DE1011918B - Cathode ray tube - Google Patents

Description

GERMAN

The invention relates to cathode ray tubes used for generating and displaying images either in essentially natural colors or in one color. The pictures that to be generated for playback on the tube screen, are by means of one or more on a screen surface of impinging electron beams provided with a phosphor coating, developed, in order to produce electro-optical effects on the screen surface, which are observed as light images can. The electron current hitting the screen surface can be controlled by modulation means and in relation to the screen area on which he strikes, are deflected two-dimensionally so that a grid is formed according to well-known patterns.

It has already been proposed to produce a phosphor coating on a screen on which the electro-optical images are produced by a series of strips, each width only one Fraction of the width developed at each point in the final raster formed. the Stripe lengths may be illustrative as corresponding to one dimension of the raster being developed be considered; "however, it appears practical, mostly with regard to the manufacture of the shield surface provided with a coating that the length of the phosphor stripe which exceeds a grid dimension somewhat.

For tubes in which a screen surface is formed in this way, it has been proposed that the separated strips of the screen cover be swept over or scanned by the electrical current; A stream of electrons is concentrated into a suitable scanning cathode ray beam which is deflected so that the scan path follows the length of the screen strips or in such a way that the rapid scan is across the screen strips. The invention is suitable for both modes of operation, but in the following, where reference is made to the scanning process, it is assumed as an example; "explains that the scanning takes place across 'the length dimension" of the phosphorus pull-over strips /., - ■ ^ -, · • _r - -It is already known, -in.r near a screen covered with • phosphorus''the ^r obßn' deservedly level • -Af t pure Gittörelektrotlfe. ' to arrange »-; A .golches lattice is intended -, "as" part of one: electric oils ¹

1 insenanordnuftg; ^; -zu · .-; work - ■ '(XJS A, -Pätefitsclmft

2 532 51; l:), -, ddfer ;; it- can act as a colourant electrode, or 'fulfill both ■ - above-mentioned' tasks: ■ - '<-; - ■; .- ■; '.. · ■■>■' --- '_' ■ - '^"V:.': .V \.;' - i

The invention-'is concerned-above all with'-der-Aus-j} ild-ung''deS "-Giiter-S: -selt) st-: and with-.the arrangement k ¹ Si) -Iehe» Lattert- in b ^ ziig-iani: "dm R'öhrenschirm.

Applicant:

Chromatic Television Laboratories, Inc.,
New York, NY (V. St. A.)

Representative: Dr. E. Wiegand, Munich 27,

Mauerkircherstr. 48, and Dipl.-Ing. W. Niemann,

Hamburg 1, patent offices

Claimed, priority:
V. St. v. America March 23, 1953

Robert Dressler, Elmont, NY (V. St. A.),
has been named as the inventor

In this context, for high accuracy of the operation of a cathode ray tube which is to be suitable for displaying images either in their substantially natural colors or in one color, it is particularly important that the conductive strips (usually in the form of wires ), from which the grid electrode is formed, must be aligned ^{exactly 1 with respect to the PhosphorstrHifen of the screen. "; '::.'} ■

It - is already a grid construction for a ■ ■ · - known tube, slotted in .a pair of; insulating Tfagteile in an essentially parallel position, 'which' are separated from one another by a distance that accommodate the conductors stretched for this purpose. Here, conductors that alternate with one another are parallel -: held and provided with connection points to which an electrical circuit can be connected; The "tensile stress of the wires ^T through the" tubular base "as well as a bridge element is taken: that is, the two" insulating rods "are" ~ v! File of a supporting frame ^ "- . ' ■. ■ '■ .- ■ L:;: ■'' ^r · ■, "" O

In the case of a cathode ray tube, the use of such a construction is not possible without further ado; for here "-the 'ProM $ m';" - how ^? the 'Zügspani nung-diöf Ί ^ ι-ϊάφ atif zusKiitien: is it; is indeed' already

nung-djöf'Dräiite auf zusbkien: is. It; is already C, * - 'known',: - 'with a "cathode ray tube on the carrier plate: dfeS' fluorescent screen" a support part is to be added 'to' - (a grid-like or sieve-like electrode is fixed at a distance is. 'This \'Sra.gteii'rW'iitl ^I 'v''by an äölßst-bearing Abstaiidiia: l: it »t ^< ahtn6ti? - formed ₎ ""der ^ri z
λ- dif / aü! it carries fixed & lemnite Tsägeirplatte.

709 587/148

1 Oil 918

- With the invention, another solution is proposed, which in particular also when using Very fine grid wires enable a high degree of dimensional accuracy and a tight tension of the grid wires guaranteed at a small, precisely maintained distance from the screen surface,

. The invention relates to a cathode ray tube with a arranged in front of the fluorescent screen Grid made of a large number of parallel wires that are alternately connected to each other.

The special feature of the invention is that the wires of insulating rods perpendicular to the Wires run and at the edge of the raster surface scanned by the cathode ray on one with a Luminous layer occupied transparent carrier plate are arranged at a distance from the luminescent screen are held and either on the insulating rods firmly connected to the plate or on further outside anchored parallel to the insulating rods and firmly connected to the plate conductive rods are so that the plate absorbs the tensile forces of the wires.

In this novel solution, the grid-like system and its supporting parts together with the Luminous screen is a unified and inseparable structure.

Furthermore, in a preferred embodiment of a cathode ray tube according to the invention each wire in the pair of support rods is held in place by enclosing or sealing.

A cathode ray tube according to the invention may have a pair of conductive parts, the are arranged outside the grid area and in the vicinity of the ends of the frame and on the screen base area next to each support rod are held at different distances from this so that the Wires extending between the support rod and the conductive parts, alternately different Angle both with respect to the plane of the wires stretched parallel between the support rods as well as the Form the plane of the screen base area carrying the support rods, with each wire carrier in addition to an insulating part comprises two longitudinally extending electrical conductors to soft the wires are connected alternately.

Furthermore, each support rod can expediently be removed by a distance from an adjacent rod be, which is at least equal to one dimension of a grid that is in a scanning process on the Screen surface is swept, and that the wires from each other by at least one dimension Elementary surface are removed, which is to be resolved on the screen.

A method of making a grid-like structure for placement in the vicinity of the luminescent screen of a cathode ray tube is, according to the invention, that the grid wires on stretched glass support elements and pulled through slots in the glass that the wires in two Groups are divided and all wires of both groups are connected to each other, and that the. glassy Support elements are preferably fastened directly with their surfaces on the carrier plate.

It can be a dome-shaped lattice support element with a dome-shaped cross-section Attachment to the screen base.

Furthermore, the grid wires are expediently in the Slitting the support elements held under a tensile stress that is sufficient to-the sagging to prevent between the support elements so that they are taut parallel to each other.

Assuming that the screen surface is suitable for three-color operations, the separate Phosphor strips that have the properties of fluorescing in different colors when excited, can be arranged on the screen surface according to a repeating color cycle. A such a color cycle can, for example, be a

xo patterns follow, according to which light in the colors red, green, blue, green, red, green, blue, green etc. is produced.

Because the proposed color cycle has twice as much phosphor-coated stripe areas to produce green light than those used to produce red and blue light, it is common in order to achieve a correct color balance, the stripes, which are green light, are desirable produce to make it approximately half as wide as that

ao for generating red or blue light. The Stripes to generate green light, for some tubes the width of the other strips can also be equal be. The grid conductors or wires, when supported, are over each of the phosphor coating strips, that produce the red and blue light, electron-optically centered. When to the lattice ladder, which are centered with respect to the phosphor stripes, different potentials are applied and if a Electron stream in the form of one or more cathode ray beams through the grid onto the Tubular screen is directed, then it turns out that, depending on which of the grid conductor is more positive is opposite an equilibrium point or element, the lattice opposes the path of the electron beam determines the shade and thus the light color that is visible. On the other hand, if the lattice ladder in be kept in such a state that there is no electric potential difference between them then every electron stream directed towards the screen is directed towards the center between the conductors centered. For the example mentioned above, this means that green light is generated. You can do this the various grid conductors in the illustrated example as from each other by distances between one Imagine half and a whole elementary surface separately on the screen surface during image generation should be resolved.

If the image is produced on a tube with a viewing window about 50 cm wide, then the grid wire spacing between the centers is on the order of 0.38 mm. One Wire thickness on the order of about 0.05 to 0.075 mm is useful here.

The invention is explained in more detail below with reference to the drawing, for example.

Fig. 1 shows in schematic form a side view, partly in section, of a cathode ray imaging tube to which the invention is applied is;

Fig. 2 is a partially broken away view of a portion of the grid system according to the invention; seen in the direction of the arrow on the bottom of the tube shown in Figure 1; · ''

FIG. 3 is a section of that shown in FIG

Grid system along line 3-3 of Figure 2;

Figure 4 is a view partly in section the line 4-4 of Figure 1 illustrating the location of the grid system in the tube;

Fig. 5 is a greatly enlarged partial sectional view to illustrate the relative position between

5 6

the screen surface, the grid conductors or wires of this type, the electron- and the grid support part for the spatial definition of the beam at a relatively high speed against the Grid wires in relation to each other and to the screen.

Screen area; In the case of the tube to which the invention is

Fig. 6 is a sectional view essentially turning 5, it is assumed that the elec-

corresponds to the arrangement of FIG. 3 and, in particular, the electron thrower corresponds to the flow of the emitted electrons

a form of connection of the grid conductors for loading into a single electron beam that forms against

fastening at contact points of the tube to the screen surface over most of the

Conclusion on outer supporting parts reproduces; Distance between the slingshot and the glider

Fig. 7 shows an enlarged partial sectional view under the influence of an accelerating voltage geeiner modified type of connection of the grid conductor is aimed at, which is in the order of magnitude of about a bus bar, this cut being a quarter of the tension that is at the moment Change of the impact on the screen shown in FIGS. 2 and 6 is needed. There reproduces final forms. those used to deflect the electron beam

The drawing, on which devices are now known per se for better comparison, are shown in FIG. 1

State of the invention, reference is made to the drawing is not shown. It is therefore sufficient

a grid system, generally designated 11, which is used to say that the electron beam is developed on

the widened end of a highly evacuated ca- his way against the screen 15 under the impact

method-ray tube piston, which is generally labeled with 12 bevel electromagnetic or or and electro-

is drawn, is arranged. The 20 static fields drawn here, which in directions perpendicular to one another

The shape of the tubular bulb is purely schematically different and perpendicular to the flow of electrons from

chooses; Instead, some other sling could work against the screen, two-dimensional

known type of metal or glass bulb can be used sional be deflected.

the. In either case, the tube has essentially a tube of the type described herein borrowed frustoconical piston part 13 25 such, in which a grid system, the general, which is denoted by 11 in an essentially flat viewing window 14, adjacent to the phosphorus, which is arranged in the tubular screen 15 covered by an arrow in FIG. 1. One drawn direction is considered. such grid electrode is suitable at one potential

This viewing window 14 usually consists of working opposite the electron source (it can glass, so that an image made within the tube on 30 NEN modifications is generated to different a phosphor layer, from the outside to produce color effects, as they will be described later In many types of tubes, the phosphor is (be), which corresponds approximately to the potential of the anode layer directly on the inner surface of the viewing window of the electron gun.
14 applied. In another type of tube (which, as is common practice here, is shown specifically on the phosphor overlay), the phosphor layer on the layer on the transparent screen 15 (the type of surface of a transparent screen applied phosphor overlay has already been described) can be one that is commonly used with 15 and is applied in a corresponding metallic film on the side of the phosphor coating which is supported by the lattice system 11 growing inside the tube piston. It is as close to the viewing window as such a metal film is electron permeable. The metal film from the standpoint of easy assembly 40 allows electrons to pass through it and a simple tube construction is possible. The embodiment shown here is of a type of screen, but it forms a barrier which offers some advantages from the point of view of the ions that reach the screen and simplify the manufacture of tubes on it, although the known ones It is important to note that if the tube is fitted with an im 45, it is important to remember that this can cause unwanted ion spots. At the same time the metal film is conductive and substantially flat window 14 is made, which allows the application of a relatively high voltage, phosphor layer, as indicated above, also on the measured in relation to the grid system to the screen. Window can be attached. This working voltage difference can in general

At the opposite end of the tube, mine is about two to four times the voltage.

frustoconical part 13 into a neck part 16 about 5 ° difference between the electron-

at its end, essentially at the completion source and the final accelerator of the electron

of the manufacturing processes, a base plate 17 occurs, which has already been described and

has been consolidated. The potential at this base plate is essentially the same as that

suitable tips or pins 18 for attachment to grids can work.

a tube socket or for connection to a 55 As a result, in the area between the

external circuit provided. In the tube neck lattice system as a whole and the screen a loading

16 one or more suitable electron acceleration fields are developed, which differ from the

Contain fling, from which electrons emitted source to the screen moving electrons on

directed against the screen, at a relatively high speed on impact

bouncing on him. 60 brings to the screen. At the same time leaves the applied

The electron gun exhibits tension in a known manner due to the proximity of the grid system

the common cathode together with its and the screen converging electric fields

Radiators and selected acceleration electrics are created, which form another point-like collection

den or anodes in connection with various of the electron beam when it reaches the screen,

Grids or modulation electrodes. Bring 65 in some. With those in the manner described above

Tubes, a second anode is provided, which is used to conduct a plurality of arranged conductors of the grid

Accelerating the developed electron stream of cylindrical electron lenses from one of the number of

serves when he is in an electron beam from concen-conductor in the lattice corresponding number in the area

inert cross-section is formed on the between the grid conductors and. formed the screen,

Screen surface can have its focal point. With a 70 so that every incoming electron beam in a

7 ₈ ill ¹

considerably reduced cross-section is collected. S tookey: _r »Photosensitive Glass« ,, describe,]?,. Wej- due / Ms small in comparison Gitterdräntdurchinessers't'ere types of this type of glass are also generally au, f is equal to the cross section of through the grid S. 3951 the magazine "The Glass .Industry"^"v-om!:!'| against the phosphorus-coated screen "on September 24, 1951. '"· ·.;, ■";> scanning beam is only a negligibly smaller 5 In short, -the, glass of a kind, -that,' a * |; part of the scanning beam is removed by the grid wires- ultraviolet- ¹ radiation, can .on .the phosphorus coated screen by overall exposure to _"catch suitable ';, · un ^ t, so that most of the freed electron extremely accurately shaped."t'ronen by a photographic negative / IIJ ^. . The negative is collected. '. ■ "the image or pattern of the desired slits oiü ^ j

If we now consider the foregoing in the light iq grooves, so that when the glass is exposed, that of the arrangement of the grating, we assume that the light exposure which takes place is such, the screen surface. 15, a glassy material, so that with the utmost accuracy the group consisting of an image can ^ .ψ suitable savings rods 21 for supporting the grid or slots is photographed, in _'which: drähte.nahe the opposite edges of the grid wires 25 attached and held / thrower}. ' the grid areas are attached. Under the 15 should. The spacing of such slots is consistent with the assumption that scanning by the developed one already described. '', .-. '

Electron beam in a direction transverse to the -It takes about the process of slot formation 'after "

If phosphorus coating strips of the screen take place, the exposure will only be told that the glass is. these support rods are arranged so that they are parallel rod to a controlled heat treatment to the longitudinal direction of the grid, as shown in "20, the-the development of an image in FIG .. distance causes veran- glass This is generally done through shows is such bars any formation of lithium silicate crystals may be in _the:; | ^ ρ, have ρ-Qüerschnittsförm, but has been found that ned areas, the actual.. Image is daqürl | ij a rod-of circular cross-section, which develops in that-the glass of a heating to a ", center is cut through lengthways, is particularly suitable 25 temperature of about 650 ° C for a certain thereby becomes a stat) of essentially half-duration, generally of the order of magnitude of a circular cross-section, which is exposed to about -2 hours. This tubular heat shield can be attached by this heat-tube screen. ■. - ". treatment, a milky white image appears in the

In a "preferred embodiment of the otherwise transparent glass. When the glass is then in an invention, the lattice support rods 21 are immersed on the glass - 3 ° solution of hydrofluoric acid, SQ ₁ screen element 15 - attached parallel to each other selective detachment · of its glassy! distance; -between: the rods corresponds to the property of the stripped glass from the so-called desired span of the .wires "above the heat-developed," picture to be coated. On the curved outer surface described cutting or grinding of the support rods 21 are suitable grooves "or 35 glass rods - for the purpose of producing the. Slots, t; j clearances.23. For receiving and holding the grid - can also be here the depth of the generated image j f ;; ladder, or ;; - wires,: which are designated by 25, formed in any suitable manner by varying the duration and intensity of the Εχρρ- .ψ s can - rening of the glass, in the case of ultraviolet radiation ..... Jp sipiedeae .. methods for forming the slits or through the negative - regulate accordingly. D ^ ^: | p! Nuterf ^ applied .; will. "It is essential, however, that the 4 ° to be selected is usually experimentally" ef, -., V | p eln-Tiöher "the degree of accuracy of the distances is observed. If it is known that the depth e of the intervals; | K , if made just enough for those tube eihe.äuB'ersfgenaue in bars 21 "Werdi ^{^:} || j operation" is to be obtained; '''V'.'. If you want to attach the wire exactly, "dig '1 | ίί

; In one embodiment, for example, irradiation times are set accordingly. "■ _TV ^ fairy Νμΐεη .o * of the recesses 23 'to the" way, overall 45 ". In the Ausführungsfoim shown 5 schnitteivdaß. In FIG. 21 before the rod seinem.'Einbau in" the ζ, -Β. the slot 23 is made deeper than the diameter of the tube with a spacing in front of a large number of knives of the L cutting head used to form the lattice or grinding edges in the shape of a 25 , while in the arrangement according to Fig. 6 f rotating spindle .or a TDorries arranged slot in the rod 21 to a depth is guided .astl .. The 'rod will' ... then with .dem rotating 5 ° essentially , DEM diameter des'das grid cutting or grinding tool in calling, brought forming conductor 25 corresponds. ^It! is, Cdies a BG and the grooves of the desired depth of manufacturing "measurement question. . . . , ,,. ^

posed. A cutting or grinding seam of this type "after the glass rods 21" have been cut to size, "ger consists of" extremely hard cutting or grinding * - ground and on photographic other similar, W.§g | material, so that the grooves in the relatively soft glass 55 with the desired number of slits provided, SiHfI ₁ iii, are exactly uniform .; Distances from one another, where all these slots can be cut exactly from one another, which are decorated with the distances between the glass rod and the transparent cutting or bevelling edges of the machined faceplate .15.be fastened ,. Bisjang wuc ^ ie ^ j teten. Cutting tool exactly, correspond ,.This.e. Most "tubes, the · phosphor coating in, Fq ^ production method, wjjd only as a possible type of the 60 of the already mentioned strips attached. Ejri.SQjGtlgr "Preparation of the sticks mentioned. ~ \ V. .... , ', ... -, coating. Is in. The drawing, general, .with, - " ^ i- ^: "p6-;, _ According to an embodiment that can be used as required. "If" they are not part of the object of this invention, the rods made of a glass type can belong to the invention, so can, docE also, be methqqfif which, through photosensitivity "Opalescent" is. For application., Dex phosphor coatings according to theB% -A glass of this. Type is as; " light-sensitive »Opal- 65 'lestigen .. der rods 2Γ am> .S, chirm apgewendet w ^^ a ^ .. glas«, "beliannt.". The _.; Company, Corning -Glass. Works, """Der Üprztig "The metal film," which is applied to the morning, "New York," is the manufacturer of such a glass in the usual way. äri. The properties, dj, eses'Glase / s. Are in "der.'Zeit- are with -einem.soldaen ^ DurciinieeserVTOer ^ || · ^; script.» Indus-tria, i ;. and ".Engineerj- ng. Ghemistry, « _? .such O.icke - ;. bemes, sen> that, naeh ^: Anbri ^ H |! ^ _{] i} | er 'April 1949 ^ .S.; ß563.is _: 8ol "_;v" in "derlArbeit, yon-S . ti .. 7 ° .S.tä-beder reason deir-slits ^. 'in.welcfeen.die leiiet ^ lpn

1 Oil 918

9 10

Elements of the grid are to be attached to strips or wires 25 from which the grid is formed from the screen plane at such a distance, mounted so that they bridge the slots 23, finds that there is a separation between the metal film into which it fitted and into which it is drawn taut on the screen and the grid wires are assured so that any sagging of the grid conductors is that the desired distance between grid 5 or wires in the space between the two insulating and screen corresponds. In most types of tubes rods 21 is eliminated. If the wires or conductors if this distance is only a fraction of a distance held in such a position, they will be fixed Inches (generally forms about five times the anchored width.

a series of phosphor-coated strips for this purpose, various measures can be taken

full color cycle). 10 can be applied, but in the arrangement described in

In order to achieve the lowest possible loss in the ovens in FIGS. 2 and 3, for example, the position by breaking the glass rods or the like is achieved when the conductors or wires are so taut, it is when they are finished prepared tube and in a taut position to preserve the baked off, it is desirable that the glass from which the stands S are formed between the lattice member and the screen rods 21 have a coefficient of expansion, a suitable glass surface. Metallten which is the same or substantially the same as the connection method used to taut the transparent faceplate 15 so that no conductors or wires continuously occur in the recesses to different expansion which fasten a breakage. The ease of tensioning is due to the heat caused by the rod, which can be seen that the wire diameter only in which the tube is attached in the baking process is on the order of 0.08 mm, so that the wire becomes. If these conditions are met, the weight is completely irrelevant; As a result, it is possible to seal the wires in the grooves 23 sufficiently to fuse the glass rods 21 and the faceplate 15 to hold them in place and to prevent the glass rods 21 from swaying in the exact mutual relationship. prevent. It is also possible to have the lattice wires spaced apart and aligned in parallel so that the 25 grooves through various types of cement conductive parts 25 of the lattice when they are fixed between the bars, one of which is stretched under the bars and in the shaped slit drawing »Sauereisen« is well known, are definitely accommodated, which is exactly parallel to the suitable.

Extend edges of the phosphor strips. If the wires or conductors 25 in the spacing

other fastening methods are also used, rods 21 are sealed or glued on the, z. B. using potassium silicate or the wires alternately connected to each other if Fused glass, in order to have only two connecting means to want the grid to work in such a way to name. that it is in a tube for multicolored or single

Can be used for some working conditions and especially colored image reproduction. Of the when using so-called photographic glass 35 a set of wires is attached to a bus 27 and the expansion coefficients of the glass rods21 the other on a similar busbar 28 and the transparent faceplate 15 does not exactly secure at opposite ends of the to match. In these circumstances it is he-wires. The ends of the wires of each set that aren't desires a stepped connection between those connected to a bus bar can then, Provide both components to the inner 40 as particularly shown in Fig. 2, close to the tensioning to distribute and cut off a break due to stand bars. It can then Difference in the expansion of the two compo- suitable connections from each of the busbars nents to avoid. It should be noted that the 27 and 28 lead to the outside of the tubular piston Making such a stepped connection and will be as shown at 29; here go the the selection of the gradation between the rod-shaped connections by any one desired gen part in itself and the transparent carrier for this way produced melting point in the tube ensured must be that a precisely defined room wall wall through, or they lead to a button Recording of the connection is present, thus connection within the tube, at the opposite of which the desired separation between the lattice conductors placed side a cap can be attached to and the metal film on the phosphor coating of FIG. 5o connects to an external circuit 29, 30 Shield plate is guaranteed. to manufacture.

It is of course to be understood that instead of the above, if in FIGS. 2, 3 or 4 the better

Use of stepped connections for the sake of expansion clarity is not shown that the coefficient of the glass screen surface 15 that of the busbars 27, 28 of the screen member itself ge-lattice support rods, z. B. the rods of photographic 55 can be worn, it is a training Glass, can be adjusted accordingly. Such changes are usually preferable. The order The expansion coefficient of the glass is generally such that the wires, or conductors, are made from materials from which the screen is made cannot in themselves be made equal are brought about in the manufacture of glass; are sufficiently rigid to support the bus bars, so however, it is generally more difficult that, generally speaking, such bus bars appear The coefficient of expansion of the rods can be of any desired type on the surface of the screen speaking to that of the screen to change. can be attached in a manner similar to that shown in Anyway, the problem of the various expansion is shown. For this type of construction Coefficients of tension of the rods and the screen surface cannot be different types of connectors to be combined critical. 65 keep the two elements applied, however

For purposes of illustration the gap would have a form which is suitable, during the between the grid conductors and the metal film 24 of the frying sufficient possibility of movement zuzumit phosphor coated face plate, FIG. Blank 5, the different expansions of the measure S, the entire the length of the To compensate grid glass and the busbar, the ladder must be strictly adhered to. The ladder 70 is the most suitable for this.

1 Oil

There can be several types of brackets for attaching the entire framework from the transparent, phosphor-coated screen and the grid wire support rods carried by it and applied to the grid wires themselves. This particular construction in itself does not form part of the present invention and is therefore only indicated schematically by support arms 31 and 32 (Fig. 4), which can be in the form of ribs. VVo these parts are made of metal and the frustoconical part 13 of the piston 12 is also made of metal, they can be attached in a suitable manner to the inner wall of the tube welded on and then with the help of any conventional or any glass-to-metal connecting means that the correct and desired expansion allowed to be attached to the transparent faceplate. At a Another embodiment can surround the glass screen with a metal frame and then the connection be made to the frame. If the tube is made entirely of glass, the support rods are or ribs 31, 32 usually also made of glass that is the same or approximately the same has the same expansion coefficient as the screen. The arrangement can be fused to to connect the tube wall and the faceplate.

In a modified form of the invention, it will often be desirable to provide the spacer bars 21 with the The incised grooves or grooves can only be used as a fork or saddle into which the lattice ladder is inserted and be arranged. Then, preferably by melting or otherwise fastening on a rod attached to the surface of the base plate, to which a conductive connection is established. These rods are indicated in Fig. 6 as metal rods 33, 35, which are attached to the outer edge of the transparent Faceplate 15 by any suitable glass-to-metal connecting means are attached. Such metal rods can be held in arms or in any other suitable manner to allow expansion and allow contraction, provided that they have different expansion properties compared to the base. To use such sticks, the grid wires are arranged so that alternate wires conduct the conductor 33 and others alternate Wires overlap the conductor 35, and in this position the wires are properly positioned welded on or otherwise permanently connected. This type of permanent connection ensures firstly a good electrical contact between the wires of the grid and the conductor and secondly one permanent position of the grid wires in a taut condition and exact distance to the screen plane.

It can be seen that in the embodiment in which the conductors or wires 25 are attached to the bus bars attack according to FIG. 6, the two conductive parts 33 ^ and 35, which are located outside of the support rods 21 are arranged so that the conductors or wires 25, when bent to touch them, Form slightly different angles to the conductor plane in the area between the support rods 21. In order to there is no possibility that the conductors or wires 25 attached to the outer bus bars 33 are touching the bus bars 35 that are closer to the support bars, it may often be desirable to use the inner part 35 with a cross-section diameter which is slightly smaller than that of the outer part 33 to produce. In this way, those conductors in the grid, which are to the outer part extend, held above the busbar located closer to the glass support rods 21 will.

By alternately connecting the grid wires to the separate conductors 33 and 35 arrangements can be created through which different; Alternating potentials opposite the screen Head of the grid .can be placed to ttetf Tube a color change of the t% t already described produced when the tube is in operation. "'I

In a modified embodiment, which is shown in FIG. 7, the conductor bars 33 and 35 can be replaced by an insulating bar 39, preferably in the form of a glass part, which is melted onto the screen plate 15 or attached to it in a different manner. The glass rod 39 contains a conductive part 41 which extends over its entire length and is held precisely in it to allow a suitable weld or braze connection between the conductor 25 of the grid and the conductor 41. A S (Jl ^ e of connection is known, so that a-going eftir zelne description is omitted. It is sufficient dai + to be noted that d in such an arrangement ^ jf conductive member 41 may be connected in any manner to an outer ¹ circuit , whereby the results achievable with the arrangement described above are achieved.

Claims (7)

Patent claims: 1. Cathode ray tube with a grid arranged in front of the luminescent screen of a plurality of parallel wires which are alternately connected to one another, characterized in that the wires of insulating rods (21) which run perpendicular to the wires (23, 25) and are arranged at the edge of the raster surface scanned by the cathode ray on a transparent carrier plate (15) covered with a luminescent layer (24), held at a distance from the luminescent screen and either on the insulating rods (2 ¹ Jl) firmly connected to the plate or on further Conductive rods (33, 35) arranged outside parallel to the insulating rods and firmly connected to the plate are anchored so that the plate absorbs the tensile forces of the wires. 2. Cathode ray tube according to claim 1, characterized in that each wire in the two Isolierstäben (21) is held by inclusion. 3. Cathode ray tube according to claim 1 or 2, characterized by a pair of conductive parts (33, 35), which are arranged outside the grid area and in the vicinity of the edges of the carrier plate (15) are and on the support plate (15) next to each insulating rod (21) in different Distances from this are kept so that the wires between the insulating rod and the conductive parts extend alternately different angles both with respect to the plane of the wires stretched parallel between the insulating rods as well as the plane of the carrier plate So each wire support in addition to each insulating part two in the longitudinal direction it extending electrical conductors (33, 35) Uff to which the wires alternately ai% e are closed. '' 1 Oil 918 4. Cathode ray tube according to one of the preceding claims, characterized in that each insulating rod (21) is spaced from an adjacent rod (21) by a distance which is at least is equal to one dimension of a grid that is generated during a scanning process on the screen surface is coated, and that the wires (23, 25) from each other are removed by at least one dimension of an elementary surface on the screen should be resolved. 5. Cathode ray tube according to claim 1 to 4, characterized in that the insulating rods one have approximately dome-shaped cross-section and with the flat part of the dome on the carrier plate are attached. 6. Cathode ray tube according to claim 1 to 5, characterized in that the grid wires (23, 25) are held in the slots of the insulating rods (21) under a tensile stress that is sufficient is to avoid sagging between the insulating to prevent rods so that they are taut parallel to each other. 7. Method for assembling a grid-like structure with the fluorescent screen of a Cathode ray tube according to one of the preceding claims, characterized in that the Lattice wires stretched on glass support elements and pulled through slots in the glass that the wires are divided into two groups and all wires of both groups are connected to each other and that the glass support elements, preferably directly with their surfaces, be attached to the support plate of the luminescent screen. Considered publications: German Patent No. 820 614;
U.S. Patent Nos. 1,937,202, 2,568,448;
Proc. of the IRE, October 1951, p. 1242, Fig. 2. 1 sheet of drawings