Moving Source And Detector Patents (Class 378/39)
  • Patent number: 5214686
    Abstract: A panoramic dental radiography system projects multiple vertical, fan-shaped radiation beams through a subject's teeth and onto multiple detectors, with each fan-shaped beam avoiding the subject's spine. The radiographic source and radiographic detectors are rotated about a vertical axis, so that the detected radiation may be tomographically processed to produce a panoramic image of the teeth. The multiple vertical fan-shaped radiation beams are projected on either side of the spine, to reduce the radiographic dosage to the spine and to prevent the spine from blurring the panoramic radiograph. The resulting multiple projections can be tomosynthetically processed to produce a three-dimensional image of tissues of diagnostic interest, free of image artifacts produced by irradiation of the spine.
    Type: Grant
    Filed: December 13, 1991
    Date of Patent: May 25, 1993
    Assignee: Wake Forest University
    Inventor: Richard L. Webber
  • Patent number: 5195114
    Abstract: The apparatus of the present invention comprising a rotary means having an X-ray source disposed opposite to an X-ray image detection section for detecting the image of the X-ray which penetrated an object to be photographed, with the object positioned therebetween, and rotating the X-ray source and the X-ray image detection section as an integrated unit around the object, an image storage means which sequentially stores image information obtained by the X-ray image detection section as frame images, and an image processing means which sequentially derives image information from the image storage means at predetermined time intervals, adds the information of each image while shifting the information of each image by a predetermined distance in the image movement direction along a series of image information to digitally form the panoramic image of a given tomographic image layer depending on the interval for deriving the information of each image and the shift amount.
    Type: Grant
    Filed: October 1, 1991
    Date of Patent: March 16, 1993
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventors: Eiko Sairenji, Yoshinori Arai
  • Patent number: 5179579
    Abstract: A method and apparatus for storing and displaying radiographs, particularly intra-oral radiographs, is presented. Radiographs are captured, digitized, and displayed along with an icon of a portion of the anatomy from which the radiograph was taken. The anatomical sites represented by the icon are arranged according to their normal anatomical relationship. The icon is used by the system user to select a portion of the anatomy corresponding to the displayed radiograph, and the radiograph is stored along with indicia of the selected anatomical site. Then, when the stored radiograph is desired to be viewed, the icon is again displayed, and the appropriate anatomical site is selected, which causes the corresponding radiograph to be retrieved from storage and displayed.
    Type: Grant
    Filed: June 17, 1991
    Date of Patent: January 12, 1993
    Assignee: Board of Regents, The University of Texas System
    Inventors: S. Brent Dove, W. Doss McDavid, C. Donald Wilcox
  • Patent number: 5093852
    Abstract: A medical panoramic radiographing device comprises in combination a mode selector which is used to select the panoramic radiographing mode, jaw joint radiographing mode and/or otolaryngological region radiographing mode, an X-ray irradiation timing determination means which is used to determine the X-ray irradiation timing appropriate to the rotation positon of a rotary arm in the sselected radiographing mode, and an X-ray film movement pattern determinator which is used to determine movement patterns regarding the movement timing, speed, etc. of an X-ray film depending on the selected radiographing mode. With this device, the X-ray irradiation timing values or the X-ray film movement timing values suited for various radiographing modes are set automatically to ensure systematic selection of various radiographing modes.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: March 3, 1992
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventors: Kazuo Nishikawa, Kozo Nakano, Keisuke Mori, Takahiro Yoshimura
  • Patent number: 5033070
    Abstract: A panoramic method for the radiography of the dental arch and jaws, in which method by means of movable radiographing and/or imaged elements, several subsequent exposure sweep sequences are performed so that the moving elements are transferred to a new position betwen the subsequent exposure sequences. In order to achieve a perfectly jointed X-ray picture, the movement of the moving elements is started before the switch-on instant of the X-ray beam in the latter exposure sequence and the starting positions of said elements is selected so as to obtain desired positions and velocities for the elements at the switch-on instant of the X-ray beam. The coincidence of the X-ray beam orientation at the start of the latter exposure sequence with the X-ray beam orientation at the end of the preceding sequence is characterizing to an embodiment of the invention.
    Type: Grant
    Filed: January 9, 1990
    Date of Patent: July 16, 1991
    Assignee: Orion-Yhtyma Oy
    Inventors: Heikki K. J. Kanerva, Erkki H. Tammisalo, Pasi T. Mustalahti, Olli J. Ojala
  • Patent number: 5018177
    Abstract: Apparatus and method for producing a digital panoramic X-ray image of an object is disclosed. The system of the invention includes an X-ray source and a digital radiation detector, which move around the object in unison in a certain time period. The radiation detector produces pixel data signals that are proportional to the incident X-rays on it. The pixel data signals are integrated over a series of varying time intervals to obtain pixel data signals which are proportional to the X-rays incident upon the radiation detector during each time interval. The integrated pixel data signals are converted into digital signals, which are then used to produce a digital X-ray image of the object.
    Type: Grant
    Filed: June 1, 1989
    Date of Patent: May 21, 1991
    Assignee: Board of Regents, The University of Texas System
    Inventors: W. Doss McDavid, S. Brent Dove, Ulf Welander, Gunilla Tronje
  • Patent number: 5016264
    Abstract: The invention relates to a transfer method and an arrangement for a film cassette unit in a panoramic X-ray apparatus. A film cassette unit (6), comprising a film cassette and cassette aggregate, is transferred either manually or electrically upwards from between patient and operator. After positioning a patient, prior to effecting the imaging, the film cassette unit (6) is lowered or descends automatically down to an imaging position. The transfer can be effected either by turning around a horizontal shaft (9) or by moving in vertical plane.
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: May 14, 1991
    Assignee: Instrumentarium Corp.
    Inventor: Klaus Hyttinen
  • Patent number: 5014293
    Abstract: A scanner assembly having a C-shaped gantry rotatably supported by a support head. An x-ray source and a detector assembly are mounted on said gantry for independent movement with respect to one another along said gantry.
    Type: Grant
    Filed: October 4, 1989
    Date of Patent: May 7, 1991
    Assignee: Imatron, Inc.
    Inventors: Douglas P. Boyd, Giovanni Lanzara
  • Patent number: 5012501
    Abstract: Apparatus for producing panoramic x-ray image projections of the dental arch on X-ray film. The apparatus includes a fixed body (1). The opposite ends of a movable supporting arm (11) are fitted with an X-ray source (12) and a film holder (13) that may be positioned on opposite sides of the dental arch. A first drive (20-23) produces a rotating motion of supporting arm (11) with respect to the arch. A second drive (2, 4) sets the center of rotating motion in linear movement in dependence on the angular position of supporting arm (11). The apparatus further includes a selector (3, 6, 10) for selecting the direction of linear motion (translatory motion) as desired.
    Type: Grant
    Filed: March 28, 1990
    Date of Patent: April 30, 1991
    Assignee: Instrumentarium Corp.
    Inventors: Juhani Palonen, Hannu Purhonen
  • Patent number: 4974243
    Abstract: An instrument and system precisely positions a selected cranial implant site for X-ray tomography. The system and method involve first positioning the patient accurately in a straight-ahead reference position using a cephalostat, with the ears positioned in the vertical plane containing all X-ray axes and at a particular reference level which may be the level of horizontal X-ray projection. The apparatus includes a pointer system which pivots on the cephalostat vertical center of rotation to measure the angle to a site of interest on the mandible or maxilla, with an adjustable pointer for measuring the height and radial distance of the site from reference positions. The pointer may be extended to directly contact the site of interest on the patient. The information thus obtained gives polar coordinates of the site.
    Type: Grant
    Filed: December 4, 1989
    Date of Patent: November 27, 1990
    Assignee: Axialtome Corporation
    Inventors: Phillip C. McArdle, Steven P. McEvoy
  • Patent number: 4955042
    Abstract: A dental radiographic apparatus for photographing the entire jaws in which the apparatus includes a rotary arm having an X-ray source at one end and an X-ray film cassette at the other end thereof and operating in the manner that a path of movement of X-ray beam with respect to the dental arch describes a symmetrically extending approximately triangular envelope projecting toward the front tooth region of the dental arch by sequentially shifting the center of rotation of the X-ray beam irradiated from the X-ray source upon the X-ray film cassette, the apparatus being characterized in that it comprises a means for changing the straight-line distance on the medial line of the human body between the apex and receding points of limit of the envelope.
    Type: Grant
    Filed: June 5, 1989
    Date of Patent: September 4, 1990
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventor: Kazuo Nishikawa
  • Patent number: 4907251
    Abstract: A patient positioning device in a medical panorama X-ray photographing apparatus in which after data of the relative position of the subject to the X-ray photographing apparatus supplied from a sensor is compared with data of the relative position of a tomographic zone to the X-ray photographing apparatus thus to produce comparison data which is in turn transmitted to a drive circuit, a tomograph forming assembly and/or the subject is moved from coinciding with each other. The device further includes a comparing arithmetic circuit in which the detected position data of the subject and position data of the tomographic zone are arithmetically compared in order to improve operatability and positioning accuracy. The device furthermore includes a sensor which is adjustable for angular and vertical setting with the use of sensing position changing means in order to improve adaptability to individualities of the subject.
    Type: Grant
    Filed: March 10, 1988
    Date of Patent: March 6, 1990
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventors: Keisuke Mork, Takao Makino, Kazuo Nishikawa, Yoshiaki Iwato, Takahiro Yoshimura
  • Patent number: 4870673
    Abstract: A dental x-ray diagnostics installation having a holder for film cassette and a holder for diaphragms of different sizes, which holder for diaphragms is positioned in an x-ray source so that the beam passes through the diaphragm aperture before reaching the subject. The diaphragms are interchangeable with one another and have different diaphragm apertures for the purpose of matching the x-ray beam cross-section to different film cassette formats.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: September 26, 1989
    Assignee: Siemens Aktiengesellschaft
    Inventors: Rolf Adler, Erich Heubeck, Manfred Muether
  • Patent number: 4856038
    Abstract: A dental x-ray diagnostic installation for the production of panoramic exposures of slices of the skull of the patient particularly in the region of the jaw, characterized by an exposure unit with an x-ray unit pivotable around an axis and displaceable in a plane perpendicular to the axis, a film holder unit lying opposite and moveable relative to the x-ray unit, a head holder arranged between the two units, a control arrangement for controlling the pivoting and displacement movement of the exposure unit relative to the head holder and also controlling the movement of the film holder relative to the x-ray tube of the exposure means and an input arrangement for inputting information of the selected curvature of the slice being exposed. The improvements are that the input means is constructed so that the curvature of the slice to be exposed can be directly graphically inputted into the control arrangement such as by means of a monitor with a light pen or by means of a "computer graphic tablet".
    Type: Grant
    Filed: September 28, 1987
    Date of Patent: August 8, 1989
    Assignee: Siemens Aktiengesellschaft
    Inventors: Werner Guenther, Erich Heubeck, Manfred Muether
  • Patent number: 4852134
    Abstract: A method and an apparatus for the radiographic recording of a patient's dentition, jaws, and skull regions invalues seating a patient in a patient chair (9) so as localize the patient in the coordinate system of the radiographic apparatus in an unequivocal position before taking the exposure for a radiograph (87). Furthermore, in accordance with the invention, the radiograph (87) is used for measuring the coordinates of a desired object (95) by a coordinate locator (88), after which the desired partial area (94 or 96) is selected on the basis of the coordinates, and the exposure direction is changed in relation to the first exposure in the horizontal plane and/or the vertical plane before executing the exposure program for the desired partial area (94 or 96).
    Type: Grant
    Filed: February 4, 1987
    Date of Patent: July 25, 1989
    Assignee: Orion-Yhtyma Oy
    Inventors: Ilmari Kinanen, Heikki Kanerva, Erkki Tammisalo
  • Patent number: 4823369
    Abstract: A dental x-ray diagnostics installation has a rotary unit carrying an x-ray source and a radiation detector disposed behind a secondary diaphragm, the rotary unit rotating around the jaw of a patient to produce panorama tomograph exposures of the patient's jaw. The radiation detector generates electrical signals proportional to the incident radiation intensity. To simplify signal processing, the detector is formed of one or more semiconductor detectors having a scintillation layer which corresponds to the size of the opening in the secondary diaphragm. The voltages acquired by the detector are converted to digital form, and stored in an image memory. A computer calculates a total image from the signals supplied by the detector, and stored in the memory, during a complete exposure. The signals from the image memory are combined to generate a tomogram of a desired slice of the patient's jaw.
    Type: Grant
    Filed: December 31, 1987
    Date of Patent: April 18, 1989
    Assignee: Siemens Aktiengesellschaft
    Inventors: Werner Guenther, Manfred Muether, Erich Heubeck, Michael Doebert, Leonhard Werner
  • Patent number: 4819254
    Abstract: The invention relates to a method of and an apparatus for recording image information in panoramic X-ray photography. The total information contained in a beam of X-rays penetrated through an object is recorded on a memory disc, whose configuration is substantially the same as that of an object to be imaged, such as a dental arch, said memory disc being kept stationary during the filming relative to the object to be imaged. The memory disc is used for producing or presenting layerwise reproduced images of desired layers. The preparation of reproduced images from the memory disc can be performed on a principle corresponding to conventional panoramic tomography with the exception that the object to be imaged is a memory disc.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: April 4, 1989
    Assignee: Radiante Oy
    Inventors: Timo Nieminen, Tero Nieminen
  • Patent number: 4815115
    Abstract: The invention relates to a method of photographing a desired object with a panoramic X-ray apparatus fitted with automatic exposure, comprising an X-ray generator (4, 5), an X-ray tube (5) and a film (7) with its holder. In the method, the detection of a cone of rays (9) penetrated through an object is effected before the actual filming is started and, after the detection, the filming is effected by using a cone of rays (6), directed so as to bypass a detector (1).
    Type: Grant
    Filed: February 5, 1987
    Date of Patent: March 21, 1989
    Assignee: Radiante OY
    Inventors: Tero Nieminen, Timo Nieminen
  • Patent number: 4813060
    Abstract: A dental diagnostic apparatus or installation which obtains a better matching of the exposure data to the patient and has a rotary unit carrying the radiation source and the film cassette which are adjustable to an initial position by an adjustment arrangement and from this initial position the film cassette can be charged with the radiation within the framework of normal transillumination with the radiation initially beginning outside of the mandibular arch. The incoming radiation dose is measured by a detector arrangement which creates a signal that is compared in a computational unit of a control arrangement to a rated quantity corresponding to a prescribed dose value. The exposure data required from further transillumination of the patient's head are identified therefrom and the tomogram position is determined by identifying the patient-associated film speed via the jaw length/jaw width measurements and comparison to defined rated value.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: March 14, 1989
    Assignee: Siemens Aktiengesellschaft
    Inventors: Erich Heubeck, Werner Gunther, Manfred Muther, Leonhard Werner
  • Patent number: 4811372
    Abstract: In order to provide a dental X-ray diagnostic installation for producing panoramic tomograms of the jaw of the patient and to achieve a simple structure with improved image quality, the apparatus includes an adjustment mechanism for the carrier of the radiation source and the film cassette holder to be adjusted in an orbital curve corresponding to the dental arch of the patient. The adjustment arrangement includes first adjustment parts with which the carrier can be rotated around a first vertical axis, and second adjustment elements for moving or swivelling the first axis in an arch transverse relative to the symmetry axis of the subject during the rotary motion. The swivel radius and the amount of excursion of this swivel motion are selected so that the perpendicular transillumination direction through the subject gives a constant distance between the subject and the film during the motion of the rotary unit. To accomplish this, the invention includes two separate embodiments with various modifications.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: March 7, 1989
    Assignee: Siemens Aktiengesellschaft
    Inventors: Michael Doebert, Werner Guenther, Erich Heubeck, Manfred Muether, Dieter Molitor
  • Patent number: 4783793
    Abstract: Panoramic tomography X-ray apparatus such as for obtaining images of dental systems, comprises a rotatably mounted arm to which the X-ray tube of an X-ray generator and an X-ray film cartridge, along with film transport equipment, are mounted, and a control system for controlling the functioning of the equipment of the apparatus on the basis of control data and a program pre-stored therein. A control system controls the speed of a rotary motion motor that rotates the arm, the speed of the film transport motor and the distribution of those speeds, independently of each other. In this manner, it is possible to photograph dental systems of varying sizes and shapes both sharply and with suitable exposure time. In addition to controlling the speeds of the rotary motion and film transport motors, the control system may also control the anode current and/or the anode voltage of the X-ray generator during the exposure sequence.
    Type: Grant
    Filed: September 9, 1986
    Date of Patent: November 8, 1988
    Assignee: Planmeca Oy
    Inventors: Arto Virta, Pekka Strommer
  • Patent number: 4756014
    Abstract: An x-ray diagnostic installation for producing panoramic tomograms of the jaw of a patient utilizes a flexible film cassette instead of a rigid film cassette. The film cassette is driven by an electromotive drive arranged in a housing of a film cassette holder behind a secondary diaphragm as seen in the direction of the radiation from a source of radiation. The drive is formed from by at least one drive element, and at least one cooperating element arranged thereto at a distance therefrom with means biasing at least one of the elements towards the other to produce a frictional engagement of the film cassette and move it past the secondary diaphragm.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: July 5, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Michael Dobert
  • Patent number: 4741007
    Abstract: A panoramic tomography X-ray apparatus comprises a fixed frame to which another rotary frame is suspended, the rotary frame having an X-ray tube at one end thereof and a film cartridge device for X-ray film at an opposite end thereof. Drive mechanism for turning the rotary frame in a substantially horizontal plane is provided, for taking a panoramic X-ray photograph. The drive mechanism comprise a drive and guide groove which has straight side sections and a curved section connecting the side sections together and a drive unit also comprising a drive wheel which, when rotated by the drive unit, turns the rotary frame. The rotary frame is suspended from the fixed frame by a crank mechanism which is joined to both the rotary frame and to the fixed frame through respective sets of bearings. The drive and guide mechanism along with the crank mechanism interact in such a manner that, in the front area of a dental arch, i.e.
    Type: Grant
    Filed: May 30, 1986
    Date of Patent: April 26, 1988
    Assignee: Planmeca Oy
    Inventors: Arto Virta, Pekka Strommer
  • Patent number: 4694478
    Abstract: An apparatus for orthoradial panoramic tomography comprises a radiation source for motion relative to a point of reference; a cassette means also for motion relative to said point of reference; a support for holding said radiation source and said cassette relative to said point of reference; a head positioning means including a first or intraoral device and a second or extraoral device for positioning the patient's head relative to said point of reference; a carriage connected with said support 11 and including a grip; a substantially vertical column for slidingly holding said carriage in a vertically defined position and having a vertical axis distanced from said point of reference; the apparatus further comprises a foot positioning means having a substantially horizontal reference face for defining a vertical distance from said horizontal reference face to said point of reference and a substantially vertical reference face for maintaining toe and/or heel portions of the patient's feet in a predetermined pos
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: September 15, 1987
    Inventor: Hanspeter Delnon
  • Patent number: 4675888
    Abstract: The invention relates to a patient support system in a narrow-beam tomographic X-ray apparatus, having a fixed frame fitted with a substantially vertical member (1), means (7, 8, 9) mounted on the frame for supporting a patient's head, said means being adapted to hold a patient's head (P) steady during the imaging session, as well as a bearer bar (3), fitted with a source of X-radiation (4) and imaging instruments (5) on the opposite sides relative to an object to be imaged and said bar being adapted in a known manner to perform rotational or combined rotational linear movement for scanning a predetermined layer to be imaged. In order to facilitate patient positioning and to secure proper positioning of a patient, said head support means (7, 8, 9) are set in a manner that the medial sagittal plane (S) of a patient supported thereby does not intersect said vertical frame member (1).
    Type: Grant
    Filed: January 2, 1985
    Date of Patent: June 23, 1987
    Assignee: Instrumentarium Corp.
    Inventor: Jan Gastrin
  • Patent number: 4661967
    Abstract: A dental radiographic apparatus for photographing the entire jaws in which the apparatus includes a rotary arm having an X-ray source at one end and an X-ray film cassette at the other end thereof and operating in the manner that a path of movement of X-ray beam with respect to the dental arch describer a symmetrically extending approximately triangular envelope projecting toward the front tooth region of the dental arch by sequentially shifting the center of rotation of the X-ray beam irradiated from the X-ray source upon the X-ray film cassette, the apparatus being characterized in that it comprises a means for changing the straight-line distance on the medial line of the human body between the apex and receding points of limit of the envelope.
    Type: Grant
    Filed: November 2, 1984
    Date of Patent: April 28, 1987
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventor: Kazuo Nishikawa
  • Patent number: 4641331
    Abstract: An automatic exposure device for obtaining X-ray pictures with superior quality and constant contrast by feedback of both tube voltage and tube current according to the residual X-ray dose which penetrates the body of a patient. This device is further characterized in that the feedback control is compensatingly done according to the changes in the tube voltage and tube current caused by fluctuations of the power supply.
    Type: Grant
    Filed: August 1, 1984
    Date of Patent: February 3, 1987
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventors: Takao Makino, Shinichi Osada
  • Patent number: 4599739
    Abstract: A radiographic apparatus for photographing the entire jaws designed to make a tomogram of a curved plane approximate to a dental arch by the locus of center of rotation of the X-ray beam projected from an X-ray source onto an X-ray film holder describing an approximately V-shaped envelope which forms an apex on an approximate medial line and recedes from the apex toward the left and right of the approximate medial line by moving a rotary arm around a patient, the arm having the X-ray source at one end and the X-ray film holder at the other end thereof, wherein the apparatus comprises a means for changing straight-line distance on the approximate medial line between the apex and receding point of limit of the envelope and a means for indicating the distance of shift thus changed or a means for automatically moving the indication means a distance equal to the distance of shift.
    Type: Grant
    Filed: January 18, 1985
    Date of Patent: July 8, 1986
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventors: Kazuo Nishikawa, Keisuke Mori
  • Patent number: 4589121
    Abstract: A dental panoramic X-ray photographing apparatus including a rotary arm having an X-ray generator disposed at one end thereof and having an X-ray film cassette holder disposed at the other end thereof in an opposite relation with each other around an object disposed therebetween. The apparatus comprises a first control means for controlling the rotation speed of the arm by detecting the rotation position of the arm and a second control means for controlling the tube voltage and the tube current of the X-ray generator by comparing the feeding speed of the X-ray film at the X-ray film cassette holder with the residual X-ray dose which has passed the object and the film, whereby it is intended to provide the simultaneous control function of the tube voltage and the tube current, the function for automatic exposure throughout the entire teeth and the function for compensating for the density of the central portion of the front tooth region of a dental arch at the same time.
    Type: Grant
    Filed: January 25, 1985
    Date of Patent: May 13, 1986
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventor: Takao Makino
  • Patent number: 4589122
    Abstract: The invention relates to a panoramic tomography X-ray apparatus, particularly a so-called narrow beam tomographic apparatus for imaging the teeth and jaw area of a patient, wherein an X-ray source (14) and imaging means, e.g. a film cassette (6), are by means of an arm member (13) or the like connected to each other on opposite sides of a target to be imaged and adapted for the actual imaging to be rotated around said target to be imaged. For establishing a constant magnification or enlargement and reducing a radiation dosage the apparatus comprises means for moving said imaging means during the imaging in the direction parallel to a beam of X-rays (15) in a manner that the distance of said imaging means from a selected layer to be imaged remains substantially unchanged. In practice, this is achieved by employing a guide profile (2), from which said imaging means are kept during the imaging at a constant distance by means of a motion in the direction of said beam of X-rays (15).
    Type: Grant
    Filed: September 20, 1984
    Date of Patent: May 13, 1986
    Assignee: Instrumentarium Corp.
    Inventor: Timo Nieminen
  • Patent number: 4534048
    Abstract: Effective centers of rotation of the X-ray beams when projecting the anterior regions are caused to be disposed considerably more interiorly of the dental arch, i.e., farther from the incisors and closer to the X-ray source, to thus provide longer projection radii of the beams at the anterior region. Lengthening of the projection radii is achieved through unique velocity profiles of patient chair movement along an x-axis and film travel within the camera. The longer effective projection radii of beams at the anterior region provide for a substantially wider or thicker layer thereat with a concomitant modest narrowing of the layer at the canine regions.
    Type: Grant
    Filed: January 3, 1983
    Date of Patent: August 6, 1985
    Assignee: Pennwalt Corporation
    Inventors: Ulf E. S. Welander, William D. McDavid, Charles R. Morris
  • Patent number: 4449225
    Abstract: The invention relates to carrying out a pre-adjustment, before photographing is started, in panoramic X-ray photography using an X-ray device which performs a rotational movement and supports a moving film and an X-ray source. The object is to achieve a correct positioning of the focus in relation to the patient. This is achieved without moving either the patient or the X-ray apparatus, or more precisely, merely by selecting the correct ratio between the film speed and the movement of the X-ray apparatus, instead of mechanical movement. In the apparatus, a viewing member is used, and the correct speed variation curve for the film during the photographing movement is selected on the basis of the position or reading of the viewing member. The film is reeled preferably by means of an electric motor, in which case a sensor can be connected to the sighting member, and the motor is controlled electronically according to the electric output signal of the sensor by means of, for example, a microprocessor.
    Type: Grant
    Filed: February 16, 1982
    Date of Patent: May 15, 1984
    Inventor: Erkki Tammisalo
  • Patent number: 4365340
    Abstract: This disclosure relates to an X-ray photographing apparatus both for photographing the entire jaws and for cephalographic use. The apparatus is constructed in such a manner that, in setting the generator in any direction either for cephalographic use or for use in photographing the entire jaws, the X-ray generator is automatically vertically rotated through a specified angle and is enabled to make simple and correct change in the direction of irradiation by providing the X-ray generator mounted horizontally and vertically rotatably at one end of a rotary arm with a sliding element, providing the arm with an inclined guide groove for guiding the element therein, and merely rotating the generator horizontally through a specified angle.
    Type: Grant
    Filed: June 16, 1981
    Date of Patent: December 21, 1982
    Assignee: Kabushiki Kaisha Morita Seisakusho
    Inventors: Kazuo Nishikawa, Kazuo Hozumi