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US4736106A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for uniform charged particle irradiation of a surface

Assignee: Michigan State University
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Filing: 1986-10-08
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Granted: 1988-04-05
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Expires: 2006-10-08
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Abstract

Abstract A method and apparatus which uses combined quadrupole (Qx and Qy) and multipole magnet sets (Mx and My) to focus a charged particle beam from a point source is described. Primarily the multipole magnet sets are octupole magnets. The apparatus is particularly useful for providing a uniform intensity for ion implantation, in cancer therapy and in other fields where uniform charged particle irradiation of a surface is important.

Inventors

  • 👤 Edwin Kashy
  • 👤 Bradley M. Sherrill

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 04:43
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/02; H01J37/04; H01J37/10; H01J37/14; H01J37/141; A; A61; A61N; A61N5/00; A61N5/10; G; G21; G21K; G21K1/00; G21K1/08; G21K1/093; H01J37/30; H01J37/317; H01J37/3171; A61N2005/1085; A61N2005/1087; H01J2237/00; H01J2237/153

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 199 words
A magnetic optical beam homogenizing and focussing apparatus for charged particle beams which comprises: (a) holder means which mounts on a source of accelerated charged particles which are scattered outward in a gaussian-like angular distribution from a longitudinal axis from the source, wherein a X and a Y axis are defined perpendicular to the longitudinal axis; (b) beam trnsport magnetic lens sets positioned on the holder means around the longitudinal axis, such that the charged particles are focussed towards and cross the longitudinal axis to define a focal area on the axis wherein the focal area of the beam viewed on the X axis is at a different part of the longitudinal axis than the focal area of the beam viewed on the Y axis; and (c) at least two multipole magnet sets each having at least 6 poles mounted on the holder means around the longitudinal axis at each of the focal areas on the X and Y axis, wherein the multipole magnet sets depending upon the number of poles, make specific changes to the direction of the particles according to the position of the particles within the multipole magnet sets to thereby homogenize and focus the beam.
Claim 2
Dependent Claim 199 words
A magnetic optical beam homogenizing and focussing apparatus for charged particle beams which comprises: (a) holder means which mounts on a source of accelerated charged particles which are scattered outward in a gaussian-like angular distribution from a longitudinal axis from the source, wherein a X and a Y axis are defined perpendicular to the longitudinal axis; (b) beam trnsport magnetic lens sets positioned on the holder means around the longitudinal axis, such that the charged particles are focussed towards and cross the longitudinal axis to define a focal area on the axis wherein the focal area of the beam viewed on the X axis is at a different part of the longitudinal axis than the focal area of the beam viewed on the Y axis; and (c) at least two multipole magnet sets each having at least 6 poles mounted on the holder means around the longitudinal axis at each of the focal areas on the X and Y axis, wherein the multipole magnet sets depending upon the number of poles, make specific changes to the direction of the particles according to the position of the particles within the multipole magnet sets to thereby homogenize and focus the beam.
Claim 3
Dependent Claim 18 words
The method of claim 1 wherein each of the multipole magnet sets have between 6 and 20 poles.
Claim 4
Dependent Claim 15 words
The apparatus of claim 1 wherein each of the multipole magnet sets have 8 poles.
Claim 5
Independent Claim 216 words
A method for homogenizing and focussing a beam of charged particles on a surface to be irradiated which comprises: (a) providing a holder means mounted on a point source of accelerated charged particles which are scattered outward in a gaussian angular distribution from a longitudinal axis from the source wherein a X and a Y axis are defined perpendicular to the logitudinal axis; beam transport magnetic lens sets positioned on the holder means around the longitudinal axis, such tha the charged particles are focussed towards and cross the longitudinal axis to define a focal area on the axis wherein the focal area of the beam viewed on the X axis is at a different part of the longitudinal axis than the focal area of the beam viewed on the Y axis; and at least two multipole magnet sets having at least 6 poles mounted on the holder means around the longitudinal axis at each of the focal areas on the X and Y axis, wherein the multipole magnet sets depending upon the number of poles, make specific changes to the direction of the particles according to the position of the particles within the multipole magnet sets to thereby homogenize and focus the beam; (b) providing the homogenized and focussed beam on the surface to be irradiated.
Claim 6
Independent Claim 216 words
A method for homogenizing and focussing a beam of charged particles on a surface to be irradiated which comprises: (a) providing a holder means mounted on a point source of accelerated charged particles which are scattered outward in a gaussian angular distribution from a longitudinal axis from the source wherein a X and a Y axis are defined perpendicular to the logitudinal axis; beam transport magnetic lens sets positioned on the holder means around the longitudinal axis, such tha the charged particles are focussed towards and cross the longitudinal axis to define a focal area on the axis wherein the focal area of the beam viewed on the X axis is at a different part of the longitudinal axis than the focal area of the beam viewed on the Y axis; and at least two multipole magnet sets having at least 6 poles mounted on the holder means around the longitudinal axis at each of the focal areas on the X and Y axis, wherein the multipole magnet sets depending upon the number of poles, make specific changes to the direction of the particles according to the position of the particles within the multipole magnet sets to thereby homogenize and focus the beam; (b) providing the homogenized and focussed beam on the surface to be irradiated.
Claim 7
Dependent Claim 18 words
The method of claim 4 wherein each of the multipole magnet sets have between 6 to 20 poles.
Claim 8
Dependent Claim 15 words
The method of claim 3 wherein each of the multipole magnet sets have 8 poles.

References Cited (Backward Citations)

US3028491A Cited
US3482136A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-04-05 1991-10-05 1992-04-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-04-05 1995-10-05 1996-04-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-04-05 1999-10-05 2000-04-05 $7700.00 Window Closed / Lapsed

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