X-ray examination apparatus having means for correcting
scattered-radiation effects in an x-ray image
    1.
    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

    CPC分类号: H04N5/32 H05G1/60

    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。

    Magnetic resonance apparatus having a quadrature RF coil system
    2.
    发明授权
    Magnetic resonance apparatus having a quadrature RF coil system 失效
    具有正交RF线圈系统的磁共振装置

    公开(公告)号:US4931734A

    公开(公告)日:1990-06-05

    申请号:US336174

    申请日:1989-04-11

    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。

    Television pick-up and display system suitable for continuous and
short-duration information pick-up and for continuous display
    3.
    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。

    Picture signal processing circuit for improving high-frequency picture
resolution upon picture signal display
    4.
    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

    CPC分类号: G06T3/40 H04N5/208

    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.

    Magnetic resonance imaging apparatus including two orthogonal r.f. coils
    5.
    发明授权
    Magnetic resonance imaging apparatus including two orthogonal r.f. coils 失效
    磁共振成像装置包括两个正交的r.f. 线圈

    公开(公告)号:US4712069A

    公开(公告)日:1987-12-08

    申请号:US841132

    申请日:1986-03-18

    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。

    CRT display device comprising a filter in the cathode modulator
    6.
    发明授权
    CRT display device comprising a filter in the cathode modulator 失效
    CRT显示装置包括阴极调制器中的滤光器

    公开(公告)号:US5712538A

    公开(公告)日:1998-01-27

    申请号:US577459

    申请日:1995-12-22

    CPC分类号: H04N9/16

    摘要: A phosphor screen in a display device is scanned by separate electron beams in order to generate images of different frequency content in one color in substantially the same part of the phosphor screen. The different images can be perceived as a composite image for some time. The individual electron beams can be modulated by means of a cathode modulator on the basis of a high frequency and a low frequency component of an electronic image signal or on the basis of an image component and a text component of an electronic image signal. The modulations of the individual electron beams may be slightly delayed relative to one another in order to avoid overloading of the phosphor material.

    摘要翻译: 通过单独的电子束扫描显示装置中的荧光屏,以在荧光屏的基本相同的部分中产生一种颜色的不同频率含量的图像。 不同的图像可以被视为合成图像一段时间。 可以基于电子图像信号的高频和低频分量,或者基于电子图像信号的图像分量和文本分量,借助于阴极调制器来调制各个电子束。 单个电子束的调制可以相对于彼此稍微延迟,以避免荧光体材料的过载。

    X-ray apparatus comprising a filter
    7.
    发明授权
    X-ray apparatus comprising a filter 失效
    包括过滤器的X射线设备

    公开(公告)号:US5625665A

    公开(公告)日:1997-04-29

    申请号:US546027

    申请日:1995-10-20

    IPC分类号: G21K3/00 A61B6/00 G21K1/10

    CPC分类号: G21K1/10

    摘要: 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).

    摘要翻译: X射线装置设置有用于通过物体(3)例如待检查的患者的暴露来限制形成在X射线检测器(4)上的X射线图像的动态范围的滤光器(12) ,到X射线(2)。 过滤器(12)具有包括一个或多个毛细管(13)的过滤元件(13),其一端与储存器与X射线吸收液体连通。 可以通过施加到设置在毛细管(13)的内侧上的导电层的电压来调节X射线吸收液体到毛细管内侧的粘附。 通过电压值调节毛细管(13)与X射线吸收液的填充程度。 通过调整施加到毛细管(13)上的电压,在非常短的时间段(例如1秒钟内)调整X射线吸收曲线。

    Magnetic resonance imaging apparatus including a bird-cage r.f. coil
    8.
    发明授权
    Magnetic resonance imaging apparatus including a bird-cage r.f. coil 失效
    磁共振成像装置,包括鸟笼r.f. 线圈

    公开(公告)号:US4737718A

    公开(公告)日:1988-04-12

    申请号:US891793

    申请日:1986-08-01

    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。

    MR-apparatus having a transmission-measuring coil for high frequencies
    9.
    发明授权
    MR-apparatus having a transmission-measuring coil for high frequencies 失效
    MR装置具有用于高频的传输测量线圈

    公开(公告)号:US4707662A

    公开(公告)日:1987-11-17

    申请号:US752281

    申请日:1985-07-05

    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)。

    Nuclear magnetic resonance tomography apparatus
    10.
    发明授权
    Nuclear magnetic resonance tomography apparatus 失效
    核磁共振断层扫描仪

    公开(公告)号:US4616181A

    公开(公告)日:1986-10-07

    申请号:US539581

    申请日:1983-10-06

    摘要: The transmitter/measurement coil of a nuclear magnetic resonance tomography apparatus for medical diagnosis in which comparatively high Larmor frequencies are used, is divided into a number of parallel-connected subcoils. The self resonance frequency of the coil can thus be made substantially higher than the Larmor frequency, with the result that the coil will have a suitably improved quality factor at higher frequencies, and measurements can be performed with an acceptable signal-to-noise ratio.

    摘要翻译: 用于医疗诊断的核磁共振断层摄影装置的发射器/测量线圈,其使用相对较高的拉莫尔频率,被分成多个并联连接的次线圈。 因此,线圈的自谐振频率可以大大高于拉莫尔频率,结果线圈将在较高频率下具有适当改善的品质因数,并且可以以可接受的信噪比进行测量。