Displacements measurement in a building model using the speckle photography technique

González-Peña, Rolando J.; Anda, Rosa María Cibrián Ortiz de; Pino-Velazquez, Angel J; Cruz, José Anderson Santos; Buron, Charlotte; Palmer, Rosario Salvador; Gómez, Mateo Buendía

doi:10.1016/j.engstruct.2005.06.009

Cited by 4 publications

(2 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5 The displacement direction is perpendicular to the fringe direction. The displacement of specimen is inversely proportional to the fringe spacing.…”

Section: Acquisition Of Speckle Pattern Interference Fringes Imagementioning

confidence: 99%

“…The most basic principle of speckle metrology is to measure in-plane displacement of object surface and some parameters of space displacement field and strain field by speckle doubleexposure technique. Recently, there has been much research on measurement for displacement of objects by speckle method, [3][4][5][6] which can realise non-contact measurement and high accuracy.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Morphological image processing in the speckle metrology

Liu

Zhao

2011

The Imaging Science Journal

View full text Add to dashboard Cite

In the speckle metrology, the processing of speckle image is very important. A method of morphological image processing is proposed in this paper. The theory of mathematical morphology and some basic morphological operations are introduced. In the experiment of laser speckle double-exposure, we get the specklegram which contains the information of micro-displacement. Then we employ the device of point-to-point analysis and get the image of laser speckle pattern interference fringes. Using the theory of speckle, the formula of micro-displacement is obtained. In the image processing, we first use grey-level transformation and histogram equalisation. Then we use the method of dynamic local threshold to get the binary image of laser speckle pattern interference fringes. In order to extract the fringe spacing, the image is processed by the operations of mathematical morphology in this work, such as the operations of opening, closing, skeletonisation and deburring. After that, the image can be used to extract the average fringe spacing by which the micro-displacement can be calculated finally. We get a more accurate result than traditional methods. The deviation may be less than 1% and the order of magnitude can reach 1 mm. The method of morphological image processing used in the speckle metrology has some advantages such as fast processing, easiness and high precision.

show abstract

“…5 The displacement direction is perpendicular to the fringe direction. The displacement of specimen is inversely proportional to the fringe spacing.…”

Section: Acquisition Of Speckle Pattern Interference Fringes Imagementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Morphological image processing in the speckle metrology

Liu

Zhao

2011

The Imaging Science Journal

View full text Add to dashboard Cite

show abstract

Advances in Speckle Metrology

Joenathan

Sirohi

Bernal

2015

The Optics Encyclopedia

View full text Add to dashboard Cite

The field of speckle metrology has seen a surge in development in the past 10 years owing to advancements in digital cameras and computing power. For instance, a variety of digital speckle correlation (DSC) processes can now be performed in almost real time and therefore speckle techniques has found applications in nondestructive testing (NDT), biology, and medicine. New techniques in terms of optical arrangements and in extracting phase data have been introduced for measuring out‐of‐plane and in‐plane motions in digital speckle interferometry (DSPI) and digital speckle shear interferometry (DSSPI). DSC, DSPI, and DSSPI have also been combined to extend the range of measurements. In addition, quantitative analysis in speckle interferometry has seen a plethora of new software developments for conducting real‐time, accurate, complicated, fast, and repeatable measurements with ease. In addition, different methods to process speckle fringes have made analysis equivalent to that of classical interferometry, yet can be applied to all types of real‐world specimen.

show abstract