M. Vannier, D. M. Dye, R. Knapp, D. Gayou, N. Sammon, S. Dzik, R. L. Butterfield, J. Larson, W. Ellingson
Modern high resolution CT scanners can produce geometrically accurate sectional images of solid objects. Computer software has been developed to convert serial CT scans into a data base suitable for analysis using a Computer Aided Design / Computer-Aided Manufacturing (CAD/CAM) system.
{"title":"High Resolution Computed Tomography for Solid Modeling and Computer Aided Design","authors":"M. Vannier, D. M. Dye, R. Knapp, D. Gayou, N. Sammon, S. Dzik, R. L. Butterfield, J. Larson, W. Ellingson","doi":"10.1364/iact.1984.ma4","DOIUrl":"https://doi.org/10.1364/iact.1984.ma4","url":null,"abstract":"Modern high resolution CT scanners can produce geometrically accurate sectional images of solid objects. Computer software has been developed to convert serial CT scans into a data base suitable for analysis using a Computer Aided Design / Computer-Aided Manufacturing (CAD/CAM) system.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1984-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131590810","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}
{"title":"Tutorial on Algorithms for 3D Properties of Materials that Bend Rays","authors":"C. Vest","doi":"10.1364/iact.1984.mb1","DOIUrl":"https://doi.org/10.1364/iact.1984.mb1","url":null,"abstract":"Summary not available.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115542909","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}
The methods of conventional (X-ray) tomography have, in the past, been employed in a number of applications in optics such as combustion diagnostics [1] and con-destructive evaluation of strongly refracting objects such as optical fibers [2]. In these applications a laser is employed much in the same way as an X-ray source is employed in X-ray tomography [3]. For example, in combustion diagnostics [1] a narrow laser beam is made to scan through the object of interest and a photo detector records the transmitted light intensity thereby yielding a "projection" of the object’s attenuation profile. The algorithms of X-ray tomography such as ART or the filtered backprojection algorithm [3] can then reconstruct a cross-section of the attenuation profile from the measured data. In the case of strongly refracting objects [2] the goal is to reconstruct the object’s velocity profile from optical path length measurements of the transmitted optical field. These measurements yield a "generalized projection" of the real part of the object’s complex index of refraction profile. Although the reconstruction algorithms of X-ray tomography cannot be employed due to the refraction of the probing optical field, generalized reconstruction algorithms based on a ray model of the optical field have been developed [2] that can yield reconstructions of the real part of the index of refraction from the "generalized projections".
{"title":"Coherent Optical Tomography","authors":"A. Devaney","doi":"10.1364/iact.1984.tud3","DOIUrl":"https://doi.org/10.1364/iact.1984.tud3","url":null,"abstract":"The methods of conventional (X-ray) tomography have, in the past, been employed in a number of applications in optics such as combustion diagnostics [1] and con-destructive evaluation of strongly refracting objects such as optical fibers [2]. In these applications a laser is employed much in the same way as an X-ray source is employed in X-ray tomography [3]. For example, in combustion diagnostics [1] a narrow laser beam is made to scan through the object of interest and a photo detector records the transmitted light intensity thereby yielding a \"projection\" of the object’s attenuation profile. The algorithms of X-ray tomography such as ART or the filtered backprojection algorithm [3] can then reconstruct a cross-section of the attenuation profile from the measured data. In the case of strongly refracting objects [2] the goal is to reconstruct the object’s velocity profile from optical path length measurements of the transmitted optical field. These measurements yield a \"generalized projection\" of the real part of the object’s complex index of refraction profile. Although the reconstruction algorithms of X-ray tomography cannot be employed due to the refraction of the probing optical field, generalized reconstruction algorithms based on a ray model of the optical field have been developed [2] that can yield reconstructions of the real part of the index of refraction from the \"generalized projections\".","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"215 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123020917","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}
Noncontact and Nondestructive measurements in determing flame temperature distribution are currently under investigation.
测定火焰温度分布的非接触和非破坏性测量方法目前正在研究中。
{"title":"Flame Temperature Measurement by Infrared Ray Emission Computed Tomography","authors":"H. Uchiyama, M. Nakajima, S. Yuta","doi":"10.1364/iact.1984.mb2","DOIUrl":"https://doi.org/10.1364/iact.1984.mb2","url":null,"abstract":"Noncontact and Nondestructive measurements in determing flame temperature distribution are currently under investigation.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127877811","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}
Nuclear Magnetic Resonance (NMR) techniques and systems have been developed to provide spatial resolution, measurement localization and selective detection and measurement of solid and liquid materials having specific ranges and combinations of spin-lattice, T1, and spin-spin, T2, relaxation times. Spatial resolution and localization are achieved by use of gradient fields while multi-pulse methods have been developed to obtain T1, T2 selectivity. NMR systems utilizing Sensors based on the use of U-shaped magnets and flat, spiral-wound radiofrequency detection coils have been developed to make remote, spatially localized NMR measurements from a single surface. A schematic diagram of this approach is shown in Figure 1. The size, shape and location of the localized region from which NMR signals are obtained is determined by the magnitude and gradients of the magnetic fields. The localized region can be moved closer to, or farther away from, the sensor by varying the magnetic field strength. The NMR system incorporates an integral microcomputer for control of the data acquisition and signal processing, and includes a radiofrequency transmitter operating at 2 MHz capable of producing pulses of a controlled width and power up to 200 kW peak to insure optimum NMR detection over a specified remote region.
{"title":"Industrial Applications of Gradient Field NMR","authors":"J. D. King, G. Matzkanin, W. Rollwitz","doi":"10.1364/iact.1984.md4","DOIUrl":"https://doi.org/10.1364/iact.1984.md4","url":null,"abstract":"Nuclear Magnetic Resonance (NMR) techniques and systems have been developed to provide spatial resolution, measurement localization and selective detection and measurement of solid and liquid materials having specific ranges and combinations of spin-lattice, T1, and spin-spin, T2, relaxation times. Spatial resolution and localization are achieved by use of gradient fields while multi-pulse methods have been developed to obtain T1, T2 selectivity. NMR systems utilizing Sensors based on the use of U-shaped magnets and flat, spiral-wound radiofrequency detection coils have been developed to make remote, spatially localized NMR measurements from a single surface. A schematic diagram of this approach is shown in Figure 1. The size, shape and location of the localized region from which NMR signals are obtained is determined by the magnitude and gradients of the magnetic fields. The localized region can be moved closer to, or farther away from, the sensor by varying the magnetic field strength. The NMR system incorporates an integral microcomputer for control of the data acquisition and signal processing, and includes a radiofrequency transmitter operating at 2 MHz capable of producing pulses of a controlled width and power up to 200 kW peak to insure optimum NMR detection over a specified remote region.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127878505","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}
{"title":"Tutorial on Mathematical Foundations of Computed Tomography","authors":"Kennan T. Smith","doi":"10.1364/iact.1984.tuc2","DOIUrl":"https://doi.org/10.1364/iact.1984.tuc2","url":null,"abstract":"Summary not available","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125716122","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}
In computed tomography (CT) as well as other areas of digital image processing, a discrete representation of a function of two variables on a continuous domain is needed. One approach is to specify the values of the function on an equally spaced grid and interpolate for intermediate values. A more general approach Is to represent the function as a linear combination of basis functions [1,2]. Iterative CT algorithms, e.g., ART, require repeated evaluation of line or strip projection integrals over a trial object function (reconstruction). If the first representation is selected, then we must get interpolated values in order to perform the integration. The interpolation can be performed in a variety of ways; each way makes implicit use of a set of basis functions. If nearest-neighbor interpolation is chosen, the resulting set of basis functions are square pixels centered on the sample points. For bilinear interpolation we get a bilinear tent function and for band-limited interpolation we get a product of separable sine functions with zeros at all sample points but one.
{"title":"Some results on the use of local basis functions for reconstruction representation in computed tomography","authors":"G. W. Wecksung, K. Hanson","doi":"10.1364/iact.1984.tuc5","DOIUrl":"https://doi.org/10.1364/iact.1984.tuc5","url":null,"abstract":"In computed tomography (CT) as well as other areas of digital image processing, a discrete representation of a function of two variables on a continuous domain is needed. One approach is to specify the values of the function on an equally spaced grid and interpolate for intermediate values. A more general approach Is to represent the function as a linear combination of basis functions [1,2]. Iterative CT algorithms, e.g., ART, require repeated evaluation of line or strip projection integrals over a trial object function (reconstruction). If the first representation is selected, then we must get interpolated values in order to perform the integration. The interpolation can be performed in a variety of ways; each way makes implicit use of a set of basis functions. If nearest-neighbor interpolation is chosen, the resulting set of basis functions are square pixels centered on the sample points. For bilinear interpolation we get a bilinear tent function and for band-limited interpolation we get a product of separable sine functions with zeros at all sample points but one.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127755091","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}
{"title":"Tutorial on Iterative and Object-Dependent Algorithms","authors":"R. Rangayyan","doi":"10.1364/iact.1984.tua1","DOIUrl":"https://doi.org/10.1364/iact.1984.tua1","url":null,"abstract":"Summary not available.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132606589","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}
Although the tomographic reconstruction technique assumes that the projections correspond to sets of line integrals, the measurements are, in fact, made with beams having a finite width and height. This has important implications for the design of tomography systems. Artifacts may be generated by variations in the beam profile across the slice [1]. Furthermore, the spatial resolution that can be achieved with a given beam geometry is limited to the full-width at half-maximum (FWHM) of the beam profile [1]. (Image restoration can improve spatial resolution but only at the expense of contrast discrimination [2].) Therefore, a detailed knowledge of the spatial response associated with various beam geometries is essential for the design of tomography scanners.
{"title":"The Spatial Response of Source-Collimator-Detector Systems","authors":"T. Taylor","doi":"10.1364/iact.1984.mc4","DOIUrl":"https://doi.org/10.1364/iact.1984.mc4","url":null,"abstract":"Although the tomographic reconstruction technique assumes that the projections correspond to sets of line integrals, the measurements are, in fact, made with beams having a finite width and height. This has important implications for the design of tomography systems. Artifacts may be generated by variations in the beam profile across the slice [1]. Furthermore, the spatial resolution that can be achieved with a given beam geometry is limited to the full-width at half-maximum (FWHM) of the beam profile [1]. (Image restoration can improve spatial resolution but only at the expense of contrast discrimination [2].) Therefore, a detailed knowledge of the spatial response associated with various beam geometries is essential for the design of tomography scanners.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130598590","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}
Monolithic ceramic materials such as SiC, Si3N4, Al2O3, and ceramic-ceramic composite materials such as SiC-reinforced Al2O3, SiC-SiC, and SiC-reinforced glass are emerging as important engineering structural materials. A major problem with using ceramic materials in engineering structures is the lack of reliability. The low reliability is caused by unreliable mechanical properties which are usually caused by internal flaws such as cracks and pore clusters in monolithic materials and clustering of whiskers and whisker stratification in composite materials. Design methodology with brittle solids is in its infancy and nondestructive examination methods which can be used to detect the load limiting flaws are necessary before the ceramic materials can be reliably used.
{"title":"Application of Tomographic Imaging to Structural Ceramics: Green-State Monolithics and Ceramic-Ceramic Composites*","authors":"W. Ellingson, M. Vannier","doi":"10.1364/iact.1984.mb6","DOIUrl":"https://doi.org/10.1364/iact.1984.mb6","url":null,"abstract":"Monolithic ceramic materials such as SiC, Si3N4, Al2O3, and ceramic-ceramic composite materials such as SiC-reinforced Al2O3, SiC-SiC, and SiC-reinforced glass are emerging as important engineering structural materials. A major problem with using ceramic materials in engineering structures is the lack of reliability. The low reliability is caused by unreliable mechanical properties which are usually caused by internal flaws such as cracks and pore clusters in monolithic materials and clustering of whiskers and whisker stratification in composite materials. Design methodology with brittle solids is in its infancy and nondestructive examination methods which can be used to detect the load limiting flaws are necessary before the ceramic materials can be reliably used.","PeriodicalId":133192,"journal":{"name":"Topical Meeting on Industrial Applications of Computed Tomography and NMR Imaging","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129907624","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}
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