CA1149003A - Electron gun having a low capacitance cathode and grid assembly - Google Patents
Electron gun having a low capacitance cathode and grid assemblyInfo
- Publication number
- CA1149003A CA1149003A CA000344773A CA344773A CA1149003A CA 1149003 A CA1149003 A CA 1149003A CA 000344773 A CA000344773 A CA 000344773A CA 344773 A CA344773 A CA 344773A CA 1149003 A CA1149003 A CA 1149003A
- Authority
- CA
- Canada
- Prior art keywords
- electrode
- grid
- support member
- cathode
- bonded
- 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
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
- H01J29/46—Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
- H01J29/48—Electron guns
- H01J29/488—Schematic arrangements of the electrodes for beam forming; Place and form of the elecrodes
Landscapes
- Microwave Tubes (AREA)
- Electrodes For Cathode-Ray Tubes (AREA)
Abstract
Abstract The present invention relates to an electrode assembly. The assembly is comprised of an annular insulating support member having a front face, a rear surface, and a portion defining a frusto-conical major interior surface extending between a central circular front opening adjacent the front face and a substantially smaller central circular rear opening adjacent the rear face. A first disk-shaped grid electrode is provided of a size not substantially exceeding that of the smaller opening and is disposed overlying the smaller opening and bonded at its periphery to the support member's rear surface. A second, non-planar grid electrode is bonded to the support member's front surface, the second electrode including a recessed portion extending into the front opening to position a central region of thes second electrode in closely spaced relation to the first grid electrode. The recessed portion has a frusto-conical surface disposed in axially aligned closely spaced relation to the frusto-conical interior surface of the support member. A cathode electrode is provided having an activated, electron emissive surface. Finally, a unit is provided which includes an insulating member bonded to the rear surface of the annular support member for mounting the cathode electrode with its electro-emissive surface closely adjacent the first grid electrode. The first and second grid electrodes each include a central aperture.
The apertures of the electrodes and the electron emissive surface of the cathode are arranged in mutual alignment.
The apertures of the electrodes and the electron emissive surface of the cathode are arranged in mutual alignment.
Description
ELECTRON GUN HAVING A LOW
CAPACITANCE CATHODE AND GRID ASSEMBLY
Background of the Invention In high frequency electron discharge devices such as cathode ray tubes, the capacitance between the control grid and the accelerating grid of an electron gun must present a small area to the other electrodes in the electron - 5 gun in order to reduce the input capacitance to enable the high frequency signal to be impressed on the control grid for high frequency operation.
. .
U. S. Patent No. 2,458,962 discloses a grid assembly for cathode ray tubes which comprises first and second grid members in the form of a frustum of a cone. The first grid member is closely positioned next to the cathode and the second grid member has an inner section disposed within the first grid member but spaced therefrom. This arrangement presents a large area thereby increasin~ the capacitance and is not suitable for high frequency cathode ray tubes.
The grid assembly in U. S. Patent No. 2,540,621 is of similar construction to that of U. S. P~tent No. 2,458,g62 except that the first grid member does not have a frustrum of a cone configuration; however, the metal -~ areas of the first and second grid members opposite each other present a large `' 20 area such that increased capacitance results thereby rendering this grid assembly unsuitable for high frequency operation.
The grid assembly in U. S. Patent No. 2,443,916 includes a small first grid member which is welded to an eyelet that secures the first grid member to a ceramic mountirig member onto which the second grid member is also mounted and spaced from the first grid member. This arrangement provides a large surface area that results in a large input capacitance which is a serious disadvantage to high frequency operation.
~' Summary of the Invention The present invention relates to electron discharge devices and more particularly to an electron gun structure having an improved low capacitance grid assembly for high frequency cathode ray tubes.
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CAPACITANCE CATHODE AND GRID ASSEMBLY
Background of the Invention In high frequency electron discharge devices such as cathode ray tubes, the capacitance between the control grid and the accelerating grid of an electron gun must present a small area to the other electrodes in the electron - 5 gun in order to reduce the input capacitance to enable the high frequency signal to be impressed on the control grid for high frequency operation.
. .
U. S. Patent No. 2,458,962 discloses a grid assembly for cathode ray tubes which comprises first and second grid members in the form of a frustum of a cone. The first grid member is closely positioned next to the cathode and the second grid member has an inner section disposed within the first grid member but spaced therefrom. This arrangement presents a large area thereby increasin~ the capacitance and is not suitable for high frequency cathode ray tubes.
The grid assembly in U. S. Patent No. 2,540,621 is of similar construction to that of U. S. P~tent No. 2,458,g62 except that the first grid member does not have a frustrum of a cone configuration; however, the metal -~ areas of the first and second grid members opposite each other present a large `' 20 area such that increased capacitance results thereby rendering this grid assembly unsuitable for high frequency operation.
The grid assembly in U. S. Patent No. 2,443,916 includes a small first grid member which is welded to an eyelet that secures the first grid member to a ceramic mountirig member onto which the second grid member is also mounted and spaced from the first grid member. This arrangement provides a large surface area that results in a large input capacitance which is a serious disadvantage to high frequency operation.
~' Summary of the Invention The present invention relates to electron discharge devices and more particularly to an electron gun structure having an improved low capacitance grid assembly for high frequency cathode ray tubes.
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In accordance with an aspect of the invention there is provided an electrode a.ssembly ~or an electron : diseharge device, comprising an annular insulating support member having a front face, a eear ~ace, and means deEining ` 5 a frusto-conical major interior surface extending between a central circular front opening adjacent said front face and a substantiaLly smaller central circular rear opening adjacent said rear face, a ~irst, disk-shaped grid : electrode, of a size not substantially exceeding that of ~ 10 said smaller opening, disposed overlying the smaller `- opening and bonded at its periphery to the support : member's rear face, a second, nonplanar grid eleetrode ~: bonded to the support member's front face, said seeond ~` electrode including a recessed portion extending into said `~:
~`. 15 front opening to position a central region of the seeond ` electrode in closely spaced relation to said first grid ~ eleetrode, said reeessed portion having a frusto-eonieal `~ surfaee disposed in axially-aligned, elosely-spaeed relation to said frusto-eonieal interior surfaee of the ~ 20 support member, a eathode eleetrode having an aetivated, ; eleetron-emissive surfaee, and means, ineluding an ~: insulating member bonded to the rear surfaee of said annular support member, mounting said eathode eleetrode '.~` with its electron-emissive surface closely adjacent said first grid electrede, said first and second grid eleetrodes . eaeh including a central aperture, the apertures of said electrodes and the electron-emissive surface of said cathode being arranged in mutual alignment.
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In accordance with an aspect of the invention there is provided an electrode a.ssembly ~or an electron : diseharge device, comprising an annular insulating support member having a front face, a eear ~ace, and means deEining ` 5 a frusto-conical major interior surface extending between a central circular front opening adjacent said front face and a substantiaLly smaller central circular rear opening adjacent said rear face, a ~irst, disk-shaped grid : electrode, of a size not substantially exceeding that of ~ 10 said smaller opening, disposed overlying the smaller `- opening and bonded at its periphery to the support : member's rear face, a second, nonplanar grid eleetrode ~: bonded to the support member's front face, said seeond ~` electrode including a recessed portion extending into said `~:
~`. 15 front opening to position a central region of the seeond ` electrode in closely spaced relation to said first grid ~ eleetrode, said reeessed portion having a frusto-eonieal `~ surfaee disposed in axially-aligned, elosely-spaeed relation to said frusto-eonieal interior surfaee of the ~ 20 support member, a eathode eleetrode having an aetivated, ; eleetron-emissive surfaee, and means, ineluding an ~: insulating member bonded to the rear surfaee of said annular support member, mounting said eathode eleetrode '.~` with its electron-emissive surface closely adjacent said first grid electrede, said first and second grid eleetrodes . eaeh including a central aperture, the apertures of said electrodes and the electron-emissive surface of said cathode being arranged in mutual alignment.
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The present invention is realized by securing a srnall diameter control grid to an inner planar surface of an annular ceramic member and an outer planar section of a focussing grid to an outer planar surface of the ceramic member. Another outer surface in the form of a frustum of a cone is provided as part of the ceramic member and the accelerating grid has an inner planar sectiondisposed adjacent to the control grid with the outer and inner planar sections of the accelerating grid being connected by a frustum of a cone section extending along the frustum of cone surface of the ceramic member. The area presented by this grid assembly results in a small input capacitance to enable high frequency signals to be impressed onto the control grid for high frequency operation. The spacing and alignment of the grids relative to each other and to the cathode is very accurate and the apertures in the grids are formed therein after the grids have been secured to the ceramic member so that their alignment 3, is very accurate. The cathode and grid assembly is mounted via the accelerating grid being secured to a mounting wafer.
An object of the present invention is to provide a low capacitance grid assembly as part of an electron gun for a cathode ray tube.
:- 20 Another object of the present invention is the provision of a low capacitance grid assembly which presents a small area to reduce the input capacitance.
A further object of the present invention is to provide a low capacitance grid assembly wherein the grid members are accurately positioned relative to each other.
, An additional object of the present invention is the provision of a cathode and grid assembly wherein the grid members are accurately spaced and 30 aligned relative to each other and the cathode is accurately positioned and aligned relative to the grid members.
.- A still further object of the present invention is to provide a low capacitance cathode and grid assembly which is mounted in position in a cathode 35 ray tube as part of the electron gun via the accelerating grid member.
Still an additional object of the present invention is the provision of forming the apertures in the grids of a low capacitance grid assembly after the grids have been secured onto a ceramic member.
; -Brief Description of the Drawin~
:- Other objects and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment thereof and from the attached drawing of which:
Fig. I is a perspective view of the cathode and grid assembly of the present invention; and Fig. 2 is a cross-sectional view taken along the line 2-2 of Fig. 1.
' 10 Detailed Description of the Invention ~ As shown in Figs. I and 2, a cathode and grid assembly 10 includes ; i~ an annular ceramic member 12 having its upper surface secured to an inner planar surface 16 of another ceramic member 14 by a conventional brazing ~ practice. An opening 18 is located in the center of ceramic member 14 and it,j.7` has a control grid member 20 slightly larger in diameter than opening 18 tightly secured to inner surface 16. Grid member 20 is preferrably brazed to inner ,':'!. surface 16 with braze along the entire periphery of grid member 20 or at spaced ; :' 20 locations therealong. Grid member 20 is stainless steel that has a thickness of 0.005 inches and an aperture 22 therethrough having a diameter of 0.022 inches.
Recesses 24 are located in the upper surface of ceramic member 12 that is brazed to surface 16 to enable grid wire 26 to extend to the outside of ` - 25 assembly 10 from its connection with control grid member 20. Y~ire 26 is a thin wire and has a diameter of 0.008 inches thereby providing a high inductance and low capacitance.
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Ceramic member 14 has an outer planar surface 28 and an outer 'r. ~ 30 surface 30 in the form of a frustum of a cone. An accelerating grid member 32 has an outer p~anar section 34, an inner planar section 36 and a frustum of a cone section 38 connecting sections 34 and 36 together. Section 34 is brazed to planar surface 28 in the same manner that grid member 20 is secured to inner surface 16 to secure grid member 32 in position on ceramic member 14. Section 38 conforms substantially to the configuration of a frustum of a cone surface 30 and section 38 precisely positions and aligns section 36 relative to grid member 20 so that the grid members 20 and section 36 of grid member 32 are parallel and 0.02 ',' . ~
`` L~.~,9~3~3 _ 4 _ inches apart. Section 36 has an aperture 40 therethrough having a diameter of - 0.022 inches and being accurately aligned with aperture 22. Section 36 has a diameter smaller than that of grid member 20.
,~
In order to make certain that apertures 22 and 40 are accurately - aligned, they are formed in grid members 20 and 32 after these grid members have been brazed to ceramic member 14. Apertures 22 and 40 are formed in the ; grid members by the conventional practice of electron discharge machining. In ; this way, apertures 22 and 40 are assured of being accurately aligned.
` A cathode support 42 has an inturned flange 44 brazed to the bottom surface of ceramic member 12. A ceramic disc 46 has a hole 48 in which is secured a cathode tube 50 on the end of which is secured a cathode cap 52.
Tube 50 is tightly secured in ceramic disc 46 via the formation of beadings 54 in 15 tube 50. Beadings 54 are tightly pressed against the surfaces of ceramic disc 46 to tightly lock tube 50 thereto.
.;, -; Ceramic disc 46 is positioned against flange 44 and it is secured thereagainst by flange 56 of retainer member 5% that is secured to support 42 via -` 20 a press fit or welding. In this way, cathode cap 52 is accurately positioned and aligned relative to grid member 20 and aperture 22. The spacing between grid ~ member 20 and cathode cap 52 is 0.0025 inches. The cathode cap 52 has a small : ~ diameter and tube 50 is sufficiently long to reduce capacitance. A cathode spacer 60 in the form of a metal ring of proper thickness can be placed between 25 ceramic disc 46 and flange 44 to compensate for spacing problems due to brazing ~- thickness and tolerances of flange 44, ceramic disc 46 and beadings 54 to make certain that cathode cap 52 is accurately positioned and aligned relative to grid - member 20.
: , Another ceramic disc 62 has a flange 64 that abuts against the bottom of support 42 and it is secured thereagainst by tabs 66 extending outwardly from support 42 and bent against disc 62. A heater filament 68 extends along tube 50 and has its ends connected respectively to leads 70 and 72- which are secured to ceramic disc 62 via rivets 74 that are located in holes 76.
. ~
A wafer member 78 is secured onto section 34 of grid member 32 and it has tabs 80 that are secured into glass rods for mounting the cathode andgrid assembly 10 thereon as part of the electron gun.
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~, The small diameter o~ grid member 20, the small diameter of section 36 o~ grid member 32, the small diameter cathode and small diameter of grid lead 26 al~
combine to substantially reduce capacitance so that input signals impressed onto control qrid member 20 via lead 26 will enable electron beam operation at a very high frequency without excessive loading to the grid.
Accelerating grid member 32 is connected to 200-400 volts. The accurate spacing and alignment of grid members 20 and 32 relative to each other and to the cathode enables high resolution to be realized. If desired, another high inductance grid lead 26a of the same size as lead 26 can be connected to grid member 20, and, , together with lead 26, this arrangement can form a transmission line systen for even higher frequency ~,. response.
It will be obvious to those having ordinary skill ;~l in the art that many changes may be made in the details of ` the above-described preferred embodiment of the present invention without departing from the spirit of the invention. For example, ceramic members 12 and 14 can be ~; one piece. Therefore, the scope of the present invention ;~ is to be determined by the scope of the claims.
' .
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- 2a -. .
The present invention is realized by securing a srnall diameter control grid to an inner planar surface of an annular ceramic member and an outer planar section of a focussing grid to an outer planar surface of the ceramic member. Another outer surface in the form of a frustum of a cone is provided as part of the ceramic member and the accelerating grid has an inner planar sectiondisposed adjacent to the control grid with the outer and inner planar sections of the accelerating grid being connected by a frustum of a cone section extending along the frustum of cone surface of the ceramic member. The area presented by this grid assembly results in a small input capacitance to enable high frequency signals to be impressed onto the control grid for high frequency operation. The spacing and alignment of the grids relative to each other and to the cathode is very accurate and the apertures in the grids are formed therein after the grids have been secured to the ceramic member so that their alignment 3, is very accurate. The cathode and grid assembly is mounted via the accelerating grid being secured to a mounting wafer.
An object of the present invention is to provide a low capacitance grid assembly as part of an electron gun for a cathode ray tube.
:- 20 Another object of the present invention is the provision of a low capacitance grid assembly which presents a small area to reduce the input capacitance.
A further object of the present invention is to provide a low capacitance grid assembly wherein the grid members are accurately positioned relative to each other.
, An additional object of the present invention is the provision of a cathode and grid assembly wherein the grid members are accurately spaced and 30 aligned relative to each other and the cathode is accurately positioned and aligned relative to the grid members.
.- A still further object of the present invention is to provide a low capacitance cathode and grid assembly which is mounted in position in a cathode 35 ray tube as part of the electron gun via the accelerating grid member.
Still an additional object of the present invention is the provision of forming the apertures in the grids of a low capacitance grid assembly after the grids have been secured onto a ceramic member.
; -Brief Description of the Drawin~
:- Other objects and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment thereof and from the attached drawing of which:
Fig. I is a perspective view of the cathode and grid assembly of the present invention; and Fig. 2 is a cross-sectional view taken along the line 2-2 of Fig. 1.
' 10 Detailed Description of the Invention ~ As shown in Figs. I and 2, a cathode and grid assembly 10 includes ; i~ an annular ceramic member 12 having its upper surface secured to an inner planar surface 16 of another ceramic member 14 by a conventional brazing ~ practice. An opening 18 is located in the center of ceramic member 14 and it,j.7` has a control grid member 20 slightly larger in diameter than opening 18 tightly secured to inner surface 16. Grid member 20 is preferrably brazed to inner ,':'!. surface 16 with braze along the entire periphery of grid member 20 or at spaced ; :' 20 locations therealong. Grid member 20 is stainless steel that has a thickness of 0.005 inches and an aperture 22 therethrough having a diameter of 0.022 inches.
Recesses 24 are located in the upper surface of ceramic member 12 that is brazed to surface 16 to enable grid wire 26 to extend to the outside of ` - 25 assembly 10 from its connection with control grid member 20. Y~ire 26 is a thin wire and has a diameter of 0.008 inches thereby providing a high inductance and low capacitance.
~j, .
Ceramic member 14 has an outer planar surface 28 and an outer 'r. ~ 30 surface 30 in the form of a frustum of a cone. An accelerating grid member 32 has an outer p~anar section 34, an inner planar section 36 and a frustum of a cone section 38 connecting sections 34 and 36 together. Section 34 is brazed to planar surface 28 in the same manner that grid member 20 is secured to inner surface 16 to secure grid member 32 in position on ceramic member 14. Section 38 conforms substantially to the configuration of a frustum of a cone surface 30 and section 38 precisely positions and aligns section 36 relative to grid member 20 so that the grid members 20 and section 36 of grid member 32 are parallel and 0.02 ',' . ~
`` L~.~,9~3~3 _ 4 _ inches apart. Section 36 has an aperture 40 therethrough having a diameter of - 0.022 inches and being accurately aligned with aperture 22. Section 36 has a diameter smaller than that of grid member 20.
,~
In order to make certain that apertures 22 and 40 are accurately - aligned, they are formed in grid members 20 and 32 after these grid members have been brazed to ceramic member 14. Apertures 22 and 40 are formed in the ; grid members by the conventional practice of electron discharge machining. In ; this way, apertures 22 and 40 are assured of being accurately aligned.
` A cathode support 42 has an inturned flange 44 brazed to the bottom surface of ceramic member 12. A ceramic disc 46 has a hole 48 in which is secured a cathode tube 50 on the end of which is secured a cathode cap 52.
Tube 50 is tightly secured in ceramic disc 46 via the formation of beadings 54 in 15 tube 50. Beadings 54 are tightly pressed against the surfaces of ceramic disc 46 to tightly lock tube 50 thereto.
.;, -; Ceramic disc 46 is positioned against flange 44 and it is secured thereagainst by flange 56 of retainer member 5% that is secured to support 42 via -` 20 a press fit or welding. In this way, cathode cap 52 is accurately positioned and aligned relative to grid member 20 and aperture 22. The spacing between grid ~ member 20 and cathode cap 52 is 0.0025 inches. The cathode cap 52 has a small : ~ diameter and tube 50 is sufficiently long to reduce capacitance. A cathode spacer 60 in the form of a metal ring of proper thickness can be placed between 25 ceramic disc 46 and flange 44 to compensate for spacing problems due to brazing ~- thickness and tolerances of flange 44, ceramic disc 46 and beadings 54 to make certain that cathode cap 52 is accurately positioned and aligned relative to grid - member 20.
: , Another ceramic disc 62 has a flange 64 that abuts against the bottom of support 42 and it is secured thereagainst by tabs 66 extending outwardly from support 42 and bent against disc 62. A heater filament 68 extends along tube 50 and has its ends connected respectively to leads 70 and 72- which are secured to ceramic disc 62 via rivets 74 that are located in holes 76.
. ~
A wafer member 78 is secured onto section 34 of grid member 32 and it has tabs 80 that are secured into glass rods for mounting the cathode andgrid assembly 10 thereon as part of the electron gun.
6~0~
~, The small diameter o~ grid member 20, the small diameter of section 36 o~ grid member 32, the small diameter cathode and small diameter of grid lead 26 al~
combine to substantially reduce capacitance so that input signals impressed onto control qrid member 20 via lead 26 will enable electron beam operation at a very high frequency without excessive loading to the grid.
Accelerating grid member 32 is connected to 200-400 volts. The accurate spacing and alignment of grid members 20 and 32 relative to each other and to the cathode enables high resolution to be realized. If desired, another high inductance grid lead 26a of the same size as lead 26 can be connected to grid member 20, and, , together with lead 26, this arrangement can form a transmission line systen for even higher frequency ~,. response.
It will be obvious to those having ordinary skill ;~l in the art that many changes may be made in the details of ` the above-described preferred embodiment of the present invention without departing from the spirit of the invention. For example, ceramic members 12 and 14 can be ~; one piece. Therefore, the scope of the present invention ;~ is to be determined by the scope of the claims.
' .
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Claims (5)
1. An electrode assembly for an electron discharge device, comprising an annular insulating support member having a front face, a rear face, and means defining a frusto-conical major interior surface extending between a central circular front opening adjacent said front face and a substantially smaller central circular rear opening adjacent said rear face, a first, disk-shaped grid electrode, of a size not substantially exceeding that of said smaller opening, dis-posed overlying the smaller opening and bonded at its periphery to the support member's rear face, a second, nonplanar grid electrode bonded to the sup-port member's front face, said second electrode including a recessed portion extending into said front opening to posi-tion a central region of the second electrode in closely-spaced relation to said first grid electrode, said recessed portion having a frusto-conical surface disposed in axially-aligned, closely-spaced relation to said frusto-conical interior surface of the support member, a cathode electrode having an activated, electron-emissive surface, and means, including an insulating member bonded to the rear surface of said annular support member, mounting said cathode electrode with its electro-emissive surface closely adjacent said first grid electrode, said first and second grid electrodes each including a central aperture, the apertures of said electrodes and the electron-emissive surface of said cathode being arranged in mutual alignment.
2. The electrode assembly of claim 1, wherein the central apertures of the first and second electrodes are substantially equal in diameter.
3. The electrode assembly of claim 1, wherein the insulating member bonded to the rear surface of said annular support member is a tubular ceramic member having one end bonded to said surface adjacent the outer perimeter of said annular member.
4. The electrode assembly of claim 3, wherein said tubular member includes means defining a passage through the wall thereof at a location adjacent said one end, and wherein a high inductance electrical lead extends through said hole and connects to said first grid electrode.
5. The electrode assembly of claim 1, wherein the second electrode's recessed central region is smaller in size than the opening in the annular member's rear face.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US2847379A | 1979-04-09 | 1979-04-09 | |
| US28,473 | 1979-04-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1149003A true CA1149003A (en) | 1983-06-28 |
Family
ID=21843648
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000344773A Expired CA1149003A (en) | 1979-04-09 | 1980-01-31 | Electron gun having a low capacitance cathode and grid assembly |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5919620B2 (en) |
| CA (1) | CA1149003A (en) |
| DE (1) | DE3010807A1 (en) |
| FR (1) | FR2454177B1 (en) |
| GB (1) | GB2046511B (en) |
| NL (1) | NL8000814A (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL8005230A (en) * | 1980-09-19 | 1982-04-16 | Philips Nv | CATHED BEAM TUBE. |
| JPS58188037A (en) * | 1982-04-28 | 1983-11-02 | Sony Corp | Electron gun |
| DE19534124A1 (en) * | 1995-09-14 | 1997-03-20 | Licentia Gmbh | cathode ray tube |
| DE19534123A1 (en) * | 1995-09-14 | 1997-03-20 | Licentia Gmbh | Cathode ray tube assembly |
| JPH09199019A (en) * | 1996-01-19 | 1997-07-31 | Sony Corp | Assembly method of electron gun for cathode-ray tube and cathode structure |
| JP3473248B2 (en) * | 1996-03-08 | 2003-12-02 | 松下電器産業株式会社 | Cathode ray tube |
| DE19630200A1 (en) * | 1996-07-26 | 1998-01-29 | Aeg Elektronische Roehren Gmbh | cathode ray tube |
| DE10118652A1 (en) * | 2001-04-14 | 2002-10-17 | Thales Electron Devices Gmbh | Cathode ray tube has electrode system with first control grid in form of flat metal plate held in bearer structure in self-supporting manner separately from second control grid |
| DE10161209C1 (en) * | 2001-12-13 | 2003-02-27 | Samtel Electron Devices Gmbh | Cathode ray tube has control grids positioned in front of cathode with central control grid provided by partial electrode grids |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2227051A (en) * | 1933-09-23 | 1940-12-31 | Wienecke Bruno | Braun tube |
| BE440730A (en) * | 1940-03-29 | |||
| US2443916A (en) * | 1947-06-27 | 1948-06-22 | Rca Corp | Cathode-grid assembly for cathode-ray tubes |
| US2505261A (en) * | 1947-08-29 | 1950-04-25 | Honeywell Regulator Co | Beam type of electron discharge tubes |
| US2540621A (en) * | 1948-02-19 | 1951-02-06 | Rca Corp | Electron gun structure |
| GB1097588A (en) * | 1964-01-06 | 1968-01-03 | Emi Ltd | Improvements in or relating to electron gun structures |
| US3458962A (en) * | 1966-12-02 | 1969-08-05 | Monsanto Co | Vinyl siding bracket |
| CA1065386A (en) * | 1975-10-31 | 1979-10-30 | Nippon Electric Co. | Electron tube provided with a cylindrical ceramic envelope part |
-
1980
- 1980-01-25 GB GB8002559A patent/GB2046511B/en not_active Expired
- 1980-01-31 CA CA000344773A patent/CA1149003A/en not_active Expired
- 1980-02-08 NL NL8000814A patent/NL8000814A/en not_active Application Discontinuation
- 1980-03-20 DE DE19803010807 patent/DE3010807A1/en active Granted
- 1980-04-03 JP JP4404280A patent/JPS5919620B2/en not_active Expired
- 1980-04-09 FR FR8008247A patent/FR2454177B1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB2046511B (en) | 1983-04-20 |
| DE3010807C2 (en) | 1990-05-23 |
| FR2454177A1 (en) | 1980-11-07 |
| JPS55139745A (en) | 1980-10-31 |
| NL8000814A (en) | 1980-10-13 |
| GB2046511A (en) | 1980-11-12 |
| DE3010807A1 (en) | 1980-10-16 |
| JPS5919620B2 (en) | 1984-05-08 |
| FR2454177B1 (en) | 1985-07-26 |
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