Method and apparatus for memory and display

Claim 3

In a plasma discharge device of the type having a gas sealed in a confined envelope area between a pair of dielectric coversheets, each coversheet having conductors thereon with the conductors being located opposite one another across the gas-filled space, so that ionization of the gas takes place when a predetermined voltage exists across the space between the conductors causing the gas to glow, an improvement including: the dielectric envelope being of a size capable of supporting a plurality of simultaneous glow discharges; means for applying voltage to the conductors; and the shape of the gas filled envelope relative to the shape of at least one of the conductors being such that the area of the gas filled space beneath the conductor varies in a predetermined manner along at least one conductor, so that the application of voltages of different magnitude by the voltage applying means causes discharges to take place in different portions of the envelope corresponding to a predetermined relationship of applied voltage to the gas filled area beneath the electrodes.

Claim 4

In a plasma discharge device of the type having a gas sealed in a confined envelope area between a pair of dielectric coversheets, each coversheet having conductors thereon with the conductors being located opposite one another across the gas-filled space, so that ionization of the gas takes place when a predetermined voltage exists across the space between the conductors causing the gas to glow, an improvement including: the dielectric envelope being of a size capable of supporting a plurality of simultaneous glow discharges; means for applying voltage to the conductors; and the shape of the gas filled envelope relative to the shape of at least one of the conductors being such that the area of the gas filled space beneath the conductor varies in a predetermined manner along at least one conductor, so that the application of voltages of different magnitude by the voltage applying means causes discharges to take place in different portions of the envelope corresponding to a predetermined relationship of applied voltage to the gas filled area beneath the electrodes.

Claim 5

An improved apparatus for display or memory, having a first and second dielectric coversheet spaced apart and sealed to form an envelope with a gas therein and at least one conductor on the first coversheet outside of the envelope and at least two conductors on the second coversheet outside of the envelope, means for selectively initiating a glow discharge in the gas between the conductor on the first coversheet and one of the conductors on the second coversheet, and means for continuously applying AC voltage between the conductor on the first coversheet and the conductors on the second coversheet, the AC voltage being of insufficient magnitude to initiate a glow discharge but of sufficient magnitude to sustain a glow discharge, wherein the improvement comprises: means for causing the AC voltage on the one of the conductors on the second coversheet to be reduced relative to the AC voltage on the other of the conductors on the second coversheet, thereby causing the glow discharge condition to migrAte from between the one conductor on the second coversheet and the conductor on the first coversheet to between the other conductor on the second coversheet and the conductor on the first coversheet.

Claim 6

An improved apparatus for display or memory, having a first and second dielectric coversheet spaced apart and sealed to form an envelope with a gas therein and at least one conductor on the first coversheet outside of the envelope and at least two conductors on the second coversheet outside of the envelope, means for selectively initiating a glow discharge in the gas between the conductor on the first coversheet and one of the conductors on the second coversheet, and means for continuously applying AC voltage between the conductor on the first coversheet and the conductors on the second coversheet, the AC voltage being of insufficient magnitude to initiate a glow discharge but of sufficient magnitude to sustain a glow discharge, wherein the improvement comprises: means for causing the AC voltage on the one of the conductors on the second coversheet to be reduced relative to the AC voltage on the other of the conductors on the second coversheet, thereby causing the glow discharge condition to migrAte from between the one conductor on the second coversheet and the conductor on the first coversheet to between the other conductor on the second coversheet and the conductor on the first coversheet.

Claim 7

An improved apparatus for display or memory, having first and second dielectric coversheets spaced apart and sealed to form an envelope with a gas therein and at least one conductor on the first coversheet outside of the envelope and at least a first conductor and a second conductor on the second coversheet outside of the envelope, means for selectively initiating a glow discharge in the gas between the conductor on the first coversheet and the first conductor on the second coversheet, and means for continuously applying an AC voltage between the conductor on the first coversheet and the first and second conductors on the second coversheet, the AC voltage being of insufficient magnitude to initiate a glow discharge but of sufficient magnitude to sustain a glow discharge, wherein the improvement comprises: means for changing the AC voltage applied between the first conductor on the second coversheet and the conductor on the first coversheet relative to the AC voltage applied between the second conductor on the second coversheet and the conductor on the first coversheet to cause the instantaneous voltage applied to the second conductor on the second coversheet to reach the magnitude sufficient to maintain a glow discharge sooner than the instantaneous voltage applied to the first conductor on the second coversheet reaches the magnitude sufficient to maintain a glow discharge, thereby causing the glow discharge condition to migrate from between the first conductor on the second coversheet and the conductor on the first coversheet to between the second conductor on the second coversheet and the conductor on the first coversheet.

Claim 8

An improved apparatus for display or memory, having first and second dielectric coversheets spaced apart and sealed to form an envelope with a gas therein and at least one conductor on the first coversheet outside of the envelope and at least a first conductor and a second conductor on the second coversheet outside of the envelope, means for selectively initiating a glow discharge in the gas between the conductor on the first coversheet and the first conductor on the second coversheet, and means for continuously applying an AC voltage between the conductor on the first coversheet and the first and second conductors on the second coversheet, the AC voltage being of insufficient magnitude to initiate a glow discharge but of sufficient magnitude to sustain a glow discharge, wherein the improvement comprises: means for changing the AC voltage applied between the first conductor on the second coversheet and the conductor on the first coversheet relative to the AC voltage applied between the second conductor on the second coversheet and the conductor on the first coversheet to cause the instantaneous voltage applied to the second conductor on the second coversheet to reach the magnitude sufficient to maintain a glow discharge sooner than the instantaneous voltage applied to the first conductor on the second coversheet reaches the magnitude sufficient to maintain a glow discharge, thereby causing the glow discharge condition to migrate from between the first conductor on the second coversheet and the conductor on the first coversheet to between the second conductor on the second coversheet and the conductor on the first coversheet.

Claim 9

An apparatus according to claim 4 wherein the changing means comprises means for reducing the AC voltage applied to the first conductor on the second cover-sheet relative to the AC voltage applied to the second conductor on the second coversheet while continuing to maintain the relatively reduced AC voltage at a magnitude sufficient to sustain a discharge.

Claim 10

An apparatus according to claim 5 wherein the reducing means comprises means for holding constant the AC voltage applied to the first conductor on the second coversheet and means for increasing the AC voltage applied to the second conductor on the second coversheet.

Claim 11

An apparatus according to claim 5 wherein the reducing means comprises means for holding constant the AC voltage applied to the second conductor on the second coversheet and means for decreasing the AC voltage applied to the first conductor on the second coversheet.

Claim 12

An apparatus according to claim 5 wherein the reducing means comprises means for decreasing the AC voltage applied to the first conductor on the second coversheet and means for increasing the AC voltage applied to the second conductor to the second coversheet.

Claim 13

An apparatus according to claim 4 wherein the changing means comprises means for varying the phase of the AC voltages to cause the instantaneous voltage applied to the second conductor on the second coversheet to rise sooner than the instantaneous voltage applied to the first conductor on the second coversheet.

Claim 14

An apparatus according to claim 9 wherein the varying means comprises means for holding steady the AC voltage applied to the first conductor on the second coversheet and means for advancing the AC voltage applied to the second conductor on the second coversheet.

Claim 15

An apparatus according to claim 9 wherein the varying means comprises means for holding steady the AC voltage applied to the second conductor on the second coversheet and means for retarding the AC voltage applied to the first conductor on the second coversheet.

Claim 16

An apparatus according to claim 9 wherein the varying means comprises means for retarding the AC voltage applIed to the first conductor on the second coversheet and means for advancing the AC voltage applied to the second conductor on the second coversheet.

Claim 17

An apparatus according to claim 4 wherein at least the second conductor on the second coversheet is generally tapered, having a narrow end and a wide end.

Claim 18

An apparatus according to claim 13 wherein the conductors on the second coversheet are positioned with the narrow end of the tapered second conductor adjacent but not touching the first conductor.

Claim 19

An apparatus according to claim 14 wherein the second conductor is one of a plurality of electrically-connected, generally tapered electrode segments arranged in a line on the second coversheet; and wherein the first conductor is one of a plurality of electrically-connected, generally tapered electrode segments arranged in a line on the second coversheet.

Claim 20

An apparatus according to claim 15 wherein the wide ends of the tapered electrode segments of the first conductor are positioned adjacent but not touching the narrow ends of the tapered electrode segments of the second conductor and the wide ends of the tapered electrode segments of the second conductor are positioned adjacent but not touching the narrow ends of the tapered electrode segments of the first conductor.

Claim 21

An apparatus according to claim 16 further comprising a third conductor on the second coversheet positioned adjacent the wide end of one of the tapered segments on the second coversheet and means for transferring a glow discharge condition from the one tapered segment to the third conductor; the third conductor being tapered, having a wide end and a narrow end, with the narrow end of the third conductor positioned adjacent to but not touching the one tapered segment; and the third conductor being one of a plurality of electrically connected, generally tapered electrode segments arranged in a line perpendicular to the lines of the first and second conductors.

Claim 22

An apparatus according to claim 17 further comprising a plurality of fourth tapered, electrically-connected conductors on the second coversheet arranged in a line parallel with the line of the third conductor; and the fourth conductors being electrically connected to one of the other conductors on the second coversheet.

Claim 23

A shift register for moving data bits generally in a line comprising: a dielectric, gas-filled envelope having two sides; a first pair of conductors on the outside of one side of the envelope, extending parallel to each other and generally along the line; a plurality of orthogonal conductors on the outside of the envelope and on the other side of the envelope and extending generally perpendicular to the first pair of conductors; a plurality of ignition electrodes selectively arranged in a row on the outside of the envelope parallel with the line; means for applying an AC voltage to the ignition electrodes, the magnitude of the AC voltage being sufficient to initiate a plasma discharge at each ignition electrode and within the envelope; means for applying AC voltage between at least one of the first pair of conductors and at least one of the orthogonal conductors, the magnitude of AC voltage being sufficient to sustain a plasma discharge but insufficient to initiate a plasma discharge; and means for controlling the AC voltage applied to the conductors for causing the plasma discharge to progress between the first pair of conductors and the orthogonal conductors generally along the line.

Claim 24

A shift register for moving data bits generally in a line comprising: a dielectric, gas-filled envelope having two sides; a first pair of conductors on the outside of one side of the envelope, extending parallel to each other and generally along the line; a plurality of orthogonal conductors on the outside of the envelope and on the other side of the envelope and extending generally perpendicular to the first pair of conductors; a plurality of ignition electrodes selectively arranged in a row on the outside of the envelope parallel with the line; means for applying an AC voltage to the ignition electrodes, the magnitude of the AC voltage being sufficient to initiate a plasma discharge at each ignition electrode and within the envelope; means for applying AC voltage between at least one of the first pair of conductors and at least one of the orthogonal conductors, the magnitude of AC voltage being sufficient to sustain a plasma discharge but insufficient to initiate a plasma discharge; and means for controlling the AC voltage applied to the conductors for causing the plasma discharge to progress between the first pair of conductors and the orthogonal conductors generally along the line.

Claim 25

A shift register according to claim 19 further comprising a second shift register arranged generally in a second line intersecting the line of the first shift register and arranged so that a bit-representing plasma discharge progressing along the line on the first shift register is transferred to the second shift register and progresses along the second line on the second shift register.

Claim 26

A shift register according to claim 19 further comprisiNg: a second pair of conductors on the outside of the envelope cooperating with the orthogonal conductors and extending parallel with the first pair of conductors with each conductor of the second pair of conductors associated with a corresponding one of the first pair of conductors; and means for receiving a plasma discharge from the first pair of conductors and in response thereto for initiating progression of the plasma discharge on the second pair of conductors generally along a second line parallel with the line of the first pair of conductors comprising a shift register folded on itself.

Claim 27

A display device comprising: a dielectric, gas-filled envelope; a plurality of shift registers comprising conductors on the outside of the envelope for moving data-bit-representing plasma discharges generally along substantially parallel lines; means associated with each shift register for selectively initiating plasma discharges in the shift registers; a manifold shift register arranged along a line intersecting the parallel lines for receiving plasma discharges from the shift registers and for moving the plasma discharges generally along the intersecting line; and means for receiving plasma discharges from the manifold shift register and for visually displaying the plasma discharges.

Claim 28

A display device comprising: a dielectric, gas-filled envelope; a plurality of shift registers comprising conductors on the outside of the envelope for moving data-bit-representing plasma discharges generally along substantially parallel lines; means associated with each shift register for selectively initiating plasma discharges in the shift registers; a manifold shift register arranged along a line intersecting the parallel lines for receiving plasma discharges from the shift registers and for moving the plasma discharges generally along the intersecting line; and means for receiving plasma discharges from the manifold shift register and for visually displaying the plasma discharges.

Claim 33

A method according to claim 24 wherein the causing step comprises reducing the magnitude of the AC voltage applied between the first pair of conductors with respect to the AC voltage applied between the second pair of conductors so that the magnitude of the AC voltage between the first pair of conductors is less than the magnitude of the AC voltage between the second pair of conductors but still sufficient to maintain a memory condition.

Claim 34

A method according to claim 25 wherein the reducing is accomplished by holding constant the AC voltage applied between the first pair of conductors and increasing the AC voltage applied between the second pair of conductors.

Claim 35

A method according to claim 25 wherein the causing step further comprises varying the phase of the AC voltages simultaneously with reducing the magnitude of the AC voltage applied between the first pair of conductors with respect to the second pair of conductors to cause the voltage applied between the second pair of conductors to rise sooner than the voltage applied between the first pair of conductors.

Claim 36

A method according to claim 24 wherein the causing step comprises varying the phase of the AC voltages to cause the instantaneous voltage applied between the second pair of conductors to rise sooner than the instantaneous voltage applied between the first pair of conductors.

Claim 37

An improved method of controlling a display or memory device having first and second dielectric coversheets spaced apart and sealed to form an envelope with a gas therein, a first conductor and a second conductor arranged parallel to each other on the first coversheet outside of the envelope, a third conductor and a fourth conductor arranged parallel to each other on the second coversheet outside of the envelope, the third and fourth conductors arranged perpendicular to and overlapping the first and second conductors, means for selectively initiating a glow discharge in the gas between the first conductor and the third conductor, means for continuously applying an AC signal to the first and second conductors, and means for applying an AC voltage to the third and fourth conductors, the AC voltage applied to the conductors on the second coversheet being substantially 180* out of phase with the AC voltage applied to the conductors on the first coversheet so as to produce AC voltage difference between the conductors on the first coversheet and the conductors on the second coversheet which AC voltage difference has a maximum magnitude equal to the sum of the peak-to-peak voltages of the AC voltages applied to the conductors on the two coversheets, the maximum magnitude of the AC voltage difference between the conductors on the first coversheet and the conductors on the second coversheet being of insufficient magnitude to initiate a glow discharge in the gas but of sufficient magnitude to sustain a glow discharge in the gas, wherein the improved method comprises: controlling the AC voltages applied to the first and second conductors so that the instantaneous voltage difference between the first conductor and at least one of the conductors on the second coversheet reaches an instantaneous magnitude sufficient to sustain glow discharge in the gas sooner than the instantaneous AC voltage applied between the second conductor and the conductors on the second coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas; controlling the AC voltages applied to the third and fourth conductors so that the instantaneous voltage difference between the third conductor and at least one of the conductors on the first coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas sooner than the instantaneous AC voltage applied between the fourth conductor and the conductors on the first coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas; and changing the AC voltages applied to the third and fourth conductors to cause the instantaneous voltage difference between the fourth conductor and at least one of the conductors on the first coversheet to reach an instantaneous magnitude sufficient to sustain a glow discharge in the gas sooner than the instantaneous AC voltage applied between the third conductor and the condUctors on the first coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas, thereby moving the glow discharge condition from between the first and third conductors to between the first and fourth conductors.

Claim 38

An improved method of controlling a display or memory device having first and second dielectric coversheets spaced apart and sealed to form an envelope with a gas therein, a first conductor and a second conductor arranged parallel to each other on the first coversheet outside of the envelope, a third conductor and a fourth conductor arranged parallel to each other on the second coversheet outside of the envelope, the third and fourth conductors arranged perpendicular to and overlapping the first and second conductors, means for selectively initiating a glow discharge in the gas between the first conductor and the third conductor, means for continuously applying an AC signal to the first and second conductors, and means for applying an AC voltage to the third and fourth conductors, the AC voltage applied to the conductors on the second coversheet being substantially 180* out of phase with the AC voltage applied to the conductors on the first coversheet so as to produce AC voltage difference between the conductors on the first coversheet and the conductors on the second coversheet which AC voltage difference has a maximum magnitude equal to the sum of the peak-to-peak voltages of the AC voltages applied to the conductors on the two coversheets, the maximum magnitude of the AC voltage difference between the conductors on the first coversheet and the conductors on the second coversheet being of insufficient magnitude to initiate a glow discharge in the gas but of sufficient magnitude to sustain a glow discharge in the gas, wherein the improved method comprises: controlling the AC voltages applied to the first and second conductors so that the instantaneous voltage difference between the first conductor and at least one of the conductors on the second coversheet reaches an instantaneous magnitude sufficient to sustain glow discharge in the gas sooner than the instantaneous AC voltage applied between the second conductor and the conductors on the second coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas; controlling the AC voltages applied to the third and fourth conductors so that the instantaneous voltage difference between the third conductor and at least one of the conductors on the first coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas sooner than the instantaneous AC voltage applied between the fourth conductor and the conductors on the first coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas; and changing the AC voltages applied to the third and fourth conductors to cause the instantaneous voltage difference between the fourth conductor and at least one of the conductors on the first coversheet to reach an instantaneous magnitude sufficient to sustain a glow discharge in the gas sooner than the instantaneous AC voltage applied between the third conductor and the condUctors on the first coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas, thereby moving the glow discharge condition from between the first and third conductors to between the first and fourth conductors.

Claim 39

A method according to claim 29 further comprising the step of changing the AC voltages applied to the first and second conductors to cause the instantaneous voltage difference between the second conductor and at least one of the conductors on the second coversheet to reach an instantaneous magnitude sufficient to sustain a glow discharge in the gas sooner than the instantaneous AC voltage applied between the first conductor and the conductors on the second coversheet reaches an instantaneous magnitude sufficient to sustain a glow discharge in the gas, thereby moving the glow discharge condition from between the first and fourth conductors to between the second and fourth conductors.