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US 3,937,999 AGranted
Reduction of blanking requirements in a gaseous glow discharge display tube having a plurality of digits
AssigneeBeckman Instruments, Inc.
InventorDan J. Schott
Life of this patent
Estimating the term…
Abstract
A gaseous glow discharge display tube having a plurality of digits positioned within a common envelope is filled with a gas mixture of such a composition so as to reduce the blanking requirements for streamer elimination. Within a prescribed range of current densities, and applied voltage, blanking requirements may be entirely elininated.
Claims12
A multiple character multianode, raised planar cathode gaseous glow discharge display device adapted for multiplexed operation comprising
- a closed hermetically sealed planar envelope having a substantially flat non-conductive back base substrate and a front viewing window and containing a prescribed ionizable gas mixture,
- a plurality of electrically conductive cathode support pins passing in hermetically sealed relation through said substrate into the interior of said sealed envelope to terminate in a common plane parallel to and closely spaced from the interior surface of said substrate,
- the interior surface of said substrate having a plurality of cup shaped depressions formed therein, each said cup shaped depression surrounding a respective cathode support pin,
- a plurality of groups of flat strip-like raised planar cathodes, each group arranged in a character forming pattern and each cathode supported at the central region thereof on a respective pin end interior of said envelope so that the bottom flat surfaces of the cathodes lie in said common plane spaced from the interior surface of said substrate whereby glow is substantially eliminated from the bottom surfaces of said cathodes in operation of said device,
- said pins having portions exterior of said envelope for connecting corresponding cathodes in each said group to each other to enable electrical potential to be applied simultaneously thereto in multiplexed fashion, and
- plural, adjacent anode means disposed within said envelope in spaced relation to said cathodes;
- one anode means for each cathode group;
- said prescribed ionizable gas mixture comprising neon and argon with said argon constituting approximately from 0.1 percent to 0.8 percent of said mixture, said device cathodes being disposed at heights of from at least one to a few mils and operated at minimum current density and maximum anode-cathode voltage conditions on the order respectively of about one-tenth ampere per square inch and at about one hundred to two hundred volts;
- whereby in operation of said device the blanking interval utilized for streamer elimination is reduced to an arbitrarily small value in accordance with the anode-to-cathode voltage applied to said device and the current density through said cathodes as well as in accordance with electrode geometry and spacing.
6 more elements
A multiplexed multiple character multi-anode, raised planar cathode gaseous glow discharge display device comprising
- a plurality of groups of raised planar cathodes, each group arranged in a character forming pattern,
- connection means for electrically connecting corresponding cathodes in each group to each other to enable electrical potentials to be applied simultaneously to selected corresponding electrodes in each group,
- a plurality of operatively adjacent anodes operatively associated with said groups of cathodes respectively,
- means for individually energizing said anodes in a predetermined order,
- envelope means enclosing said cathodes and anodes, and
- a prescribed mixture within said envelope means comprising neon and argon with said argon constituting approximately from 0.1 percent to 0.8 percent of said mixture, said device cathodes being disposed at heights of from at least one to a few mils and operated at minimum current density and maximum anode-cathode voltage conditions on the order respectively of about one-tenth ampere per square inch and at about 100 to 200 volts;
- whereby in operation of said device the blanking interval utilized for streamer elimination is reduced to an arbitrarily small value in accordance with the voltage applied to said anodes and the current density through said cathodes as well as in accordance with electrode geometry and spacing.
4 more elements
Dependencies are inferred from the claim text.