Laser Speckle in Dynamic Sensing Applications

Laser velocimetry is used as a measurement technique across a variety of fields including mechanical vibration and flow research, medical diagnostics and shock physics. In modern photon Doppler velocimetry (PDV) applications, the perception is that laser speckle pollutes the measured signal, sometimes destroying useful data. Recent experiments suggest the possibility of exploiting speckle to measure transverse speeds, thereby gaining information about surface dynamics across an additional degree of freedom. In this report, we examine the influence of axial displacement and probe characteristics on speckle velocimetry measurement capabilities.