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公开(公告)号：EP0104928A3
公开(公告)日：1985-09-11
申请号：EP83305745
申请日：1983-09-26
CPC分类号： G01S15/8922 , G01S15/895 , G10K11/32 , G10K11/345
摘要： An ultrasonic diagnostic imaging system is described in which a multi-element transducer array transmits a focused beam of energy from the transducer elements. As the depths of focus'is varied between near and far field focusing under operator control, the nominal frequency of the transmitted ultrasound energy is varied correspondingly by the system, from relatively high frequency transmission in the near field to relatively low frequency transmission in the far field.
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公开(公告)号：EP0145277A1
公开(公告)日：1985-06-19
申请号：EP84307728.0
申请日：1984-11-08
IPC分类号： G01R33/20
CPC分类号： G01R33/565
摘要： In an NMR imaging system, two-pulse excitation sequences are used to acquire lines of NMR signal information. Artifact signal components may also be present during the times of NMR signal acquisition. In order to remove these artifacts from the center of the image, the artifact signals are alternately phase-encoded from line to line by alternating the phase of one of said excitation pulses from line to line. Fourier transformation is performed on the lines of information in at least the direction of alternate phasing of the artifact components, which relocates the artifacts to the edge of the resulting image.
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公开(公告)号：EP0145276A1
公开(公告)日：1985-06-19
申请号：EP84307727.2
申请日：1984-11-08
IPC分类号： G01R33/20
CPC分类号： G01R33/565
摘要： In an NMR imaging system, an image plane is scanned and NMR signals are collected over a plurality of image lines. The experiment is repeated, with the timing of the excitation pulses changed. Images are formed by performing Fourier transformations of the signal values. A ratio image is then formed by performing a complex division of the two images on a pixel by pixel basis. The ratio values cancel phase error effects in the image data and the use of complex numbers maintains the proper pixel polarity.
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公开(公告)号：EP0136864A2
公开(公告)日：1985-04-10
申请号：EP84306373.6
申请日：1984-09-18
CPC分类号： H01J35/16 , H01J35/101 , H01J2235/1266 , Y10S277/913 , Y10T29/49888
摘要： A method of assembling a rotating anode X-ray tube wherein a temporary static seal on the rotor of the anode is compressed to seal the anode region, lowering the pressure in the anode region, installing a magnetic seal assembly about the rotor, installing bearings adjacent the magnetic seal and outside the low pressure region, and releasing the temporary static seal.
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95.发明公开Point selection and position indicating apparatus 失效Apparat zur Auswahl und zur Positionsangabe eines Punktes。
公开(公告)号：EP0125778A2
公开(公告)日：1984-11-21
申请号：EP84302371.4
申请日：1984-04-06
IPC分类号： G05B19/18
CPC分类号： G05B19/23 , G05B19/4015
摘要： Apparatus for use in selecting a point or plane in an object translatable along a path, and for indicating the distance of the selected point or plane from a predetermined position in the path. A reference point in the path is established by a line of light projected onto the translatable object. When the line of light identifies a point or plane of interest in the object, a reset signal is transmitted to a computer. The reset signal causes a number, a reset quantity representing the known distance between the reference point or line of light and the predetermined position, to be recorded in computer memory. As the object then is translated along the path, an encoder supplies signals to a counter that is incremented or decremented in response to movement of the object toward or away from the predetermined position. The reset quantity initially has the count both added to it and subtracted from it and the result, the reset quantity, is displayed by the computer. As the count in the counter changes during movement of the object toward or away from the predetermined position, the displayed result changes accordingly. The apparatus may be used in properly positioning a patient in a medical imaging system.
摘要翻译： 用于选择可沿着路径平移的物体中的点或平面并用于指示所选择的点或平面距路径中的预定位置的距离的装置。 通过投影到可平移对象上的光线建立路径中的参考点。 当光线识别物体中感兴趣的点或平面时，将复位信号发送到计算机。 复位信号使代表基准点或光线与预定位置之间的已知距离的数字被记录在计算机存储器中。 随着物体沿路径平移，编码器响应于物体朝向或远离预定位置的移动而将信号提供给计数器，该计数器递增或递减。 复位数量最初具有相加的计数并从中减去计数，计算机显示复位数量。 当计数器在物体朝向或远离预定位置移动期间改变时，显示的结果相应地改变。 该装置可以用于将患者适当地定位在医学成像系统中。
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公开(公告)号：EP0038665B1
公开(公告)日：1984-09-26
申请号：EP81301634.2
申请日：1981-04-14
IPC分类号： H04N5/32
CPC分类号： H04N5/3205
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公开(公告)号：EP0086560A1
公开(公告)日：1983-08-24
申请号：EP83300212.4
申请日：1983-01-17
CPC分类号： H01F7/20 , G01R33/385
摘要： Apparatus for imposing a gradient magnetic field intensity on a static magnetic field intensity in a nuclear- magnetic-resonance (NMR) system. The gradient field has a predetermined error relationship with respect to a desired characteristic of the gradient field within a selected region. The selected region is substantially smaller in volume than the volume «enclosed» by a surface or surfaces on which electrical conductors are distributed to generate the gradient field. The surface current densities in a grid-like pattern of differential areas on the surfaces are chosen such that, within the selected region, the predetermined error relationship results. The gradient field intensity outside of the selected region generally does not have the characteristic desired within the region. The predetermined error relationship can be established in a linearly-varying field intensity in a spherical volume enclosed by a cylindrical surface. Generally hyperbolically-shaped electrical coils on the cylindrical surface can provide surface current densities required for a constant transverse-gradient (a linearly varying magnetic field intensity in a direction transverse to the axis of the cylinder).
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公开(公告)号：EP0051350A3
公开(公告)日：1982-07-21
申请号：EP81303462
申请日：1981-07-28
发明人： Hill, Edwin Roderick
CPC分类号： A61B6/032 , A61B6/06 , A61B6/4233
摘要： A shadowgraphic scanner for producing electronic two-dimensional shadowgraphic images of an examined region of a patient. A source of radiation produces a generally planar beam of radiation which is scanned along the examined region. A two-dimensional array of radiation detectors fixed relative to the source of radiation, but movable in unison therewith relative to the patient. The two-dimensional array of radiation detectors includes a plurality of columns of detectors arranged transverse to the direction in which the beam of radiation is scanned. A first collimator is placed between the source and the patient and a second collimator is placed between the patient and the array of detectors. Both collimators are fixed relative to the source and the detectors and are configured and dimensioned to permit passage therethrough of a beam of radiation of a cross section which corresponds in size to the array of detectors to irradiate the entire array, as the patient is being scanned. Each column of detectors sequentially detects radiation passing through the same section so that a detector from each column contributes sequentially to each section of the examined region. An analog memory cyclically sums the output of each of the columns of radiation detectors in a corresponding plurality of columns of memory units. When a column of memory units has summed the output from each of the columns of detectors, the sum is transferred to an image memory, the memory units in the column zeroed, and the cycle repeated until the entire region of interest is scanned. The data stored in the image memory is displayed on a video monitor.
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