Results 21 to 30 of about 394 (147)

An Improved Circular Fringe Fourier Transform Profilometry

Sensors, 2022
Circular fringe projection profilometry (CFPP), as a branch of carrier fringe projection profilometry, has attracted research interest in recent years. Circular fringe Fourier transform profilometry (CFFTP) has been used to measure out-of-plane objects ...
Qili Chen, Mengqi Han, Ye Wang, Wenjing Chen   +3 more
doaj   +1 more source

A Separation Method of Superimposed Gratings in Double-Projector Fringe Projection Profilometry Using a Color Camera

Applied Sciences, 2021
Fringe projection profilometry has been intensively studied for several decades. However, due to the limitation of the field range of a single projector, when measuring objects with complex surfaces, there are always shadow areas in the captured images ...
Yuanjun Zhang, Xinghua Qu, Yiming Li, Fumin Zhang   +3 more
doaj   +1 more source

Light-Field-Assisted Phase Unwrapping of Fringe Projection Profilometry

IEEE Access, 2021
A phase unwrapping algorithm assisted by light field without additional time coding is proposed, which can be used in various aspects of optical imaging and metrology.
Ziwei Wang, Yang Yang, Xiaoli Liu, Yupei Miao, Quanyao Hou, Yongkai Yin, Zewei Cai, Qijian Tang, Xiang Peng   +8 more
doaj   +1 more source

Intensity-Averaged Double Three-Step Phase-Shifting Algorithm with Color-Encoded Fringe Projection

Photonics, 2022
Fringe projection profilometry (FPP) has been broadly employed for three-dimensional shape measurements. However, the measurement accuracy suffers from gamma nonlinearity.
Yuwei Wang, Haojie Zhu, Jiaxu Cai, Yajun Wang   +3 more
doaj   +1 more source

3D Measurement of Discontinuous Objects with Optimized Dual-frequency Grating Profilometry

Measurement Science Review, 2021
Three-dimensional profilometry tends to be less effective at measuring discontinuous surfaces. To overcome this problem, an optimized profilometry based on fringe projection is proposed in this paper.
Che Jun, Sun Yanxia, Jin Xiaojun, Chen Yong   +3 more
doaj   +1 more source

Virtual 3D surface imaging system for the validation of tumor tracking algorithm used in surface-guided radiotherapy. [PDF]

J Appl Clin Med Phys
Abstract Purpose To develop a surface 3D reconstruction simulation system based on the Phase Measurement Profilometry (PMP) and the Unity physics engine and validate its feasibility for assisting in the development of the Surface‐Guided Radiotherapy (SGRT) tumor tracking algorithm.
Wu X, Wei Z, Zhai S, Zhang Y, Liu Z, Jiang T, Zhang L, Qian J.   +7 more
europepmc   +2 more sources

High-Accuracy Three-Dimensional Deformation Measurement System Based on Fringe Projection and Speckle Correlation

Sensors, 2023
Fringe projection profilometry (FPP) and digital image correlation (DIC) are widely applied in three-dimensional (3D) measurements. The combination of DIC and FPP can effectively overcome their respective shortcomings. However, the speckle on the surface
Chuang Zhang, Cong Liu, Zhihong Xu
doaj   +1 more source

Adapted Fringe Projection Sequences for Changing Illumination Conditions on the Example of Measuring a Wrought-Hot Object Influenced by Forced Cooling

Sensors, 2021
Optical 3D geometry reconstruction, or more specific, fringe projection profilometry, is a state-of-the-art technique for the measurement of the shape of objects in confined spaces or under rough environmental conditions, e.g., while inspecting a wrought-
Lorenz Quentin, Rüdiger Beermann, Carl Reinke, Pascal Kern, Markus Kästner, Eduard Reithmeier   +5 more
doaj   +1 more source

Fringe Order Correction for Fringe Projection Profilometry Based on Robust Principal Component Analysis

IEEE Access, 2021
Temporal phase unwrapping is among the most robust and efficient phase unwrapping methods in fringe projection profilometry. They can recover the fringe orders even in the presence of surface discontinuities. However, fringe order errors may occur due to
Yiwei Zhang, Jun Tong, Lei Lu, Jiangtao Xi, Yanguang Yu, Qinghua Guo   +5 more
doaj   +1 more source

Noninvasive Assessment Methods for the Therapeutic Effect Following Facial Rejuvenation. [PDF]

J Cosmet Dermatol
ABSTRACT Background As the demand for facial rejuvenation continues to rise, monitoring the response to therapy is worthy of attention. However, a standardized system for assessing therapeutic effects is currently lacking. This study aims to review the existing noninvasive efficacy evaluation tools for facial rejuvenation and analyze their advantages ...
Zhao S, Wang M, Lai X, Yan Y.
europepmc   +2 more sources