resonator is formed as a ring resonator. Two optical waves can travel around within the ring resonator in different directions. An optical selection means is provided for giving preference to propagation of one of the both optical waves traveling around that can be coupled out as an output laser beam.