Laser-based, non-contact optical testing is the best choice since it avoids mass loading from direct contact. Thus, Non-contact Laser Doppler vibrometry optical measurement techniques have become an indispensable tool for such characterization – it non-reactively provides the entire frequency range split into phases as well as allowing analysis of transients and decay phases in the time domain.
Now Polytec’s new UHF-120 Ultra-High-Frequency Vibrometer has an extended bandwidth that allows characterization of out-of-plane vibration frequencies bandwidth up to 1.2 GHz and the velocity range to more than 100m/s. Complete with a new optical design, the instrument retains the advantages and features familiar to laser vibrometer users. The system consists of a heterodyne interferometer with a controller box and XY scanning stages. The optical head provides a heterodyne detector signal that is acquired with a fast digital oscilloscope. The digitized detector signal is transferred to a PC where the heterodyne carrier is demodulated by a new software module in Polytec’s Vibsoft package for areal deflection shapes.