FLOW MEASUREMENT BY USING HOLOGRAPHIC INTERFEROMETRY

High precision deformation measurement by digital phase shifting holographic interferometry.

A digital phase shifting technique capable of quantitatively determining the phase of holographic interferometric displacement fringes is presented. This technique uses computer control to take data and calculate surface deformation. The phase value at each detector point can be calculated by taking four successive intensity data frames with the reference phase shifted between each frame. The d...

Four-dimensional dynamic flow measurement by holographic particle image velocimetry.

The ultimate goal of holographic particle image velocimetry (HPIV) is to provide space- and time-resolved measurement of complex flows. Recent new understanding of holographic imaging of small particles, pertaining to intrinsic aberration and noise in particular, has enabled us to elucidate fundamental issues in HPIV and implement a new HPIV system. This system is based on our previously report...

Measuring the deposited energy from a non-ionizing laser beam in water by digital holographic interferometry

Digital Holographic interferometry is a powerful and widely used optical technique for accurate measurement of variations in physical quantities such as density, refractive index, and etc. In this study, an experimental digital holographic interferometry setup was designed and used to measure the amount of energy changes induced by absorption of radiation from a non-ionizing infrared laser beam...

Incoherent Holographic Interferometry

Digital Holographic Piv for 3d Flow Measurement

We have developed a simple digital holographic PIV system for 3D measurement of turbulent and multiphase flow. This system records in-line holograms of tracer particles directly on a digital camera and reconstructs the 3D particle field numerically. Using a novel complex amplitude-based method, we are able to overcome the depth of focus problem and the speckle noise problem associated with the ...