Patent US3742483A successfully refreshed from Google Patents.
US3742483A
Expired / Lapsed
US
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Video display system using display panel
Assignee: Unisys Corp
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Filing: 1971-06-01
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Granted: 1973-06-26
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Expires: 1991-06-01
Abstract
Abstract The system operates with a display panel comprising a large number of small dot-like gas-filled cells, each of which has a drive circuit which can be energized to pass current therethrough to cause the cell to glow. The system includes means for applying both a video signal and a control signal to the driver circuit to thereby control the amplitude and time duration of the current flowing through a cell. This controls the cell brightness. Another system includes (1) a driver circuit to which a varying voltage is applied to cause a varying current to pass therethrough to a cell and (2) a voltage comparator which combines the video signal and a control signal to control the time duration of said varying voltage applied to the driver and thus the time duration of said varying current. This also controls the cell brightness.
Inventors
- 👤 J Ogle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:29
CPC Classifications
H; H01; H01J; H01J17/00; H01J17/38; H01J17/48; H01J17/49; H01J17/492; H01J17/494; G; G09; G09G; G09G3/00; G09G3/20; G09G3/22; G09G3/28; G09G3/282; G09G3/285
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
124 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a current source connected to said panel and adapted to pass current through said cells, a source of video signals connected to said current source, and a source of control signals connected to said current source for modifying the character of said video signals, the relationship between the amplitudes and shapes of said video signals and said control signals determining the amplitude and time duration of current flow Through a cell and the brightness at which the cell glows.
Claim 2
Independent Claim
124 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a current source connected to said panel and adapted to pass current through said cells, a source of video signals connected to said current source, and a source of control signals connected to said current source for modifying the character of said video signals, the relationship between the amplitudes and shapes of said video signals and said control signals determining the amplitude and time duration of current flow Through a cell and the brightness at which the cell glows.
Claim 3
Independent Claim
133 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a transistor current source having its collector connected to said panel and adapted to pass current through said cell, a source of video signals coupled to the base of said transistor current source, and a source of control signals connected to the emitter of said current source, the relationship between the amplitudes and shapes of said video signals and said control signals determining the turn-off of said transistor and the amplitude and time duration of current flow through a cell and the brightness at which the cell glows.
Claim 4
Independent Claim
133 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a transistor current source having its collector connected to said panel and adapted to pass current through said cell, a source of video signals coupled to the base of said transistor current source, and a source of control signals connected to the emitter of said current source, the relationship between the amplitudes and shapes of said video signals and said control signals determining the turn-off of said transistor and the amplitude and time duration of current flow through a cell and the brightness at which the cell glows.
Claim 5
Dependent Claim
44 words
The system defined in claim 2 wherein said panel includes an anode electrode associated with each row of cells and a cathode electrode associated with each column of cells, and a separate transistor current source is coupled by its collector to each anode electrode.
Claim 6
Dependent Claim
47 words
The system defined in claim 3 wherein an optical scanning device generates said video signals and one of said devices is coupled to each of said transistor current sources, said source of control signals being coupled to the emitter electrodes of all of said transistors in common.
Claim 7
Independent Claim
136 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a current source connected to said panel and adapted to pass a current wave through said cell, a switch coupled to said current source, a voltage comparator, a source of video signals and a source of control signals, both coupled to said voltage comparator, said comparator functioning when the voltages of said video signal and said control signal are equal, to operate said switch and thereby to turn off said current source whereby the amplitude and time duration of the current flow through a cell and the cell brightness are limited.
Claim 8
Independent Claim
136 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a current source connected to said panel and adapted to pass a current wave through said cell, a switch coupled to said current source, a voltage comparator, a source of video signals and a source of control signals, both coupled to said voltage comparator, said comparator functioning when the voltages of said video signal and said control signal are equal, to operate said switch and thereby to turn off said current source whereby the amplitude and time duration of the current flow through a cell and the cell brightness are limited.
Claim 9
Dependent Claim
15 words
The system defined in claim 5 wherein said current wave is of generally sawtooth form.
Claim 10
Dependent Claim
39 words
The system defined in claim 5 wherein said panel includes an anode electrode associated with each row of cells and a cathode associated with each column of cells, and a separate current source is coupled to each anode electrode.
Claim 11
Dependent Claim
15 words
The system defined in claim 5 wherein said control signals are generally sawtooth voltage waves.
Claim 12
Dependent Claim
24 words
The system defined in claim 5 wherein said control signals are generally sawtooth voltage waves and said current wave is of generally sawtooth form.
Claim 13
Dependent Claim
28 words
The system defined in claim 5 wherein an optical scanning device generates said video signals and one of said devices is coupled to each of said current sources.
Claim 14
Independent Claim
135 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a transistor current source having its collector connected to said panel and adapted to pass current through said cell, a source of video signals coupled to the base of said transistor current source, and a source of generally sawtooth control signals connected to the emitter of said current source, the relationship between the amplitudes and shapes of said video signals and said control signals determining the turn-off of said transistor and the amplitude and time duration of current flow through a cell and the brightness at which the cell glows.
Claim 15
Independent Claim
135 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a transistor current source having its collector connected to said panel and adapted to pass current through said cell, a source of video signals coupled to the base of said transistor current source, and a source of generally sawtooth control signals connected to the emitter of said current source, the relationship between the amplitudes and shapes of said video signals and said control signals determining the turn-off of said transistor and the amplitude and time duration of current flow through a cell and the brightness at which the cell glows.
Claim 16
Independent Claim
209 words
A system for operating a display panel comprising a plurality of rows an columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a transistor current source connected to said panel and adapted to pass current through each said cell, a source of a first generally sawtooth signal coupled to said transistor and controlling the amplitude of current flow through each said cell, with the glow brightness being proportional to the amplitude of the current flow and the amplitude of current flow being proportional to the portion of said sawtooth signal applied to said transistor, a voltage comparator coupled to said transistor and controlling the application of said sawtooth signal to said transistor, a source of video signals and a source of second generally sawtooth control signals, both coupled to said voltage comparator, said comparator functioning when the voltages of said video signal and said control signal are equal to turn off said transistor, the turn-off time of said transistor occurring at some point on said first sawtooth signal which determines the amplitude and time duration of the current flow through a cell and the cell brightness.
Claim 17
Independent Claim
209 words
A system for operating a display panel comprising a plurality of rows an columns of gas-filled cells, each of which can be turned on and caused to glow by the passage of current between first and second electrodes associated with each cell, said system comprising a transistor current source connected to said panel and adapted to pass current through each said cell, a source of a first generally sawtooth signal coupled to said transistor and controlling the amplitude of current flow through each said cell, with the glow brightness being proportional to the amplitude of the current flow and the amplitude of current flow being proportional to the portion of said sawtooth signal applied to said transistor, a voltage comparator coupled to said transistor and controlling the application of said sawtooth signal to said transistor, a source of video signals and a source of second generally sawtooth control signals, both coupled to said voltage comparator, said comparator functioning when the voltages of said video signal and said control signal are equal to turn off said transistor, the turn-off time of said transistor occurring at some point on said first sawtooth signal which determines the amplitude and time duration of the current flow through a cell and the cell brightness.
Claim 18
Independent Claim
302 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, a cathode electrode aligned with each column of cells and an anode electrode aligned with each row of cells, each cell being capable of being turned on and caused to glow by the passage of current between a cathode and an anode electrode associated with each cell, said system comprising a transistor current source connected to each said anode electrode and adapted to pass a current wave through a selected cell when a selected cathode is also energized, a source of generally sawtooth control signals coupled to each said transistor current source for controlling the amplitude of current flow through said cells, with the glow brightness being proportional to the amplitude of the current flow and the amplitude of current flow being proportional to the portion of said sawtooth signal applied to said transistor, a voltage comparator coupled to each transistor current source, a plurality of sources of video signals, each coupled to one of said voltage comparators, and a single source of generally sawtooth control signals coupled to all of said voltage comparators, each voltage comparator providing an output signal to operate its current source when the relationship between its video signal and sawtooth control voltage are such that there is an output from the voltage comparator, each voltage comparator providing no output when the applied video signal and sawtooth control signal are equal in amplitude whereupon the associated transistor current source is turned off and any associated gas cell which has been ON is turned OFF after having reached a level of brightness determined by the length of time its current source had been ON, said length of time being determined by the relationship between the video signal and the sawtooth control signal.
Claim 19
Independent Claim
302 words
A system for operating a display panel comprising a plurality of rows and columns of gas-filled cells, a cathode electrode aligned with each column of cells and an anode electrode aligned with each row of cells, each cell being capable of being turned on and caused to glow by the passage of current between a cathode and an anode electrode associated with each cell, said system comprising a transistor current source connected to each said anode electrode and adapted to pass a current wave through a selected cell when a selected cathode is also energized, a source of generally sawtooth control signals coupled to each said transistor current source for controlling the amplitude of current flow through said cells, with the glow brightness being proportional to the amplitude of the current flow and the amplitude of current flow being proportional to the portion of said sawtooth signal applied to said transistor, a voltage comparator coupled to each transistor current source, a plurality of sources of video signals, each coupled to one of said voltage comparators, and a single source of generally sawtooth control signals coupled to all of said voltage comparators, each voltage comparator providing an output signal to operate its current source when the relationship between its video signal and sawtooth control voltage are such that there is an output from the voltage comparator, each voltage comparator providing no output when the applied video signal and sawtooth control signal are equal in amplitude whereupon the associated transistor current source is turned off and any associated gas cell which has been ON is turned OFF after having reached a level of brightness determined by the length of time its current source had been ON, said length of time being determined by the relationship between the video signal and the sawtooth control signal.
Claim 20
Dependent Claim
101 words
The system defined in claim 13 wherein said source of control signals comprises a source of generally rectangular pulses, an integrating circuit for converting said pulses to sawtooth waves, said integrating circuit being connected to a first amplifier for controlling the amplitude and reference level of said sawtooth waves, the output of said first amplifier being coupled to the emitters of all the anode current sources, said integrating circuit also being connected through a second amplifier to a second integrating circuit, and then to a third amplifier, the output of which is coupled to one input of said voltage comparator circuit.
Claim 21
Dependent Claim
126 words
The system defined in claim 13 wherein said source of control signals comprises a source of generally rectangular pulses, an integrating circuit for converting said pulses to sawtooth waves, said integrating circuit being connected to a first amplifier for controlLing the amplitude and reference level of said sawtooth waves, the output of said first amplifier being coupled to the emitters of all the anode current sources, said integrating circuit also being connected through a second amplifier to a second integrating circuit, and then to a third amplifier, the output of which is coupled to one input of said voltage comparator circuit, and a potentiometer coupled to the input of said second amplifier and usable to change the shape of the pulses applied to said third amplifier.
Claim 22
Dependent Claim
96 words
The system defined in claim 13 wherein each said transistor current source includes base, emitter, and collector electrodes and including a bus connected to the output of said source of control signals, a connection from said bus to the emitter of each of said transistor current sources, the base of each transistor current source being connected to the output of its voltage comparator, one input of said voltage comparator being connected to a source of video signals and the other input of said voltage comparator being connected to an output from said source of control signals.
Claim 23
Dependent Claim
183 words
The system defined in claim 13 wherein each said transistor current source includes base, emitter, and collector electrodes and including a bus connected to the output of said source of control signals, a connection from said bus to the emitter of each of said transistor current sources, the base of each transistor current source being connected to the output of its voltage comparator, one input of said voltage comparator being connected to a source of video signals and the other input of said voltage comparator being connected to an output from said source of control signals, said source of control signals comprising a source of generally rectangular pulses, an integrating circuit for converting said pulses to sawtooth waves, said integrating circuit being connected to a first amplifier for setting the D.C. level of said sawtooth waves and from there to said bus connected to the emitters of all of said transistor current sources, said integrating circuit also being connected through a second amplifier to a second integrating circuit to a third amplifier and then to said other input of said voltage comparator circuit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |