Shadow mask cathode ray tube shield

Claim 2

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, a mask electrode including a multi-apertured masking portion and a peripheral reinforcing and supporting portion, said mask electrode being disposed within said panel and surrounded by said side wall with a continuous spacing gap between said side wall and said peripheral portion, means for projecting electrons toward said electrode, and an electron shield extending between said electrode and said side wall and completely blocking the passage of electrons through said spacing gap; said shield comprising a strip of metal foil and extending entirely around said gap and having a pair of flanges extending along the length thereof, one of said flanges extending along and secured to said electrode, the other flange extending along and conforming closely to said side wall, said peripheral portion of said mask electrode comprising a plurality of mounting members located within said spacing gap and supporting said electrode in said panel, said mounting members being completely shielded from said electrons by said electron shield.

Claim 3

The cathode ray tube of claim 1, wherein said faceplate, side wall and mask electrode have similar generally rectangular shapes with rounded corners, and said electron shield is made up of four pieces each lying along one side of the rectangle, with the ends of adjacent pieces overlapped at the corners of the rectangle.

Claim 4

The cathode ray tube of claim 1, wherein said peripheral portion of said electrode comprises a frame of L-shaped cross-section across which said masking member is mounted, and said one shield flange is disposed against and secured to one of the flanges of said frame by tabs extending from said one shield flange and crimped over the rim of said one frame flange.

Claim 5

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, a multi-apertured mask electrode mounted within said panel and surrounded by said side wall with a spacing gap between said side wall and said mask electrode, said faceplate, side wall and mask electrode having similar generally rectangular shapes with rounded corners whereby an electron beam scanning a rectangular raster on said mask electrode tends to overscan said mask electrode particularly at said corners, and an electron shield of metal foil extending between said mask electrode and said side wall and completely blocking the passage of electrons through said gap, said shield comprising a pair of flanges extending along the length thereof, one flange being secured to said mask electrode and the other flange being pressed against said side wall to conform thereto, said shield comprising a substantial portion of U-shaped cross-section at each of said corners disposed within said spacing gap with the sides of the U resiliently engaging said side wall and the outer edge of said mask electrode.

Claim 6

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, a multi-apertured mask electrode mounted within said panel and surrounded by said side wall with a spacing gap between said side wall and said mask electrode, said faceplate, side wall and mask electrode having similar generally rectangular shapes with rounded corners whereby an electron beam scanning a rectangular raster on said mask electrode tends to overscan said mask electrode particularly at said corners, and an electron shield of metal foil extending between said mask electrode and said side wall and completely blocking the passage of electrons through said gap, said shield comprising a pair of flanges extending along the length thereof, one flange being secured to said mask electrode and the other flange being pressed against said side wall to conform thereto, said shield comprising a substantial portion of U-shaped cross-section at each of said corners disposed within said spacing gap with the sides of the U resiliently engaging said side wall and the outer edge of said mask electrode.

Claim 7

The cathode ray tube of claim 4, wherein said mask electrode includes a peripheral frame to which said one flange is secured.

Claim 8

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, a multi-apertured mask mounted within said panel and having a peripheral frame of L-shaped cross-section surrounded by said side wall with a spacing gap between said side wall and said frame, said faceplate, side wall, mask and frame having similar generally rectangular shapes with rounded corners whereby an electron beam scanning a rectangular raster on said mask tends to overscan said mask particularly at said corners, and an electron shield of metal foil disposed between said frame and said side wall and spanning said gap, said shield comprising a pair of flanges extending along the length thereof, one shield flange being secured to one of the L flanges of said frame and the other shield flange being pressed against said side wall to conform thereto, said shield comprising a substantial portion of U-shaped cross-section at each of said corners disposed within said spacing gap with the sides of the U resiliently engaging said side wall and the other flange of said frame.

Claim 9

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, a multi-apertured mask mounted within said panel and having a peripheral frame of L-shaped cross-section surrounded by said side wall with a spacing gap between said side wall and said frame, said faceplate, side wall, mask and frame having similar generally rectangular shapes with rounded corners whereby an electron beam scanning a rectangular raster on said mask tends to overscan said mask particularly at said corners, and an electron shield of metal foil disposed between said frame and said side wall and spanning said gap, said shield comprising a pair of flanges extending along the length thereof, one shield flange being secured to one of the L flanges of said frame and the other shield flange being pressed against said side wall to conform thereto, said shield comprising a substantial portion of U-shaped cross-section at each of said corners disposed within said spacing gap with the sides of the U resiliently engaging said side wall and the other flange of said frame.

Claim 10

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, an electrode disposed in said panel and comprising a frame of L-shaped cross-section and a multi-apertured sheet metal masking member mounted thereacross, and an electron shield comprising a metal foil strip having a pair of flanges extending along the length thereof, one of the flanges of the strip having tabs extending therefrom, said foil strip being disposed with the tabbed flange thereof against one of the L flanges of the frame with said tabs being crimped over the rim of said one frame flange and with the other flange of the strip being pressed against said side wall.

Claim 11

A cathode ray tube including an envelope panel comprising a faceplate and a peripheral side wall, an electrode disposed in said panel and comprising a frame of L-shaped cross-section and a multi-apertured sheet metal masking member mounted thereacross, and an electron shield comprising a metal foil strip having a pair of flanges extending along the length thereof, one of the flanges of the strip having tabs extending therefrom, said foil strip being disposed with the tabbed flange thereof against one of the L flanges of the frame with said tabs being crimped over the rim of said one frame flange and with the other flange of the strip being pressed against said side wall.

Claim 12

The cathode ray tube of claim 7 wherein: said frame is surrounded by said side wall with a spacing gap between said side wall and said frame; said faceplate, side wall, masking member and frame have similar generally rectangular shapes with rounded corners whereby an electron beam scanning a rectangular raster on said masking member tends to overscan said masking member particularly at said corners; said electron shield spans said gap and comprises a substantial portion of U-shaped cross-section at each of said corners extending a substantial distance into said gap and resiliently wedged between said side wall and said frame.

Claim 13

A cathode ray tube having a central longitudinal axis and comprising: a. an envelope including a panel member and a funnel member, said panel member comprising a faceplate disposed centrally perpendicularly to said axis and a side wall extending substantially axially from the periphery of said faceplate, b. a mosaic screen of phosphor dots on said faceplate, c. electron gun means disposed within the neck of said funnel and adapted to project electrons toward said screen, d. a shadow mask electrode mounted within said panel surrounded by said side wall, said electrode comprising a frame and a multi-apertured sheet metal masking member mounted thereacross, said frame having an L-shaped cross-section with a transverse flange of the frame L disposed substantially perpendicularly to said axis and an axial flange of the frame L disposed substantially parallel to said axis and spaced by a gap from said side wall, and e. an electron shield comprising a strip of aluminum foil having a black ceramic coating thereon and having first and second flanges extending along the length of the strip at the two longitudinal edges thereof, said first flange including integral tabs extending laterally therefrom, said shield being disposed with said first flange against said transverse frame flange and with said tabs extending inwardly toward said axis and crimped around the rim of said transverse frame flange, said second flange of said shield being disposed with a substantial portion lying flush against said sidewall, said foil shield further including along selected portions thereof a longitudinally extending U-shaped intermediate section between said flanges and extending into said gap to urge said second flange against said sidewall in a cantilever-like action.

Claim 14

A cathode ray tube having a central longitudinal axis and comprising: a. an envelope including a panel member and a funnel member, said panel member comprising a faceplate disposed centrally perpendicularly to said axis and a side wall extending substantially axially from the periphery of said faceplate, b. a mosaic screen of phosphor dots on said faceplate, c. electron gun means disposed within the neck of said funnel and adapted to project electrons toward said screen, d. a shadow mask electrode mounted within said panel surrounded by said side wall, said electrode comprising a frame and a multi-apertured sheet metal masking member mounted thereacross, said frame having an L-shaped cross-section with a transverse flange of the frame L disposed substantially perpendicularly to said axis and an axial flange of the frame L disposed substantially parallel to said axis and spaced by a gap from said side wall, and e. an electron shield comprising a strip of aluminum foil having a black ceramic coating thereon and having first and second flanges extending along the length of the strip at the two longitudinal edges thereof, said first flange including integral tabs extending laterally therefrom, said shield being disposed with said first flange against said transverse frame flange and with said tabs extending inwardly toward said axis and crimped around the rim of said transverse frame flange, said second flange of said shield being disposed with a substantial portion lying flush against said sidewall, said foil shield further including along selected portions thereof a longitudinally extending U-shaped intermediate section between said flanges and extending into said gap to urge said second flange against said sidewall in a cantilever-like action.

Claim 15

The cathode ray tube of claim 9 wherein said electron shield can be easily permanently deformed by hand by a person, and which after being pressed against said side wall will not have its elastic limit exceeded when deformed by 20 thousandths of an inch due to thermal expansion of said electrode.

Claim 16

A cathode ray tube having a central longitudinal axis and comprising: a. an envelope including a faceplate disposed centrally perpendicularly to said axis and a side wall extending substantially axially from the periphery of said faceplate, b. a mosaic screen of phosphor dots on said faceplate, c. electron gun means disposed within said envelope and adapted to project electrons toward said screen, d. a shadow mask electrode mounted within said envelope and surrounded by said side wall, said electrode comprising a frame and a multi-apertured sheet metal masking member mounted thereacross, said frame having an L-shaped cross-section with a transverse flange of the frame L disposed substantially perpendicularly to said axis and an axial flange of the frame L disposed substantially parallel to said axis and spaced by a gap from said side wall, and e. an electron shield comprising a strip of metal foil having first and second flanges extending along the length of the strip at the two longitudinal edges thereof, said first flange including integral tabs extending laterally therefrom, said shield being disposed with said first flange against said transverse frame flange and with said tabs extending inwardly toward said axis and crimped around the rim of said transverse frame flange, said second flange of said shield being disposed with a substantial portion lying flush against said sidewall.

Claim 17

A cathode ray tube having a central longitudinal axis and comprising: a. an envelope including a faceplate disposed centrally perpendicularly to said axis and a side wall extending substantially axially from the periphery of said faceplate, b. a mosaic screen of phosphor dots on said faceplate, c. electron gun means disposed within said envelope and adapted to project electrons toward said screen, d. a shadow mask electrode mounted within said envelope and surrounded by said side wall, said electrode comprising a frame and a multi-apertured sheet metal masking member mounted thereacross, said frame having an L-shaped cross-section with a transverse flange of the frame L disposed substantially perpendicularly to said axis and an axial flange of the frame L disposed substantially parallel to said axis and spaced by a gap from said side wall, and e. an electron shield comprising a strip of metal foil having first and second flanges extending along the length of the strip at the two longitudinal edges thereof, said first flange including integral tabs extending laterally therefrom, said shield being disposed with said first flange against said transverse frame flange and with said tabs extending inwardly toward said axis and crimped around the rim of said transverse frame flange, said second flange of said shield being disposed with a substantial portion lying flush against said sidewall.

Claim 18

A color television picture tube comprising an evacuated envelope having a panel including a curved viewing surface terminating in a peripheral wall and a funnel; a screen consisting of a plurality of different colored-light emitting phosphors deposited on the inside of said viewing surface; an aperture mask spaced a predetermined distance from said screen; a rigid frame supporting said mask; a plurality of mounting studs arranged about the interior of said peripheral wall; spring means for removably mounting said frame to said mounting studs; said frame necessarily being substantially smaller than said panel, and when in position, creating a peripheral gap between the edge of said frame and said wall; said gap being undesirable in that fortuitous electrons which overscan said frame may reach said screen and cause undesirable illumination of edge portions thereof; and a steel foil shield physically closing said gap between the wall and the frame, said steel foil shield being blackened to improve its heat radiation characteristics and being in thermal contact with said frame.

Claim 19

A color television picture tube comprising an evacuated envelope having a panel including a curved viewing surface terminating in a peripheral wall and a funnel; a screen consisting of a plurality of different colored-light emitting phosphors deposited on the inside of said viewing surface; an aperture mask spaced a predetermined distance from said screen; a rigid frame supporting said mask; a plurality of mounting studs arranged about the interior of said peripheral wall; spring means for removably mounting said frame to said mounting studs; said frame necessarily being substantially smaller than said panel, and when in position, creating a peripheral gap between the edge of said frame and said wall; said gap being undesirable in that fortuitous electrons which overscan said frame may reach said screen and cause undesirable illumination of edge portions thereof; and a steel foil shield physically closing said gap between the wall and the frame, said steel foil shield being blackened to improve its heat radiation characteristics and being in thermal contact with said frame.

Claim 20

A color television picture tube as set forth in claim 12, wherein said peripheral wall of the panel terminates in a seal edge for subsequent glass to glass sealing engagement with said funnel; said frame having a substantially L-shaped cross-section with a first leg parallel to and a second leg perpendicular to said peripheral wall; said frame, mask and shield when in assembled position being wholly within said panel for safer and more convenient handling during processing; said steel foil shield including a peripheral edge contoured toward said screen for snugly engaging said peripheral wall when in position, said shield also intimately contacting substantially the entire surface of said second leg to maximize heat transfer from said frame to said shield.

Claim 21

A color television picture tube comprising an evacuated envelope having a panel including a curved viewing surface terminating in a peripheral wall and a funnel; a screen consisting of a plurality of different colored light emitting phosphors deposited on the inside of said viewing surface; an aperture mask spaced a predetermined distance from said screen; a frame supporting said mask; a plurality of mounting studs arranged about the interior of said peripheral wall; spring means for mounting said frame to said mounting studs; said frame necessarily being substantially smaller than said panel, and when in position, creating a peripheral gap between the edge of said frame and said wall; said gap being undesirable in that fortuitous electrons which overscan said frame may reach said screen and cause undesirable illumination of edge portions thereof; and a metal foil shield physically closing said gap between the wall and the frame, said shield being blackened to improve its heat radiation characteristics and being in thermal contact with said frame.

Claim 22

A color television picture tube comprising an evacuated envelope having a panel including a curved viewing surface terminating in a peripheral wall and a funnel; a screen consisting of a plurality of different colored light emitting phosphors deposited on the inside of said viewing surface; an aperture mask spaced a predetermined distance from said screen; a frame supporting said mask; a plurality of mounting studs arranged about the interior of said peripheral wall; spring means for mounting said frame to said mounting studs; said frame necessarily being substantially smaller than said panel, and when in position, creating a peripheral gap between the edge of said frame and said wall; said gap being undesirable in that fortuitous electrons which overscan said frame may reach said screen and cause undesirable illumination of edge portions thereof; and a metal foil shield physically closing said gap between the wall and the frame, said shield being blackened to improve its heat radiation characteristics and being in thermal contact with said frame.

Claim 23

A color television picture tube as set forth in claim 14, wherein said peripheral wall of the panel terminates in a seal edge for subsequent glass to glass sealing engagement with said funnel; said frame having a substantially L-shaped cross-section with a first leg parallel to and a second leg perpendicular to said peripheral wall; said frame, mask and shield when in assembled position being wholly within said panel for safer and more convenient handling during processing; said shield including a peripheral edge having a contour similar to the inner surface of said peripheral wall for snugly engaging said wall when in position, said shield also intimately contacting substantially the entire surface of said second leg to maximize heat transfer from said frame to said shield.

Claim 24

A color television picture tube as set forth in claim 12, wherein said peripheral wall of the panel terminates in a seal edge for subsequent glass to glass sealing engagement with said funnel; said frame having a substantially L-shaped cross-section with a first leg parallel to and a second leg perpendicular to said peripheral wall; said frame, mask and shield when in assembled position being wholly within said panel for safer and more convenient handling during processing; said steel foil shield being sufficiently rigid to resist deformation by handling, and including a peripheral edge contoured toward said screen for snugly engagng said peripheral wall when in position, said shield also intimately contacting substantially the entire surface of said second leg to maximize heat transfer from said frame to said shield.

Claim 25

A color television picture tube as set forth in claim 12, wherein said peripheral wall of the panel terminates in a seal edge for subsequent glass to glass sealing engagement with said funnel; said frame having a substantially L-shaped cross-section with a first leg parallel to and a second leg perpendicular to said peripheral wall; said frame, mask and shield when in assembled position being wholly within said panel for safer and more convenient handling during processing; said steel foil shield including a peripheral edge contoured toward said screen for snugly engaging said peripheral wall when in position, said shield also intimately contacting substantially the entire surface of said second leg to maximize heat transfer from said frame to said shield.

Claim 26

In a color cathode-ray tube of the type having a glass envelope comprising a generally rectangular image screen panel section and a mating funnel section adapted to be sealed thereto, an interlaced pattern of different kinds of phosphor materials disposed on said screen, an electron gun means for developing at least one electron beam to be scanned across said screen, and a generally rectangular structural frame attached to said envelope but spaced therefrom and supporting a color selection electrode across the beam path of said tube between said screen and said gun means to determine the particular phosphor material impinged by said beam during the scanning of said screen: an improved electron shield bridging the space between said envelope and said frame to provide substantially complete prevention of electron access to said screen by way of said space notwithstanding the existence of relatively large manufacturing tolerances in said glass envelope section, said shield being impervious to electrons and being composed of a plurality of segments each separately fixed to said frame and each having a curved portion conforming to and separately indexed to a single corner of said rectangular panel section.

Claim 27

In a color cathode-ray tube of the type having a glass envelope comprising a generally rectangular image screen panel section and a mating funnel section adapted to be sealed thereto, an interlaced pattern of different kinds of phosphor materials disposed on said screen, an electron gun means for developing at least one electron beam to be scanned across said screen, and a generally rectangular structural frame attached to said envelope but spaced therefrom and supporting a color selection electrode across the beam path of said tube between said screen and said gun means to determine the particular phosphor material impinged by said beam during the scanning of said screen: an improved electron shield bridging the space between said envelope and said frame to provide substantially complete prevention of electron access to said screen by way of said space notwithstanding the existence of relatively large manufacturing tolerances in said glass envelope section, said shield being impervious to electrons and being composed of a plurality of segments each separately fixed to said frame and each having a curved portion conforming to and separately indexed to a single corner of said rectangular panel section.

Claim 28

An electron shield in accordance with claim 18, in which said shield is composed of four segments, and in which each of said curved portions overlaps the end of an adjacent segment.

Claim 29

In a color cathode-ray tube of the type having a glass envelope comprising a generally rectangular image screen panel section and a mating funnel section adapted to be sealed thereto, an interlaced pattern of different kinds of phosphor materials disposed on said screen, an electron gun means for developing at least one electron beam to be scanned across said screen, and a generally rectangular structural frame attached to said envelope but spaced therefrom and supporting a color selection electrode across the beam path of said tube between said screen and said gun means to determine the particular phosphor material impinged by said beam during the scanning of said screen: an improved electron shield bridging the space between said envelope and said frame to provide substantially complete prevention of electron access to said screen by way of said space notwithstanding the existence of relatively large manufacturing tolerances in said glass envelope section, said shield being impervious to electrons and being composed of a plurality of segments each separately fixed to said frame and each having a curved portion conforming to and indexed to one corner of said rectangular panel section.

Claim 30

In a color cathode-ray tube of the type having a glass envelope comprising a generally rectangular image screen panel section and a mating funnel section adapted to be sealed thereto, an interlaced pattern of different kinds of phosphor materials disposed on said screen, an electron gun means for developing at least one electron beam to be scanned across said screen, and a generally rectangular structural frame attached to said envelope but spaced therefrom and supporting a color selection electrode across the beam path of said tube between said screen and said gun means to determine the particular phosphor material impinged by said beam during the scanning of said screen: an improved electron shield bridging the space between said envelope and said frame to provide substantially complete prevention of electron access to said screen by way of said space notwithstanding the existence of relatively large manufacturing tolerances in said glass envelope section, said shield being impervious to electrons and being composed of a plurality of segments each separately fixed to said frame and each having a curved portion conforming to and indexed to one corner of said rectangular panel section.