US3892998A

US3892998A - Gas discharge device for multicolor information display

Info

Publication number: US3892998A
Application number: US410009A
Authority: US
Inventors: Frank Tsui; Katherine Tsui
Original assignee: International Business Machines Corp
Current assignee: International Business Machines Corp
Priority date: 1972-10-25
Filing date: 1973-10-25
Publication date: 1975-07-01
Anticipated expiration: 1992-07-01
Also published as: FR2204876B1; JPS4975265A; JPS5639018B2; FR2204876A1; DE2252256A1; GB1440607A

Abstract

A gas discharge display/storage apparatus in which a multicolor display is achieved utilizing an arrangement of the triad cell configuration. The triad cell configuration may be positioned on a transparent filter sheet or may be represented by polychromatic phosphor cells formed on the inner surface of the gas discharge display storage apparatus. The triad arrangement representing basic colors of red, blue and green is addressed by horizontal conductors which thread through each of the three cells in the triad arrangement, while the vertical conductors are arrayed in groups of three, each conductor threading the cells of a specific color. The panel can thereby be constructed substantially as a conventional black and white plasma display device, and conventional addressing techniques may be utilized to provide a plasma display with multicolor capability.

Description

[451 July 1,1975

3,790,841 2/1974 Tsui et a1. 313/108 B GAS DISCHARGE DEVICE FOR MULTICOLOR INFORMATION DISPLAY [75] Inventors: Frank Tsui; Katherine Tsui, both of Primary Examiner mfred Smith Assistant ExaminerWm. H. Punter Boeblingen, Germany [57] ABSTRACT A gas discharge display/storage apparatus in which a s e .m h Y MN k fin .m mm BA M nm .mfi mm mm. er m0 IC e e n g m s A 1 3 7 l 221 Filed: Oct. 25, 1973 0211 Appl. No: 410,009

multicolor display is achieved utilizing an arrangement of the triad cell configuration. The triad cell configuration may be positioned on a transparent filter sheet 3 Foreign Applicafion Priority Data or may be represented by polychromatic phosphor Oct 25 1972 cells formed on the inner surface of the gas discharge ngement rep- Germany..................,......... 2252256 display storage apparatus. The triad arra resenting basic colors of red, blue and green is addressed by horizontal conductors which thread through each of the three cells in the triad arrange- 313/491 H0lj 61/08; HOlj 61/40; 1101 1/74 Field of Search............

313/108 A 108 B '88 ment, while the vertical conductors are arrayed in 313/217 92 PH 408 groups of three, each conductor threading the cells of a specific color. The panel can thereby be constructed substantially as a conventional black and white plasma References Cited UNITED STATES PATENTS display device, and conventional addressing techniques may be utilized to provide a plasma display with multicolor capability.

313/108 B X 313/217 313/ 188 X 6 Claims, 6 Drawing Figures 3,059,145 3,735,182 Dalton et a1... 3,771,008 Chen et al KENS SHEET w QE GAS DISCHARGE DEVICE FOR MULTICOLOR INFORMATION DISPLAY C ROSS-REFERENCE TO RELATED APPLICATIONS Application Ser. No. 323,585, filed Jan. I5, 1973, by F. Tsui and K. Tsui, for Gas Discharge Display Field for Multicolor Display" now U.S. Pat. No. 3,790,841.

U.S. application Ser. No. 405,205 filed Oct. 10, I973, now U.S. Pat. No. 3,837,724 a continuation of application Ser. No. 214,348 filed Dec. 30, 1971, by P. H. Haberland et al., for Gas Panel Fabrication" now abandoned.

Application Ser. No. 372,384 filed June 21, 1973, by T. N. Criscimagna et al., for Method and Apparatus for Gas Display Panel.

BACKGROUND OF THE INVENTION In gaseous discharge or plasma display devices, as the development phase of the conventional black and white display apparatus has effectively terminated, increasing attention is being devoted to different techniques for implementing a multicolor gaseous discharge device. One method of providing such a display is described in referenced U.S. Pat. No. 3,790,841, which is characterized in that at least two discharge spaces are provided which are separated from each other in the direction of discharge, that the conductors of a conductor field pair are disposed at an angle of about 60 in relation to each other, that the conductors of all conductor field pairs are disposed in three directions differing from each other by about 60, that in each of these directions discharge cells for two of the three basic colors are alternately arranged, one discharge cell for one basic color being common to two directions. One disadvantage of this arrangement is that the apparatus while utilizing charge storage techniques is very complex in that it effectively incorporates two discharge panels in a single assembly and three separate sets of conductors are required to drive this assembly.

SUMMARY OF THE INVENTION It is an object of the present invention to avoid the disadvantages still existing in the above-specified U.S. Pat. No. 3,790,841. A multicolor display with one single common discharge space for all basic colors involved and/or for their mixed colors is to be achieved. Only two fields of substantially parallel electric conductors are to be provided, instead of more than two.

Compared with the above-mentioned prior U.S. Pat. No. 3,790,841, this would have the advantage that the two conductor fields can be designed with individual conductors arranged orthogonally to each other at the display spots, using a single discharge space.

The subject invention effectively combines a novel technique for achieving color with conventional black and white plasma display techniques to achieve a multicolor display. The triad arrangement of colored cells when selectively excited emit light in the basic colors of red, blue or green. The individual cells are coincidently selected by horizontal and vertical selection circuits, the horizontal conductors being threaded through each cell of an associated triad in meandering form each of the vertical conductors being threaded through separate cells representing one of the three basic colors.

5 the application of elements which emit or reflect light in the basic colors or combinations thereof through the filter sheet.

A second embodiment of the subject invention utilizes a similar triad configuration of cells of colored phosphor which, when selectively excited, emits light in the basic colors of red, blue or green.

The embodiments of the invention will be explained in greater detail below with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates the triadic arrangement of basic color elements which for color display purposes is also used in television.

FIG. 2 illustrates the formation of the two conductor fields on the limiting planes of the arrangement opposite each other.

FIG. 3 illustrates the triadic arrangement of the basic colors and of the two associated conductor fields with transparent surfaces for observing additional visual information provided behind the arrangement.

FIG. 4 illustrates in schematic form a plasma display panel incorporating the triadic arrangement with associated horizontal and vertical selection and drive control circuitry.

FIG. 5 is a section view taken along the lines 55 of FIG. 4.

FIG. 6 illustrates an isometric view of the filter sheet used in the plasma panel illustrated schematically in FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a prior art arrangement, of a configuration of cells which can be selectively energized to emit light in the basic colors red R, blue B, and green G. In a color television system, each one of these elements can be selectively illuminated when impinged by the cathode ray. By respective superposition of different combinations of the basic colors, the necessary mixed colors can be obtained.

FIG. 2 shows one arrangement of the parallel conductor array on one of the two surfaces defining the depth of the discharge chamber the vertical conductor array being shown in hatched representation. These hatched vertical conductors designating a location on the lower plate of the display, as more fully shown in FIGS. 4 and 5, are divided into groups of three, each conductor being associated with cells representing a primary color R, B, G for the addressable coordinates YI-Y6. By means of these groups of three, one, two, or all three basic color cells can be excited at the individual Y coordinates. Conductors X1, X2 and X3 of the second array which are required for the X- definition of the individual selectively illuminable cells are shown in continuous lines in FIG. 2, since they represent the conductor array associated with the upper or viewing plate. With respect to the second mentioned conductor array, they are arranged substantially orthogonally to the first array and are of meandering shape. The crossover points of the parallel Y conductors with the meandering X conductors are positioned in a triangle to form a triad. The X-conductors are arranged on that inner surface of the discharge space which is opposite to the inner surface with the Y- conductors. With modern technology it is possible without any special difficulty to form the two conductor arrays on the inner surfaces of the associated substrate of a gas discharge device.

By addressing Y-conductor Y3/B and X-conductor X2, for example, a blue light emission can be effected at coordinate X2, Y3. If Y-conductor Y3/R is excited at the same time there is an illumination in the mixed colors of red and blue. In this manner, the corresponding individual or mixed colors can be excited at all coordinates.

Apart from the relatively easy manufacturing process for the two conductor arrays with conventional plasma technology, the substantially vertical position of the two conductor with respect to each other is of particular advantage as compared to the three dimensional addressing of the above referenced US. Pat. No. 3,790,841. It permits conventional addressing with orthogonally arranged coordinates, is known in connection with conventional black and white display. This is also a prerequisite for compatibility between colored and black and white display which with respect to image generation and transmission.

Another highly important feature with respect to the efiiciency of the manufacture of the overall arrangement, compared with known devices for multicolored display with at least two discharge spaces, is the use of a single gas chamber.

In the unique discharge cells provided the primary excitation of polychromatic, e.g. white, light is effected at all coordinates for cells R, B and G. Of that light, only the red, blue or green light portions are to be made visible at the individual light cells. For that purpose, a filter sheet of the type shown in FIG. 6 may be arranged over the entire display portion, said filter sheet having small limited areas designated R, B, G translucent for one of the three basic colors. The filter sheet may be arranged in such a manner that it faces the observer.

When phosphorescent particles are applied to the walls inside the discharge chamber, the distribution of the electric field in each discharge cell can be seriously distorted. If, on the other hand, phosphorescent partizles are applied on the wall outside the discharge cham- Jer, a detrimental ultraviolet absorption in the dis- :harge chamber limiting wall charge could take place. Furthermore, there may be adhesion problems with the Jhosphors, since the phosphorescent particles are nec- :ssarily placed partly on the transparent metal conduc- :ors, and partly on the dielectric surface, so that differ- :nt expansion coefficients are effective for each re- :pective cell. A display device using a filter sheet coactng with a homogeneous light emission from a dis- :harge chamber as shown by the preferred embodinent of the subject invention does not have these distdvantages, and presents as an advantage the eliminaion of the need of using phosphors in various colors iroviding the multi-color image points.

Another advantage is the design of the intersections aetween the X and Y conductors in accordance with IG. 2. Since the firing of individual cells is confined to mall areas, cross talk between adjacent but nonelected cells is eliminated or substantially reduced.

FIG. 3 illustrates a special design of the conductor arrays and of the translucent light filter elements R, B, 3 arranged in the filter sheet. This configuration provides, between the individual light emission cells, transparent areas 30 permitting display of additional visual information arranged behind the triads. However, since these transparent areas do not have conductors associated therewith, such information could be permanently recorded on these areas or projected through a rear projection system. This device of FIG. 3 combines the advantages of a single chamber cooperating with a filter as specified above. By modifying the distances between the X-conductors and/or between the Y- conductor groups the resolution of the panel can be varied.

Referring now to FIG. 4, there is illustrated a gaseous discharge display panel utilizing the techniques of the present invention for a multicolor display. The display is shown as incorporating five horizontal conductors and six sets of vertical conductors. The panel comprises an upper plate or substrate 21 on which a horizontal conductor array comprising conductors Xl-XS is formed, and a lower vertical plate 23 on which six sets of three vertical conductors Yl-Y6 is formed. Since the location of the translucent light filter elements coincides with the location of the light emitting areas, the filter sheet has been omitted from FIG. 5 in the interest of clarity. However, as obvious from FIG. 3 and preceding descriptions, the filter sheet is positioned over the upper surface of substrate 21. The panel is addressed by horizontal selection and drive control circuitry 25, and vertical selection and drive control circuitry 27. Such panels are constructed as fully described in the aforereferenced US. Pat. No. 3,837,734 and driven as fully described in the aforereferenced copending application Ser. No. 372,384. Reference is made to the above related patent and application for a more complete teaching.

Referring now to FIG. 5, there is illustrated a sectional view of the display panel of FIG. 4 taken along the line meandering 5--5 of FIG. 4. The upper and lower substrates 21-23 have conductors formed thereon, conductor X5 being visible on plate 21, conductor sets Yl-Y6 being shown in exaggerated width in the interest of clarity. Again, the filter sheet associated with substrate 21 has been omitted from the drawing in the interest of clarity. The red, blue and green drive lines of Y1 are identified in FIG. 5 as R, B, G. Formed over each of the X and Y conductors arrays is an associated

dielectric layer

27, 29, respectively, which solate the conductors from direct contact with the gas in chamber 35. While not shown in FIG. 5, the surface of the dielectric layer may be refractory or incorporate a layer of refractory material having secondary emission characteristics such as described in copending application Ser. No. 176,626 (IBM Docket Ki9-7l-008) filed by P. H. I-laberland et al. for Improved Dielectric lnsulator for Gaseous Discharge Device", now abandoned. The edges of the panel are sealed by seals 31-33, and the panel might incorporate spacers to maintain a uniform gas layer 35.

FIG. 6 illustrates an isometric view of the filter sheet illustrated schematically in FIG. 3. The filter sheet has the triadic arrangement of red, blue and green filters, with transparent areas 30 covering the remainder of the filter sheet. This sheet is associated with substrate 21 on which the horizontal conductors X, X, are formed, and is therefore on the viewing side of the panel. This arrangement of filter elements in a polychromatic phosphor configuration has been fully described above.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and detail may be made first and second array producing discharge of the associated cell, said discharge producing a light emission corresponding to a selected color.

2. An arrangement as claimed in claim 1 wherein said therein without departing from the spirit and scope of 5 adjacent cells are arranged in 60 triad configuration,

the invention.

What is claimed is:

l. A gas discharge device for a multicolor information display having a gas composition within a discharge chamber which can be excited into illumination by means of ionization, wherein the opposing sides of said discharge chamber include first and second arrays of substantially parallel conductors,

said conductor arrays being disposed at an angle relative to each other,

the crossover points of respective conductors of said first and second arrays defining coordinate discharge cells, the improvement wherein a single discharge chamber is provided for exciting the light emission for all basic colors and combinations thereof,

wherein the conductors of said first array are divided into associated groups of three conductors,

each of said three conductors being suitable for exciting one of three adjacent cells in one of the three basic colors, said second conductor array comprising a plurality of individual parallel conductors connected in a meandering configuration through the cells of associated groups of conductors, the coincident energization of a conductor from said each cell being provided for emitting one of the three basic colors.

3. An arrangement as claimed in claim 1, characterized in that the meandering configuration of said conductors in said second array intersect substantially straight conductors of said first array, the crossover points being defined by orthogonally crossing conductors.

4. An arrangement as claimed in claim 2, characterized in that the cells of each triad configuration are joined to each other without gaps, but individual triad cell configurations are separated by transparent areas for observing additional display data.

5. An arrangement as claimed in claim 4 characterized in that said additional display data is disposed behind the discharge device.

6. An arrangement as claimed in claim 1 wherein all said discharge cells are adapted for the primary emission of polychromatic white light, said arrangement being characterized in providing over the entire display surface a filter sheet with individual areas corresponding to said cell locations which are transparent to one of the three basic col- OI'S.

Claims

1. A gas discharge device for a multicolor information display having a gas composition within a discharge chamber which can be excited into illumination by means of ionization, wherein the opposing sides of said discharge chamber include first and second arrays of substantially parallel conductors, said conductor arrays being disposed at an angle relative to each other, the crossover points of respective conductors of said first and second arrays defining coordinate discharge cells, the improveMent wherein a single discharge chamber is provided for exciting the light emission for all basic colors and combinations thereof, wherein the conductors of said first array are divided into associated groups of three conductors, each of said three conductors being suitable for exciting one of three adjacent cells in one of the three basic colors, said second conductor array comprising a plurality of individual parallel conductors connected in a meandering configuration through the cells of associated groups of conductors, the coincident energization of a conductor from said first and second array producing discharge of the associated cell, said discharge producing a light emission corresponding to a selected color.

2. An arrangement as claimed in claim 1 wherein said adjacent cells are arranged in 60* triad configuration, each cell being provided for emitting one of the three basic colors.

6. An arrangement as claimed in claim 1 wherein all said discharge cells are adapted for the primary emission of polychromatic white light, said arrangement being characterized in providing over the entire display surface a filter sheet with individual areas corresponding to said cell locations which are transparent to one of the three basic colors.