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公开(公告)号：US4931734A
公开(公告)日：1990-06-05
申请号：US336174
申请日：1989-04-11
申请人： Rudolf Kemner , Hilco T. Kalmijn
发明人： Rudolf Kemner , Hilco T. Kalmijn
IPC分类号： G01R33/32 , A61B5/055 , G01R33/341 , H01F7/20
CPC分类号： G01R33/3678
摘要： A quadrature mode rf coil system in a magnetic resonance apparatus includes a pair of orthogonal rf coils which, for excitation and/or detection are coupled to an rf source or receiver by an electronic switching circuit built up from inductances and capacities. The switching circuit includes preferably frequency adjustable 90.degree. first delay lines feeding each coil which transforms the 50.OMEGA. coil impedance of each coil to 100.OMEGA. so that the parallel combination of transformed impedances is 50.OMEGA.. A second 90.degree. delay line is cascaded with the first delay line feeding one of the coils to establish a 90.degree. phase difference between the coils.
摘要翻译： 磁共振装置中的正交模式rf线圈系统包括一对正交rf线圈，用于激励和/或检测通过由电感和容量构成的电子开关电路耦合到rf源或接收器。 开关电路优选地包括频率可调90°的第一延迟线，馈送每个线圈，其将每个线圈的50欧姆线圈阻抗变换为100欧姆，使得变换阻抗的并联组合为50欧姆。 第二个90°延迟线与第一个延迟线级联，馈送一个线圈以在线圈之间建立90°的相位差。
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2.发明授权
公开(公告)号：US4712069A
公开(公告)日：1987-12-08
申请号：US841132
申请日：1986-03-18
申请人： Rudolf Kemner , Hilco T. Kalmijn
发明人： Rudolf Kemner , Hilco T. Kalmijn
CPC分类号： G01R33/3678
摘要： In an apparatus for performing magnetic resonance measurements by means of an orthogonal system of excitation detection coils there is provided a switching circuit for powering and reading the coil system which includes a 1/4 .lambda. coaxial conductor as a connection between the two coil assemblies and a 1/4 .lambda. coaxial conductor with a 90.degree. phase delay as a connection between the first 1/4 .lambda. conductor and the second coil assembly and a detection device. By suitable tuning of the relevant circuit components and the coils, preferably based on 50 Ohms, a simple switching circuit with appropriate matching and phase correction is thus achieved. Specifically, the r.f. power source can be connected to the circuit via an n .lambda. conductor. In the open condition during detection, the n .lambda. conductor represents an infinite impedance for the switching circuit.
摘要翻译： 在用于通过激励检测线圈的正交系统进行磁共振测量的装置中，提供了用于为线圈系统供电和读取的开关电路，该线圈系统包括作为两个线圈组件之间的连接的1/4λ同轴导体和 1/4λ同轴导体，具有90°相位延迟，作为第一1/4λ导体和第二线圈组件之间的连接以及检测装置。 通过适当调谐相关的电路部件和线圈，优选地基于50欧姆，因此实现了具有适当的匹配和相位校正的简单的开关电路。 具体来说，r.f. 电源可以通过nλ导体连接到电路。 在检测期间的开路状态下，nλ导体代表开关电路的无限阻抗。
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公开(公告)号：US4737718A
公开(公告)日：1988-04-12
申请号：US891793
申请日：1986-08-01
IPC分类号： G01R33/3875 , A61B5/055 , A61B10/00 , G01R33/20 , G01R33/34 , G01R33/36 , G01R33/38 , H01F7/20
CPC分类号： G01R33/34076 , G01R33/3628
摘要： Disclosed is a magnetic resonance imaging apparatus, with an r.f. coil which is designed on the basis of the sinusoidal current distribution across a circular-cylindrical surface about a central coil axis and which is, subject to a generally applicable looping-through condition z.sub.1 =-K z.sub.2, when K is a positive constant which depends on the number of bars and geometrical deviations, z.sub.1 is the impedance of the bar conductors, and z.sub.2 is the impedance of ring conductor elements between each two pair of bar conductors. The coil based on the above condition is particularly adapted to parasitic capacitances of the bar conductors and to the general shape of objects to be examined.
摘要翻译： 公开了一种磁共振成像装置，具有r.f. 线圈，其基于围绕中心线圈轴线的圆柱形表面的正弦电流分布而设计，并且其受到通常适用的环通条件z1 = -Kz2的影响，当K是取决于 在条数和几何偏差的数量上，z1是条形导体的阻抗，z2是每两条条形导体之间的环形导体元件的阻抗。 基于上述条件的线圈特别适用于条形导体的寄生电容和被检查物体的一般形状。
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公开(公告)号：US4707662A
公开(公告)日：1987-11-17
申请号：US752281
申请日：1985-07-05
CPC分类号： G01R33/34069 , G01R33/34061 , G01R33/3628
摘要： For increasing the sensitivity of an MR apparatus when measuring comparatively high frequencies, the radio frequency excitation measurement coil (10, 30) is divided into two individual symmetrically drivable and readable coil halves (32, 34), respectively. The mutual connection of central connections of the coil halves can be realized by means of a balun (54) but for this purpose any other symmetrical form of coupling, for example using a strip-line transformer (70) or suitably dimensioned coaxial cables (60, 62) may alternatively be used.
摘要翻译： 为了在测量较高频率时增加MR装置的灵敏度，射频激励测量线圈（10,30）分别被分成两个单独的对称驱动和可读的半导体（32,34）。 线圈半部的中心连接的相互连接可以通过平衡 - 不平衡变压器（54）实现，但为此目的，可以使用任何其它对称形式的耦合，例如使用带状线变压器（70）或适当尺寸的同轴电缆（60） ，62）。
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5.发明授权Picture signal processing circuit for improving high-frequency picture resolution upon picture signal display 失效图像信号处理电路，用于改善图像信号显示的高频图像分辨率
公开(公告)号：US5103219A
公开(公告)日：1992-04-07
申请号：US414808
申请日：1989-09-29
申请人： Rudolf Kemner , Johannes J. Stouten
发明人： Rudolf Kemner , Johannes J. Stouten
摘要： The circuit has an input terminal (1) for supplying a picture signal (CS) formed line and field-sequentially with line and field or frame periods (TV) and an output terminal (2) for supplying a processed picture signal (CS') to be applied to a picture display device (5) comprising a picture display tube operating by way of electron beam scanning (e) of a display screen (8). In the circuit the input terminal (1) is coupled to a filter circuit (10) which has a first output (11) and a second output (12) for supplying a low-frequency (CS.sub.L) or high-frequency (CS.sub.H) picture signal component, respectively. The first output (11) is coupled via an amplifier circuit (16) to a first input (21) of a time-division multiplex circuit (20) having a second input (22) to which the first output (11) and the second output (12) of the filter circuit (10) are coupled each via an amplifier circuit (17, 18) and an adder circuit (19). The time-division multiplex circuit (20) has a switching input (23) which is coupled to an output (29) of a switching signal generator (28) for supplying a periodical switching signal (VS) of the double field or frame period (2TV). An output (24) of the time-division multiplex circuit (20) is coupled to the output terminal (2) of the picture signal processing circuit. The resultant spatial time-division multiplex display yields the improved high-frequency picture resolution.
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6.发明授权X-ray examination apparatus having means for correcting scattered-radiation effects in an x-ray image 失效X射线检查装置具有用于校正X射线图像中的散射辐射效应的装置
公开(公告)号：US5327476A
公开(公告)日：1994-07-05
申请号：US44310
申请日：1993-04-07
申请人： Rudolf Kemner
发明人： Rudolf Kemner
摘要： It is known that perturbations caused by scattered-radiation in an x-ray image can be partially avoided by employing a scattered-radiation grid. A device for further improvement of an x-ray image, in that real-time correction of scattered-radiation effects is achieved, is provided according to the invention. Behind x-ray absorbing parts of the scattered-radiation grid only scattered-radiation appears, whereas both scattered-radiation and primary radiation appear behind transparent channels of the scattered-radiation grid. The scattered-radiation grid gives rise to a high-frequency intensity modulation in the x-ray image. From the high-frequency component of the corresponding video signal produced by the x-ray detector, selection signals are generated by a double pulse generator for distinguishing signal amplitudes of the video signal, corresponding to intensities behind absorbing parts and transparent parts, respectively, of the scattered-radiation grid. The selection signals are supplied to a synchronous detector to split the video signal from the x-ray detector into separated video signals corresponding to scattered-radiation and primary radiation and to scattered-radiation only, respectively. A video signal corresponding to a corrected image is obtained by subtraction of the separated video signals.
摘要翻译： 已知通过使用散射辐射网格可以部分地避免由X射线图像中的散射辐射引起的扰动。 根据本发明提供了一种用于进一步改进X射线图像的装置，其中实现了散射辐射效应的实时校正。 散射辐射网格的X射线吸收部分后面只出现散射辐射，而散射辐射和主辐射两者均散布在散射辐射网格的透明通道之后。 散射辐射网格在x射线图像中产生高频强度调制。 根据由X射线检测器产生的相应视频信号的高频分量，选择信号由双脉冲发生器产生，用于区分视频信号的信号幅度，分别对应于吸收部分和透明部分之后的强度 散射辐射网格。 选择信号被提供给同步检测器，以将来自X射线检测器的视频信号分离成分别对应于散射辐射和初级辐射的分离的视频信号，并且仅分散于散射辐射。 通过减去分离的视频信号获得与校正图像相对应的视频信号。
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7.发明授权Television pick-up and display system suitable for continuous and short-duration information pick-up and for continuous display 失效电视接收和显示系统适用于连续和短时间的信息接收和连续显示
公开(公告)号：US4017679A
公开(公告)日：1977-04-12
申请号：US553541
申请日：1975-02-27
CPC分类号： H04N5/32
摘要： An X-ray television pick-up and display system which is suitable for continuous and short-duration pick-up operation and continuous display. In continuous pick-up operation, in display on a display device an interlaced television picture is composed of two line scanning rasters in a standard manner. In short-duration pick-up operation a synchronizing pulse generator is changed over so that a single line-scanning raster comprising an integral number of lines is obtained for information pick-up, which information is stored in a signal store which for repeated signal supply is connected to the display device. As a result, the picture displayed does not show motional unsharpness and is free from flicker effects.
摘要翻译： X射线电视接收和显示系统，适用于连续和短时间的接收操作和连续显示。 在连续拾取操作中，在显示装置上显示隔行电视图像以标准方式由两行扫描光栅组成。 在短时间拾取操作中，同步脉冲发生器被切换，从而获得包括整数行的单行线扫描光栅用于信息拾取，该信息被存储在用于重复信号提供的信号存储器中 连接到显示设备。 结果，显示的图片不显示动作不清晰度，并且没有闪烁效果。
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公开(公告)号：US6021173A
公开(公告)日：2000-02-01
申请号：US50486
申请日：1998-03-30
IPC分类号： H01L31/09 , G01T1/20 , H01L27/14 , H01L27/146 , H05G1/64
CPC分类号： H01L27/14676 , H01L27/14658
摘要： An x-ray examination apparatus comprises an x-ray detector with a sensor matrix for deriving an image signal from an x-ray image. The x-ray detector is provided with a scatter grid having a regular pattern of x-ray attenuating partitions. The spatial resolution of the sensor matrix is such that the size of the smallest detectable detail in the x-ray image is larger than the distance between adjacent partitions. In particular the x-ray detector comprises an x-ray sensitive photoconductor layer for converting x-rays into electric charges, separate sensor elements include respective collecting electrodes and a semiconductor cladding layer being disposed between the photoconductor layer and the collecting electrodes. The semiconductor cladding layer has a substantial lateral electric conductivity. For example, the semiconductor cladding layer is a chlorine doped selenium layer, or a selenium, sulphur or telluride doped lead-oxide layer.
摘要翻译： X射线检查装置包括具有用于从X射线图像导出图像信号的传感器矩阵的x射线检测器。 X射线检测器设置有具有x射线衰减分区的规则图案的散射格栅。 传感器矩阵的空间分辨率使得x射线图像中最小可检测细节的大小大于相邻分区之间的距离。 特别地，x射线检测器包括用于将x射线转换成电荷的x射线敏感光电导体层，分离的传感器元件包括相应的集电极和设置在光电导体层和收集电极之间的半导体包层。 半导体包覆层具有显着的横向电导率。 例如，半导体包覆层是掺杂氯的硒层，或硒，硫或碲化物掺杂的氧化铅层。
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9.发明授权Television pick-up tube and deflection system for use in such a television pick-up tube 失效电视摄像管和电视摄像机使用的电视摄像系统
公开(公告)号：US5237245A
公开(公告)日：1993-08-17
申请号：US699853
申请日：1991-05-14
申请人： Rudolf Kemner , Pieter Zuidhof
发明人： Rudolf Kemner , Pieter Zuidhof
CPC分类号： H01J29/768
摘要： Accumulation of charge between neighboring image lines can be prevented in a television pick-up tube in which an image pick-up face is scanned along image lines by an electron beam when a comparatively small periodic deflection is imposed on the electron beam in a direction perpendicular to the image lines. To achieve this, a magnetic deflection element in the form of a saddle-shaped coil is disposed between the vertical deflection element of the television pick-up tube and the envelope of the electron gun.
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公开(公告)号：US5006803A
公开(公告)日：1991-04-09
申请号：US31064
申请日：1987-03-26
申请人： Eddy B. Boskamp , Rudolf Kemner
发明人： Eddy B. Boskamp , Rudolf Kemner
CPC分类号： G01R33/3657 , G01R33/341
摘要： For measurements with increased accuracy in a nuclear magnetic resonance apparatus, the detection device is equipped with one or more surface coils which act as measuring coils. To avoid mutual interference between a radio-frequency transmitting coil and the measuring coil, the measuring coil is provided with a decoupling circuit. The surface coil and the decoupling circuit form a part of a tuned circuit which is tuned to a significantly higher natural frequency during activation of the transmitting coil. On the other hand, the transmitting coil is shorted during detection with the surface coil by a low resistance shorting circuit, thereby avoiding interference with the radio-frequency transmission signals.
摘要翻译： 对于在核磁共振装置中具有更高精度的测量，检测装置配备有一个或多个作为测量线圈的表面线圈。 为了避免射频发射线圈与测量线圈之间的相互干扰，测量线圈设有去耦电路。 表面线圈和去耦电路形成调谐电路的一部分，该调谐电路在激励发射线圈期间调谐到显着更高的固有频率。 另一方面，在通过低电阻短路电路与表面线圈的检测期间发送线圈短路，从而避免与射频发送信号的干扰。
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