公开(公告)号：EP1759402B1

公开(公告)日：2015-07-08

申请号：EP05753270.7

申请日：2005-05-20

申请人： Whitehouse, Craig M. ,  Welkie, David G.

发明人： WHITEHOUSE, Craig, M. ,  WELKIE, David, G. ,  COUSINS, Lisa

IPC分类号： H01J49/06 ,  H01J49/42

CPC分类号： H01J49/42 ,  H01J49/062

公开(公告)号：EP2065819A2

公开(公告)日：2009-06-03

申请号：EP08253092.4

申请日：2008-09-22

申请人： Welkie, David G.

发明人： Welkie, David G.

IPC分类号： G06F17/50

CPC分类号： G06F17/13 ,  G06F17/5018 ,  G06F2217/16

摘要： Many important physical phenomena are described by partial differential equations (PDEs) of a function f(x,y,z) constrained by boundary conditions. Solutions of such 'boundary value problems' are often calculated numerically using so-called `finite differences' (FD) methods. Essentially, a regular array, or 'grid', of points is established in the spatial domain, and an array of difference equations are solved numerically to yield values of f(x,y,z) that are consistent with the boundary conditions at the locations of the grid points. However, the boundary conditions are often not initially specified precisely at the locations of grid points, in particular, when such boundary conditions are represented by curved or slanted surfaces which do not coincide precisely with grid point array.
The present invention provides methods by which the values assigned to the boundary grid points are not the values of f(x,y,z) of non-coincident boundary surfaces proximal to the boundary grid points, but rather, values are assigned to the boundary grid points that more accurately account for the differences in locations between each original boundary surface and that of each respective proximal boundary grid point. Consequently, the subject invention provides methods by which the function f(x,y,z) may be calculated with FD methods with greater accuracy than methods. The invention is described herein particularly with regard to solving Laplace's equation to determine potential distributions in electron and/or ion optical devices.

摘要翻译： 许多重要的物理现象由边界条件约束的函数f（x，y，z）的偏微分方程（PDE）描述。 这种“边界值问题”的解决方法通常使用所谓的“有限差分”（FD）方法数值计算。 本质上，在空间域中建立了一个常规数组或“网格”，并以数值方式求解差分方程数组，以产生与边界条件一致的f（x，y，z）值。 网格点的位置。 然而，边界条件通常不是最初在网格点的位置精确地指定，特别是当这种边界条件由与网格点阵列精确地不一致的弯曲或倾斜表面表示时。 本发明提供了分配给边界网格点的值不是接近边界网格点的非重合边界面的f（x，y，z）的值的方法，而是将值分配给边界 网格点更准确地说明每个原始边界表面与每个相应近边界网格点之间的位置差异。 因此，本发明提供了用方法以比方法更精确的方式计算函数f（x，y，z）的方法。 本文描述了本发明，特别是关于求解拉普拉斯方程以确定电子和/或离子光学器件中的电势分布的方法。

公开(公告)号：EP2065819A3

公开(公告)日：2010-02-17

申请号：EP08253092.4

申请日：2008-09-22

申请人： Welkie, David G.

发明人： Welkie, David G.

IPC分类号： G06F17/50

CPC分类号： G06F17/13 ,  G06F17/5018 ,  G06F2217/16

摘要： Many important physical phenomena are described by partial differential equations (PDEs) of a function f(x,y,z) constrained by boundary conditions. Solutions of such 'boundary value problems' are often calculated numerically using so-called `finite differences' (FD) methods. Essentially, a regular array, or 'grid', of points is established in the spatial domain, and an array of difference equations are solved numerically to yield values of f(x,y,z) that are consistent with the boundary conditions at the locations of the grid points. However, the boundary conditions are often not initially specified precisely at the locations of grid points, in particular, when such boundary conditions are represented by curved or slanted surfaces which do not coincide precisely with grid point array.
The present invention provides methods by which the values assigned to the boundary grid points are not the values of f(x,y,z) of non-coincident boundary surfaces proximal to the boundary grid points, but rather, values are assigned to the boundary grid points that more accurately account for the differences in locations between each original boundary surface and that of each respective proximal boundary grid point. Consequently, the subject invention provides methods by which the function f(x,y,z) may be calculated with FD methods with greater accuracy than methods. The invention is described herein particularly with regard to solving Laplace's equation to determine potential distributions in electron and/or ion optical devices.

公开(公告)号：EP1759402A2

公开(公告)日：2007-03-07

申请号：EP05753270.7

申请日：2005-05-20

申请人： Whitehouse, Craig M. ,  Welkie, David G.

发明人： WHITEHOUSE, Craig, M. ,  WELKIE, David, G. ,  COUSINS, Lisa

IPC分类号： H01J49/42

CPC分类号： H01J49/42 ,  H01J49/062

摘要： Apparatus and methods are provided for trapping, manipulation and transferring ions along RF and DC potential surfaces and through RF ion guides. Potential wells are formed neap RF-field generating surfaces due to the overlap of the radio-frequency (RF) fields and electrostatic fields created by static potentials applied to surrounding electrodes. Ions can be constrained and accumulated overtime in such wells. During confinement, ions may be subjected to various processes, such as accumulation, fragmentation, collisional cooling, focusing, mass-to-charge filtering, spatial separation ion mobility and chemical interactions, leading to improved performance in subsequent processing and analysis steps, such as mass analysis. Alternatively, the motion of ions may be better manipulated during confinement to improve the efficiency of their transport to specific locations, such as an entrance aperture into vacuum from atmospheric pressure or into a subsequent vacuum stage.