US2928014A - Electronic device cathode ray tubes - Google Patents

Description

March 8, 1960 W. R. AIKEN ETAL ELECTRONIC DEVICE CATHODE RAY TUBES Filed May 2, 1955 4 Sheets-Sheet 1 INVENToRs WILLIAM n. AIKEN LBSLI@ J- @ook Bu@ A. SHANAFRLT BTTORNY March 8,1960 w. R. AIKEN ETAL ELECTRONIC DEVICE CATHODE RAY TUBES 4 Sheets-Sheet 2 Filed May 2, 1955 f JNVENToRs WILLIAM JR. AIKRN L SLIE I COOK BY )C F5- 51"! ANAFELT March 8, 1960 w. R. AlKl-:N ETAL ELECTRONIC DEVICE cATHonE RAY TUBES 4 Sheets-Sheet 3 Filed May 2, 1955 r/ /////%Zf /A W by@ n@ T m MXR? Y VMOH m mnw a M m Ams. T. MLA a umm w L W .www

March 8, 1960 w. R. A IKEN ETAL ELECTRONIC DEVICE CATHonE RAY TUBES Filed may 2, 1955 4 Sheets-Sheet 4 INVENToRs Smm WILLIAM R BIKEN 5% ATTORNEY United States Patent ELECTRONIC DEVICE CATHODE RAY TUBES William R. Aiken and Leo A. Shanafelt, Los Altos, and

Leslie J. Cook, Lafayette, Calif., assiguors, by mesue assignments, to Kaiser Industries Corporation, a corporation of Nevada Application May 2, 1955, Serial No. 505,202 17 Claims. (Cl. 313-78) The present invention is directed to a new novel cathode ray tube and a method for producing same. More specifically, the invention is concerned with a cathode ray tube known in the art as the Aiken-type tube employing the electrostatic deflection principles set forth in the U.S. Patent No. 2,795,731, which issued to W. R. Aiken on June 11, 1957. p

The Aiken-type tube, in its basic concepts, is comprised of a configuration which approximates that of a picture adapted for wall mounting. In a smaller size the tube is comparable in size and shape to a metropolitan telephone directory.

The novel Aiken-type tube in its most basic form cornprises an electron gun and a primary section including a set of horizontal deflection electrodes, a transition Section including a focusing and an accelerating electrode, and a high voltage section including a target and a set of vertical deflection plates spaced therefrom.

An electron beam is delivered by the gun into the primary section along a path vwhich lies adjacent the horizontal deflection plates, By application of signal voltages to the deflection plates, the beam is bent vertically at any desired plate and through the transition section into the field-free region between the transparent deflection plates and the electrically charged phosphor target; Deflection of the beam into the target at any desired vertical level is achieved by applying voltages to a corresponding one of the vertical deflection plates. Thus the position of the spot created by the deflected beam may be controlled as desired.

The numerous advantages and applications of the socalled flat tube are well known to persons skilled in the art. Prominent among the features and advantages attendant of this general type are its overall compactness which permits the use thereof in smaller areas; extremely high definition and resolution which results from the inherently sharp electrostatic focus arrangement; the reduction in expensive components resulting from the use of only electrostatic deflection elements and the elimina tion of yhigh voltage deflection yokes, vertical and horizontal output transformers, magnetic deflection coils, and othersr of the bulky and expensive components now incidental to the vertical and horizontal stages for use with cathode ray tubes now known in the art. The novel tube of the` instant invention also features the reduction in weightof its physical mass, and the minimization and simplification of adjustment of the tube for use in the desired applications; flexibility in adaptation to mounting in various positions and in association with other equipment, and adaptability for use with other types of electronic and optical units. These, and other features and advantages, have been set forth only briefly herein, and numerous other features and advantages will doubtless be apparent .to parties skilled in the art.

In the embodiments of the Aiken tube disclosed in :the aforementioned applications the electrodes which form the deflection and focusing electrodes of the primary and transition sections were made of separate metal elec- ICC trodes which were mounted on insulating frames. The high voltage section was formed of individual members of nonconducting glass having coatings thereon. The high voltage section, transition section and primary structure were supported within an evacuated envelope.

In the present invention all internal structures with the exception of the electron gun are formed by applying conductive films to appropriately contoured surfaces of the vacuum envelope. That is, two molded panels are formed to provide internal surfaces pressed thereon which geometrically conform with the surfaces of the deflection and focusing electrodes of the primary and transition sections utilized in the above described prior art embodiments. The primary and transition sections comprise discrete conductive coatings applied to the inner contoured surfaces of the panel walls to provide focusing, accelerating and deflection electrodes thereon, and the high voltage section comprises a series of deflection plates coated on the inner surface of one panel and a fluorescent target material coated on the inner surface of the mating panel. Thus the entire tube consists of two glass panels having coated control sections on the interior surface thereof and electron gun. Such arrangement obviously offers substantial manufacturing economies and a tube of extreme ruggedness and reliability.

It will be manifest that electron beam source means may be utilized with the tube in a number of various manners. The beam source means, which may be an electron gun of the conventional design with or without electrostatic focus, can for example, be-disposed so as to initially deliver a beam of electrons along a path in substantial alignment with the primary deflection electrodes, or the beam source means may be disposed adjacent a vertical edge of the tube envelope and sealed within the envelope so as to deliver a beam of electrons along a path which is initially perpendicular to an array of primary deflection electrodes. In the latter method of beam source disposition, the gun would preferably be 'completely housed within the unit and the electron beam would be initially bent by employing a ninety degree electron lens mirror to direct the beam into the primary section and to travel a path which is in substantial alignment with the primary deflection electrodes. Other arrangements will be obvious with reference to the aforeidentified applications.

There is also set forth herein an inexpensive, novel and practical method of producing a cathode ray tube, and particularly a novel method of producing a cathode ray tube having an integral electrode arrangement with makes possible subjection of the tube to shock vibration loads of greatly increased magnitudes and the provision of an extremely thin tube structure.

The invention will now be described in detail with reference to the following drawings, in which:

Figure l is a perspective view of the cathode ray tube of the instant invention,

Figure 2 is a sectional view of the tube taken along line 2 2 of Figure l,

Figure 3 is an exploded view of the tube which clearly illustrates the internal structure of the glass panels,

Figure 4 is an end view of an embodiment of thetube partially broken away,

Figure 5 is an exploded view of the tube, and

Figure 6 is a front view of the tube partially broken away showing an embodiment of the invention wherein the electron gun is disposed so as to initially deliver a beam of electrons along a path which is substantially normal to the longitudinal axis of the horizontal deflection electrode structure.

Referring now to a description of the embodiment illustrated in Figures l, 2, and 3, Figure 1 is a perspective View of the cathode ray tube of the invention in its aS- sembled unitary form. It will be noted that the tube envelope is comprised of two mating glass panels and 11 which when sealed together form the composite attractive unitary tube. The panel 10 is adapted to carry a fluorescent coating which is fixedly positioned in laminated relation with the upper inner surface thereof which will be shown and fully described hereinafter with particular reference to Figure 3. Also, the panel 10 is formed with suitable inner geometry to carry conductive coatings along the bottom inner surface portion in fixedly positioned and laminated relation therewith.

The panel 11 is adapted to carry a plurality of optically transparent deflection elements 14 which are fixedly positioned in laminated relation with the upper portion of the inner surface. These deflection elements 14 are formed by painting or otherwise coating on the inner surface of the panel 11 an electrically conducting material which is optically transparent.

It has been found advantageous to apply a coating of stannic chloride between the adjacent vertical deflection electrodes 14 to provide an insulating medium therebetween as well as to provide a leakage path for any charge which migh accumulate on the tube wall between these electrodes 14. Materials such as stannic chloride are suitable for such application in that the material is optically transparent and by proper treatment as set forth in the copending application having Serial No. 521,201 which was filed on July 11, 1955 by W. R. Aiken and assigned to the assignee of this invention, now Patent No. 2,864,970, exhibits high resistance to the conduction of electrical energy.

The lower portion of the panel 11 is provided with laterally extending longitudinal grooves and projections which correspond and mate with grooves and projections formed in the lower portion of the panel 10. It will be noted that the panels 10 and 11 are formed so as to receive an electron gun assembly 12 at the one corner of the unitary envelope, the lower left-hand corner being illustrated in the present disclosure.

The unitary envelope is made of the two- mating panels 10 and 11 joined together with sintering a low-tempera ture glass frit during the final processing of the tube, In order to reduce or minimize the molding expenses, the envelope is so designed that the two panels 10 and 11 are molded from identical molds. When the two panels 10 and 11 are sealed together, the corresponding grooves and projections in the lower portions of the panels mate, and as coated, form the primary and transition sections of the tube.

Figure 2 is a sectional view of the tube of Figure l taken along line 2 2 showing the cross-sectional con` figuration of the tube envelope and the relative disposition of the fluorescent target, and the deflection, acceleration and focusing electrodes. The high voltage section of the tube comprises the fluorescent coating 13 which is applied to the inner surface of the glass panel 10 and the vertical deflection elements 14 which are applied to the inner surface of the glass panel 11. The fluorescent coating 13 is composed of a material, such as phosphor, which will exhibit luminescence upon being excited by an impinging beam of electrons. Such coating may be transparent, if desired. The coating 13 is maintained at the desired potential by a power supply situated outside of the tube envelope and connected thereto through suitable electrical conductors 13a. The vertical deflection elements may be energized as desired by signals extended over conductors 14a to the individual ones of the vertical deflection electrodes. Voltage generator equipment for energizing the electrodes in this manner is set forth in the above mentioned copending applications and in copending application Serial No. 659,677 which was filed May 16, 1957.

The lower portion of the glass panels 10 and 11 are produced with a plurality of grooves and ridges which are co-extensive with the inner surface of the panels and provide the surfaces on which the electrically conducting material is coated. These coating comprise the electrode structures of the primary section.

As shown in the sectional view of Figure 2, the primary section comprises an array of horizontal deflection. electrodes 20, each of which is generally U-shaped in cross-section. The array extends the entire length of the panels as is clearly apparent in Figure 3. The electrodes 20 are spaced from one another by an uncoated area, and as shown in Figure 3 one half of each electrode is painted on the left hand panel 10 and the other half of each electrode is painted in mating relation on the right hand panel 11. Each of the electrodes 20 are energized over suitable electrical conductors 20a by an electric generator such as shown in the above identified copending application, which resides outside the tube wall.

The transition section is also accomplished by the coating of cooperating geometric configurations on the inner surfaces of the glass panels. That is, the glass panels 10 and 11 are provided with inwardly extending projections 21 and 22 respectively, the adjacent surfaces of which are spaced further apart along the top portion than along the bottom portion to provide a divergent aperture for the beam as it passes therethrough. A conducting strip 23 is applied at the bottom and inclined surfaces of the ridge 21 and a conducting strip 24 is applied to the similar portion of the ridge 22. The conducting strips 23 and 24 are substantially coextensive with the length of the panels and are also, as in the case of electrodes 20, energized from a power supply disposed outside of the tube wall through suitable electrical conductors 23a and 24a. The coatings 23 and 24 are to be operated at the same potential and together form an electrode assembly hereinafter referred to as a slotted accelerating electrode which is substantially coextensive with the length of the glass panels.

A conductive coating 27 is applied to the inner surface of glass panel 10 to provide the indicated strip which is suitably energized from a source of potential outside of the tube wall through electrical conductor 27a. A similar coating 28 is applied to the inner surface of the glass panel 11 and disposed in a like position relative to the conducting strip or electrode 27 and is energized over conductor 28a. The conducting strips or electrodes 27 and 28 constitute an electrode pair referred to as a first focusing electrode. These strips are formed to be substantially coextensive with the length of the inner surface of the glass panels 10 and 11 respectively.

T-wo additional conducting strips 31 and 32 are applied to the inner surfaces of the glass panels 10 and 11, respectively, to provide the second focusing electrode, and are coextensive in length with the conducting strips 27 and 28. The panels 10 and 11 are formed with inwardly extending portions 29 and 30 respectively and are so formed as to achieve the desired spaced relationship between the electrically conducting strips 31 and 32. It will be noted that the conducting strips or the electrodes 31 and 32 are spaced apart a lesser amount that the electrodes 27 and 28 and that these strips or electrodes 31 and 32 are also energized from a source of potential situated outside of the tube wall through suitable electrical conductors 31a and 32a.

It will be discerned that each of the aforementioned electrodes is disposed in such a manner that each is suitably spaced from its next adjacent electrode in an amount suflicient to be insulated therefrom. If necessary, a desired non-conducting material, such as for example a chrome oxide solution, properly treated so as to become non-conductive, can be utilized to militate against any conditions effecting shorting or arcing which might occur between adjacent electrodes. Also, a coating material having high electrical resistance characteristics, such as for example properly treated stannic chloride could be applied between the adjacent electrodes to provide a leakage path thereby militating against any undesired charge spasms cumulation which might otherwise occur on the untreated glass of the panels.

The glass panels and 11 are fabricated in such a manner that the primary section, including the horizontal dellection electrodes 20, the electrodes 23 and 24, and the focusing electrodes 27, 28; 31 and 32; is slightly offset relative to the high -voltage or display section. The purpose of this olset relation is such that the electron beam which is deflected, accelerated, and focused within the primary section may be caused to travel along a path which is more closely adjacent the vertical deflection electrodes 14 of the high voltage section than the target. The approximate path of the electron beam is diagrammatically shown in Figure 2.

The display area or high voltage portion of the tube may be designed to be flat with a thickness of 1/z inch. This thickness effects a rigid construction and enables the tube to withstand the dellectionof the glass panels under vacuum loading. The peripheral marginal portions of the mating glass panels are turned inwardly. Manifestly, with the utilization of the 1/z inch thick glass and integral inwardly turned edge portions, the deflection of the glass panels 10 and 11 under vacuum loading produces a load on the frit seal 8 which is almost entirely compressive.

It has also been found that satisfactory results may be obtained in the instant invention by forming, where appropos, at least some of the conducting strips on the surfaces of the tube of tin oxide films.

In order to achieve the proper boundary conditions required to obtain a picture extending all the way to the marginal edge of the fluorescent target 13, the side-wall sections are coated with an electrically conducting material 33 such as a suspension of chromium-oxide (CrO3) and silicic acid (H4Si04). This coating 33 is maintained at the desired potential from a power supply situated outside of the tube wall through a suitable electrical conductor. Further, the coating 33 provides a semiconducting path which maintains the required electric field throughout the display area.

All the electrical leads or conductors are introduced through side wall portions of the tube in close proximity to those electrodes which are intended to be energized. The leads for the high voltage deflection plates 14 are introduced along the inwardly turned edge portion of the panels as is clearly illustrated with reference to Figure 3. Such arrangements is a definite factor in accomplishing the reduction of shielding requirements required inside of the envelope. The electrical connections are introduced through suitable conductors fused through the side wall of one of the glass panels, for example panel 10, as illustrated in Figure 3. It is noted that the size of the primary and transition sections relative to the high voltage section have been enlarged substantially in the drawings (and especially in Figures 4-6) for the purpose of effecting a more clear disclosure of these sections.

It is to be understood that the operation of the instant invention is substantially identical with the operation of the cathode ray tubes set forth and described in detail in the aforeidentified Patent No. 2,795,731. The invention herein set forth is directed to an improvement of the structure of the cathode ray tubes disclosed and claimed in the above applications, and also is directed to a novel method of fabricating the same. However, it is deemed timely to briefly describe the operational characteristics of the tube for purposes of a more complete description herein.

In operation, the electron gun`12, upon suitable energization from an incoming video signal (in television use), causes an electron beam 15 to be delivered along a path which is in substantial parallel alignment with the longitudinal axis of the linear array of horizontal defiection plates 20. Initially, all the horizontal deflection plates are maintained at some potential negative with respect to the cathode potential of the electron gun 12.

As the electron beam 15 enters the region dened by the electrostatic field established by the horizontal deflection electrodes 20, most adjacent to the source of electrons, the repelling force of said field causes the beam to be deflected upwardly in a direction away from the first electrode of horizontal deflection electrodes 20. The equal potential lines established within the horizontal deflection electrodes 20 deflect the electrons through the open side of the electrodes 20 and the slotted accelerating electrode assembly comprised of electrodes 23 and 24.

In the initial condition in which the horizontal dellection electrodes 20 are maintained negative with respect to the beam, it has been found that satisfactory results were obtained by applying a potential of 800 volts negative with respect to the cathode potential of the electron gun. The slotted accelerating electrode assembly is likewise maintained at 800 volts potential positive with respect to the cathode potential of the electron gun.

In achieving a line scan, signals are applied to the horizontal deflection plates 20 in succession, the signals as applied to adjacent electrodes being preferably effected in an overlapping manner. That is, a signal is applied to the deflection electrode closest to the course of electrons which drives the electrode in a positive direction appreaching the value of potential on the slotted electrode assembly. However, prior to the instant the potential value on the first plate reaches a value substantially equal to the potential of the slotted electrode assembly, a positive going signal is applied to the next adjacent plate. Manifestly, when the potential on the first plate reaches the approximate value potential on the slotted accelerating electrode assembly, a field-free zone is established within the region defined by the slotted electrode and the horizontal deflection pla-te and the electron beam is free to travel to the next adjacent horizontal deflection plate. This procedure is repeated along the entire array of plates in such a manner that the charge on at least two plates is always changing at the same tlme.

Further, it is to be understood that the order in which the horizontal deflection electrodes 20 are charged or discharged may be reversed. In such case, initially all the electrodes 20 of the horizontal deflection array are maintained positive with respect to the cathode potential of the electron gun -12. The potential value in such case is equal to the potential value impressed on the slotted accelerating electrode assembly, thereby establishing a field-free zone along the entire longitudinal dimension of the array of horizontal deflection electrodes 20. The field-free zone permits the electrons which comprise the electron beam 15 to travel the entire length thereof. In operation, the horizontal deflection electrode 20 most distant from the electron gun 12 is driven negative. As soon as this electrode is driven toward its maximum value, a negative Igoing signal is applied to the next ad jacent electrode and this procedure repeats successively along the entire array of horizontal deflection electrodes.

In either arrangement, after the electron beam has been deflected by the horizontal deflection electrodes 20, the ybeam 15 is caused to be passed through the slotted accelerating electrode assembly comprised of the electrodes 23 and 24 and accelerated thereby toward the high voltage section. The beam 15 is next caused to pass through two pairs of focusing electrode structures, the first of which is comprised of electrodes 27 and 28, which in a satisfactorily operated embodiment, was maintained. at 2 kv. potential negative with respect to the cathode potential of the electron gun 12. The second focusing electrode assembly comprised of electrodes 31 and 32, 1s maintained within the range of from 0 to 8 kv. poten-- tial negative with respect to the cathode potential of the electron gun 12. These focusing electrodes establish elec.A trostatic fields which tend to focus the electron beam in,`

display section of the tube.'

The electron beam 15, after being deflected, accelerated, and focused in the primary section, is caused to travel along a path in close proximity to the optically transparent vertical deflection electrodes 14. The vertical deflection system is operated much in the same manner in which the horizontal deflection system is operated. The signals applied to the vertical deflection electrodes 14 are also preferably applied in an overlapping manner so that the potential on at least two adjacent electrodes 14 is changing at the same time. Initially, these vertical deflection electrodes 14 and the fluorescent target 13 are maintained at substantially 13 kv. potential positive with respect to the cathode potential of the electron gun 12. By virtue of the fact that each of the elements of the high voltage section is maintained at an equal potential value, a field-free region is established therewithin permitting the electron beam 15 to travel unobstructively within the field-free region until a suitable negative potential is applied to one of the vertical deflection plates 14.

As one electrode 14 is driven negative with respect to the cathode potential of the electron gun 12, the so driven electrode 14 exerts a deecting force on the beam 15 causing it to be deflected toward and impinge on the fluorescent target 13. The electron impingement upon the fluorescent material of the target 13 causes the material to become excited and thereby give off luminescence of an intensity which is directly proportional to the intensity of the impinging electron beam 15. Manifestly, the light emitted from the fluorescent coating may be viewed through the optically transparent dellection electrodes 14 and also may be viewed from a position toward the opposite side of the target 13. In some cases it may be desirable to employ vertical deflection electrodes 14 which are formed of an electrical conductor, such as copper or the like, in which case the image or display presented on the target 13 may be viewed from only a single side.

It is apparent from the foregoing discussion that the position of the beam impingement on the target 13 at any given instant will be consistent with the particular ones of the horizontal and vertical deflection electrodes 20 and 14, which are energized at such instant, and the value of the energizing signal applied thereto.

Thus in the use of the novel tube with a conventional television receiver, the horizontal deflection plates will be cyclically energized at a time rate which is consistent with the provision of the line scan of a television picture, and the vertical deflection plates will be energized at a time rate which is consistent with the provision of a frame scan of a television picture. The energizaton of the vertical and horizontal deflection plates may be effected by suitable electronic generator means which are synchronized in their operation by the incoming sync signal received from the television transmitting station.

The incoming video signal is applied to gun 12 in the conventional manner to effect the reproduction of the transmitted video picture by the beam in its trace over the target.

Various forms of electronic generators suitable for use therewith have been set forth in the copending applications having Serial No. 355,965 and Serial No. 396,120. The novel tube can, of course, be used in any of the known cathode ray tube applications, the nature of the associated circuitry for use therewith varying with the nature of its application in a manner known in the art.

In another embodiment of the invention shown in Figures 4 and 5, the tube is comprised of two mating glass panels 40 and 41. An electron gun 42 is adapted to be disposed at the lower right hand portion of the assembled panels 40 and 41 within an aperture formed therein. The horizontal deflection system comprises a plurality of electrodes 43 which are formed by coating appropriate portions of the lower inner surface of the panels with an electrically conductive material such as, for example, ytin oxide. The electrically conducting coatings applied to the glass panels 40 and 41 are so disposed that when the two mating panels are sealed together the coatings are urged together in such a manner as to form a plurality of electrode structures 43. These individual deflection electrodes 43 are electrically separated from one another by untreated portions of the glass panels or by applying coating of a non-conducting material such as, for example, chrome oxide, between the individual electrodes 43. Each one of the deflection electrodes 43 of the horizontal dellection system is electrically connected to an electrical generator situated outside of the tube wall through individual electrical conductors 43a.

The glass panels 40 and 41 are formed with integral inwardly extending ridges 45 and 46 respectively. Electrically conductive coatings 47 and 48 are applied to the bottom and inclined surfaces of each of the ridge portions 45 and 46. Suitable electrical conductors 47a and 48a are provided to supply the desired voltage to each of these coatings 47 and 48 from a source of potential outside of the tube wall. The conductive coatings or films 47 and 48 constitute an electrode assembly referred to as the slotted accelerating electrode.

Disposed in spaced relation above the slotted accelerating electrode, there is a pair of electrically conductive coatings 51 and 52 applied to the respective inner surface of each of the glass panels 40 and 41, respectively. These coatings are adapted to be energized from a source of potential outside of the tube wall through suitable electrical conductors 51a and 52a, and together thc coatings 51 and 52 form a focusing electrode assembly.

In a like fashion, conductive coatings 53 and 54 are applied to the inner surface of the glass panels 40 and 41 respectively in spaced relationship above the electrodes 51 and 52. The electrodes 53 and 54 are energized from a source of potential outside the tube wall through suitable electrical conductors 53a and 54a. These electrodes 53 and 54 form an additional focusing electrode assembly and are spaced apart from one another a distance which is somewhat less than the spacing between the rst pair of focusing electrodes 51 and 52.

In the present embodiment, the glass panel 41 is formed with a ledge portion 55 which is substantially perpendicular to the outer face of the panel. The ledge portion 55 is adapted to carry an electrode 56 which is formed of an electrically conductive coating and a suitable electrical conductor 56a (Figure 5) extends energizing potential thereto from a source outside the tube wall.

The display area or high voltage section of the tube comprises a coating of fluorescent material 57 on the inner surface of the panel 41 and is maintained at the desired potential positive with respect to the cathode potential of the electron gun 42 by a power supply located outside the tube wall through a suitable electrical conductor 57a.

The vertical deflection elements 58 of the high voltage section of the tube are disposed on the inner surface of the glass panel 40. The elements or electrodes 58 are preferably formed of an electrically conducting optically transparent material thereby making it possible to view the display presented on the target from either side of the unitary tube. However, the vertical deflection electrodes 58 can be formed of an electrically conducting material which is opaque, in which case the display presented by the fluorescent target area may bc viewed from only a single side of the tube.

It has been found advantageous to apply a coating of material having high resistance properties such as a stannic chloride solution, between the adjacent vertical deflection electrodes. This coating provides an insulating medium between the individual electrodes 58 and also provides a leakage path for any charge which might acumuiate thereon and would otherwise tend to establish spurious electrostatic fields. Each of the vertical deflection electrodes 58 isvenergized over suitable electrical conductors 58a which extend to a suitable electric generator situated outside the tube wall.

I The operation of the cathode ray tube illustrated in Figures 4 and 5 is identical with the operation of the embodiment of the tube shown and described in connection with Figures l, 2 and 3. Briefly, the energization of the electrodes 'of the tube may be effected in the several manners set forth in the description of the rst embodiment. In the embodiment of Figures 4 and 5 an additional electrode 56 is employed to effect a sharper bend of the electron beam 42a along the lowermost region of the fluorescent target. As previously pointed out in the description of the operation of the tube, the vertical deiiection electrodes 58 are energized in an overlapping manner, or in other words, lthe voltage on at least two deflection electrodes 58 is changing at the same instant, and the beam is therefore always under the influence of the deflecting forces caused to be established by at least two vertical deflection elements S8. It may be easily discerned that this operational characteristic may be readily achieved in connection with all the vertical deilection electrodes 58 with the exception of the lowermost one. Therefore, in order to cause a strong attracting force to be established in the region of the lowermost one of the plurality of vertical deflection electrodes, a potential is applied to the electrode 56 which is positive with respect to the cathode potential of the electron gun 42. The attracting force or field established thereby causes the electron beam to be bent rather sharply toward the fluorescent target 57 after being deflected by the lowermost one of the vertical deflection electrodes 58. It is obvious tha-t the potential applied to the electrode 56 can be maintained at a constant value during the operation of the tube or could possibly be synchronized with the voltage signal applied to the lowermost vertical dellection electrodes 58. Further the value of the signal may be varied as desired to achieve the best deector. If desired, the conductive coating or electrode 56 may be an extension of the conductive target coating 57 and may be likewise maintained at the same positive potential with respect to the cathode potential of the electron gun 42.

Figure 6 shows an embodiment of the invention wherein the electron gun 60 is disposed within a cavity formed by the two mating glass panels which together comprise the unitary cathode ray tube. It will be noted that the electron gun is adapted to deliver an electron beam 61 along the vertical marginal edge of the tube. There is provided a ninety degree electron mirror 63 which is energized from a source of potential outside of the tube wall through a suitable electrical conductor. The electron mirror 63 is capable of eecting a ninety degree bend of the electron beam 61 to thereby cause the beam to travel into the region defined by the horizontal deflection electrodes 64 and the skirted accelerating electrode 65. The operation of the primary section of the tube comprising the skirted accelerating electrode 65 and the focusing electrodes 67 and 68 is the same as the operation of the corresponding sections shown and described with reference to the other figures of the drawings.

The embodiment shown in Figure 6 provides an extremely rugged and attractive unitary cathode ray tube. Such a unit is readily adaptable for wall mounting. There are numerous advantages effected by such a unitary cathode ray tube including ease of packaging, ease of mounting, ruggedness of design, elimination of the necessity of providing protection for the fragile electron gun assembly and others which are readily apparent to those skilled in the art.

One of the contemplated uses of the instant invention is in connection with aircraft navigation. In such use, the cathode ray tube would have to function continuously in all possible orientations of the airplane. It is conteniplated that information associated with the position and heading of the airplane would be displayed on the fluorescent target of the tube and in such event a scale-factor identical in both directions is to be provided on the display surface. The sweep speeds of the horizontal and vertical detlection systems are in such an application, equal, and the display or target area would be square.

The method of producing the cathode ray tube consists of preparing die forms of the proper geometry to provide the desired contours of the panels which form the resultant tube envelope. In the preferred embodiment, the two mating pieces are identical in design to effect a reduction in mold costs. The molding operation may be accomplished by any of the well known methods of forming glass into a desired shape. The molded glass panels are then cleaned in preparation for the application of the electrically conductive coatings which form the interval electrode structures of the finished tube.

The various electrodes are formed by applying an electrically conductive material to the surfaces of the molded glass panels. The electrically conductive material may be coated on the panels by any of the known methods such as painting, spraying, applying strips of electrically conductive material to the molded panels by the application of heat and pressure and any of the other conventional methods. It has been found that satisfactory results can be obtained by employing electrically conductive materials such as tin oxide or paints compounded from glass frit and colloidal silver.

Subsequent to lthe application of the electrically conducting material comprising the electrode structures, a fluorescent material, such as for example phosphor, is coated on the approximate portion of the surface of one of the molded panels in an area corresponding in size with the area occupied by the electrodes which comprise the vertical deflection system on an opposing panel.

The last stage of fabrication involves disposing an electron gun in the appropriate location and sealing the panels together. Sealing may be accomplished by any one of a number of well known methods. One preferred method of joining the two mating sections comprises sntering a low temperature glass frit which is disposed between the two sections during the final processing of the tube. The sealing operation could be accomplished wit-hin an evacuated environment or alternatively the panels may be sealed in vacuum tight relation and provided with a glass tubulation in the side wall of one of the panels. After molding, the tubulation would then be connected to a vacuum System which would be operative to effect a vacuum of the desired degree within the sealed envelope. At the end of the pumping cycle the tubulation then would be sealed off with a flame, thereby producing an evacuated space within the envelope.

It is obvious that the invention set forth and described hereinabove defines a cathode ray tube of the Aiken type which constitutes an advance over the known cathode ray tubes, in that the integral electrode and envelope arrangement makes it possible for the tube to withstand shock and vibration loads, having orders of magnitude larger than those which could have been survived by the `earlier designs. The elimination of a very large number of individual parts, together with their critical assembly tolerances, greatly reduces the detrimental shrinkages which would normally be expected in the manufacture of such a tube, and the arrangement is one which obviously results in the substantial reduction of costs, and the provision of an extremely economical type cathode ray tube.

The manner in which the novel concepts of the disclosure may be utilized in the provision of other cat-hode ray tubes such as set forth in the aforementioned Patent No. 2,795,731, facsimile tubes such as set forth in the copending application, Serial No. 494,386 which was filed March 14, 1955, polar coordinate tubes such as set forth in Patent No. 2,809,324, which issued on October 8, 1957 to L. A. Shanafelt, and Patent No. 2,821,656, which issued on January 28, 1958 to L. C. Foster, and in providing space discharge devices previously known in the art, will be obvious to the skilled, and are deemed to be within the province and scope of the following claims.

What is claimed is:

1. An article of manufacture comprising an envelope having at least a first and a second interior surface, an electron sensitive target means fixedly positioned in laminated relation with Iat least a portion of one of said interior envelope surfaces, and at least one strip of an electrically conducting material fixedly positioned in laminated relation with a second one of said interior surfaces to provide an electron beam deflection member for bending an electron beam from a path adjacent thereto into registration with said electron sensitive target.

2. In an electron space discharge device, an envelope having a secondary section including an electron sensitive target, an electron beam source, a primary section including means for directing the electron beam from said source in the direction of said secondary section, and a pair of electrically conducting areas coated on opposed inner surfaces of said envelope between said first and second sections for controlling the beam characteristics in its passage from said primary section to said secondary section.

3. An article of manufacture comprising an envelope made of at least a first section having a viewing Section on at least a portion thereof, a second section mated therewith including an electrically conducting material including a series of spaced strips coated on a portion of the interior surface of the second section in superposed relation with the viewing section to provide a deflection set for bending an electron beam into registration with the viewing portion of said first section.

4. An article of manufacture comprising an envelope having at least a first and a second interior surface in opposed relation, a series of electrically conducting spaced strips coated on one of said envelope inner surfaces, and an electron sensitive target disposed on at least a portion of the other of said envelope surfaces in facing relation with said strips.

5. An article of manufacture comprising an envelope having at least a first and a second interior surface, an electrically conducting area comprised of tin oxide coated on at least a portion of one said envelope surfaces, and an electron sensitive material coated on a cooperating portion of the other of said envelope surfaces substantially parallel with said first surface.

6. An article of manufacture comprising an envelope having a first section for locating a target and deflection means in spaced relation, and a second section for introducing an electron beam into said envelope along a given path including a series of strips of an electrically con ducting area xedly positioned in laminated relation with at least one inner envelope surface along said path for bending the beam from said path into the space between said target and said deflection means.

7. An article of manufacture comprising an envelope having a first section for locating a target and defiection means in fixedly-positioned laminated relation with a pair of facing inner surfaces of said envelope, a plurality of spaced electrically conducting areas fixedly positioned in laminated relation with a further surface of the tube which extends along one marginal edge thereof, and a further section including means for directing a beam along a path adjacent said conducting areas for deflection thereby into the space between said target and said deflection means.

8. An article of manufacture comprising an envelope having a first section for locating a target and deflection means in spaced relation, said target comprising electron sensitive means disposed on one inner surface of said envelope and said deflection means comprising electrically conducting means disposed on an inner envelope surface which `faces said one inner surface, `a plurality of spaced electrically conducting areas disposed along a marginal edge on the interior of the envelope, and at least one pair of electrically conducting areas disposed on said opposed inner envelope surfaces between said first section and said plurality of spaced conducting areas adjacent said marginal edge.

9. An electron space discharge device comprising an envelope, an electrically conducting material fxedly positioned in laminated relation with at least one of the inner envelope surfaces, and an electron sensitive material fixedly positioned in laminated relation with a second inner envelope surface in opposed relation with said first surface, and means for delivering a beam of electrons between said opposed surface portions for selective deflection from its path by said conducting material into registration with said electron sensitive material.

l0. An electron space discharge device comprising an envelope, electrically conducting means disposed on at least one of the inner envelope surfaces, electron sensitive means disposed on a second inner surface in opposed relation with said conducting means on said first surface, source means for delivering a beam of electrons between said opposed surface portions, and means for connecting energizing signals to said conducting means and said electron sensitive means to effect bending of the beam into registration with said electron sensitive means.

l1. An electron space discharge device comprising an envelope, an electrically conducting area disposed on at least one of the inner envelope surfaces, an electron sensitive target disposed in opposed substantially parallel relation with respect to said electrically conducting area, and an electron beam source means adapted to deliver a beam of electrons between said electrically conducting area and said target for deflection by the conducting area into registration with said target.

12. An electron space discharge device comprising an envelope, an electron sensitive target fixedly positioned in laminated relation with one of said envelope inner surfaces, an electrically conducting means xedly positioned in laminated relation with a second inner surface of said envelope which is located in facing spaced relation with said target, and means adapted to deliver a beam of electrons between said electrically conducting means and said target for selective deflection from its path by said conducting means into registration with said target.

13. An electron space discharge device comprising an envelope, at least one strip of an electrically conducting material fixedly positioned in laminated relation with at least a portion of one of the envelope inner surfaces, an electron sensitive target disposed on an inner envelope surface which is in opposed relation with said conducting material, and means adapted to sweep a beam of electrons between said conducting material and said electron sensitive target for selective deflection from its path by said conducting material into registration with said target.

14. An electron space discharge device comprising an envelope, a beam deflection means and a target disposed in spaced relation in said envelope, means for introducing a beam of electrons along a path which extends adjacent an inner marginal edge of said envelope, and means xedly positioned in laminated relation with an inner surface along said marginal envelope edge adjacent the beam path for bending said beam at different intervals along said path into the space between said target and said deflection means.

l5. An electron space discharge device comprising an envelope, beam deflection means and a target disposed in spaced relation in a given section of said envelope, means for introducing a beam of electrons along an inner marginal edge of said envelope, electrically conducting means disposed on opposed facing inner envelope surfaces between said marginal edge and said given section, and

13 means disposed on au inner surface of said envelope adjacent the beam path for bending said beam between said electrically conducting means and into the space between said target and said deection means.

16. An electron space discharge device comprising an envelope, a rst section including beam deection means comprising a plurality of electrically conducting strips coated on a portion of one of the inner envelope surfaces, and a target comprising a fluorescent material coated on an inner envelope surface disposed in opposed relation with respect to said conducting strips; means adapted to introduce a beam of electrons along a marginal edge of said envelope, electronic lens means including an accelerator and focusing electrode set disposed between said marginal edge and said iirst section comprising pairs of opposing surfaces in said envelope coated with electrically conducting material, and primary means for directing the beam lfrom its marginal edge path through said lens means and into the space between the target and the deection means comprising a plurality of electrically conducting strips coated on said marginal edge along the beam path.

17. An electron space discharge device comprising an envelope, beam deilection means disposed on a first inner surface of said envelope, a target disposed on a second inner surface of said envelope n opposing spaced relation with said rst surface, means adapted to deliver a beam olf electrons along a iirst inner marginal edge of said envelope, means for deecting said beam to a path along a second inner marginal edge of said envelope, and means for bending said beam from said second path into the space between said target and said deflection means.

References Cited in the le of this patent UNITED STATES PATENTS 2,259,165 Karasick Oct. 14, 1941 2,449,558 Lanier et al. Sept. 21, 1948 2,611,040 Brunetti Sept. 16, 1952 2,642,535 Schroeder June 16, 1953 2,677,723 McCoy et al. May 4, 1954 2,689,269 Bradley Sept. 14, 1954 2,795,729 Gabor June 11, 1957 2,795,731 Aiken June 11, 1957 2,831,136 Hanlet Apr. 15, 1958 FOREIGN PATENTS 697,922 Great Britain Sept. 30, 1953 698,799 Great Britain Oct. 21, 1953 1,075,268 France Apr. 14, 1954

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