Method and apparatus for interferometric vibration measurement at a plurality of a measurement points by means of a measuring laser beam

An apparatus for interferometric vibration measurement at a multiplicity of measurement points using a measurement laser beam (1), the apparatus comprising:

• one or more radiation sources configured for generating a measurement laser beam (1) in an infrared wavelength range and a pilot laser beam (2) in a visible wavelength range,
• a deflection unit (8) is arranged in the beam path of the measurement laser beam (1) and the pilot laser beam (2),
• a control unit (9) connected to the deflection unit (8) in order to direct the measurement laser beam (1) and the pilot laser beam (2) onto a multiplicity of measurement points on a measurement object (16),
• an interferometer unit (5, 5′) configured to superimpose the measurement beam at least partially reflected and/or scattered by the measurement object (16) with a reference beam to form optical interference on a detector surface of an interference detector (6) of the apparatus, the interference detector (6) being connected to the control unit (9) in order to evaluate vibration data,
• the control unit (9) is configured to direct the pilot laser beam (2) onto a measurement point as a function of control instructions by the deflection unit (8),
• in a correction step, is configured to actuate the deflection unit (8) in order to compensate for an angular deviation (11) between the pilot laser beam (2) and the measurement laser beam (1), and, after performing the correction step, is further configured to carry out a vibration measurement at the measurement point using the measurement laser beam (1).