The three-dimensional measurement of structured light is commonly used and has widespread applications in many industries. In this study, machine learning is used for structured light 3D measurement to recover the phase distribution of the measured object by employing two machine learning models. Without phase shift, the measurement operational complexity and computation time decline renders real-time measurement possible. Finally, a grating-based structured light measurement system is constructed, and machine learning is used to recover the phase. The calculated phase of distribution is wrapped in only one dimension and not in two dimensions, as in other methods. The measurement error is observed to be under 1%.

The traditional microscopic speckle interferometer has limited applications in engineering due to its small field of view. In this paper, we propose a large-field microscopic speckle interferometer which embeds two doublet lens groups in the improved Mach–Zehnder optical path structure to expand its field of view. At the same time, the new system can reduce the coherent noise of reflected light in the optical path. We use this new system to measure the dynamic displacement process of the entire surface of the microchips. The experimental results show that our improved measurement system can achieve large-field, real-time and high-precision dynamic measurement of micro-electromechanical systems (MEMS).

In this paper, a new non-contact and real-time measurement system for Kolsky bars is presented. This system uses two sets of temporal speckle interferometry in-plane displacement measurement devices to replace two strain gauges of conventional Kolsky bars. The in-plane displacement measurement of the Kolsky bar is mainly intended to provide a new test method for the dynamic mechanical properties of small-size material samples with diameters below 2 mm. This method is non-contact, does not require any intermediate medium, and can make the Kolsky bar applicable to characterizing the dynamic mechanical properties of materials under higher strain rates and smaller size conditions. The measuring devices and principles are described. In addition, a preliminary experiment is carried out to demonstrate the performance of this new device.

Traditional thermal stress measurement methods usually assume that the stress is generated only in one direction and cannot measure multidimensional stress components in real time. To realize the real-time and full-field measurement of multiple components of thermal stress, we improved the digital speckle shearing pattern interferometry method and predigested the measurement structure. Additionally, we were able to simplify the measurement process and measure the out-of-plane as well as the in-plane components of the stress tensor at the same time without the symmetric dual-beam illumination or phase-shifting devices. In this article, we demonstrated the possibility of measuring three component gradients ∂ u / ∂ x , ∂ v / ∂ x , and ∂ w / ∂ x , and carried out experiments proving that this method allows for measuring the multicomponent thermal stress measurement of the object under the premise of certain mechanical structure.