Filter Patents (Class 378/156)
  • Publication number: 20020051516
    Abstract: The invention concerns an X-ray examination device, including an X-ray source and an X-ray detector, for forming an X-ray image of an object, an X-ray filter, arranged between the X-ray source and the X-ray detector, and adjusting means, connected to the X-ray filter for adjusting it. The adjusting means comprise a graphics device, cursor control means for defining a region of interest in an image of said object, displayed on said graphics device, and processing means, connected to the X-ray filter, for calculating the region of interest and adjusting the filter accordingly. The X-ray filter includes filter elements having an X-ray absorptivity which can be adjusted by controlling a quantity of X-ray absorbing liquid within the individual filter elements. The filter elements are capillary tubes, and means for applying electric voltages to the individual capillary tubes are provided for controlling the quantity of X-ray absorbing liquid therein.
    Type: Application
    Filed: September 18, 2001
    Publication date: May 2, 2002
    Inventors: Paul Zwart, Robert Derk Jan Hendrik Hofsink
  • Patent number: 6381304
    Abstract: A compensator filter is used to adjust the radiation therapy beam of a linear accelerator device to compensate for tissue that may have been removed surgically. The compensator filter is formed of a plastic material having a density of about one to two times that of the patient's tissue, and is disposed in the filter tray of the linear accelerator for selectively attenuating the radiotherapy beam to compensate for the missing tissue. Preferably, the filter can be made from a blank cast of polyurethane filled with glass microspheres, such that the filter is substantially free of heavy metal substances and toxic materials. The blank can be milled in a compensator filter milling machine of the type that is found in radiotherapy clinics.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: April 30, 2002
    Assignee: S&S X-Ray Products, Inc.
    Inventors: Norman A. Shoenfeld, Fred Sopenoff
  • Patent number: 6370228
    Abstract: An X-ray filter comprises an array of filter elements (5) an control circuit, the control circuit comprising an array of switching devices (33) provided on a common substrate (52), a switching device (33) being provided for each filter element for switching a control signal to the respective filter element. An output terminal of each switching device is provided with an external connection portion (54) located at the respective switching device. An array of external connection portions (54) is thus provided over the array of switching devices (33). The connection portions are then bonded to a connection block of the array of filter elements. This avoids the need to use edge connections of the substrate (52), and provides a secure mechanical and electrical connection between the control circuit and the filter array.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: April 9, 2002
    Assignee: U.S. Philips Corporation
    Inventors: Alan J. Mockler, Menno W. Prins, Johannes W. Weekamp
  • Patent number: 6366636
    Abstract: An X-ray sensor signal processor including capacitors 114 for removing DC components (dark currents) from output signals of semiconductor sensors 21 to 2n detecting pulse-like X-rays passed through an object, and integrators (each of which is constituted by a combination of an operational amplifier 115, a resistor 116 and a capacitor 117) for integrating the output signals of the X-ray sensors after removal of the DC components by the capacitors 114. By this, a value proportional to the average number of photons in X-rays can be obtained even in the case where a small number of incident photons are given, and an X-ray CT system using the X-ray sensor signal processor.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: April 2, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Kamimura, Shigeru Izumi, Hiroshi Kitaguchi, Atsushi Yamagoshi, Katsutoshi Satoh
  • Patent number: 6359969
    Abstract: An apparatus, suited, for example, for extreme ultraviolet lithography, includes a radiation source and a processing organ for processing the radiation from the radiation source. Between the radiation source and the processing organ a filter is placed which, in the radial direction from the radiation source, comprises a plurality of foils or plates.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: March 19, 2002
    Assignee: Stichting voor de Technische Wetenschappen
    Inventor: Leonid Shmaenok
  • Patent number: 6339717
    Abstract: A medical examination system, particularly a magnetic resonance system, has a host computer unit, a control computer unit and an image computer unit. The control computer unit is realized in the form of at least one insert card that is arranged in a commercially obtainable personal computer that contains the host computer unit.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: January 15, 2002
    Assignee: Siemens Aktiengesellschaft
    Inventors: Rudi Baumgartl, Robert Krieg, Georg Pirkl, Markus Vester
  • Patent number: 6333965
    Abstract: An X-ray examination apparatus includes an X-ray source with a brightness control signal input, an X-ray image device for providing an X-ray image of an object to be imaged, X-ray absorption means between the X-ray source and the X-ray image device, a brightness control system coupled to the X-ray image device and the brightness control signal input in order to derive a brightness control signal from the X-ray image, and a detection means which is coupled between the X-ray image device and the brightness control signal input in order to exclude a degree of detected absorption from said brightness control signal caused by the absorption means present in the X-ray image. Direct radiation and absorption means (such as filters) in the detected absorption range in a histogram of pixels of the X-ray image are automatically excluded from the brightness control which is thus improved.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: December 25, 2001
    Assignee: U. S. Philips Corporation
    Inventor: Arnoldus P. L. Van Berkel
  • Publication number: 20010053200
    Abstract: When X-rays are projected to an X-ray sensor through a grid, a pitch of the grid has a relationship such that a length of multiplying an odd number to a half pitch of a projection image is equal to a pitch of detection pixels of the X-ray sensor. X-rays passing through a sample to be measured via the grid are detected by the X-ray sensor. Levels of the detected X-ray detection signals are inputted into an operation process portion and subjected to an equalizing process for every even number detection pixel group continuously lined up in a pitch direction of the grid, i.e. with a combination of a high value and a low value of the levels of the X-ray detection signals, as a unit. As a result, irregularities of the levels of the X-ray detection signals can be corrected, and moires generated on an output screen of an image display portion can be removed.
    Type: Application
    Filed: May 24, 2001
    Publication date: December 20, 2001
    Applicant: SHIMADZU CORPORATION
    Inventor: Naoyuki Hori
  • Publication number: 20010043670
    Abstract: An X-ray apparatus with an X-ray source for producing a beam of X-rays, an X-ray detector for detecting the beam, and an X-ray filter with filter elements which is arranged between the X-ray source and the X-ray detector so as to attenuate the X-ray beam in each independent filter element individually. Each filter element can receive a liquid having electrically conducting properties and X-ray absorbing properties, the value of the X-ray absorption of the filter element being dependent on the level of the X-ray absorbing liquid in the filter element. Each filter element includes a first electrode (23) which is located in the wall of the filter element and on top of the substrate layer (38) in order to apply an electric potential to the wall of the filter element. A second electric potential is applied to the liquid via a second electrode.
    Type: Application
    Filed: February 2, 2001
    Publication date: November 22, 2001
    Inventor: Menno Willem Jose Prins
  • Patent number: 6320938
    Abstract: A shield is placed on a patient's body over a secondary organ adjacent a target organ. The shield is partially transparent to x-ray radiation. A CT scan of the target organ is conducted according to conventional protocols and technical parameters. No artifacts are formed in the diagnostic portion of the CT image and there is no degradation of the diagnostic portion of the CT image. A reduction of between about 40% and about 60% in the radiation dose of the secondary organ as compared to the same CT scan made without the shield is achieved.
    Type: Grant
    Filed: October 28, 1998
    Date of Patent: November 20, 2001
    Assignee: F & L Medical Products
    Inventor: Kenneth D. Hopper
  • Publication number: 20010040938
    Abstract: An X-ray apparatus is equipped with an X-ray filter having adjustable absorption properties in order to reduce the dynamic range of an X-ray image. The filter includes a matrix of filter elements 13, 13′, 13″ in which a level of an X-ray absorption liquid can be varied. The amount of the X-ray absorption liquid within an individual filter element determines the value of the X-ray absorption within this filter element. It is necessary that the resultant amount of the X-ray absorption liquid within each filter element is reproducible. Such an X-ray filter (12) is mounted near the X-ray source and is rotated together with the gantry when an X-ray image is required with some angulation with respect to an object. When the X-ray filter is angled (&bgr;) with respect to the vertical direction (g), the hydrostatic pressure within filter elements varies with respect to the calibrated state and the resultant amount of the X-ray absorption liquid is not reproducible.
    Type: Application
    Filed: April 12, 2001
    Publication date: November 15, 2001
    Inventor: Menno Willem Jose Prins
  • Patent number: 6307918
    Abstract: The present invention, in one form, is an imaging system which, in one embodiment, utilizes a filter assembly including a plurality of filter portions for altering the intensity and quality of an x-ray beam. Specifically, in one embodiment, by positioning the filter assembly so that the x-ray beam is filtered by the first portion of the filter assembly, the x-ray beam is altered to perform a body portion scan. By positioning the filter assembly to the second portion, the x-ray beam is altered to perform a head portion scan.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: October 23, 2001
    Assignee: General Electric Company
    Inventors: Thomas L. Toth, Carmine F. Vara, Willi W. Hampel
  • Patent number: 6298117
    Abstract: Methods and apparatus for dose reduction in a computed tomography (CT) system are described. In one embodiment, the CT system includes a pre-patient collimator and a configurable multislice detector array. The pre-patient collimator includes a plurality of eccentric cams and a filtration device for altering the x-ray beam radiated from a x-ray source. The eccentric cams are positioned to collimate the x-ray beam and may be independently positioned to provide z-axis correction of the x-ray beam. The filtration device includes a plurality of filters for altering the x-ray beam. In operation, an operator selects the type of test and the quantity and thickness of the slices. After altering the detector and collimator configuration, slice data for each slice is gathered.
    Type: Grant
    Filed: October 20, 2000
    Date of Patent: October 2, 2001
    Assignee: General Electric Company
    Inventors: Willi W. Hampel, Russell W. Hum, Carmine F. Vara, Jr., Steven J. Woloschek
  • Publication number: 20010022832
    Abstract: An X-ray apparatus with an X-ray source for producing a beam of X-rays, an X-ray detector for detecting the beam, and an X-ray filter with filter elements which is arranged between the X-ray source and the X-ray detector so as to attenuate the X-ray beam in each independent filter element individually. Each filter element (13) can receive a liquid (22) which is electrically conductive and X-ray absorbing, and is supplied via a transport channel (20), the X-ray absorptivity of each filter element being discretely adjustable by step-wise adjustment of the level of the liquid (22) in each filter element. Each filter element includes a first electrode (23) which is located in the wall of the filter element, on top of a substrate layer (38), in order to apply an electric potential to the wall of the filter element. A second electric potential is applied to the liquid (22) via a second electrode (29).
    Type: Application
    Filed: February 2, 2001
    Publication date: September 20, 2001
    Inventors: Menno Willem Jose Prins, Edward Willem Albert Young, Jeroen Van Velzen, Brian Kenneth Herbert
  • Patent number: 6289081
    Abstract: The invention relates to a method of manufacturing a filter which includes a number of ducts formed by a number of deformable foils. The foils have electrically insulating outer sides, with electrically conductive bands which are separated from one another by electrically insulating bands. The electrically conductive bands on a first outer side of the foil are arranged so as to be offset relative to the electrically conductive bands on the second outer side of the foil. The foils are stacked. The oppositely situated electrically insulating bands of the oppositely situated foils are interconnected. The foils are ultimately moved away from one another in a direction transversely of the foils in order to form the ducts between the interconnected foils. At least one detached, electrically insulating section is situated in a prolongation of at least one electrically conductive band and is not connected to an oppositely situated foil.
    Type: Grant
    Filed: October 5, 2000
    Date of Patent: September 11, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Johannus Wilhelmus Weekamp, Jacobus Bernardus Giesbers, Bartholomeus Peter Hendricus Van Nunen, Adrainus Cornelius Van Kasteren, Menno Willem Jose Prins
  • Patent number: 6275568
    Abstract: The invention relates to an X-ray apparatus which includes an adjustable X-ray filter. In order to adjust an intensity profile of the X-ray beam, an X-ray absorbing liquid is transported to filter elements of the X-ray filter. Such transport is susceptible to gravitational forces which lead to an irregular hydrostatic pressure distribution in the X-ray filter. In order to reduce the effects of the gravitational forces on the transport of the X-ray absorbing liquid, the duct connecting the filter elements to the reservoir is subdivided into sub-ducts and the reservoir is subdivided into chambers, each chamber being connected to at least one sub-duct. The X-ray apparatus also includes means for keeping the sub-ducts aligned with a horizontal plane.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: August 14, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Menno W. J. Prins, Johannus W. Weekamp, Jacobus B. Giesbers, Michel C. J. M. Vissenberg, Coenraad A. A. M. Vugts
  • Patent number: 6269147
    Abstract: An X-ray examination apparatus comprises an X-ray source, an X-ray detector (3) and an X-ray filter arranged between the X-ray source and the X-ray detector. The X-ray filter comprises a plurality of filter elements each comprising a vessel containing an X-ray absorbing liquid, the liquid level in each vessel determining the X-ray absorptivity of the respective filter element. Control means is provided for applying electric voltages to the individual filter elements to change the liquid levels within an adjust time period. The control means is arranged to apply a respective control voltage to each individual filter element a repeat number of times within the adjust time period, the repeat number being selected so as substantially to maximize the rate of change of liquid level of the filter elements. This enables patient examination times to be reduced, by reducing the times between sequential images.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: July 31, 2001
    Assignee: U.S. Philips Corporation
    Inventor: Martin J. Powell
  • Patent number: 6252939
    Abstract: The X-ray examination apparatus includes an X-ray source, an X-ray detector and an X-ray filter which is located between the X-ray source and the X-ray detector. The X-ray filter includes elements, notably capillary tubes, and the X-ray absorptivity of separate filter elements is adjustable by adjustment of a quantity of X-ray absorbing liquid in the respective filter elements. The quantity of X-ray absorbing liquid in the individual filter elements is adjusted by way of electric voltages applied to the individual filter elements. A control system is provided to apply the electric voltages selectively to the individual filter elements. The control system includes voltage lines and switching elements which electrically couple the filter elements to an electric voltage source. The filter elements are formed by spaces between corrugated plates or parallel plates provided with separating members, such as protrusions which extend transversely of the plates. The voltage lines are disposed on the plates.
    Type: Grant
    Filed: November 16, 1999
    Date of Patent: June 26, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Edward W. A. Young, Menno W. J. Prins, Johannes W. Weekamp, Jacobus B. Giesbers, Petrus W. J. Linders, Andreas C. M. Van Nes
  • Patent number: 6226355
    Abstract: The invention relates to an X-ray examination apparatus for forming X-ray images of an object. An X-ray examination apparatus of this kind includes an X-ray source, an X-ray filter for adjusting the two-dimensional distribution of an X-ray beam to be generated on the object and an X-ray detector. The X-ray filter includes capillary tubes whose inner sides are provided with an electrically conductive layer and one end of which communicates with a reservoir containing an X-ray absorbing liquid. For each capillary tube the quantity of X-ray-absorbing liquid can be adjusted by way of an electric voltage applied across the inner side of the capillary tube and the X-ray absorbing liquid. The X-ray filter is arranged between the object and the X-ray source, the tubes of the X-ray filter being arranged such that the tubes of the X-ray filter are arranged such that lines through all longitudinal axes of the tubes are intersecting lines extending through the X-ray source via the X-ray filter to the X-ray detector.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: May 1, 2001
    Assignee: U.S. Philips Corporation
    Inventor: Menno W. J. Prins
  • Patent number: 6201852
    Abstract: A variable attenuation apparatus for use with a radiation-blocking liquid and a radiation source having an attenuation chamber capable of containing a layer of the radiation-blocking liquid and an adjustment device for selectively metering the thickness of the layer of the radiation-blocking liquid, whereby changes in the thickness of the layer alter the radiation transmitted through the attenuation chamber. In one embodiment, an adjustment device includes a reservoir for holding the radiation-blocking liquid and a siphon connection device for allowing the transfer of the radiation-blocking liquid between the reservoir and the attenuation chamber, wherein the thickness of the layer in the attenuation chamber varies in response to changes in elevation of said reservoir, so that an increase in the thickness of the layer causes a drop in the radiation transmitted through the attenuation chamber.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: March 13, 2001
    Assignee: University of Medicine & Denistry of New Jersey
    Inventors: Sreekrishna Murty Goddu, Roger W. Howell, Dandamudi V. Rao
  • Patent number: 6188749
    Abstract: An X-ray examination apparatus (1), including an X-ray source (2) and an X-ray detector (5), is provided with an X-ray filter (6) which is arranged between the X-ray source and the X-ray detector. The X-ray filter (6) includes a plurality of filter elements (7) whose X-ray absorptivity can be adjusted by adjustment of a quantity of X-ray absorbing liquid (14) within the individual filter elements; a first end of individual filter elements communicates with the X-ray absorbing liquid whereas a second end communicates with an X-ray transparent liquid (12). The X-ray filter is preferably provided with a pressure control system for independent control of the liquid pressure in individual row ducts (11) and individual column ducts (13). Individual filter elements are preferably provided with a piston for separating the X-ray absorbing liquid from the X-ray transparent liquid.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: February 13, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Christoph Schiller, Mark A. De Samber, Lambertus G. J. Fokkink
  • Patent number: 6173039
    Abstract: Methods and apparatus for dose reduction in a computed tomography (CT) system are described. In one embodiment, the CT system includes a pre-patient collimator and a configurable multislice detector array. The pre-patient collimator includes a plurality of eccentric cams and a filtration device for altering the x-ray beam radiated from a x-ray source. The eccentric cams are positioned to collimate the x-ray beam and may be independently positioned to provide z-axis correction of the x-ray beam. The filtration device includes a plurality of filters for altering the x-ray beam. In operation, an operator selects the type of test and the quantity and thickness of the slices. After altering the detector and collimator configuration, slice data for each slice is gathered.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: January 9, 2001
    Assignee: General Electric Company
    Inventors: Willi W. Hampel, Russell W. Hum, Carmine F. Vara, Jr., Steven J. Woloschek
  • Patent number: 6157703
    Abstract: An x-ray beam hardening filter is disclosed. The x-ray beam hardening filter comprises a support member and a beam hardening sheet, the beam hardening sheet having a multidimensional array of regularly spaced apertures. The apertures are configured to have an x-ray transmissive quality. An actuator, engaging the support member, is capable of moving the multidimensional array of apertures into or out of a path of an x-ray beam, thereby selectively introducing varying levels of x-ray energy filtration. In one embodiment, multiple layers of beam hardening sheets are added to the x-ray beam hardening filter to create additional levels of x-ray energy filtration. Advantages of the x-ray beam hardening filter include the relatively small distance the x-ray beam hardening filter must move in order to absorb the incident x-ray beam, the ability to introduce varying levels of x-ray filtration, and the compact structure of the x-ray beam hardening filter.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: December 5, 2000
    Assignee: Cardiac Mariners, Inc.
    Inventors: Edward G. Solomon, Giovanni Pastrone
  • Patent number: 6148062
    Abstract: A filter having compensating plates, each having a first plate element which can be moved translationally with respect to a frame and a second plate element which can be moved relative to the first plate element so that, when the plates are in an active position, the thickness of absorbent material through which the X-ray beam passes is constant.
    Type: Grant
    Filed: November 2, 1998
    Date of Patent: November 14, 2000
    Assignee: GE Medical Systems, S.A.
    Inventor: Rene Romeas
  • Patent number: 6118854
    Abstract: An x-ray beam hardening filter and method for making the same is disclosed. According to an embodiment, the method comprises etching a plurality of regularly spaced pits into a surface area of a sheet having an x-ray beam hardening quality, aligning the sheet to a support member and bonding the sheet to the support member. An x-ray beam hardening filter can be made and used which is not only compact and useful in diagnostic x-ray imaging, but which is capable of shaping an x-ray energy spectrum envelope in a highly controllable manner.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: September 12, 2000
    Assignee: Cardiac Mariners, Inc.
    Inventors: Edward G. Solomon, Giovanni Pastrone
  • Patent number: 6118855
    Abstract: X-ray examination apparatus including a filter An X-ray examination apparatus (1) includes an X-ray source (2), an X-ray detector (5) and an X-ray filter (6). The X-ray filter (6) is arranged between the X-ray source and the X-ray detector. The X-ray filter (6) includes a plurality of filter elements (7) whose X-ray absorptivity can be adjusted by adjusting a quantity of X-ray absorbing liquid (30) present in individual filter elements (7). The filter elements are formed by substantially parallel plates (8), respective plates being provided with separating members (10) which project approximately transversely from the plane of such a plate. The filter elements are formed notably by parallel corrugated plates or by parallel plates provided with partitions extending transversely from the plates.
    Type: Grant
    Filed: May 21, 1998
    Date of Patent: September 12, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Wilhelmus J. J. Welters, Edward W. A. Young
  • Patent number: 6108403
    Abstract: An object (22) is positioned on a patient support (25) between an x-ray source (10) and an x-ray detector assembly (15). The x-ray source (10) is selectively activated to transmit an x-ray beam (20) through an imaging region (32) to the x-ray detector assembly (15). Positioning of the object (22) on the patient support (25) is such that a gap 33 exists in the imaging region (32) through which x-rays may pass unattenuated. An x-ray equalization filter (30) is introduced into the gap 33 and substantially conforms to its shape. The equalization filter (30) comprises a fluid medium disposed in a flexible receptacle. The fluid medium contains x-ray attenuating material suspended in a gel base. Placement of the equalization filter (30) in the gap reduces the number of unattenuated x-rays reaching the x-ray detector assembly (15) thereby enhancing image quality.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: August 22, 2000
    Assignee: Picker International, Inc.
    Inventors: Virgil N. Cooper, III, Zhongmin Lin
  • Patent number: 6094474
    Abstract: The device is used for compensating a hyper transparency area due to air inside or outside an organ while using a gantry mounting radiography apparatus with digital subtraction (DSA). The device comprises compensating filters and a supporting assembly for connecting the filters in front of the X-ray source. Each filter extends in a filter plane while the organ defines a median plane in which the rotation axis of the arms of the apparatus is substantially lying. The supporting assembly is designed to keep the filter in front of the X-ray source and in registry with the X-ray source and the hyper transparency area while keeping the filter plane parallel to the reference plane during rotation of the arms. Unlike existing X-ray compensating devices which are stationary, the present invention automatically sets itself for radiography of different views in function of the rotation of the arms of the apparatus.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: July 25, 2000
    Assignee: Octostop, Inc.
    Inventor: Jean A. Vezina
  • Patent number: 6087672
    Abstract: A charged particle beam irradiation system includes a beam spreading device, a ridge filter, a range shifter, a collimator, and a bolus. Further, on a supporting plate in the ridge filter, a plurality of ridge components are arranged, and shielding elements are attached at the top parts of a part of the plurality of the ridge components.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: July 11, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Koji Matsuda, Hiroshi Akiyama, Kazuo Hiramoto
  • Patent number: 6061426
    Abstract: An X-ray examination apparatus includes an X-ray source (1) for emitting X-rays. An object to be radiologically examined is arranged in an examination space. An X-ray detector (2) derives an image signal, for example an electronic video signal, from an X-ray image of the object. An X-ray filter locally attenuates the X-rays partly. The X-ray filter is arranged between the X-ray source and the X-ray detector and the X-ray filter is provided with filter elements whose X-ray absorptivity can be adjusted on the basis of an amount of X-ray absorbing liquid present within the individual filter elements.The X-ray examination apparatus includes an X-ray collimator for locally intercepting the X-rays. The X-ray collimator is arranged between the X-ray source and the examination space and is provided with collimator elements which can be switched between an X-ray transmitting state and an X-ray intercepting state.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: May 9, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Petrus W. J. Linders, Herman Stegehuis, Wilhelmus J. J. Welters, Nicolaas P. Willard, Lambertus G. J. Fokkink
  • Patent number: 6021175
    Abstract: An x-ray filter is used to permit higher intensity x-ray exposure to the upper thoracic spine while maintaining a normal level of x-ray exposure to the cervical spine. The resulting x-ray image allows a viewer to count the seven cervical vertebrae in order to identify the position of the first and second thoracic vertebrae. The filter is formed by a pair or mating blocks of x-ray absorbing material. The filter has a first region for absorbing x-ray radiation to decrease exposure of the cervical spine and has a second region with a V-shaped opening which allows higher x-ray transmission to the thoracic spine while reducing exposure on areas adjacent to the thoracic spine. The filter is formed by two shaped filter blocks which fit together to create the first and second regions. The edges of the filter blocks which form the V-shaped opening are beveled to create a generally trapezoidal exposure region which is aligned with the upper thoracic spine.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: February 1, 2000
    Inventor: Daniel J. Ferlic
  • Patent number: 6014423
    Abstract: An x-ray reflecting system comprising a plurality of x-ray reflectors, wherein the x-ray reflectors are coupled together to form a Kirkpatrick-Baez side-by-side system of multiple corners and may include multi-layer or graded-d multi-layer Bragg x-ray reflective surfaces.
    Type: Grant
    Filed: February 19, 1998
    Date of Patent: January 11, 2000
    Assignee: OSMIC, Inc.
    Inventors: George Gutman, Licai Jiang, Boris Verman
  • Patent number: 5965065
    Abstract: There is a need in the field of x-ray optics for an oxygen-free polymeric filter. This is because the mass absorption coefficient of oxygen is greater than that of carbon at every energy in the soft x-ray region except for a narrow band between the oxygen k-edge at 543.1 eV and the carbon k-edge at 284.2 eV. This band of frequencies is known as the "water window." The present invention is a method of filtering x-rays with the use of a freestanding, thin film of a polymer, metal-polymer composite, mesh-supported polymer film, or mesh-supported metal-polymer composite where the polymeric component of the filter is a PBI or a PPQ. In accordance with the present invention, the soft x-ray transmission of a 2500 angstrom polybenzimidazole film was measured as 3 to 5% more transmissive than either the polyimide DuPont 2610D or the polycarbonate GE Lexan.
    Type: Grant
    Filed: March 17, 1997
    Date of Patent: October 12, 1999
    Inventor: Stephen Forbes Powell
  • Patent number: 5966426
    Abstract: An X-ray examination apparatus (1) is provided with an X-ray source (2) and an X-ray detector (5) wherebetween there is arranged an X-ray filter (6) which includes filter elements (7) whose X-ray absorptivity can be adjusted by controlling the quantity of X-ray absorbing liquid (31) in individual filter elements (7). The filter elements (7) are formed by spaces between electrically conductive tracks (9) provided on parallel plates (8). The parallel plates are arranged in a reservoir (31) for the X-ray absorbing liquid. The liquid level in the vicinity of an electrically conductive track is controlled on the basis of an electric voltage applied to the relevant electrically conductive track (9).
    Type: Grant
    Filed: November 5, 1997
    Date of Patent: October 12, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Johannes Marra, Wilhelmus J. J. Welters
  • Patent number: 5923724
    Abstract: In a medical X-ray diagnostic installation and a method for operating same, an X-ray source has a filter means optionally introducible into its beam path and emits X-rays which strike a detector having individual pixel elements and which generates image signals pixel-by-pixel dependent on the received radiation. The detector is followed by a signal processing chain which includes processing meansfor image generation and output, first and only image exposure of the examination subject initially ensues without the filter means introduced into the beam path, after which the image signals obtained from one or more picture element regions of the received image are processed pixel-by-pixel for generating a calculated image corresponding to the image of those regions which would be obtained with the filter means in the beam path, using signals which identify a position of the filter means in the beam path.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: July 13, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Peter Soukal
  • Patent number: 5881127
    Abstract: The present invention provides for an improved automatic x-ray beam equalizer. By analyzing an initial low dosage x-ray image of an object, an attenuation pattern can be calculated. An equalization pattern, generated from the attenuation pattern, can then be created in a mask and placed in the path of a full x-ray beam scan using a stepper motor assembly in order to properly attenuate the x-ray signal and create a clearer x-ray image of the object.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: March 9, 1999
    Assignee: The Regents of the University of California
    Inventors: Sabee Molloi, Jerry Tang
  • Patent number: 5841834
    Abstract: A filter arrangement in a radiography apparatus in order to define the intensity of the radiation beam incident upon the object. To the movable filter part in front of the radiation source (2) there is coupled an electric circuit element, for example a potentiometer, from which the signal is applied further to a row (8) of light-emitting diodes in the vicinity of the object to be radiographed, for example the patient's head (7). When the filter is moved, the electric signal controls the light-emitting diodes so that the light-emitting diodes which become illuminated in the row will indicate the boundary of the filtered radiation beam at a given time.
    Type: Grant
    Filed: November 29, 1996
    Date of Patent: November 24, 1998
    Assignee: Orion-Yhtyma OY
    Inventor: Esa Pekka Suuronen
  • Patent number: 5778046
    Abstract: The present invention provides for an improved automatic x-ray beam equalizer. By analyzing an initial low dosage x-ray image of an object, an attenuation pattern can be calculated. An equalization pattern, generated from the attenuation pattern, can then be created in a mask and placed in the path of a full x-ray beam scan in order to properly attenuate the x-ray signal and create a clearer x-ray image of the object.
    Type: Grant
    Filed: January 19, 1996
    Date of Patent: July 7, 1998
    Assignee: The Regents of the University of California
    Inventors: Sabee Molloi, Jerry Tang
  • Patent number: 5768340
    Abstract: An X-ray examination apparatus includes an X-ray filter with a plurality of filter elements for locally attenuating the X-ray beam. The X-ray absorptivity of each filter element is controlled by the amount of X-ray absorbing liquid with which the filter element is filled. The filling of filter elements is controlled by a voltage. The X-ray absorbing liquid contains a suspension of very small X-ray absorbing particles.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: June 16, 1998
    Assignee: U.S. Philips Corporation
    Inventors: Peter E. E. Geittner, Petrus W. J. Linders, Hans-Jurgen Lydtin
  • Patent number: 5751786
    Abstract: An X-ray examination apparatus (1) includes a filter (4) which is arranged between the X-ray source (2) and the X-ray detector (3). The X-ray filter includes a large number of filter elements (5); the X-ray absorptivity of the filter elements can be adjusted by controlling the quantity of X-ray absorbing liquid (6) than individual filter elements. The filter elements are formed by metal capillary tubes or the wall of the capillary tubes, or the wall of the capillary tubes is provided with a metal layer (7). On the metal layer there is provided a dielectric layer (8) and the dielectric layer is covered by a coating layer (9). The dielectric layer is, for example a glass, parylene or polystyrene layer. The coating layer is, for example a Teflon, silane or siloxane layer. The dielectric layer can be dispensed with when a Teflon coating layer is used.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: May 12, 1998
    Assignee: U.S. Philips Corporation
    Inventors: Wilhelmus J. J. Welters, Jacob Wijdenes
  • Patent number: 5680435
    Abstract: An X-ray diagnostic apparatus has a device for controlling an X-ray source with regard to the emission of an X-ray beam and a filter positioner for the introduction or removal of at least one radiation filter into or out of the beam of radiation. A monitoring device checks whether there exists a positive difference signal between an output of a dosage power regulator and a kV controller. Given the presence of a positive difference, the monitoring device controls the filter positioner with regard to the removal of the radiation filter from the beam of radiation.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: October 21, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventors: Johann Seissl, Heinz Eschenbacher
  • Patent number: 5679502
    Abstract: An X-ray source such as a synchrotron which provides a significant spectral content of hard X-rays is used to expose relatively thick photoresist such that the portions of the photoresist at an exit surface receive at least a threshold dose sufficient to render the photoresist susceptible to a developer, while the entrance surface of the photoresist receives an exposure which does not exceed a power limit at which destructive disruption of the photoresist would occur. The X-ray beam is spectrally shaped to substantially eliminate lower energy photons while allowing a substantial flux of higher energy photons to pass through to the photoresist target. Filters and the substrate of the X-ray mask may be used to spectrally shape the X-ray beam. Machining of photoresists such as polymethylmethacrylate to micron tolerances may be obtained to depths of several centimeters, and multiple targets may be exposed simultaneously.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: October 21, 1997
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: David Peter Siddons, Erik D. Johnson, Henry Guckel, Jonathan L. Klein
  • Patent number: 5677943
    Abstract: An x-ray filter which produces a uniform distribution of the image contrast and the image brightness, with an optimally reduced skin dose has a pre-filter for the total x-ray beam and an edge filter, which leaves free a central region of the x-ray beam. The pre-filter is made of a material having an atomic number less than 60, such as copper, and the edge filter is made of a material having an atomic number between 64 and 77.
    Type: Grant
    Filed: August 28, 1996
    Date of Patent: October 14, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventor: Peter Hoebel
  • Patent number: 5666396
    Abstract: An X-ray examination apparatus in accordance with the invention includes a filter (4) for limiting the dynamic range of an X-ray image which is formed on an X-ray detector (4) by irradiation of an object (3), for example a patient to be examined, by means of X-rays (15). The filter (4) includes filter elements (5), being capillary tubes (5), one end of which communicates with an X-ray absorbing liquid. The adhesion of the X-ray absorbing liquid to the inner side of the capillary tubes is adjustable by means of an electric voltage which can be applied to an electrically conductive layer (36) provided on the inner side of the capillary tubes (5). The filling of the capillary tubes (5) with the X-ray absorbing liquid is adjusted on the basis of the period of time during which the electric voltage is applied. This period of time can be subdivided into a number of fractions and individual rows of capillary tubes are then filled with the X-ray absorbing liquid partly in parallel.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: September 9, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Petrus W. J. Linders, Christianus G.L.M. Nederpelt
  • Patent number: 5625665
    Abstract: An X-ray apparatus is provided with a filter (12) for limiting the dynamic range of an X-ray image formed on an X-ray detector (4) by exposure of an object (3), for example a patient to be examined, to X-rays (2). The filter (12) has filter elements (13) including one or more capillary tubes (13), one end of which communicates with a reservoir with an X-ray absorbing liquid. The adhesion of the X-ray absorbing liquid to the inner side of the capillary tubes can be adjusted by means of an electric voltage applied to an electrically conductive layer provided on the inner side of the capillary tubes (13). The degree of filling of the capillary tubes (13) with the X-ray absorbing liquid is adjusted by way of the electric voltage value. The X-ray absorption profile is adjusted within a very short period of time, for example within one second, by adjustment of the electric voltages applied to the capillary tubes (13).
    Type: Grant
    Filed: October 20, 1995
    Date of Patent: April 29, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Lambertus G. J. Fokkink, Petrus W. J. Linders, Johanna A. M. Sondag-Huet-Horst, Andre R. De Wit, Rudolf Kemner, Frans J. A. Berkers
  • Patent number: 5568533
    Abstract: A K-filter is the one attached to an apparatus for serial high-speed rotatography for photographing an object to be examined by use of X-rays. The filter comprises two K-containers (5a and 5b) in which a space is defined for fluidly containing a radiopaque fluid substance, and a radiotransparent region (2) formed between the two K-containers (5a and 5b). The K-containers (5a and 5b) are pivotally supported by a supporting member (1a) and are of the inversion type which allows the radiotransparent region sides of the K-containers to move. Therefore, when this apparatus is rotated at a high speed to more than 180.degree., it is possible to conduct filtering under any conditions such as an inclined posture, not the horizontal posture, under which photographing is started.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: October 22, 1996
    Assignees: Tatsuo Kumazaki, Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Tatsuo Kumazaki, Hifumi Yamada
  • Patent number: 5559853
    Abstract: An X-ray examination includes a filter for limiting the dynamic range of an X-ray image formed on an X-ray detector by irradiation of an object, for example a patient to be examined, by means of X-rays. The filter has a number of electrodes and grains or powder particles containing an X-ray absorbing material and suspended in a suspension liquid. When a voltage is applied to electrodes, X-ray absorbing material in the suspension will move to the excited electrodes under the influence of electrophoresis. A distribution with a desired X-ray absorption profile is adjusted by application of a suitable voltage pattern. The electrodes may have dimensions of, for example 0.5.times.0.5 mm, enabling an X-ray absorption profile to be obtained with a high spatial resolution. The X-ray absorption profile can be changed within a brief period of time, for example within one second, by changing the voltage pattern on the electrodes.
    Type: Grant
    Filed: July 3, 1995
    Date of Patent: September 24, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Petrus W. J. Linders, Marcel R. Bohmer, Michael J. M. J. Severens
  • Patent number: 5528647
    Abstract: X-ray Fluorescence Inspection Apparatus comprises an X-ray tube (1) for generating X-rays having a range of energies which are directed towards a sample position. A first filter assembly (3) is mounted between the X-ray tube (1) and the sample position and is movable between at least two positions to enable the energy band of X-rays reaching the sample position to be controlled in two different ways. An X-ray monitor (8) monitors X-rays from the sample position; and a second filter assembly (6) mounted between the sample position and the monitor (8) is movable between at least two positions to enable the energy band of X-rays reaching the monitor to be controlled in two different ways.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: June 18, 1996
    Assignee: Oxford Analytical Instruments Limited
    Inventors: Robin J. Anderson, Trevor A. Nunn
  • Patent number: 5526394
    Abstract: An apparatus is disclosed for imaging a patient's breast (18) by scanning an imaging signal (58) and a receiver (30) across the patient's breast (18) and then constructing a time-delay integration composite image based on the scan. The receiver (30) includes an array of radiation sensitive detector elements (132). Read out of the array (132) is synchronized with the scanning motion of the receiver (30) based on output from position encoder (104) such that synchronization is maintained despite scan drive variances. A novel assembly (106) is also disclosed for allowing selection of an appropriate radiation filter based on particular imaging conditions.
    Type: Grant
    Filed: November 26, 1993
    Date of Patent: June 11, 1996
    Assignee: Fischer Imaging Corporation
    Inventors: Bernard Siczek, Emre Toker
  • Patent number: 5503958
    Abstract: In one embodiment of the invention x-rays pass through an aluminum filter (18) to form filtered x-rays. At least a portion of the filtered x-rays then pass through a portion of a x-ray mask (22) to expose a portion of a photoresist layer overlying a semiconductor substrate. The aluminum filter removes high energy photons from the x-ray spectrum that adversely effect the lithographic patterning process.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: April 2, 1996
    Assignee: Motorola Inc.
    Inventor: Whit G. Waldo