Speckle interferometry with temporal phase evaluation for measuring large-object deformation

Joenathan, C.; Franze, B.; Haible, P.; Tiziani, Hans J.

doi:10.1364/ao.37.002608

Cited by 138 publications

(53 citation statements)

References 5 publications

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“…This similarity has been noted in the literature by Briers in his paper [ 16 ] reconciling ESPI and LDV, as well as being briefly mentioned by Cloud in his book on optical methods [ 17 ] and implicitly understood by Joenathan in his papers on TSPI. [6][7][8] It seems desirable to the current authors to highlight the similarities and differences in the approach, to briefly derive the equations, and to reconcile the approaches in more detail than is contained in any of these references. For simplicity in illustrating both concepts, a Michelson interferometer arrangement, shown in Figure 1, is used for the discussion.…”

Section: Reconciling Tspi and Dopplermentioning

confidence: 99%

“…(11) As mentioned in the Section 1.1.1, the camera measures only irradiance, which is computed in Equation (6). Using Equations (9) thru (11), the resulting modulated irradiance measured at the camera simplifies to (13) Note that all terms on the order of the optical frequency (ω λ ) are integrated to apparent DC (i.e.…”

Section: Laser 532 Nmmentioning

confidence: 99%

“…The WLDV uses only the time-varying irradiance of a given pixel to determine the velocity via frequency domain methods. If the velocity were constant throughout the entire test, as done in the TSPI work by Joenathan, [6] the Fast Fourier Transform (FFT) would contain only a single frequency peak. This is typically an acceptable constraint for displacement measurements, but unacceptable when taking velocity measurements where the velocity is both a function of location on the object and time.…”

Section: Joint Time Frequency Analysis-tracking Velocity Changes In Timementioning

confidence: 99%

“…In the TSPI literature, a number of approaches are used to decode the time-varying irradiance of the pixels. Frequency-based methods are the most similar to Doppler velocimetry, [6][7][8][9] but re-curvature methods, [10] scanning phase methods, [11,12] and temporal branch-cut methods have also been utilized. [13,14] Another unique approach to obtain full-field velocity information is a system termed optically phase-locked ESPI.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Widefield laser doppler velocimeter: development and theory.

Hansche¹,

Reu²,

Massad³

2007

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The widefield laser Doppler velocimeter is a new measurement technique that significantly expands the functionality of a traditional scanning system. This new technique allows full-field velocity measurements without scanning, a drawback of traditional measurement techniques. This is particularly important for tests in which the sample is destroyed or the motion of the sample is non-repetitive. The goal of creating "velocity movies" was accomplished during the research, and this report describes the current functionality and operation of the system. The mathematical underpinnings and system setup are thoroughly described. Two prototype experiments are then presented to show the practical use of the current system.

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Section: Reconciling Tspi and Dopplermentioning

confidence: 99%

Section: Laser 532 Nmmentioning

confidence: 99%

Section: Joint Time Frequency Analysis-tracking Velocity Changes In Timementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Widefield laser doppler velocimeter: development and theory.

Hansche¹,

Reu²,

Massad³

2007

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“…Optical methods such as fringe projection, 9) electronic speckle pattern interferometry (ESPI) 10,11) and phase-shifting digital holography (PSDH) 1214) are useful to measurement shape, displacement and strain distribution in full-field of structures. However, the measurement area of these interferometric methods is still small.…”

Section: Introductionmentioning

confidence: 99%

Noncontact Deflection Distribution Measurement for Large-Scale Structures by Advanced Image Processing Technique

Numayama

Saka

et al. 2012

Mater. Trans.

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Ambient unexpected vibration in field experiment for large-scale structures is an essential problem to perform highly accurate displacement measurement. In this paper, an advanced image processing (AIP) technique combining the sampling moiré method and digital image correlation (DIC) method is developed for noncontact measuring deflection distribution of large-scale structures. This technique has demonstrated promising results in both laboratory and field experiments. Experimental results in laboratory show that the artificial vibration can be abated remarkably by DIC using a subset image of background without loading. Experimental results in field show that AIP technique can successfully measure the displacement distribution of a long crane with sub-millimeter deflection under natural vibration environment. The most attractive advantage of AIP technique is only each single image is required before and after deformation. This indicates the noncontact deflection distribution measurement is possible with high resolution and high accuracy by ease setup for the dynamic structural evaluation of infrastructures.

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Speckle and Speckle Metrology

Joenathan

Tiziani

2004

Digital Encyclopedia of Applied Physics

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Speckles are a three-dimensional self interference pattern formed by a large number of random coherent waves. This results in a granular structure in free space or can be observed to be superposed on the image of the object and sets a fundamental limitation in high-resolution hologram microscopy and coherent imagery. Essentially, speckles are a randomly coded pattern that carries information about the object surface, and also has the rare distinction of being a nuisance and simultaneously a useful tool for measurement. Emergence of better measurement capabilities, newer recording media, faster computers and interfaces, and software has revitalized speckle metrology and has resulted in many fascinating new developments. Scores of books and review articles cover the myriads of applications and developments, and this chapter is intended to provide a concise and precise account of speckles starting from its infancy to the latest developments such as temporal speckle pattern interferometry or digital holography. Attractiveness of speckle methods lies in their ability to measure: large deformations, displacements with variable sensitivity to in-plane and out-of-plane, displacement derivatives, shape of a three-dimensional object, surface roughness, and dynamic displacement. Speckle techniques can nowadays be used to measure a wide range of displacement, sensitivities ranging from 0.25 µm to 150 µm for in-plane and 0.05 to 150 µm for out-of-plane displacements and with shearing techniques to over a 1000 µm. Speckle and Speckle MetrologyKeywords speckle; speckle photography; speckle interferometry; electronic speckle pattern interferometry; digital holography.

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Speckle interferometry with temporal phase evaluation for measuring large-object deformation

Cited by 138 publications

References 5 publications

Widefield laser doppler velocimeter: development and theory.

Widefield laser doppler velocimeter: development and theory.

Noncontact Deflection Distribution Measurement for Large-Scale Structures by Advanced Image Processing Technique

Speckle and Speckle Metrology

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