Structure light telecentric stereoscopic vision 3D measurement system based on Scheimpflug condition

Mei, Qing; Gao, Jian; Lin, Hui; Cui, Yun; He, Yunbo; Wang, Wei; Zhang, Guanjin; Chen, Xin

doi:10.1016/j.optlaseng.2016.05.021

Cited by 35 publications

(10 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The three-dimensional (3D) positional data of the surface are generated by analyzing the structured-light image and developing a positioning algorithm. A 3D-morphology measurement method based on structured light has been applied in a variety of microscopic applications, such as wafer-surface reconstruction (Mei et al, 2016), ball-grid-array testing (Li et al, 2014; Li & Zhang, 2015), and coin-surface reconstruction (Liu et al, 2015). It is one of the noncontact optical measurement methods.…”

Section: Introductionmentioning

confidence: 99%

Surface Reconstruction of Microscale Objects Based on Grid-Patterned Structured-Light Measurements

2021

View full text Add to dashboard Cite

A structured-light projection system was designed for microscale objects with surface heights that ranged from tens to hundreds of microns. The system was composed of a universal projector and microscope system that supported editing the attributes of structured-light patterns in real-time and was capable of projecting microscale patterns. On this basis, reconstructing the metal surfaces of microscale objects based on grid patterns of structured light was investigated, the internal and external parameters of microscope vision and projection systems were calibrated, and an image algorithm for grid-node detection was designed. The results indicated that the proposed method successfully reconstructed the three-dimensional (3D) surface of microscale objects, and the reconstruction results were consistent with the original surfaces. With 95% confidence, the reconstruction precision in the X- and Y-directions was approximately ±4.0 μm and in the Z-direction was approximately ±7.5 μm. The designed system and the proposed method were suitable for 3D-shape measurement of microstructures in microscopic fields and can be adapted to meet a broader range of applications, as compared to current methods.

show abstract

Section: Introductionmentioning

confidence: 99%

Surface Reconstruction of Microscale Objects Based on Grid-Patterned Structured-Light Measurements

2021

View full text Add to dashboard Cite

show abstract

“…[1][2][3] If a measurement setup with a small field-of-view (FOV) is required, telecentric lenses can be employed either in stereo vision (with 4,5 or without additional projector 6,7 ) or in single camera-projector configurations (with entocentric [8][9][10] or telecentric projector 11,12 ) or telecentric Scheimpflug approaches. 13,14 The calibration of a telecentric structured light sensor is not as straightforward as in the entocentric case, as a telecentric camera cannot be modeled by the pinhole camera but requires the introduction of the so-called affine camera model instead. As a telecentric lens ideally only maps parallel light onto the camera sensor, the projection center lies at infinity (cf.…”

Section: Introductionmentioning

confidence: 99%

Calibration routine for a telecentric stereo vision system considering affine mirror ambiguity

et al. 2020

View full text Add to dashboard Cite

A robust calibration approach for a telecentric stereo camera system for threedimensional (3-D) surface measurements is presented, considering the effect of affine mirror ambiguity. By optimizing the parameters of a rigid body transformation between two marker planes and transforming the two-dimensional (2-D) data into one coordinate frame, a 3-D calibration object is obtained, avoiding high manufacturing costs. Based on the recent contributions in the literature, the calibration routine consists of an initial parameter estimation by affine reconstruction to provide good start values for a subsequent nonlinear stereo refinement based on a Levenberg-Marquardt optimization. To this end, the coordinates of the calibration target are reconstructed in 3-D using the Tomasi-Kanade factorization algorithm for affine cameras with Euclidean upgrade. The reconstructed result is not properly scaled and not unique due to affine ambiguity. In order to correct the erroneous scaling, the similarity transformation between one of the 2-D calibration plane points and the corresponding 3-D points is estimated. The resulting scaling factor is used to rescale the 3-D point data, which then allows in combination with the 2-D calibration plane data for a determination of the start values for the subsequent nonlinear stereo refinement. As the rigid body transformation between the 2-D calibration planes is also obtained, a possible affine mirror ambiguity in the affine reconstruction result can be robustly corrected. The calibration routine is validated by an experimental calibration and various plausibility tests. Due to the usage of a calibration object with metric information, the determined camera projection matrices allow for a triangulation of correctly scaled metric 3-D points without the need for an individual camera magnification determination.

show abstract

“…However, experimental results of 3D surface reconstruction are prone to uncertainties [ 33 ]. Recently, optical 3D measurement methods have been developed based on the structured light [ 34 , 35 ]. In such methods, color evaluation is a crucial aspect.…”

Section: Introductionmentioning

confidence: 99%

A Single Image 3D Reconstruction Method Based on a Novel Monocular Vision System

Zhu

2020

Sensors

View full text Add to dashboard Cite

Three-dimensional (3D) reconstruction and measurement are popular techniques in precision manufacturing processes. In this manuscript, a single image 3D reconstruction method is proposed based on a novel monocular vision system, which includes a three-level charge coupled device (3-CCD) camera and a ring structured multi-color light emitting diode (LED) illumination. Firstly, a procedure for the calibration of the illumination’s parameters, including LEDs’ mounted angles, distribution density and incident angles, is proposed. Secondly, the incident light information, the color distribution information and gray level information are extracted from the acquired image, and the 3D reconstruction model is built based on the camera imaging model. Thirdly, the surface height information of the detected object within the field of view is computed based on the built model. The proposed method aims at solving the uncertainty and the slow convergence issues arising in 3D surface topography reconstruction using current shape-from-shading (SFS) methods. Three-dimensional reconstruction experimental tests are carried out on convex, concave, angular surfaces and on a mobile subscriber identification module (SIM) card slot, showing relative errors less than 3.6%, respectively. Advantages of the proposed method include a reduced time for 3D surface reconstruction compared to other methods, demonstrating good suitability of the proposed method in reconstructing surface 3D morphology.

show abstract

Structure light telecentric stereoscopic vision 3D measurement system based on Scheimpflug condition

Cited by 35 publications

References 15 publications

Surface Reconstruction of Microscale Objects Based on Grid-Patterned Structured-Light Measurements

Surface Reconstruction of Microscale Objects Based on Grid-Patterned Structured-Light Measurements

Calibration routine for a telecentric stereo vision system considering affine mirror ambiguity

A Single Image 3D Reconstruction Method Based on a Novel Monocular Vision System

Contact Info

Product

Resources

About