Lin Xue, Hiromasa Suzuki, Yutaka Ohtake, Hiroyuki Fujimoto, Makoto Abe, Osamu Sato, Toshiuuki Takatsuji
Recently, due to the ability to precisely measure inner and outer structure of a specimen in one single scan, X-ray computed tomography (CT) has entered the field of dimensional metrology in industry. Unfortunately, it is very difficult to realize industrial-level accuracy with CT for various factors. In this paper we analyze one of the most serious effects, the FDK (Feldkamp–Davis–Kress) effect, which can be observed in most of the common X-ray CT scanners with a cone beam. The FDK is the well-know reconstruction algorithm widely accepted as a standard reconstruction method for cone beam...
TC14 LMPMI Symposium 2014
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· 2014
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Osamu Sato, Hiroyuki Fujimoto, Sonko Osawa, Makoto Abe, Toshiyuki Takatsuji
Form and dimensional measurements using X-ray Com- puted Tomography (X-ray CT) are useful on product development, reverse engineering, production control and quality certification because X-ray CT system can get three dimensional volumetric data of the full body of the target object at one time. Generally, three dimensional coordinate measuring systems (CMSs), in which X-ray CTs are also included, have measurement space distorted by the kinematic and other factors. Therefore, the deformation of the measurement space should be compensated for precise dimensional measurement. Moreover, the...
TC14 LMPMI Symposium 2014
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Meiyun Chen, Soichiro Ueda, Satoru Takahashi, Kiyoshi Takamasu
This paper analyses existing techniques and proposes a newly technology named Multi-Beam Angle Sensor (MBAS) for measuring the roundness errors. Comparing with other methods, MBAS has just used one sensor and independence on the rotary stage, and can be used as a simple and convenient one in factory-level. Stability can also be improved by using the MBAS. In this paper, the optical probe is based on the principle of autocollimator and has a stability of 0.3 arcsec. Unlike multi- probe methods, the MBAS is constructed to realize the roundness measurement by using only one probe, which is less...
TC14 LMPMI Symposium 2014
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Adam Wo?niak, Grzegorz Krajewski
Scanning probes CMM became currently treated as a standard in coordinate metrology. Not only because of high quantity of data gathering in short time of probing but also scanning technology significantly decrease the inspection time. Modern manufacturing, especially in highly competitive economy, required more efficient measuring machine and processes, because inspection machine quite often become the bottle neck in whole manufacturing process. More efficient in coordinate metrology means faster cycles of measurement with acceptable accuracy. But in fact, scanning speed significantly...
TC14 LMPMI Symposium 2014
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Hengyan Zhou, Lijiang Zeng
Planar encoders can be used to measure two-dimensional (2D) displacements. In order to achieve large measuring ranges, planar encoders require large-size 2D gratings, which can be made by optical mosaic technique. We set up a dual Lloyd’s mirror interferometer to make optical mosaic 2D gratings. The key point to obtain good mosaic gratings is to fine tune the attitude and position of the substrate relative to the exposure beams during consecutive exposures, which can be realized by utilizing the interference fringes formed by the diffraction of the exposure beams from the latent gratings...
TC14 LMPMI Symposium 2014
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David I. Serrano-Garcia, Yukitoshi Otani
Optical measurement techniques have become indispensable tools in many areas of science and engineering. The whole-field, non-contact and highly accurate measurement are among the principal features of these techniques. The purpose of this research is to analyze the case when the sample under study presents polarization properties, as retardance or diattenuation. The use of phase shifting modulated by polarization has the advantage of not requiring mechanical components, such as a piezoelectric transducer (PZT), to obtain the phase shifts. The main purpose of introducing polarization phase...
TC14 LMPMI Symposium 2014
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Takashi Nishikawa
This system is developed as a focus variation microscopic system with great versatility and high vertical resolution. Conventional focus variation microscopic systems cannot measure surface topography of smooth surfaces such as a glass surface because the surface has no texture to get effective point focus sharpness. This system can obtain very high point focus sharpness by operating a 3x3x3 voxel operator, we call ‘the Digital Stylus’, to fringe images which are generated by the two beam interferometric objective lens. Furthermore a new algorithm to decide the position of focal point, we...
TC14 LMPMI Symposium 2014
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Ryszard Jablonski
Nanotechnology approaching the sphere of quantum mechanics has a lot of limits connected with indirect definition of base, which should be directly related to physical constants and laws. It takes place also in measurements based on superposition of laser beams. Commonly, laser diffraction is considered to be a precise technique to measure dimensions of 3D objects, however, when required accuracy is on the level of 100nm the existing solutions do not fit to engineering applications. T. Young interpreted the diffraction phenomena as a result of interference of the geometrical wave propagating...
TC14 LMPMI Symposium 2014
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Li Menglin, Xie Wenfeng, Zhu Jingguo, Ren Jianfeng, Xiao Fang, Meng Zhe
Phase-shift range finder is to measure the phase-shift of the modulation wave during its propagation. The precision of traditional phase-shift range finder is limited by measurement rate and the modulation depth. Usually the modulation depth of laser diode decreases with the increase of modulation frequency which is crucial for high precision with sinusoidal modulation. A new phase-shift range finder with dual-frequency He-Ne laser is introduced. The error model is built in order to analyze the factors influencing the precision of phase-shift laser range finder. Two digital phase-shift...
TC14 LMPMI Symposium 2014
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Yao Huang, Zi Xue, He Yan Wang
In National Institute of Metrology, China (NIM), the Small Angle Measuring System which is based on sine principle, is developed as the national primary standard for the plane angle in the angular measuring range ±5°. The measurement uncertainty of this system is dominated by the accuracy of an Invar Angular Interferometer Optics. To calibrate this Invar Interferometer system, a series of known reference standards were given with multi-step method using a double-deck rotary table. The calibration got an uncertainty lower than 0.03 arcsec ( k = 2).
TC14 LMPMI Symposium 2014
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· 2014
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