11 research outputs found
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Body surface imaging
An embodiment of the invention may provide a portable, inexpensive two-view 3D stereo vision imaging system, which acquires a 3D surface model and dimensions of an object. The system may comprise front-side and back-side stereo imagers which each have a projector and at least two digital cameras to image the object from different perspectives. An embodiment may include a method for reconstructing an image of a human body from the data of a two-view body scanner by obtaining a front scan image data point set and a back scan image data point set. A smooth body image may be gained by processing the data point sets using the following steps: (1) data resampling; (2) initial mesh generation; (3) mesh simplification; and (4) mesh subdivision and optimization.Board of Regents, University of Texas Syste
Optical-fiber-based Mueller optical coherence tomography
An optical-fiber-based multichannel polarization-sensitive Mueller optical coherence tomography (OCT) system was built to acquire the Jones or Mueller matrix of a scattering medium, such as biological tissue. For the first time to our knowledge, fiber-based polarization-sensitive OCT was dynamically calibrated to eliminate the polarization distortion caused by the single-mode optical fiber in the sample arm, thereby overcoming a key technical impediment to the application of optical fibers in this technology. The round-trip Jones matrix of the sampling fiber was acquired from the reflecting surface of the sample for each depth scan (A scan) with our OCT system. A new rigorous algorithm was then used to retrieve the calibrated polarization properties of the sample. This algorithm was validated with experimental data. The skin of a rat was imaged with this fiber-based system
Optical-fiber-based Mueller optical coherence tomography
An optical-fiber-based multichannel polarization-sensitive Mueller optical coherence tomography (OCT) system was built to acquire the Jones or Mueller matrix of a scattering medium, such as biological tissue. For the first time to our knowledge, fiber-based polarization-sensitive OCT was dynamically calibrated to eliminate the polarization distortion caused by the single-mode optical fiber in the sample arm, thereby overcoming a key technical impediment to the application of optical fibers in this technology. The round-trip Jones matrix of the sampling fiber was acquired from the reflecting surface of the sample for each depth scan (A scan) with our OCT system. A new rigorous algorithm was then used to retrieve the calibrated polarization properties of the sample. This algorithm was validated with experimental data. The skin of a rat was imaged with this fiber-based system
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Development of a three-dimensional anthropometry system for human body composition assessment
textThe prevalence of obesity has made it necessary to develop a convenient, reliable and safe tool for timely assessing and monitoring this condition in public health. We suggest that three-dimensional (3D) anthropometry can provide a convenient, accommodating and comprehensive means to body composition assessment. A 3D anthropometry system based on stereo vision technology is developed. To make it more portable and affordable, the system is reduced to a two-stance design and only uses off-the-shelf components. The system is calibrated in two separate stages: camera calibration and 3D registration. The first stage is relatively complicated, but there is no need to repeat frequently. Therefore, only 3D registration is required when the system is transported. This property contributes to the portability and also reduces cost of maintenance. In this system, image acquisition can be completed in 200 ms, which is important in reducing artifacts caused by slight body movement. However, the computation in stereo vision is complex and intensive, and is still a challenge. A two-phase stereo matching algorithm is developed. In the first phase, the foreground is accurately segmented with the help of a predefined virtual interface, and a coarse disparity map is generated with block matching. In the second phase, local least squares matching is performed in combination with global optimization within a regularization framework, so as to ensure both accuracy and reliability. To make the 3D data more interpretable and manageable, it is essential to convert the raw 3D data to a surface model. For our system, a unique challenge is that there are large gaps in the data caused by occlusions. An effective surface reconstruction algorithm based on subdivision surface representation is developed. It has been verified that the algorithm is reliable in gap closing, accurate in representation, and efficient in data compression. To make the 3D anthropometry system ready for practical use, a body measurement system dedicated to body composition assessment is developed based on an earlier system that was designed for applications in apparel fitting. The functions of 3D measurement are enhanced by taking advantage of modern graphics hardware. The overall performance of the presented system has been evaluated on mannequins and human subjects. It has been shown that the measurements are highly repeatable. The feasibility of 3D anthropometry in body fat assessment has been demonstrated in comparison to air displacement plethysmography and bioimpedance analysis.Biomedical Engineerin
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System, method and apparatus for fiber sample preparation for image analysis
The present invention is an apparatus, system and method for preparing samples for analysis including a mechanical fiber cutting apparatus. The mechanical fiber cutting apparatus has two or more cutter blades under the control of a blade moving mechanism. A fiber chamber is positioned to receive the one or more cut fibers created by the cutting action of the two or more cutter blades. The pressurized gas source connected to the fiber chamber transfers the one or more cut fibers into a sample preparation housing. The one or more cut fibers are distributed randomly onto a sample slide within the sample preparation housing.Board of Regents, University of Texas Syste