Speckle interferometer for vibration analysis up to 1 GHz
The Tempo series is based on the principle of two-wave photorefractive mixing. This method can already represent frequencies from 1 kHz and is theoretically not limited to high frequencies.
The output signal is a time-variable analog voltage that is proportional to the instantaneous surface shift in the nm range. The upper cut-off frequency is up to 1 GHz, depending on the type.
Tempo 1D
The Tempo 1D is an ultra-high frequency (UHF) laser interferometer and is able to detect surface displacements caused by the propagation of UHF ultrasound up to GHz. The system measures the spatial component vertical to the surface of the tested object. It is used for the characterization of micro and nano components.
Tempo 2D
The Tempo 2D can simultaneously measure two components of surface displacement, out-of-plane motion and in-plane motion, with a single laser probe and a single collection optic. The determination of the in-plane component enables efficient detection of shear waves, especially when the ultrasound propagation direction is perpendicular to the surface under test. The system is able to reconstruct the entire ultrasonic field.
Application examples
- Material investigation over the complete volume, e.g. representation of blowholes deep inside a metal body
- Thickness measurement of any body
- Representation of holes or defects on the back of an object
- Representation of delamination on composite materials such as GFRP and CFRP. Pulsed detection lasers can be used to avoid thermal damage to the material.
Advantages
- Very high upper cut-off frequency (approx. 1 GHz)
- Very low lower cut-off frequency (approx. 1 kHz)
- Simultaneous detection in plane 90° to plane possible (1D and 2D)