公开(公告)号：US5193105A

公开(公告)日：1993-03-09

申请号：US809924

申请日：1991-12-18

Applicant: Roy E. Rand ,  Eugene Y. Tsiang

Inventor： Roy E. Rand ,  Eugene Y. Tsiang

IPC: H01J35/04

CPC classification number: H01J35/04

Abstract: An electron beam scanning system employing a relatively short housing chamber wherein an electron beam is produced includes an ion controlling electrode assembly. Located in the housing between the electron gun and system beam optics, the assembly includes a generally cone-shaped rotating field ion controlling electrode (or "RICE") unit comprising cylindrically symmetrical element pairs disposed on opposite sides of the housing Z-axis. Preferably equal and opposite potential sources coupled to elements comprising an element pair create a transverse electric field therebetween. The vector sum of the fields produced by all element pairs is the transverse field created by the RICE unit. The potentials are varied, rotating the overall RICE field to controllably remove most but not all positive ions. The remaining ions improve the electron beam space-charge density, resulting in a sharply focused scanning electron beam. Preferably a disk-like positive ion electrode (or "PIE") unit coupled to a large positive potential is disposed downstream from the RICE unit to block upstream migration of positive ions. Where discontinuities are present in the housing, a periodic axial field ion controlling electrode (or "PICE") unit is disposed at the upstream end of the overall assembly. The PICE comprises spaced-apart disks alternately coupled to large and small potentials to create alternating axial fields within a short axial distance, to rapidly sweep away ions. Regions within the overall assembly not otherwise acted upon by fields are covered with one or more conventional ICE units to sweep away positive ions.

Abstract translation: 采用其中产生电子束的相对较短的壳体室的电子束扫描系统包括离子控制电极组件。 位于电子枪和系统光束光学器件之间的壳体中，组件包括大致锥形的旋转场离子控制电极（或“RICE”）单元，其包括设置在壳体Z轴的相对侧上的圆柱对称元件对。 优选地，耦合到包括元件对的元件的相等和相反的电位源在它们之间产生横向电场。 由所有元素对产生的场的矢量和是由RICE单元创建的横向场。 电位变化，旋转整个RICE领域可控制地去除大部分但不是全部的正离子。 剩余的离子可以改善电子束的空间电荷密度，从而产生清晰的扫描电子束。 优选地，耦合到大正电位的盘状正离子电极（或“PIE”）单元设置在RICE单元的下游以阻止正离子的上游迁移。 在壳体中存在不连续性的情况下，周期性轴向场离子控制电极（或“PICE”）单元设置在整个组件的上游端。 PICE包括交替地耦合到大的和小的电位的间隔开的盘，以在短的轴向距离内产生交替的轴向场，以快速地扫除离子。 整个组件内的区域不是由场所影响的区域被一个或多个常规的ICE单元覆盖以扫除正离子。

公开(公告)号：US4625150A

公开(公告)日：1986-11-25

申请号：US600464

申请日：1984-04-16

Applicant: Roy E. Rand

Inventor： Roy E. Rand

IPC: H01J3/40 ,  H01J35/14 ,  H01J29/84

CPC classification number: H01J35/14 ,  H01J3/40

Abstract: An improved ion clearing electrode assembly for use in an electron beam production and control assembly which is especially suitable for use in a scanning electron beam computed tomography X-ray scanning system. The assembly uses a vacuum sealed housing chamber which is evacuated of internal gases and in which the electron beam is generated and propagated. Normally residual gas within the chamber interacts with the electrons of the beam to produce positive ions which have the affect of neutralizing the space charge of the electron beam and thereby causing focusing difficulties and destabilization of the beam. The ion collecting electrodes herein are an improvement of those disclosed in the co-pending Rand U.S. patent application Ser. No. 434,252, now U.S. Pat. No. 4,521,900. The electrodes are designed to extract the ions and reduce their neutralizing effect while maintaining a precisely uniform electric field and therefore beam optical aberrations are minimized. In addition, the electrode provides flexibility in the variation of parameters which effect ion extraction and the neutralization fraction.

Abstract translation: 一种用于电子束生产和控制组件的改进的离子清除电极组件，其特别适用于扫描电子束计算机断层摄影X射线扫描系统。 组件使用真空密封的容纳室，其被内部气体排空，并且其中电子束被产生和传播。 通常，室内的残余气体与光束的电子相互作用以产生具有中和电子束的空间电荷的影响的正离子，从而引起聚焦困难和光束的不稳定性。 本文中的离子收集电极是共同未决的兰德美国专利申请系列公开的那些的改进。 现在的美国专利第434,252号。 第4,521,900。 电极被设计成提取离子并降低它们的中和效应，同时保持精确均匀的电场，并且因此光束像差最小化。 此外，电极提供影响离子提取和中和分数的参数变化的灵活性。

公开(公告)号：US07020232B2

公开(公告)日：2006-03-28

申请号：US10371467

申请日：2003-02-21

Applicant: Roy E. Rand ,  Jonathan Harman ,  Douglas P. Boyd

Inventor： Roy E. Rand ,  Jonathan Harman ,  Douglas P. Boyd

IPC: H05G1/60

CPC classification number: A61B6/032 ,  A61B6/027 ,  A61B6/4028 ,  A61B6/4085 ,  G01N23/046 ,  G01N2223/419 ,  G01N2223/612 ,  G06T11/005 ,  G06T2211/428 ,  G21K1/06

Abstract: A scanning electron beam computed tomographic system eliminates axial offset between target and detector by disposing the target, collimator, and detector such that active portions of the target and detector are always diametrically opposite each other. This result is achieved by providing a helical target, collimator, and detector, or by providing planar target, collimator, and detector components that are inclined relative to the vertical axis such that active portions of the target and detector are always diametrically opposite each other. Either configuration eliminates cone beam error and the necessity to correct for same. Further, the system can provide multi-slice scanning of an object that is in constant motion at a critical velocity, without having to interpolate data. Conventional helical scanning may still be undertaken. Detector elements can be disposed axially to improve signal/noise ratio and to produce a cone beam cancellation effect.

Abstract translation: 扫描电子束计算机断层摄影系统通过设置目标，准直仪和检测器来消除目标和检测器之间的轴向偏移，使得目标和检测器的有效部分总是沿径向相反。 该结果通过提供螺旋靶，准直器和检测器，或者通过提供相对于垂直轴线倾斜的平面靶，准直器和检测器部件来实现，使得靶和检测器的有效部分总是沿直径相对。 任何一种配置都可以消除锥形光束误差，同时也需要进行校正。 此外，该系统可以以临界速度提供恒定运动的物体的多层扫描，而无需内插数据。 传统的螺旋扫描可能仍然可以进行。 检测器元件可以轴向布置以改善信号/噪声比并产生锥形束消除效果。

公开(公告)号：US06792077B2

公开(公告)日：2004-09-14

申请号：US10064182

申请日：2002-06-19

Applicant: Roy E. Rand

Inventor： Roy E. Rand

IPC: G21K102

CPC classification number: A61B6/4028 ,  A61B6/032 ,  A61B6/06 ,  A61B6/4085 ,  G21K1/025

Abstract: An electron beam tomography (EBT) scanning system comprising an electron source generating an electron beam, a target ring that receives the electron beam and emits an x-ray fan beam upon impingement of the electron beam on the target ring, a pair of detector arrays arranged opposite the target ring, and a collimator arranged concentrically between the target ring and the pair of detector arrays. The collimator has interior and exterior walls concentrically arranged with one another and surrounding a patient examination area. The interior and exterior walls have a first set of apertures aligned to collimate the x-ray fan beam into a first collimated beam having a first width and a second collimated beam having a second width. Each collimated beam may form a single or double tomographic slice. The collimated beams are detected by the pair of detector arrays.

Abstract translation: 包括产生电子束的电子源的电子束层析成像（EBT）扫描系统，接收电子束并在电子束撞击目标环时发射X射线扇形束的目标环，一对检测器阵列 与目标环相对设置的准直器和同心地布置在目标环和该对检测器阵列之间的准直器。 准直器具有彼此同心地布置并且围绕患者检查区域的内部和外部壁。 内壁和外壁具有第一组孔，其对准以将X射线扇形光束准直成具有第一宽度的第一准直光束和具有第二宽度的第二准直光束。 每个准直光束可以形成单层或双层断层切片。 准直光束由一对检测器阵列检测。

公开(公告)号：US6160869A

公开(公告)日：2000-12-12

申请号：US165244

申请日：1998-10-01

Applicant: Geordie Zapalac ,  Roy E. Rand

Inventor： Geordie Zapalac ,  Roy E. Rand

IPC: H01J35/14 ,  H01J35/30

CPC classification number: H01J35/30 ,  H01J35/14

Abstract: Tuning, integrating, and operating an electron beam CT scanning system is simplified by using the fringe field from dipole magnets arranged as a chicane to focus the electron beam, thus replacing conventional quadrupole and solenoid coils. Preferably four "chicane" dipole magnets are series-coupled with the windings in the downstream deflection magnet, such that the chicane magnet X and Y coils are energized 90.degree. out of phase with the deflection magnet coils. The alternating current polarity in the chicane magnets creates an "S"-shaped electron beam trajectory that adequately uniformly focuses over the full cross-section of the electron beam. Winding the coils with a cosine distribution permits rotating the magnetic fields to change the azimuthal and deflecting planes of the electron beam, without disturbing the deflection angle and focusing properties. Chicane electrical current directions and magnet positions are such that the electron beam enters and exists the chicane on the axis of the scanning electron beam CT system. A new type of deflecting magnet is provided that has no end windings, and may be used in other beam optical systems.

Abstract translation: 通过使用布置为拐角的偶极磁体的边缘场来聚焦电子束，从而简化了电子束CT扫描系统的调谐，积分和操作，从而取代了传统的四极和螺线管线圈。 优选地，四个“拐角”偶极子磁体与下游偏转磁体中的绕组串联耦合，使得拐角磁体X和Y线圈与偏转磁体线圈相位90°异相。 拐角磁体中的交流极性产生了一个“S”形的电子束轨迹，足以使电子束的整个横截面均匀地聚焦。 用余弦分布卷绕线圈允许旋转磁场以改变电子束的方位角和偏转平面，而不会干扰偏转角和聚焦性质。 奇烷电流方向和磁体位置使得电子束在扫描电子束CT系统的轴线上进入并存在拐角。 提供了一种新型的偏转磁体，其不具有端部绕组，并且可用于其它光束光学系统。

公开(公告)号：US06735271B1

公开(公告)日：2004-05-11

申请号：US09728481

申请日：2000-11-28

Applicant: Roy E. Rand ,  Jonathan Harman ,  Douglas P. Boyd

Inventor： Roy E. Rand ,  Jonathan Harman ,  Douglas P. Boyd

IPC: H05G160

CPC classification number: A61B6/032 ,  A61B6/027 ,  A61B6/4028 ,  A61B6/4085 ,  G01N23/046 ,  G01N2223/419 ,  G01N2223/612 ,  G06T11/005 ,  G06T2211/428 ,  G21K1/06

Abstract: A scanning electron beam computed tomographic system eliminates axial offset between target and detector by disposing the target, collimator, and detector such that active portions of the target and detector are always diametrically opposite each other. This result is achieved by providing a helical target, collimator, and detector, or by providing planar target, collimator, and detector components that are inclined relative to the vertical axis such that active portions of the target and detector are always diametrically opposite each other. Either configuration eliminates cone beam error and the necessity to correct for same. Further, the system can provide multi-slice scanning of an object that is in constant motion at a critical velocity, without having to interpolate data. Conventional helical scanning may still be undertaken. Detector elements can be disposed axially to improve signal/noise ratio and to produce a cone beam cancellation effect.

Abstract translation: 扫描电子束计算机断层摄影系统通过设置目标，准直仪和检测器来消除目标和检测器之间的轴向偏移，使得目标和检测器的有效部分总是沿径向相反。 该结果通过提供螺旋靶，准直器和检测器，或者通过提供相对于垂直轴线倾斜的平面靶，准直器和检测器部件来实现，使得靶和检测器的有效部分总是沿直径相对。 任何一种配置都可以消除锥形光束误差，同时也需要进行校正。 此外，该系统可以以临界速度提供恒定运动的物体的多层扫描，而无需内插数据。 传统的螺旋扫描可能仍然可以进行。 检测器元件可以轴向布置以改善信号/噪声比并产生锥形束消除效果。

公开(公告)号：US06208711B1

公开(公告)日：2001-03-27

申请号：US09399910

申请日：1999-09-21

Applicant: Roy E. Rand ,  Khem Garewal ,  James F. Heilman

Inventor： Roy E. Rand ,  Khem Garewal ,  James F. Heilman

IPC: H01J3514

CPC classification number: G21K1/08 ,  A61B6/032 ,  A61B6/4028 ,  H01J35/02

Abstract: In a scanning electron beam CT system, a positive ion clearing electrode system is disposed within the CT system solenoid coil, and is operated from a single power source. Mounted coaxially about the electron beam, preferably the electrode system includes three sections, each having two electrode elements, one element being coupled to about −800 V to about −2 kV and the other element being grounded. Within the electrode system, the ratio between element diameter and electron beam diameter is substantially constant. Preferably elements are helically twisted about the beam axis. The electrode configuration cancels net quadrupole (focusing) and octopole (aberration-producing) fields. In the presence of electric discharge, essentially zero electron beam displacement and deflections occurs, and changes in focusing strength remain zero.

Abstract translation: 在扫描电子束CT系统中，正离子清除电极系统设置在CT系统螺线管线圈内，并从单个电源操作。 优选地，电极系统包括三个部分，每个部分具有两个电极元件，一个元件耦合到大约-800V至大约-2kV，另一个元件接地。 在电极系统内，元件直径与电子束直径之间的比率基本上是恒定的。 优选地，元件围绕光束轴线螺旋扭曲。 电极配置消除了净四极（聚焦）和八极（产生像差）场。 在放电的情况下，发生基本为零的电子束位移和偏转，并且聚焦强度的变化保持为零。

公开(公告)号：US5442673A

公开(公告)日：1995-08-15

申请号：US220076

申请日：1994-03-30

Applicant: Roy E. Rand ,  Patrick B. Halahan

Inventor： Roy E. Rand ,  Patrick B. Halahan

IPC: A61B6/03 ,  A61B6/02

CPC classification number: A61B6/4028 ,  A61B6/032

Abstract: An x-ray collimator is described which is useful in an electron beam (EB) computed tomography (CT) scanner of the type in which a rotating electron beam is directed to impinge upon a ring-shaped target and the x-rays generated in response thereto are directed to a ring shaped detector array spaced therefrom. The collimator consists of an x-ray blocking septum having an aperture therein, the septum being located in a fixed position substantially co-planer with the planes of the target and the detector, so as to block all x-rays directed from said target to said detector except those which pass through said aperture. Tomographic slice width is determined by the "view" from the spot where the electron beam impinges upon the target, through the aperture, to the detector, and is variable by adjusting the position where the electron beam impinges upon the width of the x-ray target, and in a preferred embodiment, the position of a movable ring. In the preferred embodiment, a movable ring is provide which has a longitudinal axis positioned coaxial with the axis of the aperture and an end face opposed to and parallel with the septum. As well as forming part of the collimator, this ring acts as a pre-collimation radiation shield. This ring is moved concurrently when moving the position where the electron beam impinges upon the width of the x-ray target when the tomographic slice width is varied, by adjusting the spacing between the end face of the moveable ring and the septum.

Abstract translation: 描述了一种在电子束（EB）计算机断层摄影（CT）扫描器中有用的X射线准直仪，其中旋转电子束被引导撞击环形目标，并且响应中产生的x射线 其指向与其间隔开的环形检测器阵列。 准直器由在其中具有孔的x射线阻挡隔膜组成，隔膜位于与目标和检测器的平面基本上共同平面的固定位置，以便阻挡从所述目标指向的所有X射线 所述检测器除了通过所述孔的那些。 断层切片宽度由电子束通过孔径撞击到检测器的点处的“视图”确定，并且可以通过调节电子束在x射线的宽度上照射的位置而变化 目标，并且在优选实施例中，可移动环的位置。 在优选实施例中，提供可移动环，其具有与孔的轴线同轴的纵向轴线和与隔膜相对并平行的端面。 除了形成准直器的一部分之外，该环还用作预准直辐射屏蔽。 当通过调节活动环的端面与隔膜之间的间隔来改变断层切片宽度变化时，当移动电子束照射在x射线靶的宽度上的位置时，该环同时移动。

公开(公告)号：US06670625B1

公开(公告)日：2003-12-30

申请号：US10064174

申请日：2002-06-18

Applicant: Roy E. Rand ,  Khem Garewal

Inventor： Roy E. Rand ,  Khem Garewal

IPC: G01N2300

CPC classification number: G21K1/087

Abstract: A method and apparatus are disclosed for reducing variation in a spot size of an electron beam at a target due to multipole aberrations in an electron beam tomography (EBT) scanner. A magnitude of a DC voltage applied to a positive ion electrode (PIE) within the EBT scanner is adjusted and an orientation of a non-circular aperture of the PIE is aligned with respect to the electron beam. A profile of the spot size is monitored while adjusting the magnitude of the DC voltage and while aligning the orientation of the non-circular aperture of the PIE until the variation in the spot size is sufficiently reduced.

Abstract translation: 公开了一种用于减少由于电子束层析成像（EBT）扫描仪中的多极像差导致的目标处的电子束的斑点尺寸变化的方法和装置。 调整施加到EBT扫描仪内的正离子电极（PIE）的DC电压的大小，并且PIE的非圆形孔径的取向相对于电子束对准。 在调整直流电压的大小并同时对齐PIE的非圆形孔径的方向直到光斑尺寸的变化充分降低时，监测光斑尺寸的轮廓。

公开(公告)号：US5491734A

公开(公告)日：1996-02-13

申请号：US167419

申请日：1993-12-14

Applicant: Douglas P. Boyd ,  Roy E. Rand

Inventor： Douglas P. Boyd ,  Roy E. Rand

IPC: H05G2/00 ,  A61B6/03 ,  H01J35/24 ,  H05G1/26 ,  H05G1/60

CPC classification number: H05G1/26 ,  A61B6/032 ,  A61B6/4028 ,  H01J35/24

Abstract: A scanning electron beam CT system generates an electron beam along a beam source axis offset from the scanner axis, or axis of symmetry, thereby permitting the X-ray subject to pass completely through the stationary gantry. The electron beam is produced with the first drift tube region of an evacuated housing chamber, and is directed downstream toward a second region that includes a gantry. A scan target and a tuning target, each concentric with and defining a plane normal to the system axis of symmetry, are located in the gantry. A beam optics system, through which the electron beam passes, is located within the housing intermediate the electron gun and gantry. A control system focusses and scans the electron beam upon the scan target, maintaining a beam spot of desired quality. Upon impingement by the scanning beam spot, the scan target emits a fan beam of X-rays. A detector array, concentric with and defining a plane normal to the system axis of symmetry, is located opposite the scan target within the gantry and provides output signals that are computer processed to reconstruct a CT image of a subject placed within the gantry. The scanner axis is preferably above the beam source axis, and preferably the drift tube is straight, defining a drift tube axis that is inclined relative to the scanner axis, or is parallel to the scanner axis but not co-axial therewith. Alternatively, the drift tube may be kinked.

Abstract translation: 扫描电子束CT系统沿着从扫描器轴线或对称轴偏移的光束源轴产生电子束，从而允许X射线物体完全通过固定台架。 电子束由抽真空的容纳室的第一漂移管区域产生，并且被引向下游朝向包括台架的第二区域。 扫描目标和调谐目标，每个同心于并定义与系统对称轴垂直的平面，位于台架中。 电子束通过的光束系统位于电子枪和龙门架内部的壳体内。 控制系统将电子束聚焦并扫描到扫描目标上，保持所需质量的光点。 在被扫描光束点撞击时，扫描目标发射X射线的风扇束。 检测器阵列同心于并限定垂直于系统对称轴的平面，与机架内的扫描目标相对，并提供计算机处理的输出信号，以重建放置在机架内的被摄体的CT图像。 扫描器轴优选地在波束源轴线上方，并且优选地，漂移管是直的，限定相对于扫描器轴线倾斜或者平行于扫描器轴线但不与其同轴的漂移管轴线。 或者，漂移管可以扭结。