A5035882925- Optical measurement and interference techniques
- Advanced Measurement and Metrology Techniques
- Advanced Surface Polishing Techniques
- Optical Coherence Tomography Applications
- Advanced Numerical Analysis Techniques
- Image Processing Techniques and Applications
- Advanced optical system design
- Medical Imaging Techniques and Applications
- Photoacoustic and Ultrasonic Imaging
- Advanced Vision and Imaging
- Adaptive optics and wavefront sensing
- Radiation Dose and Imaging
- Optical Coatings and Gratings
- Advanced X-ray and CT Imaging
Tianjin University
2019-2023
Xi'an Jiaotong University
2020
In this paper we propose a novel non-contact method of thickness measurement for transparent plate using laser auto-focus scanning (LAFS) probe. Through the analysis focus error signal (FES) from actual specimen's upper and lower surface reflectances, model is introduced to find best position on corresponding plate. Thus, specimen can be obtained. Herein, LAFS probe characteristics by auto-searching FES analyzed, which then realize detection micro-displacements. Therefore, have successfully...
With the introduction of cold electron sources such as nanotubes, X-ray became small in size so that many are installed array to form stationary CT, which brings benefits simplicity mechanism and fast response. However, nanotube-based source is still singly packaged hence density limited, introduces severe sparse-view artifacts could not be used practice. invention device based on ZnO nanowires emitters, a large amount first integrated flat panel device. In this study, we design CT...
3D topography metrology of optical micro-structured surfaces is critical for controlled manufacturing and evaluation properties. Coherence scanning interferometry technology has significant advantages measuring surfaces. However, the current research faces difficulties designing high accuracy efficient phase shifting, characterization algorithms surface metrology. In this paper, parallel unambiguous generalized phase-shifting T-spline fitting are proposed. To avoid ambiguity improve...
Off-axis reflective optical systems find wide applications in various industries, but the related manufacturing issues have not been well considered design process. This paper proposed a method for cylindrical considering constraints to facilitate ultra-precision raster milling. An appropriate index evaluate is established. The optimization solution implemented objective function composed of primary aberration coefficients with weights and constraint conditions structural configuration by...
White-light scanning interferometry (WLSI) has been widely in the field of Nano-Micro topography measurement. In this study , to improve accuracy and robust surface recovery, Fast Fourier Transform-Levenberg Marquardt Algorithm-Phase Shift Interference (FFT-LMA-PSI) algorithm is first proposed position zero optical path difference (OPD), FFT-LMA-PSI a cascaded that involves FFT multiple iterative optimization steps. order computational efficiency, GPU-accelerated developed designed via...
Coherent scanning interference (CSI) faced with the difficulties of accurate phase reconstruction, especially zero optical path difference (ZOPD) in shift method. In this paper, windowed B-spline fitting and least squares method are proposed to accurately compensate ZOPD compared traditional method, provides high accuracy surface quality reconstruction 3D topography. The algorithm avoids introduction complex judgment criterion fringe order correction. Experimental results for a VLSI step...
Accurate characterization of the form error for freeform optics is critical controlled manufacturing and evaluation optical properties. To solve difficulty current surface registration fitting algorithms, improve accuracy point-based spatial path 3D topography metrology, in this paper, improved algorithms are proposed, including a B-spline description optics, point orthogonal projection, parameter optimization, fitting. Limited by angular characteristics an sensor, slope reference frame must...