578 results about "Dual energy" patented technology

A dual energy scanning densitometry system for imaging and measuring bone density maintains acceptable flux by adjusting the x-ray current or scan speed according to preceding scan line data. The amount of acceptable flux is maintained within limits modified by information about the region of the body being scanned so that different precisions may be maintained for different body regions. Scan speed and current may be controlled so that scan speed is maximized within the current limits. Essentially continuous flux control can be achieved.

The present invention relates to radiographic imaging apparatus for taking X-ray images of an object. In various two-panel radiographic imaging apparatus configurations, a front panel and back panel have substrates, arrays of signal sensing elements and readout devices, and passivation layers. The front and back panels have scintillating phosphor layers responsive to X-rays passing through an object produce light which illuminates the signal sensing elements to provide signals representing X-ray images. The X-ray apparatus has means for combining the signals of the X-ray images to produce a composite X-ray image. Furthermore, the composition and thickness of the scintillating phosphor layers are selected, relative to each other, to improve the diagnostic efficacy of the composite X-ray image. Alternatively, a radiographic imaging apparatus has a single panel having arrays of signal sensing elements and readout devices and scintillating phosphor layers that are disposed on both sides of a single substrate. The present invention further relates to various embodiments of indirect dual-screen DR flat-panel imager apparatus that provide single-exposure dual energy imaging.

A dual-energy x-ray imaging system searches a moving automobile for concealed objects. Dual energy operation is achieved by operating an x-ray source at a constant potential of 100 KV to 150 KV, and alternately switching between two beam filters. The first filter is an atomic element having a high k-edge energy, such as platinum, gold, mercury, thallium, lead, bismuth, and thorium, thereby providing a low-energy spectrum. The second filter provides a high-energy spectrum through beam hardening. The low and high energy beams passing through the automobile are received by an x-ray detector. These detected signals are processed by a digital computer to create a steel suppressed image through logarithmic subtraction. The intensity of the x-ray beam is adjusted as the reciprocal of the measured automobile speed, thereby achieving a consistent radiation level regardless of the automobile motion. Accordingly, this invention provides images of organic objects concealed within moving automobiles without the detritus effects of overlying steel and automobile movement.

Systems and methods for x-ray imaging a patient's breast in combinations of dual-energy, single-energy, mammography and tomosynthesis modes that facilitate screening for and diagnosis of breast abnormalities, particularly breast abnormalities characterized by abnormal vascularity.

The CT threat resolution system includes an primary EDS scanning process to identify threats and the nature of threats and a plurality of secondary CT scanning processes to resolve threats. The primary EDS scanning process and secondary CT scanning processes can be either separate machines or multiple processes within a single scanner. The secondary scanning process may utilizes dual energy scanning and/or high resolution scanning to resolve threats based upon the nature of the threat. An alarm indicates threats which cannot be resolved by the secondary CT scanning process for further operator investigation. Threats may be reviewed and resolved by an operator before the secondary CT scanning process.

A method of obtaining a computed tomography image of an object includes determining linear terms and non-linear beam hardening terms in a pair of line integral equations for dual-energy projection data from inserting average and difference from average attenuation terms, obtaining an initial solution of the line integral equation by setting the non-linear beam hardening terms to zero, and iteratively solving the line integral equations to obtain one line integral equations for each basis material. Attenuation by the first basis material corresponds to a photoelectric attenuation process, and attenuation by the second basis material corresponds to a Compton attenuation process. The line integral equations can be inverted by an inverse Radon procedure such as filtered backprojection to give images of each basis material. The images of each basis material can then be optionally combined to give monochromatic images, density and effective atomic number images, or photoelectric and Compton processes images.

A system for spectroscopic imaging of bodily tissue in which a scintillation screen and a charged coupled device (CCD) are used to accurately image selected tissue. Applications include the imaging of radionuclide distributions within the human body or the use of a dual energy source to provide a dual photon bone densitometry apparatus that uses stationary or scanning acquisition techniques. An x-ray source generates x-rays which pass through a region of a subject's body, forming an x-ray image which reaches the scintillation screen. The scintillation screen reradiates a spatial intensity pattern corresponding to the image, the pattern being detected by a CCD sensor. The image is digitized by the sensor and processed by a controller before being stored as an electronic image. A dual energy x-ray source that delivers two different energy levels provides quantitative information regarding the object being imaged using dual photon absorptiometry techniques. Dual scintillation screens can be used to simultaneously generate images of low-energy and high-energy x-ray patterns. Each image is directed onto an associated respective CCD or amorphous silicon detector to generate individual electronic representations of the separate images.

A system and method for creating a combined or mixed-energy image using both low- and high-energy CT data sets acquired using a dual-energy CT system. The low- and high-energy datasets are mixed using desired weighting factors to mimic a “single-energy” image. The low-energy dataset provides data with improved contrast enhancement, but with increased noise level. The high-energy dataset provides data with lower contrast enhancement, but with better noise properties. By combining the low- and high-energy datasets in accordance with the present method, the resulting mixed-energy images utilize the information of full dose of radiation used in the dual-energy scan. A plurality of weighting metrics can be selected, including patient size, dose partitioning, or image quality, to determine the desired weighting factors based on the weighting metrics. By selecting the proper weight factors, image noise can be reduced and/or the contrast to noise ratio can be increased in the mixed-energy image.

A method for reducing mis-registration during multiple energy scanning on computed tomographic (CT) imaging systems or multiple energy electron beam tomographic (EBT) systems includes scanning a portion of a patient including a cyclically moving body part using a multiple energy computed tomographic (CT) imaging system or multiple energy electron beam tomographic (EBT) system having at least two different energies, monitoring the cyclically moving body part, and gating the multiple energy CT imaging system or multiple energy EBT system in accordance with the monitored cyclically moving body part so that acquisitions are acquired at at least two different kVps. The data acquired at the different kVps are then utilized to generate material decomposition images of the cyclically moving body part.

A dual-energy x-ray source located a distance of one half of the maximum width of the subject from the subject emits a cone beam to a horizontal slit in an x-ray-blocking sheet, producing a fan beam that is chopped into a pencil beam by a rotating disk with radial slots. The pencil beam sweeps a subject, producing backscatter read by a plastic scintillator detector situated very close to and curved around the sides of the subject. The entire assembly translates vertically to produce a complete image of the subject. Pencil beam area is increased farther from the center by increasing the width of the slit toward both ends and increasing the width of the slots toward the outer end. High and low peak x-ray energies of 50 KeV or more and 30 KeV or less, respectively, enable differentiation between innocent and contraband materials that both contain low Z materials.

Fast kV-switching is a dual energy acquisition technique in computed tomography (CT) in which alternating views correspond to the low and high tube voltages. Its high temporal resolution and its suitability to a variety of source trajectories make it an attractive option for dual energy data acquisition. Its disadvantages include a one-view misregistration between the data for high and low voltages, the potentially poor spectrum separation due to the more-like a sine wave rather than the desired square wave in fast kV-switching, and the higher noise in the low voltage data because of the technical difficulty in swinging the tube current to counter the loss of x-ray production efficiency and loss of penetration at lower tube voltages. Despite the disadvantages, symmetric view matching according to the current invention substantially improves streaks and other artifacts due to the view misregistration, sufficient spectrum separation even in a sinusoidal waveform swinging between 80 kV and 135 kV, and contrast-to-noise for the simulated imaging task maximized at monochromatic energy of 75 keV.

A computer implemented method for joint image registration and reconstruction of a plurality of images includes providing the plurality of images, modeling the plurality of images, including reconstructing bone and soft-tissue in respective images of the plurality of images, performing a hierarchical free-form registration of models of the plurality of images to determine a jointly registered and reconstructed image with successive accuracy adjustment according to a registration error, and outputting the registered and reconstructed image.

For the purpose of providing an X-ray tomographic imaging apparatus for displaying a dual-energy image to facilitate diagnosis by an operator, an X-ray tomographic imaging apparatus (10) comprises: an image comparison information calculating section (24) for calculating image comparison information between said first-energy projection dataset (LD) or first-energy tomographic image (LT) and said second-energy projection dataset (HD) or second-energy tomographic image (HT); a region-of-interest defining section (23) for defining a region of interest; a weighting factor determining section (25-2) for determining a weighting factor for use in weighted subtraction processing between said first-energy projection dataset or first-energy tomographic image and said second-energy projection dataset or second-energy tomographic image, such that said image comparison information in said region of interest can be substantially eliminated by conducting said weighted subtraction processing; and a dual-energy image reconstructing section (22) for reconstructing a dual-energy image by conducting weighted subtraction processing between said first-energy projection dataset or first-energy tomographic image and said second-energy projection dataset or second-energy tomographic image used in said image comparison information calculating section, using a weighting factor determined at said weighting factor determining section.

A motor vehicle bumper that has enhanced energy absorption characteristics and that includes one or more unique geometry configurations that extend “softer” energy absorbing surfaces forward in the system while nesting more “rigid” energy absorbing surfaces more rearward only to come into effect when higher energy impacts are observed. The dual energy absorption may be achieved using a number of configurations and/or methods or a combination of several. In one or more embodiments, the wall thickness of the material used in the component or components may be varied, materials having different stiffness properties may be used, and/or geometries of different depth and section stiffness may be alternated across the bumper system.

The invention discloses a dual-energy X-ray phase-contrast imaging device and an implementation method thereof. The dual-energy X-ray phase-contrast imaging device comprises an X-ray apparatus, a source grating, a beam splitting grating, a sample chamber, an analysis grating and an X-ray detector along an optical path sequentially, wherein the X-ray apparatus is used for sending out X-rays; the source grating is used for dividing a large-focus X-ray source into a plurality of independent small-focus optical sources; the beam splitting grating is used for dividing the small-focus optical sources into a plurality of beams which irradiate a sample in the sample chamber, and a geometric projection is formed on the analysis grating; the sample chamber is used for holding and fixing the sample, and driving the sample to rotate at the same time; the analysis grating is used in cooperation with the beam splitting grating for forming moire fringes on the X-ray detector; the X-ray detector is used for obtaining and recording the moire fringes. When the dual-energy X-ray phase-contrast imaging device is utilized for dual-energy X-ray phase-contrast imaging, two selected energy values, namely V (high energy) and V (low energy) can be freely adjusted based on the actual situation, so that the usable range of dual-energy X-ray phase-contrast imaging can be widened.

A multi-energy polarization imaging method consisting of a multi-fusion, dual-rotating retarder/multiple-energy complete Mueller matrix-based polarimeter and dual-energy capabilities, has been invented. The term multifusion describes the use of several imaging functions altogether such as polarimetric imaging, dual-energy subtraction, multifocal imaging and other. By substracting polarimetric parameters such as degree of polarization, degree of linear polarization, degree of circular polarization, respectively, obtained with interrogation light beams of wavelengths λ₁ and λ₂, he system, enhanced imaging is obtained. The system includes a light source for illuminating a target with a first quantity of light having a first wavelength and a second quantity of light having a second wavelength, the first and second wavelengths being different. A polarization-state generator generates a polarization state for each of the first and second quantities of light, and includes a first polarizer through which the first and second quantities of light are transmitted before entering a first waveplate. A polarization-state receiver evaluates a resulting polarization state of the first and second quantities of light following illumination of the target, the polarization-state receiver including a second waveplate through which the first and second quantittes of light are transmitted before entering a second polarizer. An optical image-capture device captures a first image of the target illuminated by the first quantity of light and a second image of the target illuminated by the second quantity of light. A processing unit assigns a weighting factor to at least one of the first and second images and evaluates a weighted difference between the first and second images to generate a multi-energy image of the target.

Certain embodiments provide a radiation analysis system for material segmentation utilizing computed tomography (CT) scans. The radiation analysis system includes an input module configured to input dual energy data. The dual energy scanned data includes first data corresponding to a first parameter and second data corresponding to a second parameter for a given scanned volume. The radiation analysis system also includes a processor configured to generate a scatter plot based on the dual energy data. The first data corresponds to a first axis and the second data corresponds to a second axis. The processor is configured to identify at least one material type based on the scatter plot.

The present invention provides an X-ray CT apparatus capable of improving image quality of a dual energy image. The X-ray CT apparatus comprises an X-ray tube for applying X rays having a first energy spectrum and X rays having a second energy spectrum different from the first energy spectrum to a subject, an X-ray data acquisition unit for acquiring X-ray projection data of the first energy spectrum projected onto the subject and X-ray projection data of the second energy spectrum projected thereonto, dual energy image reconstructing unit for image-reconstructing tomographic images indicative of X-ray tube voltage-dependent information at X-ray absorption coefficients related to a distribution of atoms, based on the X-ray projection data of the first energy spectrum and the X-ray projection data of the second energy spectrum, and adjusting unit for adjusting conditions for the image reconstruction in order to optimize the tomographic images indicative of the X-ray tube voltage-dependent information.

Disclosed herein is a metal sorting device including an X-ray tube, a dual energy detector array, a microprocessor, and an air ejector array. The device senses the presence of samples in the x-ray sensing region and initiates identifying and sorting the samples. After identifying and classifying the category of a sample, at a specific time, the device activates an array of air ejectors located at specific positions in order to place the sample in the proper collection bin.