Simultaneous in-plane and out-of-plane deformation measurement by speckle multi-recording method

Microshape Measurement Method Using Speckle Interferometry Based on Phase Analysis

“…However, this analysis technique cannot be used for dynamic analysis because three sheets of speckle patterns are required. In addition, because each speckle before and after the deformation must overlap in the speckle interference measurement [1,22,23], the relationship between the deformation and speckle size poses a problem in largedeformation measurements when the three speckle patterns are captured [24].…”

“…However, when a plane wave is used as the reference beam and the wave plane is angled with respect to the object beam [5], a carrier signal can be provided in the speckle. By providing such a carrier signal and performing a Fourier transform on the captured speckle pattern, the bias and signal components can be separated in the frequency domain [6,7,[23][24][25][26]. The bias component can be removed by extracting only the signal components in this process.…”

“…The bias component can be removed by extracting only the signal components in this process. Thus, the phase component can be obtained using only two speckle patterns before and after deformation [22,23].…”

“…Using such filtering technologies, the phase information in speckle interferometry can be extracted smoothly by a camera and computer technology, such as electronic speckle pattern interferometry (ESPI) [1,2]. Deformation measurements with a resolution of several tens of nanometers were conducted using such technologies [22,23].…”

7.2 - Optoelectronics System for Estimating Measurement Error of Image Pattern Correlation Technique

“…The methods of the second group -optical methods, have an important advantage over the methods of the first -the are non-intrusive. The second group includes many different optical methods: the grid method [1], the moiré method [2], the photoelasticity method [3], the method of holographic and speckle-interferometry [4][5]. The shortcomings of optical methods include the need to make exact copies of the test samples, the complexity of processing the obtained results, and the need to use complex optical systems.…”