Abstract: A device for the optical non-contact vibration measurement of an vibrating object, including a laser Doppler vibrometer that has a laser as the light source for a laser beam, a first beam splitter assembly for splitting the laser beam into a measuring beam and a reference beam, a means for shifting the frequency of the reference beam or of the measuring beam in a defined manner, a second beam splitter assembly by which the measuring beam back-scattered by the oscillating object is merged with the reference beam and superimposed on the same, and a detector for receiving the superimposed measuring and reference beam and for generating a measurement signal. The laser is provided with a polarization filter arranged inside the optical resonator of the laser and the laser is frequency stabilized by regulating to a beat signal of the laser.

Abstract: A device for the optical non-contact vibration measurement of an vibrating object, including a laser Doppler vibrometer that has a laser (1) as the light source for a laser beam, a first beam splitter assembly (S1) for splitting the laser beam into a measuring beam (2) and a reference beam (3), a means (4) for shifting the frequency of the reference beam (3) or of the measuring beam (2) in a defined manner, a second beam splitter assembly (S2, S3) by which the measuring beam (2) back-scattered by the oscillating object (6) is merged with the reference beam (3) and superimposed on the same, and a detector (5) for receiving the superimposed measuring and reference beam (7) and for generating a measurement signal. The laser (1) is provided with a polarization filter arranged inside the optical resonator of the laser and the laser (1) is frequency stabilized by regulating to a beat signal of the laser.