Laser Surface Velocimetry Video
Polytec’s LSV laser length & speed sensors are used in a wide variety of industries. Several thousand systems are installed worldwide for mass flow, elongation, cut-to-length, footage counting, speed matching and other length & speed applications. This new LSV video provides an overview of the technology, markets and applications, as well as the benefits compared to traditional contact speed & length measuring techniques.
Laser surface velocimeters use the Doppler principle to evaluate the laser light scattered back from a moving object. Two laser beams superimposed on the surface generate an interference pattern of bright and dark fringes. As the surface moves through the fringe pattern, the intensity of the light scattered from the surface modulates in frequency. This modulation frequency, measured by the sensor’s photo receiver, is directly proportional to the surface velocity.