公开(公告)号：US06236713B1

公开(公告)日：2001-05-22

申请号：US09179805

申请日：1998-10-27

申请人： Richard B. True ,  James C. Taylor ,  Christopher P. Ferrari ,  Curtis G. Allen ,  Thomas M. Bemis

发明人： Richard B. True ,  James C. Taylor ,  Christopher P. Ferrari ,  Curtis G. Allen ,  Thomas M. Bemis

IPC分类号： H01J3514

CPC分类号： H01J35/06 ,  H01J3/12 ,  H01J35/14

摘要： A variable spot size x-ray tube comprises a cathode having an electron emitting surface providing an electron beam that travels essentially along the tube axis of symmetry to an anode. The anode, spaced from the cathode, includes a target, the front surface of which is disposed at an oblique angle with respect to the axis of symmetry. The potential of the anode is generally positive with respect to that of the cathode. The cathode is heated to a temperature at which electrons are emitted by the thermionic emission process. Current from the cathode can be controlled by varying the cathode temperature if the cathode is operated in the temperature limited region. The incident electron beam forms a spot on the target surface whereupon x-rays are produced in response to impingement of the electron beam on the target. The x-rays propagate outwardly from the target spot through a vacuum window to form a beam of x-radiation outside the x-ray tube. An aperture grid is disposed between the cathode and the anode, and has a central aperture permitting the electron beam to pass therethrough. The aperture grid further has a variable voltage applied to it which may be positive, negative, or equal to the potential of the cathode. The voltage on the control grid is used to control the diameter of the electron beam which impinges upon the target. Specifically, the electron beam diameter varies in correspondence with the variable aperture grid voltage, and selective variation of the electron beam diameter results in a corresponding variation in size of the x-ray imaging spot.

摘要翻译： 可变点尺寸x射线管包括具有电子发射表面的阴极，该电子发射表面提供基本上沿着管对称轴线向阳极行进的电子束。 与阴极间隔开的阳极包括靶，其前表面相对于对称轴线倾斜设置。 阳极的电位通常相对于阴极的电位为正。 将阴极加热到通过热离子发射过程发射电子的温度。 如果阴极在温度限制区域中运行，则可以通过改变阴极温度来控制来自阴极的电流。 入射的电子束在目标表面上形成一个点，因此响应于电子束撞击靶而产生X射线。 x射线从靶点向外传播通过真空窗口，以在x射线管外部形成x辐射束。 孔栅格设置在阴极和阳极之间，并且具有允许电子束通过的中心孔。 孔径栅格还具有施加到其上的可变电压，其可以是正的，负的或等于阴极的电位。 控制网格上的电压用于控制撞击目标的电子束的直径。 具体地，电子束直径与可变孔径栅极电压相对应地变化，并且电子束直径的选择性变化导致x射线成像光斑的尺寸的相应变化。

公开(公告)号：US07619224B2

公开(公告)日：2009-11-17

申请号：US11940495

申请日：2007-11-15

申请人： Chiping Chen ,  Thomas M. Bemis ,  Ronak J. Bhatt ,  Jing Zhou

发明人： Chiping Chen ,  Thomas M. Bemis ,  Ronak J. Bhatt ,  Jing Zhou

IPC分类号： H01J49/10 ,  H01J1/50

CPC分类号： G21K5/04 ,  H01J25/60 ,  H01J27/00 ,  H01J37/08 ,  H01J2237/061 ,  H01J2237/063 ,  H01J2237/31701 ,  H05H15/00

摘要： A high-brightness, space-charge-dominated circular charged-particle beam system includes a flat circular emitter that emits charge particles to form a space-charge-dominated circular charged-particle beam. The space-charge-dominated circular charged-particle beam is emitted from the flat circular emitter with a uniform density and having a current emission being space-charge-limited, obeying the Child-Langmuir law. A diode includes at least one electrode at the flat circular emitter and at least one additional electrode that accelerates the charged particles. A beam tunnel is coupled electrically to at least one of the additional electrodes. An applied axisymmetric magnetic field focuses the space-charge-dominated circular charged-particle beam. A depressed collector collects the space-charge-dominated circular charged-particle beam.

摘要翻译： 高亮度，空间电荷主导的圆形带电粒子束系统包括平坦的圆形发射体，其发射电荷粒子以形成空间电荷主导的圆形带电粒子束。 空间电荷主导的圆形带电粒子束从平坦的圆形发射器以均匀的密度发射，并且具有受空间电荷限制的电流发射，符合Child-Langmuir定律。 二极管包括在平坦的圆形发射器处的至少一个电极和加速带电粒子的至少一个附加电极。 光束通道电耦合到附加电极中的至少一个。 应用轴对称磁场聚焦空间电荷主导的圆形带电粒子束。 凹陷式收集器收集以空间电荷为主的圆形带电粒子束。

公开(公告)号：US20080173827A1

公开(公告)日：2008-07-24

申请号：US11940495

申请日：2007-11-15

申请人： Chiping Chen ,  Thomas M. Bemis ,  Ronak J. Bhatt ,  Jing Zhou

发明人： Chiping Chen ,  Thomas M. Bemis ,  Ronak J. Bhatt ,  Jing Zhou

IPC分类号： H01J1/50

CPC分类号： G21K5/04 ,  H01J25/60 ,  H01J27/00 ,  H01J37/08 ,  H01J2237/061 ,  H01J2237/063 ,  H01J2237/31701 ,  H05H15/00

摘要： A high-brightness, space-charge-dominated circular charged-particle beam system includes a flat circular emitter that emits charge particles to form a space-charge-dominated circular charged-particle beam. The space-charge-dominated circular charged-particle beam is emitted from the flat circular emitter with a uniform density and having a current emission being space-charge-limited, obeying the Child-Langmuir law. A diode includes at least one electrode at the flat circular emitter and at least one additional electrode that accelerates the charged particles. A beam tunnel is coupled electrically to at least one of the additional electrodes. An applied axisymmetric magnetic field focuses the space-charge-dominated circular charged-particle beam. A depressed collector collects the space-charge-dominated circular charged-particle beam.

摘要翻译： 高亮度，空间电荷主导的圆形带电粒子束系统包括平坦的圆形发射体，其发射电荷粒子以形成空间电荷主导的圆形带电粒子束。 空间电荷主导的圆形带电粒子束从平坦的圆形发射器以均匀的密度发射，并且具有限制空间电荷的电流发射，符合Child-Langmuir定律。 二极管包括在平坦的圆形发射器处的至少一个电极和加速带电粒子的至少一个附加电极。 光束通道电耦合到附加电极中的至少一个。 应用轴对称磁场聚焦空间电荷主导的圆形带电粒子束。 凹陷式收集器收集以空间电荷为主的圆形带电粒子束。