US3654508A

US3654508A - Display panel having a plurality of display registers

Info

Publication number: US3654508A
Application number: US21125A
Authority: US
Inventors: Bernard Caras
Original assignee: Burroughs Corp
Current assignee: Unisys Corp
Priority date: 1970-03-19
Filing date: 1970-03-19
Publication date: 1972-04-04
Anticipated expiration: 1989-04-04
Also published as: CA932782A

Abstract

A display panel includes a plurality of display cells arrayed in rows and columns, with electrodes coupled to the cells in such a way that a plurality of rows of characters can be displayed, with blank spaces being provided between the rows of characters. Electrodes may be provided in these blank spaces to perform an auxiliary function such as a keep-alive function.

Description

United States Patent Caras [4 1 Apr. 4, 1972 5 DISPLAY PANEL HAVING A [56] References Cited [721 Bernard Came Princeton 2,847,615 8/1958 Engelbart 1 5/84.6 Assignee2 Burroughs Corporation Detroit l Engelbart [22] Filed: Mar. 19, 1970 Primary Examiner-John Kominski Assistant Examiner-Palmer C. Demeo [21 1 Appl' Anomey-Kenneth L. Miller and Robert A. Green 52 us. 01. ..313/19s, 313/109.5, 313/220, [57] ABSTRACT 315/84.6, 315/1 TV A display panel includes a plurality of display cells arrayed in [51 Int. Cl. ..H0lj 61/54 rows and columns, with electrodes coupled to the cells in such [58] Field of Search ..3l5/84.6, 169 R, 169 TV; a way that a plurality of rows of characters can be displayed,

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ATTORNEY Patented April 4, 1972 3 Sheets-Sheet 5 S m Q m l M m V d m w a g 6Q I09 mom: Q09 mow? f9 m 0m 1 20m; zow 087 @09 Wow; 7 om mwr mm v9 0% mm? S Q Q Q Q Q Q Q Q Q Q Q Q omT Q Q Q Q Q Q Q Q Q Q Q Q oi 3 Q Q 3 3 3 Q Q Q Q Q \[Owr Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q ATTORNEY DISPLAY PANEL HAVING A PLURALITY F DISPLAY REGISTERS BACKGROUND OF THE INVENTION Display panels of various types including a plurality of display cells arrayed in rows and columns have been known for some time. However, until recently, these devices have not been commercially available.

Display panels are useful because they provide a compact means for displaying information, and use can be made of panels of all sizes from, for example, postage stamp size to wall size. A particularly useful panel is one which can be used to display several rows of information simultaneously. However, at the present time, such a multi-row or multi-register display panel is not known.

SUMMARY OF THE INVENTION Briefly, a display panel embodying the invention comprises a gas-filled envelope and an assembly therein including a plurality of gas-filled cells and a plurality of electrodes which perform different functions. The various electrodes and the associated structural elements are interrelated and arranged to display a plurality of registers of information simultaneously.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a panel embodying the invention and illustrating the capability thereof of displaying several registers of information;

FIG. 2 is a plan view of a portion of a display panel embodying the invention;

FIG. 3 is a perspective view of a portion of a panel embodying the invention showing a portion thereof which is associated with the portion shown in FIG. 2;

FIG. 4 is a sectional view along the lines 44 in FIG. 2 but including all other parts of the panel not shown in FIG. 2;

FIG. 5 is a sectional view along the lines 55 in FIG. 2 but including all other parts of the panel not shown in FIG. 2;

FIG. 6 is a sectional view along the lines 6-6 in FIG. 2 but including all other parts of the panel not shown in FIG. 2;

FIG. 7 is a sectional view along the lines 77 in FIG. 2 but including all other parts of the panel not shown in FIG. 2; and

FIG. 8 is a sectional view along the lines 8-8 in FIG. 2 but including all other parts of the panel not shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A display panel 10 described herein is a thin, flat, sheetlike member which may have substantially any desired size and shape from, for example, postage stamp size to wall size, and it may include substantially any number of display cells. The panel may also include any suitable ionizable gas such as neon, argon, xenon, etc., singly or in combination, with a vapor of a metal such as mercury usually included in the gas to minimize cathode sputtering. The panel, as illustrated in FIG. 1, displays three rows of characters, with each character being made up of a plurality of dots of light generated by gas-filled display cells and with a space being provided between each row of characters. Each row of characters is known as a register. Of course, the number of registers and the number of characters displayed per row may be readily increased in accordance with the principles described herein.

Ordinarily, display devices which use dots of light to form characters utilize a matrix of at least 7 X7 dots to form a character. Such a matrix may also be used in panel 10 in actual practice. However, for purposes of illustration, a smaller number of dots is shown and described.

The display panel 10, embodying the invention, includes a bottom plate of an hermetic, dielectric material, such as glass or ceramic, which has a top surface 30, a bottom surface 40, an upper edge 50, a lower edge 60, a left edge 70, and a right edge 80. The plate 20 has a plurality of parallel slots or channels 90 (A to N) formed in the top surface 30 thereof. For purposes of illustration, the panel is oriented so that the slots extend horizontally across plate 20 from the left edge 70 to the right edge 80.

The array of slots 90 is suitably positioned between the upper and lower edges of plate 20, with the first slot 90A being closest to the upper edge 50 of the plate, and the last slot 90N being closest to the lower edge 60 of the plate.

The slots 90 are all identical in size, shape, width, depth, etc., and can be made by any suitable mass production process. For purposes of illustration, three slots 90 are used in forming a row or register of characters 12, in a manner to be described, and the plate includes three groups of three slots 90 for displaying three rows of characters with, say two, non-display slots 90 between each group of three display slots. The two non-display slots provide spacing between each row of characters.

In panel 10, slots 90A, B, C form one display register; slots 90D and E form non-display, inter-register slots; slots 90F, G, H form the next display register; slots 90] and K form the next non-display, inter-register slots; and slots 90L, M, N form the third display register.

In one embodiment of the invention and for a purpose to be described, the inter-register slots 90D, E, .I, and K are terminated near the left-hand edge of plate 20 by a mass of glass 93 or the like deposited therein. These slots thus terminate near the left edge 70 of the plate 20 and of the panel, this being the end at which a scanning operation originates in one mode of operation of the panel to be described.

Electrodes 110, which are used as counting or scanning anodes in one mode of operation of the panel, are seated in each of the three display slots 90 of each character display register, and these electrodes extend beyond the left and right edges of plate 20 and of the panel 10 so that they are accessible outside the panel. Electrodes 1 10 are preferably individual wires set into the slots; however, they may also be plated, evaporated, or otherwise formed in the slots. The electrodes 110, if separate wires, might also be secured in the slots 90 by means of a cement such as a fused glass frit or the like. In one embodiment of the invention, an auxiliary wire electrode 120, if needed for a purpose to be described, is seated in each of the inter-register slots 90D, E, .I, and K, and these originate at the obstruction 93 and extend leftward beyond the left end 70 of the plate 20.

Panel 10 also includes a center sheet or plate of a dielectric material, the same as the material of plate 20 if desired, which is seated on bottom plate 20 and has a top surface 132, a bottom surface 134, an upper edge 136, a lower edge 138, a left edge 140, and a right edge 142. The sheet 130 is provided with a plurality of rows and columns of apertures or holes 144, and the bottom surface 134 thereof is provided with a plurality of generally rectangular, parallel, vertical slots 150A to P. Slots 150 all have the same width and depth and extend along sheet 130 from the lower edge 138 to the upper edge 136. The slots 150 are oriented at 90 to each of the slots 90, and thus, in effect, cross each of the slots 90 in the bottom plate 20. The array of slots 150 is suitably positioned between the left and

right edges

140 and 142, respectively, of center sheet 130, with the first slot A (FIG. 3) considered to be the first slot positioned near the left edge 140 of sheet 130, and the last slot 150P being positioned close to the right edge 142 of sheet 130.

In plate 130, the holes 144 are arrayed in rows and columns, with the columns of holes aligned with and overlying each of slots 150C to 150P but not slots 150A and B. The rows of holes 144 are generally aligned with and overlie all of the slots 90. The holes 144 are all identical, and the slots 150 are all identical, and each may be made by any suitable mass production process. Holes 144 are not required over the inter-register, non-display slots 90. However, in mass production manufacture of the plate 130, it is as easy to provide them as not.

A plurality of electrodes A to N, operated as scanning cathodes, are seated in the slots 150C to P, respectively, in sheet 130. The scanning cathode electrodes 160 are metal strips which substantially fill the slots 150 and extend along the entire length thereof and beyond the upper and lower edges of plate 130. The cathodes 160 are oriented at 90 to the anodes 110, and each cathode crosses each anode. Each electrode 160 is provided with a plurality of tiny apertures 162 disposed along its length, with each aperture 162 being generally centrally positioned over a slot 90 (FIG. 4) in bottom plate and beneath a hole 144 in center plate 130. Each column of cathode apertures 162 is aligned with a column of holes 144, and the rows of apertures 162 formed by the adjacent cathodes are aligned with the rows of holes 144. Apertures 162 are not required over inter-register slots 90. The cathodes 160 are identical in size and shape and can be made by any suitable mass production process.

An unapertured cathode strip electrode 161, which is somewhat narrower than the cathodes 160 and the slots 150, is seated in slot 1508, and a strip electrode 163 which is identical to cathodes 160, but does not have apertures, is seated in slot 150A. The cathode electrodes 160 and

electrodes

161 and 163 need not be seated in slots in plate 130, if desired.

A second group of wire electrodes 180, used as display anodes, are seated on or in the top surface 132 of plate 130, one for each wire electrode 110 in plate 90. Each electrode 180 is parallel to and aligned with an electrode 110. Each electrode 180 is generally aligned with and overlays a row of holes 144 in center sheet 130. The electrodes 180 need not be centered over the holes; they need only communicate with the gas in the holes. Thus positioned, electrodes 180 are parallel to and are aligned with wire electrodes 110 in plate 20.

A transparent cover or viewing plate 190 of a dielectric material such as glass completes the panel and is seated on center plate 130. The wire electrodes 180 might be seated in slots in the bottom surface of top plate 190, as shown in FIGS. 6 to 8, if desired. In the completed panel 10, the three

plates

20, 130, and 190 are hermetically secured together by a seal 200 formed along their adjacent edges by any suitable means such as a fused glass frit (Pyroceram) or the like.

The gas used in panel 10 is introduced in any suitable manner, for example, by means ofa bell jar or by means of a tabulation 203 (shown only in FIG. 4), secured to bottom plate 20.

As described, panel 10 includes, in each register, a lower layer of gas cells 210 which are called counting or scanning cells (FIGS. 2, 4, and 8) arrayed in rows and columns, with each cell comprising a portion of the apertured strip cathode electrode 160 above it, the anode electrode 110 below it and the gas volume between these electrodes in slot 90. Thus, each column of counting cells is defined by each cathode 160 and its crossing of a slot 90 and the associated portion of a counting anode 110. As seen in FIG. 2, there are 12 columns of counting or scanning cells 210, and, for purposes of description, the first column is associated with cathode 160A, the second column with cathode 160B, the third column with cathode 160C, etc. Each column of scanning cells 210 communicates with the adjacent column, that is, each scanning cell in one column communicates with the corresponding cell in the adjacent column, through the associated slot 90.

The panel 10 also includes an upper layer of gas cells 220, known as display cells, associated with and positioned above and generally aligned with, the counting cells 210. Each display cell 220 (FIGS. 4, 5, and 8) is made up of a portion of a cathode 160, the associated gas-filled hole or cell 144 in center sheet 130, and the associated portion of upper anode electrode 180. As with the counting cells, there are also 12 columns of display cells 220, each associated with a cathode 160, with the first column associated with cathode 160A, etc.

The panel 10 also includes a column of auxiliary cells 224, which are known variously as starter cells, reset cells, particlesupply cells, or glow-spreading cells (FIGS. 2 and 7), and these cells supply excited particles to facilitate the turn-on of the first column of counting cells 210 associated with cathode 160A at the beginning of a scanning cycle, to be described.

For convenience, cells 224 will be called reset cells. These reset cells are arrayed in a column to the left of the first column of counting cells and communicating therewith through slots A, B, C, and F, G, H, and L, M, N. Cells 224 are constituted by the cathode strip 161 and the portion of each anode which it crosses and the gas volume in the slots 90 therebetween.

Generally, in operation of a display panel such as panel 10, particularly in a scanning type of operation (see commonly assigned patent application Ser. No. 850,984, filed Aug. 19, 1969) wherein the columns of scanning cells are fired in turn and in series beginning at the left end of the panel and proceeding to the right end thereof, it is customary to provide the reset cells 224 to facilitate the turn-on of the first column of scanning cells which are associated with display cells. Other arrangements are known for providing and operating such reset cells (see commonly assigned patent application Ser. No. 881,024, filed Dec. 1, 1969). In addition, it may be desirable to provide auxiliary cells, known as keep-alive cells, for operation of the reset cells. Various arrangements are known for providing keep-alive cells, and one of these is described and claimed in applicant's copending and commonly assigned application Ser. No. 6,839, filed Jan. 29, 1970.

In another suitable arrangement, referring to panel 10, the electrodes in the inter-register slots 90 and the first electrode 163 may be used to provide a keep-alive function. The keep-alive cells 228 formed by these electrodes communicate with the reset cells through spaces around the masses 93 and thereby provide excited particles to facilitate the operation of the reset cells.

Generally, a keep-alive function is achieved by having the keep-alive cells always ON and fired to maintain a constant supply of excited particles for the reset cells. In this type of operation, electrode 163 may be operated as a cathode, and electrodes 120 as anodes, or vice versa.

In the description of the operation of the invention set forth below, reference is made to scanning or glow transfer" from cell to cell or column to column. Several different types of actions occur including glow transfer from the keep-alive cells 228 to the reset cells 224, from the reset cells 224 to the scanning or counting cells 210, from a scanning cell to a scanning cell, and from a scanning cell to a display cell 220. The exact mechanism by which each such operation occurs cannot be described with complete certainty; however, the operations may involve actual transfer of a mass of glowing ionized gas, or the diffusion of excited particles including metastable states which facilitate a new firing of an OFF cell, or both mechanisms may be involved.

In operation of the panel 10, the keep-alive cells 228 communicate, by means of the diffusion of excited particles, with the reset cells 224 through slots 90D and E and slots 90J and K. Excited particles also diffuse along keep-alive cathode 163 and in the spaces between this cathode and its slot A and reach reset cathode 161 by way of others of the slots 90. As noted, the keep-alive cells are always ON, and, when it is desired to turn on the reset cells 224, operating potential is ap plied to the reset cathode 161 and to all of the anodes 110. With the aid of excited particles from the keep-alive cells, glow spreads along the entire length of the reset cathode 161 in the spaces (FIG. 4) on either side thereof.

When the reset cells 224 have fired, the first column of counting cells 210 can be fired with the aid of excited particles generated in the reset cells and able to diffuse to the first column of counting cells through slots 90A, B, C and 90F, G, H and 90L, M, N. An arrangement for using reset cells to fire counting cells is described and claimed in copending and commonly assigned application Ser. No. 791,208 filed Jan. 7, 1969. In addition, methods and apparatus including circuits for scanning columns of counting cells and energizing display cells therefrom are described and claimed in the above-mentioned application Ser. No. 850,984. These circuits are not shown here. In a typical scanning operation, the scanning or counting anodes 110 are connected to driver circuits for applying generally positive operating potential thereto, and each of the cathodes 160 is connected to a driver circuit for applying generally negative operating potential to each, sequentially, to cause each column of counting cells 120 to fire and glow. The firing of each column of counting cells, after the first has been fired, is facilitated by the diffusion of excited particles through the slots 90 from ON counting cells to the adjacent OFF counting cells to be fired. The columns of counting cells 210 are fired sequentially from left to right, as seen in FIG. 2. This sequential firing of the columns of lower counting cells 210 is carried out cyclically from left to right. Each time the last column of counting cells at the right-hand edge of the panel is reached, the column of reset cells 224 at the left-hand edge of the panel is turned on again, with the aid of the keep-alive cells, and the above-described cycle is repeated. If desired, circuit means may be provided to sense the turn-on of the last column of counting cells 120 and automatically turn on the reset cells to start the cycle again.

When it is desired to fire cells 220 in the upper layer to provide a display of information or the like, generally positive operating potentials are applied to the proper upper anodes 180 associated with the cells 220 to be fired and glow transfers from the associated lower cells 210 through the apertures 162 in cathode electrodes 160 to the upper cells where the glow can be viewed through top plate 190. As described above, the glow transfer is facilitated by the presence of excited particles in each of the lower counting cells 210 when it is fired. By properly synchronizing the switching of the cathodes with the application of information signals to the display anodes 180, the desired characters are displayed in each register.

It is clear that modifications may be made in the panels described within the scope of the invention. For example, although the panel as described is scanned from left to right, the scanning may be effected in other ways, and this might require a rearrangement of parts. In addition, in some modes of operation, keep-alive cells may not be required, and, in some cases, both keep-alive cells and reset cells may not be needed.

In general, the drawings are not intended to be dimensionally exact, and, in a typical display panel embodying the invention, the top plate 190 and bottom plate are about one-fourth inch in thickness, and the center plate 130 is about 40 mils in thickness. In addition, in plate 20, slots 90 are 10 mils wide and mils deep, and

electrodes

110 and 120 are 5 mils in diameter. ln plate 130, slots 150 are 36 mils wide and 1 to 3 mils deep, with

cathodes

163 and 160 having approximately the same dimensions. The holes 162 in the cathodes 160 are l to 3 mils in diameter, the holes 144 in plate 130 are 18 to 24 mils in diameter and mils deep, and electrodes 180 are about 3 mils in diameter.

What is claimed is:

l. A display panel comprising a gas-filled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material and hermetically sealed together along their adjacent edges, said bottom plate having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge,

said bottom plate also having a plurality of first parallel identical slots extending into said plate from said top surface and extending along the entire length of said plate,

first electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of first slots comprising display registers,

each of said several groups of said first slots being separated by an inter-register slot which does not contain one of said first electrodes in it,

said center plate having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge,

a plurality of second electrodes disposed between said bottom plate and said center plate and oriented at an angle to said first electrodes, each second electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes at the crossing,

a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said second electrodes, and

a plurality of third electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each third electrode also being aligned with one of said first electrodes.

2. The panel defined in claim 1 wherein an auxiliary electrode is seated in said inter-register slot.

3. The panel defined in claim 1 wherein said inter-register slot is blocked by an insulating mass and an auxiliary electrode is seated therein.

4. A display panel comprising a gasfilled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material and hermetically sealed together along their adjacent edges,

said bottom plate having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge,

first anode electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of slots being associated with display registers,

each of said several groups of said first slots being separated by an inter-register slot which does not contain one of said first electrodes,

said center plate of dielectric material having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge,

a plurality of electrodes comprising cathodes disposed between said bottom plate and said center plate and oriented at to said first electrodes, each cathode electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes at the cell crossing,

a first auxiliary cathode electrode adjacent to the first cathode in said array of cathode electrodes,

auxiliary electrode means adjacent to said first auxiliary electrode and adapted to be held ON to provide a constant source of excited particles for said first auxiliary electrode,

a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said plurality of cathode electrodes, and

a plurality of second anode electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each second electrode also being aligned with one of said first anode electrodes.

5. The panel defined in claim 4 wherein each of said plurality of cathode electrodes comprises a metal strip which has a series of apertures extending along its length, each said aperture communicating with a hole in said center plate.

6. The panel defined in claim 4 wherein another electrode is seated in said inter-register slot.

7. The panel defined in claim 4 wherein said inter-register slot is blocked by an insulating mass and another electrode is seated therein.

Claims

1. A display panel comprising a gas-filled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material and hermetically sealed together along their adjacent edges, said bottom plate having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge, said bottom plate also having a plurality of first parallel identical slots extending into said plate from said top surface and extending along the entire length of said plate, first electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of first slots comprising display registers, each of said several groups of said first slots being separated by an inter-register slot which does not contain one of said first electrodes in it, said center plate having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge, a plurality of second electrodes disposed between said bottom plate and said center plate and oriented at an angle to said first electrodes, each second electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes at the crossing, a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said second electrodes, and a plurality of third electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each third electrode also being aligned with one of said first electrodes.

4. A display panel comprising a gas-filled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material and hermetically sealed together along their adjacent edges, said bottom plate having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge, said bottom plate also having a plurality of first parallel identical slots extending into said plate from said top surface and extending along the entire length of said plate, first anode electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of slots being associated with display registers, each of said several groups of said first slots being separated by an inter-register slot which does not contain one of said first electrodes, said center plate of dielectric material having a top surface, a bottom surface, a left edge, a right edge, an upper edge, and a lower edge, a plurality of electrodes comprising cathodes disposed between said bottom plate and said center plate and oriented at 90* to said first electrodes, each cathode electrode crossing each first electrode, eAch crossing defining a cell which can be fired by potentials applied to the two electrodes at the cell crossing, a first auxiliary cathode electrode adjacent to the first cathode in said array of cathode electrodes, auxiliary electrode means adjacent to said first auxiliary electrode and adapted to be held ON to provide a constant source of excited particles for said first auxiliary electrode, a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said plurality of cathode electrodes, and a plurality of second anode electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each second electrode also being aligned with one of said first anode electrodes.