International Symposium on Laser Metrology最新文献_第8页

NDT detection and quantification of induced defects on composite helicopter rotor blade and UAV wing sections 复合材料直升机旋翼叶片和无人机翼段诱导缺陷的无损检测与量化

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814560

D. Findeis, J. Gryzagoridis, V. Musonda

{"title":"NDT detection and quantification of induced defects on composite helicopter rotor blade and UAV wing sections","authors":"D. Findeis, J. Gryzagoridis, V. Musonda","doi":"10.1117/12.814560","DOIUrl":"https://doi.org/10.1117/12.814560","url":null,"abstract":"Digital Shearography and Infrared Thermography (IRT) techniques were employed to test non-destructively samples from aircraft structures of composite material nature. Background information on the techniques is presented and it is noted that much of the inspection work reviewed in the literature has focused on qualitative evaluation of the defects rather than quantitative. There is however, need to quantify the defects if the threshold rejection criterion of whether the component inspected is fit for service has to be established. In this paper an attempt to quantify induced defects on a helicopter main rotor blade and Unmanned Aerospace Vehicle (UAV) composite material is presented. The fringe patterns exhibited by Digital Shearography were used to quantify the defects by relating the number of fringes created to the depth of the defect or flaw. Qualitative evaluation of defects with IRT was achieved through a hot spot temperature indication above the flaw on the surface of the material. The results of the work indicate that the Shearographic technique proved to be more sensitive than the IRT technique. It should be mentioned that there is \"no set standard procedure\" tailored for testing of composites. Each composite material tested is more likely to respond differently to defect detection and this depends generally on the component geometry and a suitable selection of the loading system to suit a particular test. The experimental procedure that is reported in this paper can be used as a basis for designing a testing or calibration procedure for defects detection on any particular composite material component or structure.","PeriodicalId":191475,"journal":{"name":"International Symposium on Laser Metrology","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122729113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Characterization of optical surfaces for the present generations of synchrotron sources 当代同步加速器光源光学表面的表征

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814695

M. Thomasset, F. Polack

{"title":"Characterization of optical surfaces for the present generations of synchrotron sources","authors":"M. Thomasset, F. Polack","doi":"10.1117/12.814695","DOIUrl":"https://doi.org/10.1117/12.814695","url":null,"abstract":"Generalization of specific optical metrology and systematic testing of all delivered components has yield in the last decade to a significant improvement of the optical surfaces installed on synchrotron radiation (SR) beamlines around the world. Surface roughness is classically characterized by phase-shift interferential microscope, sometimes AFM. Long trace profiler (LTP)1, which measures the local slope along a line profile, has been the choice instrument to measure figure errors of large size components. Present LTPs have accuracy around 0.2 μrad RMS, and a spatial resolution around 1 mm, but they cannot provide 2D measurement nor access the small radii that modern sagitally focusing SR optics calls for. Stiching interferometry or Shack-Hartmann methods are good candidate for 2D measurement of figure errors. With increasing quality of mirrors and increasing coherence of synchrotron sources the simple specification of surface figure by the RMS slope errors of low spatial frequencies and roughness by the standard deviation of the high frequency surface height fluctuation is becoming less and less relevant. In order to achieve given performances the properties of an optical surface are better specified by the power spectrum of the surface errors in different spatial frequency ranges, the definition of which depends on the actual use of the surface. Evaluating the quality of SR mirrors used to form micro or nano X-ray probes should be checked by modeling the point spread function. It requires an accurate measure of the surface shape in the low frequency range. The next step of SR optics improvement will come from local polishing techniques guided by metrology. The required level of accuracy is calling for a panel of measuring methods adapted to different spatial frequency that are still under development.","PeriodicalId":191475,"journal":{"name":"International Symposium on Laser Metrology","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124829107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Phase shifting interferograms processing for fiber point-diffraction interferometer 光纤点衍射干涉仪相移干涉图处理

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814552

Liang Nie, Jun Han, Xun Yu, B. Liu, Xu Jiang, Fang Wang

{"title":"Phase shifting interferograms processing for fiber point-diffraction interferometer","authors":"Liang Nie, Jun Han, Xun Yu, B. Liu, Xu Jiang, Fang Wang","doi":"10.1117/12.814552","DOIUrl":"https://doi.org/10.1117/12.814552","url":null,"abstract":"To characterize the spherical surface of extreme ultraviolet (EUV), the fiber phase shifting point-diffraction interferometer (FPS/PDI) has recently been designed and implemented. The diffraction wavefront from an optical fiber acts as the perfect referenced spherical wave and new-style interferometer configuration is used. The laboratory apparatus has been put up to measure spherical surface in experiment. The main content of this paper is the key technique of FPS/PDI about the method of interference image processing and the precision analysis for the interferometer. In experiment apparatus, a concave spherical surface is measured and a piezoelectric ceramics (PZT) is used for phase shifting. The wrap phase distribution is got by five-step phase shifting method, and then the unweighted least-squares phase unwrapping algorithm is optimized and used to obtain the unwrapped phase distribution. The error of spherical figure is derived from the fitting method of Zernike polynomials. The data processing result is analyzed in comparison with the measurement result of ZYGO interferometer. The repeat precision of the FPS/PDI is evaluated by multimeasurement. Finally, the major error sources are discussed and some optimized methods for the system are proposed.The results show that the interferometer has achieved worthy measurement precision and has great development potential.","PeriodicalId":191475,"journal":{"name":"International Symposium on Laser Metrology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128479446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Whole field residual stress measurement using computer aided reflection grating 计算机辅助反射光栅全场残余应力测量

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814586

C. Ng, Y. Goh, A. Asundi

引用次数: 3

Phase retrieval in digital holographic interferometry based on complex phasor and short time Fourier transform 基于复相和短时傅里叶变换的数字全息干涉相位恢复

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814555

Wen Chen, C. Quan, C. Tay

引用次数: 0

Raman scattering from Zn/ZnO core-shell nanoparticles Zn/ZnO核壳纳米粒子的拉曼散射

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814621

G. Bajaj, R. K. Soni

引用次数: 0

Investigation of light scattering for scratch detection 用于划痕检测的光散射研究

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814606

Z. Zhong, L. Zhao, L. Wang

引用次数: 1

Study on a new method for measuring volumetric error of CMM 测量三坐标测量机体积误差新方法的研究

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814553

Enxiu Shi, Junjie Guo, Yumei Huang

引用次数: 0

A double-prism lateral shear interferometer for wavefront analysis and collimation testing 用于波前分析和准直测试的双棱镜横向剪切干涉仪

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814546

K. U. Hii, K. Kwek

引用次数: 1

Measurement of human embryonic stem cell in the growing cycle 人胚胎干细胞生长周期的测定

International Symposium on Laser Metrology Pub Date : 2008-09-29 DOI: 10.1117/12.814615

X. Li, L. Zhao, Steve Oh, W. Chong, J. Ong, A. Chen, A. Choo

引用次数: 0