CA1088221A - Electron accelerator - Google Patents
Electron acceleratorInfo
- Publication number
- CA1088221A CA1088221A CA286,193A CA286193A CA1088221A CA 1088221 A CA1088221 A CA 1088221A CA 286193 A CA286193 A CA 286193A CA 1088221 A CA1088221 A CA 1088221A
- Authority
- CA
- Canada
- Prior art keywords
- compensating
- target
- compensating member
- cone
- base
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H6/00—Targets for producing nuclear reactions
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
- G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
- G21K1/10—Scattering devices; Absorbing devices; Ionising radiation filters
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J35/00—X-ray tubes
- H01J35/02—Details
- H01J35/04—Electrodes ; Mutual position thereof; Constructional adaptations therefor
- H01J35/08—Anodes; Anti cathodes
- H01J35/112—Non-rotating anodes
- H01J35/116—Transmissive anodes
Landscapes
- Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
- Engineering & Computer Science (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Optics & Photonics (AREA)
- Plasma & Fusion (AREA)
- General Engineering & Computer Science (AREA)
- Radiation-Therapy Devices (AREA)
- X-Ray Techniques (AREA)
- Particle Accelerators (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
In an electron accelerator having a target which is exposed to an electron beam for the production of x-ray deceleration radiation, a conical compensating member is arranged centrally within a cone pattern of the x-ray radiation. The compensating member has a decreasing conical shape toward the target and merges into a cylinder portion. Beam paths within the cylinder portion which are additional to those in a conventional purely conical compensating member are compensated by a recess positioned in a base of the compensating member having an appropriately selected depth, In another embodiment, a conically shaped compensating member is arranged within the cone-shaped x-ray pattern such that a tip of the compensating member is aligned away from the target and a base is aligned toward the target. A collimator having a conical passageway surrounding the x-ray radiation has a groove for receiving the base of the compensating member so as to mount the same within the conical passageway of the collimator.
In an electron accelerator having a target which is exposed to an electron beam for the production of x-ray deceleration radiation, a conical compensating member is arranged centrally within a cone pattern of the x-ray radiation. The compensating member has a decreasing conical shape toward the target and merges into a cylinder portion. Beam paths within the cylinder portion which are additional to those in a conventional purely conical compensating member are compensated by a recess positioned in a base of the compensating member having an appropriately selected depth, In another embodiment, a conically shaped compensating member is arranged within the cone-shaped x-ray pattern such that a tip of the compensating member is aligned away from the target and a base is aligned toward the target. A collimator having a conical passageway surrounding the x-ray radiation has a groove for receiving the base of the compensating member so as to mount the same within the conical passageway of the collimator.
Description
~0~822~
The invention relates to an electron accelerator comprising a targe~ exposed to an electron beam for the production o x-ray deceleration radiation and also comprising a massive cone-shaped compensating member which is centrally arranged in the x-ray cone.
Tn the case of electron accelerators x-ray deceleration radiation is produced due to a deceleration of the electrons in a so-called target. It -is kno~n in the art to balance or compensate the dosage in a gi~en space-angle range o the x-rays leaving the target by placing a compnesating member into the portion of the x-ray cone of interest. This compensating member has a conical design. Its contour path is adapted to the path of the radiation in-tensity at the place of use. Since the dosage decreases very markedly with the distance from the center beam behind the target, the sides of the compen-sating member are correspondinglyisteep and thè tip of the compensating member must be positioned very precisely with respect to the center beam.
In the case of a properly employed compensating member, the generally conlcal intensity distribution which would be assumed by the beam cone leaving the target at the location plane of a patient undergoing treatment would be changed so as to ha~e a flat central portion. The compen- ~`
sating member absorbs the overly intense radiation in the center as-compared with the margins of a given beam cone. The portion of the beam having the flat intensity distribution can be used for radiation purposes. It is a disadvantage, therefore, that, even for exact positioning, misadjustments of dose compensation can occur due to minor fluctuations of the direction of the electron beam leaving the accelerator.
In order to decrease the difficulties encountered by adjustement of the compensating member, it has been previously suggested to place the com-pensating member further away from the target in a range of the beam cone where the latter has already clearly widened. This, however, has the dis-advantage that the compensating member is then arranged closer to the patient.
Also, a -portion of the beam which scatters unavoidably in the compensating member along ~lth its source, has also been placed closer to the patient. Due to the square distance law, this causes an increased radiation stress for the patient even with a relatively low-energy beam component. Furthermore, due to the increase of the spacing between the compensating member and the target, the entire beam defining system becomes larger and hea~ier.
. ~t is an object o~ this invention to pro~ide a means of compensating ~ -the dosage distribution in the useful portions of the x-ray cone such that the alignment o the compensating member to the center beam is less critical.
~n the case of an electron accelerator of this invention, the com-pensating member decreases conically. Its decreased portion merges into a cylinder such that the partial beam paths which are also in the cylinder por-tion of the compensating member (as compared with the purely conical embodi-ment) are compensated by a recess provided in the base of the compensating member having an appropriate local depth. It thus results that the end of ;
the compensating member which is turned towards the radiation source is blunt and thus less~sensitive to alignment errors. The portions with strong changes of the absorption values are placed into a place perpendicular to the :
beam direction at a greater distance from the ocal point and thus into an 20 area where the beam cone has-already widened to a greater extent. ;
; A further reduction of the preciseness with which the compensating member must be aligned in the beam cone is obtained when, in a further develop-ment of the invention, the front surface of the cylindrical portion of the compensating member turned towards the target has its margins rounded and ; the outer portion of the recess is slightly distorted outwardly at the base of the compensating member in order to compensate the absorption. Thus, the alignment of the compensating member becomes less critical, including that ~ ;
range of the beam cone which corresponds to the margin of the upper frontal surface of the cylindrical portion.
Thus, ln accordance ~lth one aspect of the in~ention, there is pro~ided an-electron accèlerator comprlsing:
(a) an electron beam;
The invention relates to an electron accelerator comprising a targe~ exposed to an electron beam for the production o x-ray deceleration radiation and also comprising a massive cone-shaped compensating member which is centrally arranged in the x-ray cone.
Tn the case of electron accelerators x-ray deceleration radiation is produced due to a deceleration of the electrons in a so-called target. It -is kno~n in the art to balance or compensate the dosage in a gi~en space-angle range o the x-rays leaving the target by placing a compnesating member into the portion of the x-ray cone of interest. This compensating member has a conical design. Its contour path is adapted to the path of the radiation in-tensity at the place of use. Since the dosage decreases very markedly with the distance from the center beam behind the target, the sides of the compen-sating member are correspondinglyisteep and thè tip of the compensating member must be positioned very precisely with respect to the center beam.
In the case of a properly employed compensating member, the generally conlcal intensity distribution which would be assumed by the beam cone leaving the target at the location plane of a patient undergoing treatment would be changed so as to ha~e a flat central portion. The compen- ~`
sating member absorbs the overly intense radiation in the center as-compared with the margins of a given beam cone. The portion of the beam having the flat intensity distribution can be used for radiation purposes. It is a disadvantage, therefore, that, even for exact positioning, misadjustments of dose compensation can occur due to minor fluctuations of the direction of the electron beam leaving the accelerator.
In order to decrease the difficulties encountered by adjustement of the compensating member, it has been previously suggested to place the com-pensating member further away from the target in a range of the beam cone where the latter has already clearly widened. This, however, has the dis-advantage that the compensating member is then arranged closer to the patient.
Also, a -portion of the beam which scatters unavoidably in the compensating member along ~lth its source, has also been placed closer to the patient. Due to the square distance law, this causes an increased radiation stress for the patient even with a relatively low-energy beam component. Furthermore, due to the increase of the spacing between the compensating member and the target, the entire beam defining system becomes larger and hea~ier.
. ~t is an object o~ this invention to pro~ide a means of compensating ~ -the dosage distribution in the useful portions of the x-ray cone such that the alignment o the compensating member to the center beam is less critical.
~n the case of an electron accelerator of this invention, the com-pensating member decreases conically. Its decreased portion merges into a cylinder such that the partial beam paths which are also in the cylinder por-tion of the compensating member (as compared with the purely conical embodi-ment) are compensated by a recess provided in the base of the compensating member having an appropriate local depth. It thus results that the end of ;
the compensating member which is turned towards the radiation source is blunt and thus less~sensitive to alignment errors. The portions with strong changes of the absorption values are placed into a place perpendicular to the :
beam direction at a greater distance from the ocal point and thus into an 20 area where the beam cone has-already widened to a greater extent. ;
; A further reduction of the preciseness with which the compensating member must be aligned in the beam cone is obtained when, in a further develop-ment of the invention, the front surface of the cylindrical portion of the compensating member turned towards the target has its margins rounded and ; the outer portion of the recess is slightly distorted outwardly at the base of the compensating member in order to compensate the absorption. Thus, the alignment of the compensating member becomes less critical, including that ~ ;
range of the beam cone which corresponds to the margin of the upper frontal surface of the cylindrical portion.
Thus, ln accordance ~lth one aspect of the in~ention, there is pro~ided an-electron accèlerator comprlsing:
(a) an electron beam;
- 2 - ~ .
.. .. .
.
~88ZZl (b) a target means exposed to the electron beam for producing x-ray deceleration radiation in the shape of a cone;
(c) a massive conical compensa~ing means arranged centrally in the cone of the x-ray radiation, said compensating means having a decreasing conical shape towards the target means, and a base away from the traget means;
(d) said decreasing conical shape merging into a cylindrical portion having a frontal surface adjacent the target means; and ~ e) a recess means positioned adjacent the base of the compensa-ting means and having a given depth for compensating portions of the x-ray radiation in the cylindrical portion outwardly from the center of the~radia-tion cone, said portions being those portions of the x-ray radiation inter- ~
cepted by the cylindrical portion which are additional to those portions in- ~ -tercepted in a conical embodiment of the compensating means. :
Figure 1 is a diagram of the intensity distributions in the beam - 2a -~ ;
: ' - ~'''', ; :
~0882Zl cone both with and wlthout a compensating member;
Pigure 2 is a sc~ematic representation of a partially sectioned .:
beam dle~ining system comprising a target, a collimator, and a compensating rnember placed into the collimator;
Pigure 3 shows an enlarged illustration of the compensating memb of Figure l; and Pigure 4 is another embodiment of a compensating member in a bea~
defining system.
In the case of a properly employed conical compensating member, ::~
the intensity distribution as indicated by broken line 36 in Fi~ure 1 and which would be assumed by the beam cone leavi.ng the target at the location plane of a patlent undergoing treatment would be changed intd the continuous line 37. The compensating member absorbs the overly intense radiation in the center as compared with the margins of a given beam cone. The portion of the beam cone having the intensity distribtuion represented by the horizontal portion of curve 37 in Figure 1 can be used for radiation purposes. Even for exact positioning, misadjustments of dose compensation can occur due to minor fluctuations of the direction of the electron beam leaving the accelerator. ~-Figure 2 shows the locations of an exit windo~ 1 of a vacuum tube ;
2 for the electron beam, a t~rget 3, a col].imator 4, adjustable x-ray shielding aperture plates 5, 6, 7, and the compensating member 8 in the partially sectioned beam defining system 9.
The target 3 is arranged in the beam direction directly behind the ` ~ exit window 1 of the ~acuum tube 2. It is positioned in a boring of a carrier plate 10. An.electron absorption member 11 is positioned in this boring di-rectly behlnd the target in the beam direction. The collimator 4 is position-. ed in *he bea~ direction directly behind the carrier pla~e 10 for the target ,: 3. Tt9 conical passage opening 12 for the radiation has a diameter of a few ~m more than the ~aximum useful portion o~ the radlation cone 13. It is aligned ~ith respect to the center bea~ l4 of the beam cone 13. The x-ray shielding a~justable aperture plates 5, 6~ 7 are arranged behind the colli-.A
. -. ...
1~38Z21 mator in the beam direction in order to adapt the width of the beam cone to the respective therapeutically required field magnitude. An ionizat:ion chamber 16 for supervising the exiting beam is arranged between collimator 4 and the x-ray ad~ustable screen plates 5, 6, 7. An iron plate 15 with the compensating member attached thereupon is screwed to the side of the collimator 4 which is turned away from the target 3.
This compensating member 8 i~ shown enlarged in Figure 3. It es-sentially comprises an increasingly more pointed conical member whose upper section (which usually merges into a tip shown as a broken line) has been re-- 3a -~ '' ;' placed by a cylindrical portion 17. The mar~ins of tho frontal surfaces of the cylindrical soctions which are turned towards thc radiation sources are rounded. A ring-shaped rocess 18 extending at an acut~ angle into the compen sating member is positioned at the base of the compensating member. In Figure
.. .. .
.
~88ZZl (b) a target means exposed to the electron beam for producing x-ray deceleration radiation in the shape of a cone;
(c) a massive conical compensa~ing means arranged centrally in the cone of the x-ray radiation, said compensating means having a decreasing conical shape towards the target means, and a base away from the traget means;
(d) said decreasing conical shape merging into a cylindrical portion having a frontal surface adjacent the target means; and ~ e) a recess means positioned adjacent the base of the compensa-ting means and having a given depth for compensating portions of the x-ray radiation in the cylindrical portion outwardly from the center of the~radia-tion cone, said portions being those portions of the x-ray radiation inter- ~
cepted by the cylindrical portion which are additional to those portions in- ~ -tercepted in a conical embodiment of the compensating means. :
Figure 1 is a diagram of the intensity distributions in the beam - 2a -~ ;
: ' - ~'''', ; :
~0882Zl cone both with and wlthout a compensating member;
Pigure 2 is a sc~ematic representation of a partially sectioned .:
beam dle~ining system comprising a target, a collimator, and a compensating rnember placed into the collimator;
Pigure 3 shows an enlarged illustration of the compensating memb of Figure l; and Pigure 4 is another embodiment of a compensating member in a bea~
defining system.
In the case of a properly employed conical compensating member, ::~
the intensity distribution as indicated by broken line 36 in Fi~ure 1 and which would be assumed by the beam cone leavi.ng the target at the location plane of a patlent undergoing treatment would be changed intd the continuous line 37. The compensating member absorbs the overly intense radiation in the center as compared with the margins of a given beam cone. The portion of the beam cone having the intensity distribtuion represented by the horizontal portion of curve 37 in Figure 1 can be used for radiation purposes. Even for exact positioning, misadjustments of dose compensation can occur due to minor fluctuations of the direction of the electron beam leaving the accelerator. ~-Figure 2 shows the locations of an exit windo~ 1 of a vacuum tube ;
2 for the electron beam, a t~rget 3, a col].imator 4, adjustable x-ray shielding aperture plates 5, 6, 7, and the compensating member 8 in the partially sectioned beam defining system 9.
The target 3 is arranged in the beam direction directly behind the ` ~ exit window 1 of the ~acuum tube 2. It is positioned in a boring of a carrier plate 10. An.electron absorption member 11 is positioned in this boring di-rectly behlnd the target in the beam direction. The collimator 4 is position-. ed in *he bea~ direction directly behind the carrier pla~e 10 for the target ,: 3. Tt9 conical passage opening 12 for the radiation has a diameter of a few ~m more than the ~aximum useful portion o~ the radlation cone 13. It is aligned ~ith respect to the center bea~ l4 of the beam cone 13. The x-ray shielding a~justable aperture plates 5, 6~ 7 are arranged behind the colli-.A
. -. ...
1~38Z21 mator in the beam direction in order to adapt the width of the beam cone to the respective therapeutically required field magnitude. An ionizat:ion chamber 16 for supervising the exiting beam is arranged between collimator 4 and the x-ray ad~ustable screen plates 5, 6, 7. An iron plate 15 with the compensating member attached thereupon is screwed to the side of the collimator 4 which is turned away from the target 3.
This compensating member 8 i~ shown enlarged in Figure 3. It es-sentially comprises an increasingly more pointed conical member whose upper section (which usually merges into a tip shown as a broken line) has been re-- 3a -~ '' ;' placed by a cylindrical portion 17. The mar~ins of tho frontal surfaces of the cylindrical soctions which are turned towards thc radiation sources are rounded. A ring-shaped rocess 18 extending at an acut~ angle into the compen sating member is positioned at the base of the compensating member. In Figure
3, several selected beams 14, 19, 20 of the beam cone 13 are shown as broken lines These selected beams reveal that the ring-shaped recess 18 is providet in such a way that it compensates those partial paths which represent x-rays leaving the target 3 divergently. These partial paths are positioned in the cylindrical section 17 of the compensating member 8 and are additional to those in a pointed compensating member. It thus results that the outer margin of the ring-shaped recess must have a bulge 21 in order to compensate the rounding 22 at the upper margin of the cylindrical portion.
` During the alignment of the compensating member 8, plane 23, which - is perpendicular to the center beam, is of importance since the ring-shaped ,, recess 18 in the compensating member merges into an acute angle within this plane. This plane is spaced from the base 24 of the compensating member at a distance equal to the height of the cylindrical section 17. In the csse of the present embodiment having a cylindrical section representing one-third of the entire height of the compensating member 8, this plane 23 is further remote ~
from the target 3 by two-thirds of the height of the compensating member than ~ ;-in a conventional compensating member ending in a point. In this plane 23, the beam cone 13 is already widened to a larger extent so that the alignment becomes less critical to the same extent.
Figure 4 shows another solution for the same problem. Here, the compensating ~ember 36, which is otherwise provided in a manner known to a large extent in the prior art, is placed upside down, along with an otherwise identical embodiment of the beam defining system 25. The compensating member 36 is positioned in the passage opening of the collimator 31 with a tip 37 turned away from the target 30. Thus, the critical align~ent plane 39 in the area of the tip 37 of the compensating member 36 is spaced over the full .. . . .
. .
.
1~)882Zl height of the compensating mombor 36 away from the target 30. In the caso of this arrangement, a pointed compensating momber 36 can be usod ~ithout a ring groove milled into the base. When the compensating member is rotated 180, due to the divergence of tho radiation all sides of the componsating momber 25 must be provided more steeply at twico the angle of the beam divergence. In order to attach the compensat~ng member 36 ~ithin the collimator 31, a conical pass-age opening 38 has a cylindrical portion in the center range of the collimator.
This cylindrical portion has a~ its upper end a ring groove 40 of a larger diameter. This ring groovo is thus arrangod in a plane perpondicular to the symmetrical axis of the collimator 31 which coincidos with the center beam 28.
In this ring groovo 40 clamping jaws 42, 43 are arranged which can be adjusted via screw threads 41 (only one is shown) and which are displaced from one another by 120. A carrier plate 44 which is connectod with tho base of the compensating member 36 can be mounted between these clamping jaws 42, 43. The margin of the carrier plate 44 is conically inclined into an angle of 45 in the direction towards the tip of the compensating member. The clamping sur-faces of the clamping jaws 42, 43 are adapted to meet with this inclination.
Although various minor modifications may be suggestod by those versed in the art, it should be understood that it is intended to embody within the scope of the patent warranted hereon, all such embodiments as reasonably and properly come within the scope of this contribution to the art.
` During the alignment of the compensating member 8, plane 23, which - is perpendicular to the center beam, is of importance since the ring-shaped ,, recess 18 in the compensating member merges into an acute angle within this plane. This plane is spaced from the base 24 of the compensating member at a distance equal to the height of the cylindrical section 17. In the csse of the present embodiment having a cylindrical section representing one-third of the entire height of the compensating member 8, this plane 23 is further remote ~
from the target 3 by two-thirds of the height of the compensating member than ~ ;-in a conventional compensating member ending in a point. In this plane 23, the beam cone 13 is already widened to a larger extent so that the alignment becomes less critical to the same extent.
Figure 4 shows another solution for the same problem. Here, the compensating ~ember 36, which is otherwise provided in a manner known to a large extent in the prior art, is placed upside down, along with an otherwise identical embodiment of the beam defining system 25. The compensating member 36 is positioned in the passage opening of the collimator 31 with a tip 37 turned away from the target 30. Thus, the critical align~ent plane 39 in the area of the tip 37 of the compensating member 36 is spaced over the full .. . . .
. .
.
1~)882Zl height of the compensating mombor 36 away from the target 30. In the caso of this arrangement, a pointed compensating momber 36 can be usod ~ithout a ring groove milled into the base. When the compensating member is rotated 180, due to the divergence of tho radiation all sides of the componsating momber 25 must be provided more steeply at twico the angle of the beam divergence. In order to attach the compensat~ng member 36 ~ithin the collimator 31, a conical pass-age opening 38 has a cylindrical portion in the center range of the collimator.
This cylindrical portion has a~ its upper end a ring groove 40 of a larger diameter. This ring groovo is thus arrangod in a plane perpondicular to the symmetrical axis of the collimator 31 which coincidos with the center beam 28.
In this ring groovo 40 clamping jaws 42, 43 are arranged which can be adjusted via screw threads 41 (only one is shown) and which are displaced from one another by 120. A carrier plate 44 which is connectod with tho base of the compensating member 36 can be mounted between these clamping jaws 42, 43. The margin of the carrier plate 44 is conically inclined into an angle of 45 in the direction towards the tip of the compensating member. The clamping sur-faces of the clamping jaws 42, 43 are adapted to meet with this inclination.
Although various minor modifications may be suggestod by those versed in the art, it should be understood that it is intended to embody within the scope of the patent warranted hereon, all such embodiments as reasonably and properly come within the scope of this contribution to the art.
Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An electron accelerator comprising:
a) an electron beam;
b) a target means exposed to the electron beam for producing x-ray deceleration radiation in the shape of a cone;
c) a massive conical compensating means arranged centrally in the cone of the x-ray radiation, said compensating means having a decreasing conical shape towards the target means, and a base away from the target means;
d) said decreasing conical shape merging into a cylindrical portion having a frontal surface adjacent the target means; and e) a recess means positioned adjacent the base of the compensating means and having a given depth for compensating portions of the x-ray radiation in the cylindrical portion outwardly from the center of the radiation cone, said portions being those portions of the x-ray radiation intercepted by the cylindrical portion which are additional to those portions intercepted in a conical embodiment of the compensating means.
a) an electron beam;
b) a target means exposed to the electron beam for producing x-ray deceleration radiation in the shape of a cone;
c) a massive conical compensating means arranged centrally in the cone of the x-ray radiation, said compensating means having a decreasing conical shape towards the target means, and a base away from the target means;
d) said decreasing conical shape merging into a cylindrical portion having a frontal surface adjacent the target means; and e) a recess means positioned adjacent the base of the compensating means and having a given depth for compensating portions of the x-ray radiation in the cylindrical portion outwardly from the center of the radiation cone, said portions being those portions of the x-ray radiation intercepted by the cylindrical portion which are additional to those portions intercepted in a conical embodiment of the compensating means.
2. An electron accelerator in accordance with claim 1, characterized in that the frontal surface of the cylindrical portion of the compensating means which is turned towards the target has margins which are rounded, and an outer edge of the recess means protrudes slightly outwardly at the base of the compensating means for compensating absorption.
3. An electron accelerator in accordance with claim 1, characterized in that the cylindrical portion extends over approximately one-third of the overall compensating means height.
4. An electron accelerator in accordance with claim 1 in which the compensating means is made of stainless steel.
5. An electron accelerator in accordance with claim 1 in which the compensating means comprises several sections with differing side inclina-tions, the inclinations being steeper with increasing distance from the base.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA349,954A CA1097437A (en) | 1977-03-18 | 1980-04-16 | Electron accelerator |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US779,025 | 1977-03-18 | ||
| US05/779,025 US4109154A (en) | 1977-03-18 | 1977-03-18 | X-ray beam compensation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1088221A true CA1088221A (en) | 1980-10-21 |
Family
ID=25115086
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA286,193A Expired CA1088221A (en) | 1977-03-18 | 1977-09-07 | Electron accelerator |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4109154A (en) |
| JP (1) | JPS53117200A (en) |
| CA (1) | CA1088221A (en) |
| DE (1) | DE2727354C3 (en) |
| FR (1) | FR2384416A1 (en) |
| GB (1) | GB1601517A (en) |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4286167A (en) * | 1979-05-14 | 1981-08-25 | Varian Associates, Inc. | Multi-element X-ray equalizing filter |
| DE2926823A1 (en) * | 1979-07-03 | 1981-01-22 | Siemens Ag | ELECTRONIC ACCELERATOR |
| EP0157129A1 (en) * | 1984-02-21 | 1985-10-09 | Siemens Aktiengesellschaft | Electron accelerator |
| JPH0732943Y2 (en) * | 1989-03-07 | 1995-07-31 | 株式会社明電舎 | Pelton Turbine Discharge Garden |
| US5153900A (en) * | 1990-09-05 | 1992-10-06 | Photoelectron Corporation | Miniaturized low power x-ray source |
| US5369679A (en) * | 1990-09-05 | 1994-11-29 | Photoelectron Corporation | Low power x-ray source with implantable probe for treatment of brain tumors |
| US5452720A (en) * | 1990-09-05 | 1995-09-26 | Photoelectron Corporation | Method for treating brain tumors |
| US5442678A (en) * | 1990-09-05 | 1995-08-15 | Photoelectron Corporation | X-ray source with improved beam steering |
| US5216255A (en) * | 1992-03-31 | 1993-06-01 | Siemens Medical Laboratories | Beam profile generator for photon radiation |
| US5332908A (en) * | 1992-03-31 | 1994-07-26 | Siemens Medical Laboratories, Inc. | Method for dynamic beam profile generation |
| US6799075B1 (en) | 1995-08-24 | 2004-09-28 | Medtronic Ave, Inc. | X-ray catheter |
| US6377846B1 (en) | 1997-02-21 | 2002-04-23 | Medtronic Ave, Inc. | Device for delivering localized x-ray radiation and method of manufacture |
| EP0860181B1 (en) * | 1997-02-21 | 2004-04-28 | Medtronic Ave, Inc. | X-ray device having a dilatation structure for delivering localized radiation to an interior of a body |
| US5854822A (en) * | 1997-07-25 | 1998-12-29 | Xrt Corp. | Miniature x-ray device having cold cathode |
| US6108402A (en) * | 1998-01-16 | 2000-08-22 | Medtronic Ave, Inc. | Diamond vacuum housing for miniature x-ray device |
| US6069938A (en) * | 1998-03-06 | 2000-05-30 | Chornenky; Victor Ivan | Method and x-ray device using pulse high voltage source |
| US6195411B1 (en) | 1999-05-13 | 2001-02-27 | Photoelectron Corporation | Miniature x-ray source with flexible probe |
| US6353658B1 (en) | 1999-09-08 | 2002-03-05 | The Regents Of The University Of California | Miniature x-ray source |
| KR100382760B1 (en) * | 2000-09-25 | 2003-05-01 | 삼성전자주식회사 | Electron spectroscopic analyzer using X-ray |
| US8890100B2 (en) * | 2012-08-15 | 2014-11-18 | Varian Medical Systems, Inc. | Internally mounted collimators for stereotactic radiosurgery and stereotactic radiotherapy |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3917954A (en) * | 1973-11-09 | 1975-11-04 | Gundersen Clinic Ltd | External x-ray beam flattening filter |
| SE390697B (en) * | 1974-04-10 | 1977-01-17 | Scandiatronix Instr Ab | DEVICE FOR THE EFFECT OF ENERGY DISTRIBUTION AND SPATIAL DISTRIBUTION OF HOGENERGETIC PARTICULATE RADIATION WHEN IRRADIZING A LIMITED VOLUME |
| CA1009382A (en) * | 1974-12-18 | 1977-04-26 | Her Majesty In Right Of Canada As Represented By Atomic Energy Of Canada Limited | X-ray beam flattener |
| US3969629A (en) * | 1975-03-14 | 1976-07-13 | Varian Associates | X-ray treatment machine having means for reducing secondary electron skin dose |
-
1977
- 1977-03-18 US US05/779,025 patent/US4109154A/en not_active Expired - Lifetime
- 1977-06-16 DE DE2727354A patent/DE2727354C3/en not_active Expired
- 1977-09-07 CA CA286,193A patent/CA1088221A/en not_active Expired
- 1977-12-16 JP JP15158977A patent/JPS53117200A/en active Granted
-
1978
- 1978-03-15 FR FR7807425A patent/FR2384416A1/en active Granted
- 1978-03-17 GB GB10784/78A patent/GB1601517A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE2727354C3 (en) | 1981-02-19 |
| GB1601517A (en) | 1981-10-28 |
| FR2384416B1 (en) | 1982-10-01 |
| DE2727354A1 (en) | 1978-09-21 |
| FR2384416A1 (en) | 1978-10-13 |
| JPS53117200A (en) | 1978-10-13 |
| US4109154A (en) | 1978-08-22 |
| DE2727354B2 (en) | 1980-04-10 |
| JPS6252280B2 (en) | 1987-11-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1088221A (en) | Electron accelerator | |
| US5396889A (en) | Stereotactic radiosurgery method and apparatus | |
| US4359642A (en) | Collimator assembly for an electron accelerator | |
| US4157475A (en) | Electron accelerator comprising a target exposed to the electron beam | |
| JPS63501735A (en) | Improved X-ray attenuation method and device | |
| US4343997A (en) | Collimator assembly for an electron accelerator | |
| CN108969907A (en) | Obtain the particle beam therapy head device of small beam spot | |
| US5892238A (en) | Radiation therapy shielding assembly | |
| US6687332B2 (en) | Method and apparatus for patient-in-place measurement and real-time control of beam-spot position and shape in a scanning electron beam computed tomographic system | |
| CN1937100A (en) | Beam-guide-box structure integrated with ray source and front, rear collimator | |
| CA1097437A (en) | Electron accelerator | |
| CN111068189A (en) | Medical accelerator, dose monitoring system and dose monitoring method thereof | |
| CN111013026A (en) | Medical accelerator and dosage monitoring method based on leaky dosage measurement | |
| US8742326B2 (en) | Determination of beam parameters for asymmetrical photon beams | |
| JP2003114203A (en) | Ct apparatus | |
| US3882314A (en) | Device for X-ray treatment | |
| Ampollini et al. | Recombination effects in the ionization chambers dose delivery monitor of the TOP-IMPLART proton beam | |
| JPH1187089A (en) | Radiation generator | |
| KR101707219B1 (en) | X-Ray Tube Having Anode Rod for Avoiding Interference and Apparatus for Detecting with the Same | |
| KR101412611B1 (en) | Apparatus and method for enhance spatial resoution in ion chamber array | |
| JP2003139724A (en) | Ct unit | |
| Kharrati et al. | Design of a non-docking intraoperative electron beam applicator system | |
| CN107789745A (en) | A kind of robot radiation therapy system | |
| US10556129B2 (en) | Systems and methods for treating a skin condition using radiation | |
| US20100158196A1 (en) | Radiation beam blocker with non-cylindrical through-hole causing reduced geometric unsharpness in radiographic image, and method for the preparation thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |