Gas discharge display apparatus utilizing hollow cathode light sources

Claim 2

Gas discharge display apparatus comprising cathode means having a plurality of hollow cathode portions arranged in a predetermined pattern, anode means spaced from said cathode means and disposed adjacent said hollow portions but exterior thereof for minimizing interelectrode short-circuiting due to sputtering, gas-tight envelope means enclosing said hollow portions and said anode means with an ionizable gas, said envelope means having a transparent portion for viewing said hollow cathode portions, and connection means included in said cathode and anode means adapted for connection to a source of electrical potential to selectively apply suitable potentials between said anode and cathode means for providing electrical discharges in selected hollow cathode portions, said anode means being in such proximity to said hollow portions and said hollow portions having a depth such that only cathode glow discharges substantially confined thereto may occur thereby substantially confining sputtered cathodic material to the interiors of said hollow portions and defining sharply demarcated glow discharges, each said hollow cathode portion having side wall surfaces providing the primary electron emitting surfaces thereof, said side wall surfaces having low resistivity and said connecting means associated therewith providing a high conductance path from said side wall surfaces to said source of potential.

Claim 3

The apparatus recited in claim 1 in which said potentials comprise positive potentials at said anode means wIth respect to said cathode means.

Claim 4

The apparatus recited in claim 1 in which said cathode means comprises a first dielectric member having a plurality of holes arranged therein in a predetermined pattern, and a plurality of electrically conductive hollow cathodes having respective hollow portions therein, said cathodes being disposed in said holes in said first dielectric member respectively.

Claim 5

The apparatus recited in claim 3 further including a second member sealed to said first dielectric member thereby forming said envelope means.

Claim 6

The apparatus recited in claim 4 in which said second member comprises a transparent dielectric member for viewing said cathodes, and said anode means comprises a transparent electrically conductive film disposed on the surface of said transparent dielectric member internal to said envelope means.

Claim 7

The apparatus recited in claim 3 in which said cathodes comprise, respectively, electrically conductive rods having respective axial holes formed therein.

Claim 8

The apparatus recited in claim 6 in which said holes in said first dielectric member extend there-through, and said rods are hermetically sealed in said holes whereby portions thereof are exposed to the exterior of said envelope means for making electrical connection thereto and for efficient cooling thereof.

Claim 9

The apparatus recited in claim 6 further including, a source of positive electrical potential sufficient to ignite electrical discharges through said ionizable gas, and addressing means coupling said connection means to said source of electrical potential for applying said positive potential to said anode means with respect to selected ones of said plurality of rods thereby producing electrical discharges in selected holes of said rods.

Claim 10

The apparatus recited in claim 7 in which one of said rods comprises the sealed fill tube for said envelope means.

Claim 11

The apparatus recited in claim 1 in which said cathode means comprises an electrically conductive cathode member having a plurality of holes therein arranged in a predetermined pattern, and said anode means comprises a plurality of electrical conductors disposed adjacent said holes, respectively.

Claim 12

The apparatus recited in claim 10 further including a dielectric member sealed to said cathode member thereby forming said envelope means.

Claim 13

The apparatus recited in claim 11 in which said dielectric member comprises a transparent member for viewing said cathode member, and said electrical conductors comprise respective electrically conductive strips disposed on the surface of said transparent dielectric member internal to said envelope means.

Claim 14

The apparatus recited in claim 12 in which said strips are covered along their respective surfaces with a dielectric material except at those portions thereof adjacent said holes.

Claim 15

The apparatus recited in claim 12 further including a source of positive electrical potential sufficient to ignite electrical discharges through said ionizable gas, and addressing means coupling said connection means to said source of electrical potential for applying said positive potential to selected ones of said plurality of strips with respect to said conductive cathode member thereby producing electrical discharges in selected holes of said cathode member.

Claim 16

The apparatus recited in claim 1 in which said cathode means comprises a first dielectric member having a plurality of holes arranged therein in a matrix of rows and columns, and a plurality of electrically conductive hollow cathodes having respective hollow portions therein, said cathodes being disposed in said holes in said first dielectric member respectively.

Claim 17

The apparatus recited in claim 15 in which said anode means comprises a plurality of first electrical conductors each disposed adjacent the hollow portions of a respective column of said cathodes, and said cathode means includes a plurality of elEctrical row conductors each connecting the cathodes of a respective row.

Claim 18

The apparatus recited in claim 16 further including a second dielectric member sealed to said first dielectric member thereby forming said envelope means.

Claim 19

The apparatus recited in claim 17 in which said second dielectric member comprises a transparent member for viewing said cathodes, and said first electrical conductors comprise respective electrically conductive strips disposed on the surface of said transparent dielectric member internal to said envelope means.

Claim 20

The apparatus recited in claim 16 in which said cathodes comprise, respectively, electrically conductive rods having respective axial holes formed therein.

Claim 21

The apparatus recited in claim 19 in which said holes in said first dielectric member extend therethrough, said rods are hermetically sealed in said holes whereby portions thereof are exposed to the exterior of said envelope means, and said plurality of electrical row conductors are connected to said exposed portions.

Claim 22

The apparatus recited in claim 19 further including means for applying a positive potential to all of said first electrical conductors with respect to all of said row conductors sufficient to sustain electrical discharges through said ionizable gas, means for increasing the potential at a selected one of said first electrical conductors and for decreasing the potential at a selected one of said row conductors thereby producing a potential therebetween sufficient to ignite an electrical discharge in the hole associated with the intersection of said selected conductors, and means for decreasing the potential at a selected one of said first electrical conductors and for increasing the potential at a selected one of said row conductors thereby producing a potential therebetween sufficient to extinguish any electrical discharge sustained in the hole associated with the intersection of said selected conductors.

Claim 23

The apparatus recited in claim 20 in which one of said rods comprises the sealed fill tube for said envelope means.

Claim 24

The apparatus recited in claim 1 in which said cathode means comprises a plurality of electrically conductive cathode members each having a row of holes therein, said rows being aligned to form columns of holes, and said anode means comprises a plurality of first electrical conductors each disposed adjacent a respective column of said holes.

Claim 25

The apparatus recited in claim 23 in which said cathode members are sealed together with electrical insulator means disposed therebetween.

Claim 26

The apparatus recited in claim 24 further including a dielectric member sealed to said cathode members thereby forming said envelope means.

Claim 27

The apparatus recited in claim 25 in which said dielectric member comprises a transparent member for viewing said cathode members, and said first electrical conductors comprise respective electrically conductive strips disposed on the surface of said transparent member internal to said envelope means.

Claim 28

The apparatus recited in claim 26 in which each said cathode member includes a ridge between each pair of adjacent holes disposed therein, said ridges and said electrical insulator means extending to said surface of said transparent member internal to said envelope means thereby forming a barrier around each of said holes.

Claim 29

The apparatus recited in claim 26 further including means for applying a positive potential to all of said strips with respect to all of said cathode members sufficient to sustain electrical discharges through said ionizable gas, means for increasing the potential at a selected one of said strips and for decreasing the potential at a selected one of said cathode members thereby producing a potential between said selected strip and said selected cathode member sufficient to ignite an electrical discharge in the hole therein associated with said selected strip, and means for decreasing the potential at a selected one of said strips and for increasing the potential at a selected one of said cathode members thereby producing a potential between said selected strip and said selected cathode member sufficient to extinguish any electrical discharge sustained in the hole therein associated with said selected strip.

Claim 30

Gas discharge display apparatus comprising first cathode means having a plurality of first hollow cathode portions therein having first and second openings thereinto respectively, first anode means spaced from said first cathode means and disposed adjacent said first hollow portions, first gas-tight envelope means enclosing said first hollow portions and said first anode means with a first ionizable gas, said first envelope means including transparent portions adjacent said first and second openings respectively, second cathode means having a plurality of second hollow cathode portions therein having third and fourth openings thereinto respectively, second anode means spaced from said second cathode means and disposed adjacent said second hollow portions, second gas-tight envelope means enclosing said second hollow portions and said second anode means with a second ionizable gas, said second envelope means including transparent portions adjacent said third and fourth openings respectively, and connection means included in said cathode and anode means adapted for connection to a source of electrical potential to selectively apply suitable potentials between said anode and cathode means to produce electrical discharges in selected hollow cathode portions, said first and second cathode means being disposed adjacent each other with said first and second hollow portions being aligned whereby light emanating from said second and fourth openings enters said associated fourth and second openings respectively after transmission through said associated transparent portions disposed therebetween.

Claim 31

Gas discharge display apparatus comprising first cathode means having a plurality of first hollow cathode portions therein having first and second openings thereinto respectively, first anode means spaced from said first cathode means and disposed adjacent said first hollow portions, first gas-tight envelope means enclosing said first hollow portions and said first anode means with a first ionizable gas, said first envelope means including transparent portions adjacent said first and second openings respectively, second cathode means having a plurality of second hollow cathode portions therein having third and fourth openings thereinto respectively, second anode means spaced from said second cathode means and disposed adjacent said second hollow portions, second gas-tight envelope means enclosing said second hollow portions and said second anode means with a second ionizable gas, said second envelope means including transparent portions adjacent said third and fourth openings respectively, and connection means included in said cathode and anode means adapted for connection to a source of electrical potential to selectively apply suitable potentials between said anode and cathode means to produce electrical discharges in selected hollow cathode portions, said first and second cathode means being disposed adjacent each other with said first and second hollow portions being aligned whereby light emanating from said second and fourth openings enters said associated fourth and second openings respectively after transmission through said associated transparent portions disposed therebetween.

Claim 32

A gas discharge display element comprising an electrically conductive hollow cathode having a hollow portion therein, an electrically conductive anode spaced from said cathode and disposed adjacent said hollow portion, a transparent member hermetically sealed to said cathode forming a gas-tight envelope enclosing said hollow portion and said anode with an ionizable gas, and connection means adapted for connection to a source of electrical potential to selectively apply a suitable potential between said anode and cathode to produce an electrical discharge in said hollow portion, said hollow portion having side wall surfaces providing the primary electron emitting surfaces thereof, said side wall surfaces having low resistivity and said connecting means associated there-with providing a high conductance path from said side wall surfaces to said source of potential.

Claim 33

A gas discharge display element comprising an electrically conductive hollow cathode having a hollow portion therein, an electrically conductive anode spaced from said cathode and disposed adjacent said hollow portion, a transparent member hermetically sealed to said cathode forming a gas-tight envelope enclosing said hollow portion and said anode with an ionizable gas, and connection means adapted for connection to a source of electrical potential to selectively apply a suitable potential between said anode and cathode to produce an electrical discharge in said hollow portion, said hollow portion having side wall surfaces providing the primary electron emitting surfaces thereof, said side wall surfaces having low resistivity and said connecting means associated there-with providing a high conductance path from said side wall surfaces to said source of potential.

Claim 34

The apparatus recited in claim 30 in which said anode comprises a transparent electrically conductive film disposed on the surface of said transparent member internal to said envelope.

Claim 35

The apparatus recited in claim 30 in which said potential comprises a positive potential at said anode with respect to said cathode sufficient to ignite electrical discharge through said ionizable gas.

Claim 36

The apparatus recited in claim 30 in which said anode is in such proximity to said hollow portion that only cathode glow discharges substantially confined to said hollow portion may occur.