Vibration phase mapping using holographic optical element-based electronic speckle pattern interferometry

摘要

An out-of-plane sensitive electronic speckle pattern interferometer (ESPI) using holographic optical elements (HOEs) for vibration phase mapping is reported. Constant phase contours across a sinusoidally vibrating circular metal plate are mapped using reference beam phase modulation in the unbalanced HOE based ESPI system. Reference phase modulation is implemented by modulating the drive current of a laser diode. The correlation fringes were obtained using the time average ESPI method. The phase measurement accuracy depends on the vibration amplitude of the object.