CN1360331A

CN1360331A - Color cathode-ray tube

Info

Publication number: CN1360331A
Application number: CN01130386A
Authority: CN
Inventors: 松馆法治
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2000-11-22
Filing date: 2001-11-22
Publication date: 2002-07-24
Also published as: JP2002163999A; KR20020040572A

Abstract

To realize a press mask having a large radius of curvature by self-correcting doming. As a material to constitute a shadow mask, a single plate body composed of a compound gradient alloy plate wherein an alloy element has a concentration gradient continually decreasing from one face toward the other.

Description

The specification color cathode ray tube

Background of invention

Invention field

The present invention relates to a kind of color cathode ray tube of shadow mask, or rather, related to a kind of highly reliable color cathode ray tube, it can improve the strength of materials of shadow mask, can improve etching characteristic and forming property, and can reduce thermal deformation.

The description of relevant technologies

Color cathode ray tube for as the display unit of the monitoring arrangement of communication equipment in recent years or colour picture receiver is developing a kind of planar technique rapidly, and it makes the plate (panel) of composing images display surface flatten.Particularly, when the shadow mask of the die forming of taking to have along continuous straight runs and vertical direction curved bel hole surface, the plate of the color cathode ray tube on plane (flat tube) has the outer surface and the inner surface that the ratio of curvature outer surface curvature is much bigger that are approximately the plane.

Summary of the invention

As the technical assignment of design during this flat tube, can enumerate the strength problem of shadow mask.Though with the curvature of the interior surface curvature that the is similar to plate shadow mask that is shaped, compare with the disc pipe that inside and outside surface is crooked simultaneously, flat tube has the small curve of plate inner surface, thereby can only make the shadow mask curvature of flat tube also little.Therefore, be difficult to keep intensity to resist the thermal deformation that the what is called protuberance phenomenon by shadow mask surface with holes produces, thermal deformation is to cause because of mask temperature that electron beam bump in the work causes raises.In addition, also be difficult to keep resisting the actual strength of shadow mask depression, impact and so on.

As the material that guarantees this class shadow mask intensity, that has adopted that the doping cobalt is produced in conventional invar (Invar) material mixes cobalt invar material.

Though once adopted the al deposition steel as material for shadow mask, in recent years except the definition of trying hard to improve image and make screen more flat, adopted the invar material.Being used to improve the cobalt invar material of mixing of shadow mask intensity, to have guaranteed that the conventional invar material of strength ratio increases about 20%, and suppressed the above-mentioned distortion of shadow mask.But, the shadow mask that the doping cobalt is produced in the invar material has several shortcomings, comprises that (1) has increased cost owing to cobalt is very expensive, and (2) are owing to the fine etching efficiency that reduced of the corrosion resistance of cobalt, (3) reduced machinability, (4) have reduced magnetic characteristic.

Therefore, the purpose of this invention is to provide a kind of color cathode ray tube of plane formula, it has a shadow mask that can reduce shortcoming that conventional shadow mask has.

The of the present invention peculiar main points that achieve the above object are to be: the material for shadow mask that color cathode ray tube adopted is to be made by iron material, it is formed by the plate body of a kind of alloying element that mixed, and the concentration gradient with alloying element, element reduces to another surface of plate body gradually from a surface of plate body.Peculiar being constructed as follows of the present invention.

(1) in having a color cathode ray tube that vacuumizes a shell and a shadow mask, shell has comprised that one is coated with the plate with the multicolour fluorophor, a neck that electron gun is housed and a glass neck that is connected with neck with plate on inner surface, shadow mask is mounted close to the fluorophor that is coated on the plate inner surface, and has a large amount of colored selecting holes, wherein

The material that constitutes shadow mask is formed by a veneer body, it is made by the iron material that contains a kind of alloying element, the veneer body is a complex gradient alloy sheets, has the concentration gradient of alloying element, and element reduces to the surface of electron gun one side continuously from the surface of fluorophor one side.

(2) when the veneer body that constitutes the complex gradient alloy sheets contains nickel as alloying element, near the veneer surface of fluorophor one side nickel content is configured to be not more than 45wt% (percentage by weight), and near the nickel content the veneer surface of electron gun one side is configured to be not less than 0wt%.

(3) in said circumstances (2) (the veneer body that wherein constitutes the complex gradient alloy sheets has comprised nickel as alloying element), near the veneer surface of fluorophor one side nickel content is configured to be not more than 36wt%, and near the nickel content the veneer surface of electron gun one side is configured to be not less than 16wt%.

(4) be formed on the colored selecting hole that forms in the shadow mask by dot matrix way, whole shadow mask forms a kind of by the type that self keeps its shape.

(5) the colored selecting hole that forms in shadow mask is formed the many continuous lines that extend along direction, along the bearing of trend in hole tension on the member that forms the wire hole.

(6) the colored selecting hole that forms in shadow mask is formed many slits, the slit longitudinal axis extends along a direction, whole shadow mask forms a kind of by the form that self keeps its shape, perhaps along the long axis direction of slit-like opening or along long axis direction and short-axis direction tension on shadow mask.

The present invention is not limited to above-mentioned structure and the structure that will illustrate in embodiment described below, it is contemplated that various modifications and can not deviate from technological concept of the present invention.

The accompanying drawing summary

Fig. 1 is the constructed profile of a shadow mask essential part, and first embodiment of color cathode ray tube of the present invention has been described.

Fig. 2 is the perspective view of a mask structure, and it is installed in the color cathode ray tube of first embodiment of the invention.

Fig. 3 makes the explanation view that complex gradient alloy sheets method is given an example, and plate has constituted the material for shadow mask that is used for color cathode ray tube of the present invention.

Fig. 4 is a perspective view, and the complex gradient alloy sheets structure that obtains in manufacture process shown in Figure 3 has been described.

Fig. 5 A and Fig. 5 B are the views of having represented that nickel concentration distributes in the complex gradient alloy sheets shown in Figure 4.

Fig. 6 is a schematic sectional view, has illustrated that the internal stress of complex gradient alloy sheets distributes, and plate has constituted the material for shadow mask of the color cathode ray tube that is used for the embodiment of the invention.

Fig. 7 A, Fig. 7 B and Fig. 7 C are the illustrative views of the actual image of seeing on the surface plate with deep camber inner surface, are assembled in this panel as the molded shadow mask of the invar material of comparative example of the present invention one of at this moment.

Fig. 8 A, Fig. 8 B and Fig. 8 C have the illustrative view of the actual image of seeing on the surface plate of curvature at along continuous straight runs only, and this moment, a shadow mask that is molded as the periphery shape was assembled in this panel.

Fig. 9 A, Fig. 9 B and Fig. 9 C are at the illustrative view with actual image of seeing on the surface plate of unusual small curve inner surface, one of this moment adopt the molded shadow mask of material for shadow mask of the embodiment of the invention to be assembled in this panel.

Figure 10 is a schematic sectional view, and an example of the whole structure of color cathode ray tube of the present invention is described.

Figure 11 is a schematic sectional view, and another example of the whole structure of color cathode ray tube of the present invention is described.

The preferred embodiments of the present invention

The preferred embodiment of color cathode ray tube of the present invention is described below with reference to accompanying drawing.

Fig. 1 is the constructed profile of a shadow mask essential part, and first embodiment of color cathode ray tube of the present invention has been described, and Fig. 2 is the perspective view of a mask structure, and it is installed in the color cathode ray tube of first embodiment of the invention.

For shadow mask 6 as shown in Figure 2, the district AR with holes that constitutes shadow mask 6 major parts is shaped as a curved surface, it is corresponding to will be at the interior surface curvature of the panel of following explanation, and is fastened on the cover frame 7 along the peripheral part 61 of approximate tube axial direction bending, has constituted a mask structure thus.Cover frame 7 is provided with pendulum spring 8, and spring cooperates with stud pin, and stud pin is contained on the inwall in panel skirt section (its structure will in following explanation) in the mode of projection.

The material for shadow mask that constitutes this embodiment shadow mask 6 is made by iron material basically, and it comprises the nickel as alloying element.Shadow mask 6 is made of the veneer body of complex gradient alloy sheets manufacturing, wherein the complex gradient alloy sheets comprises the first composite portion 6A and the second composite portion 6B, the first composite portion 6A has formed Fig. 1 along Z-direction (tubular axis: one of surface arrow Z), it is phosphor screen one side of nickel content maximum, the second composite portion 6B has formed another surface along Z-direction that faces toward with above-mentioned surface, i.e. electron gun one side of nickel content minimum.

Nickel content reduces to second composite portion continuously from first composite portion.The veneer body that reduces continuously from side surface of veneer body to another side surface nickel element of veneer body is called " complex gradient alloy sheets " the present technique explanation.

In Fig. 1, schematically represent with " * " as the nickel element of complex gradient alloy sheets alloying element, the nickel content difference usefulness along the complex gradient alloy sheets cross section that constitutes shadow mask 6 between phosphor screen one side and electron gun one side * dense degree represent.

In other words, the complex gradient alloy sheets can be called a veneer body, and it is at first metallic plate with first composite portion 6A and have in the mesozone between second metallic plate of the second composite portion 6B and have continuous alloy zone.But this complex gradient alloy sheets is different from conventional so-called cladding sheet material, and the latter is formed by stacking by two dissimilar metallic plates.In the cladding sheet material, can not see the gradient of the alloying element content shown in Fig. 1.

The first composite portion 6A can be formed by the Fe-Ni alloy plate, and the second composite portion 6B can be formed by iron plate, and wherein the nickel content of the second composite portion 6B can be set at 0.Or the first composite portion 6A can be formed by the big metal of nickel content, and the second composite portion 6B can be formed by the little metal of nickel content.More particularly, the first composite portion 6A can be formed by invar material (nickel-ferro alloy that contains 36wt% nickel approximately), the second composite portion 6B can be formed by the stainless steel that contains 16wt% nickel approximately, perhaps the first composite portion 6A can be formed by the stainless steel that contains 17wt% nickel approximately, and the second composite portion 6B can be formed by the stainless steel that contains 16wt% nickel approximately.

In addition, the first composite portion 6A can be formed by permalloy (nickel-ferro alloy that contains 43wt% nickel approximately).Here, consider magnetic characteristic or material cost, preferably limit nickel content and be not more than 45wt%.

Produce shadow mask 6 of the present invention by forming electron beam hole 60, it constitutes colored selecting hole with etching mode in this complex gradient alloy sheets.These electron beam holes 60 have examples of dot shaped, and it has determined big diameter in phosphor screen one side, have determined little diameter in electron gun one side.With the die forming mode shadow mask 6 that forms electron beam hole 60 is molded as a given mask shape, is welded to then on the mask-frame shown in Figure 27, pendulum spring 8 is installed to forms a mask structure on the mask-frame 7.

In the embodiment shown in fig. 1, the shape of electron beam hole 60 is formed the examples of dot shaped with sub-circular.But, the invention is not restricted to this configuration.That is to say, the electron beam hole shape is formed the approximate elongated slot shape of major axis along a direction (usually along the vertical shift direction), perhaps form along the continuous seam shape (wire shaped) of a direction (usually along the vertical shift direction) and also can realize the present invention.

Adopt the shadow mask of complex gradient alloy sheets, and adopt this shadow mask to be assembled into color cathode ray tube as this embodiment of material for shadow mask, can access routine techniques the advantage that can not obtain.

Because the complex gradient alloy sheets does not contain the expensive metal element as cobalt, and, compare, can under low cost, produce the complex gradient alloy sheets by material cost and conventional invar material because can in second composite portion, adopt not nickeliferous material.

Because the complex gradient alloy sheets does not contain the cobalt with good corrosion energy, can improve the etching speed when forming electron beam hole, thereby can reduce the manufacturing cost of shadow mask.

Owing between first composite portion and second composite portion, there is the concentration ratio of alloying element in the complex gradient alloy sheets, can be with optimum shape etching electron beam hole, thus can form electron beam hole with uniform cross-section shape.

Because the stress distribution that produces changes gradually, can not act on very steep load to alloy sheets in alloy sheets when die forming complex gradient alloy sheets.Therefore, compare with conventional invar material, the intensity of complex gradient alloy sheets material can increase by 5 to 10 times.

Because can wholely reduce nickel content, increase permeability and reduced coercive force, can improve magnetic characteristic and raising protective benefits thus to earth magnetism.

Can improve its intensity because form the material for shadow mask of thin plate, can reduce by the generation (thermal expansion of shadow mask curved surface) of electron beam to caused part of the bump on shadow mask surface with holes or part protuberance.

Fig. 3 makes the explanation view that complex gradient alloy sheets method is given an example, and plate has constituted the material for shadow mask that is used for color cathode ray tube of the present invention.Here, the situation that the first composite portion 6A is formed by invar material (nickel-ferro alloy that contains the 36wt% nickel of having an appointment) and the second composite portion 6B is formed by the stainless steel that contains the 16wt% nickel of having an appointment has been described.

In Fig. 3, numbering 6AA has represented the molten material of invar material, and numbering 6BA has represented to contain the stainless steel molten material of 16wt% nickel of having an appointment.They are by rolling wheel PR1, and PR1 ' pulls into the hot plate bar, and adopt rolling wheel PR2 to bear hot roll extrusion in several steps, thereby they are fused into one.

In this hot rolling step, at invar material 6A with contain and form an alloy-layer between the stainless steel material 6B of the 16wt% nickel of having an appointment, can produce a complex gradient alloy sheets with concentration gradient thus, wherein nickel content reduces to another surface of veneer body gradually from a surface of veneer body.

After this, the complex gradient alloy sheets is subjected to adopting the cold rolling of rolling wheel PR3 in several steps, thereby obtains having the panel material as the desired thickness of material for shadow mask.

Fig. 4 is a perspective view, and the complex gradient alloy sheets structure that obtains in manufacturing process shown in Figure 3 has been described.Fig. 4 has represented the state similar in appearance to Fig. 1, wherein changes in the cross section nickel content between the surface and another surface gradually.Here, adopt the mode identical with state shown in Figure 1, the concentration of nickel element is represented with the dense degree of " * ".

Fig. 5 A and Fig. 5 B have represented the CONCENTRATION DISTRIBUTION of nickel in the complex gradient alloy sheets shown in Figure 4, and wherein Fig. 5 A has represented the distribution curve of nickel concentration, and Fig. 5 B is the schematic sectional view of the complex gradient alloy sheets of key diagram 5A.Shown in Fig. 5 A, nickel content in a surfaces A side of complex gradient alloy sheets is 36wt%, it just in time is an invar material nickel content, and the nickel content of the surperficial B side of another of complex gradient alloy sheets is 16%, and it just in time is the stainless nickel content that contains the 16wt% nickel of having an appointment.Between surfaces A and surperficial B, nickel content reduces to 16wt% gradually from 36wt%.The shape of nickel concentration distribution curve shown in Fig. 5 A is along with the rolling speed of thickness, temperature and rapidoprint, and other conditions when hot roll extrusion and cold rolling and changing.

Fig. 6 is a schematic sectional view, has illustrated that the internal stress of the complex gradient alloy sheets of this embodiment distributes.For example, when pressure that arrow P shown in Fig. 6 is represented affacts on the complex gradient alloy sheets of making in a manner described, outwards produce the tension stress that arrow SR represents in surfaces A one side from the pressure application point, produce the compression that arrow P R represents along inside compression direction in surperficial B one side.Reduce continuously corresponding to the distribution of nickel element shown in Fig. 5 A in these tension stresss SR and the compression PR zone between surfaces A and surperficial B, on approximate centre position, become 0.

At this moment, for the cross section of plate, stress tapers to compression PR from tension stress SR, the distribution near symmetrical of related stress SR and PR.Therefore, the complex gradient alloy sheets has the function that absorbs external impact.

Therefore, when this complex gradient alloy sheets was used as material for shadow mask, in the die forming that carries out after forming electron beam hole, the relative position between surfaces A and surperficial B is not skew almost, thereby the shape of electron beam hole almost is not out of shape.

When this complex gradient alloy sheets is used as material for shadow mask, be easy to the shadow mask curved surface of small curve that is shaped, thus the shadow mask of the small curve that might be shaped, it is corresponding to making the panel inner surface that is similar to the plane.

Zone for having concentration gradient from a surface to another surface in the veneer body of making at above-mentioned alloying element preferably forms this zone along whole shadow mask.But, can form this zone corresponding to the applying portion ground of color cathode ray tube.

For example, corresponding to the thermal characteristics of the mechanical property of anti-external impact of shadow mask and so on and the anti-electron beam hits of shadow mask and so on, can be from district AR with holes shown in Figure 2, peripheral part 61 (skirt section) and the concentration gradient zone that surrounds a zone formation alloying element of selecting the neighboring part (non-district with holes) of shadow mask 6 district AR with holes.

Fig. 7 A is the shadow mask illustrative view that is formed by the invar material as comparative example of the present invention, Fig. 7 B is the surface plate illustrative view with deep camber inner surface, and Fig. 7 C be when shadow mask is mounted on the panel on panel the illustrative view of the actual shadow mask image of seeing.

Fig. 7 A has represented a district with holes of shadow mask, and it is molded to be shaped and is such shape: have radius of curvature R x for 1600mm along level (along major axis) direction, have radius of curvature R y for 1300mm along vertical (along minor axis) direction.Fig. 7 B has represented an effective screen area of panel, and panel has the approximate flat outer surface and the inner surface of deep camber.Effective screen area hereto, along the corner part thickness T r of tube axial direction set for significantly greater than along the core thickness T c of tube axial direction (Tr＞＞Tc).At this moment, suppose that turning (along the end of diagonal) and the wall thickness difference (Tr-Tc) between the center at the effective screen of plate is diagonal wedge shape amount Wr, then the ratio Wr/Tc between wedge shape amount Wr and face plate center wall thickness T c is set at and is not less than 1.2.

For the shadow mask of die forming, shadow mask be shown as when a position slave plate off-centring on the shadow mask recessed more to plate when periphery screen, shown in Fig. 7 C.Then, for direction of observation, screen center's projection, thus see the image of somewhat a flat sensation.

Fig. 8 A is the shadow mask illustrative view that forms the periphery shape, Fig. 8 B is the surface plate illustrative view that only has curvature on inner surface along horizontal direction, and Fig. 8 C be when shadow mask is mounted on the panel on panel the illustrative view of the actual shadow mask image of seeing.

Fig. 8 A has represented a district with holes (a so-called wire colour selection electrode) of shadow mask, its such shape that is formed: have radius of curvature R x along level (along major axis) direction, have radius of curvature R y for infinitary value (∞) along vertical (along minor axis) direction for 2000mm.Fig. 8 B has represented an effective screen area of panel, panel have approximate flat outer surface and only along continuous straight runs the inner surface of curvature is arranged.Effective screen area hereto, along the corner part thickness T r of tube axial direction set for significantly greater than along the core thickness T c of tube axial direction (Tr＞＞Tc).At this moment, be set at along the wedge shape amount Wr of diagonal and the ratio Wr/Tc between the face plate center wall thickness T c and be not less than 1.0.

The shadow mask that is formed on the periphery shape has constituted a so-called pulling force shadow mask, along steering handle tension shown in Fig. 6 A to shadow mask.Be difficult to make shadow mask to have along the curvature of tension direction.Therefore, the inner surface of panel also has an approximate unlimited radius of curvature with respect to shadow mask tension direction.That is to say that the inner surface of panel vertically is essentially straight line.

Therefore, owing to constitute the refraction of the glass material of panel, the face plate center part spill that vertically is bent in sight is shown in Fig. 8 C.

Fig. 9 A is the shadow mask illustrative view that the material for shadow mask of this embodiment forms, Fig. 9 B is the surface plate illustrative view with small curve inner surface, and Fig. 9 C be when shadow mask is mounted on the panel on panel the illustrative view of the actual shadow mask image of seeing.

Fig. 9 A has represented a district with holes of the shadow mask of die forming, has mean radius of curvature Rx for 5000mm along level (along major axis) direction, has mean radius of curvature Ry for 4000mm along vertical (along minor axis) direction.Fig. 9 B has represented an effective screen area of panel, and panel has approximate flat outer surface and the curvature inner surface less than curvature shown in Fig. 7 B.Effective screen area is hereto set the core thickness T c that is a bit larger tham along tube axial direction (Tr＞Tc) for along the corner part thickness T r of tube axial direction.

Owing to the structure of this embodiment is provided, can have realized first that the satisfied shadow mask that makes of design of cathode ray tube optically is flat condition.That is to say that there is big actual strength in the shadow mask of this embodiment, the material of shadow mask has bimetallism, thereby shadow mask itself has the function of revising protuberance.Therefore, adopt mold pressing, might be configured as flat substantially shape to shadow mask, wherein be set at respectively and be not less than 3000mm along the mean radius of curvature Rx of level (along major axis) direction with along the mean radius of curvature Ry of vertical (along minor axis) direction.

Therefore, can reduce between the corner part thickness T r of panel shown in Fig. 9 B and the core thickness T c poor (turning wedge shape amount Wr), thereby the optical distance LcTc of the optical distance LrTr of corner part thickness T r and core thickness T c becomes basic identical.Therefore, descried image also becomes basic for flat, shown in Fig. 9 C.At this moment, the ratio Wr/Tr between turning wedge shape amount Wr and plate core wall thickness T r is set at and is not more than 0.8.

In addition, because can reduce the thickness of panel periphery part, image can easily obtain high brightness, thereby can improve the uniformity of brightness on the whole screen.

In addition, when the material for shadow mask of this embodiment is used for pulling force shadow mask shown in Fig. 8 A, can form curved surface and make the radius of curvature of along continuous straight runs increase, thereby the panel inner surface radius of curvature of along continuous straight runs also can increases.Therefore, construct same way as, can reduce the thickness of panel periphery part, thereby can improve the light characteristic of display screen with shown in Fig. 9 B.

In addition, for the pulling force shadow mask shown in Fig. 8 A, because colored selecting hole forms as the lines that extend continuously along a direction, have such situation: the wire grid that connects the colored selecting hole of wire is owing to impact and so on is vibrated.Therefore, in order to prevent this vibration, a filament is installed on the curved surface of pulling force shadow mask along major axis (X-axis).But,,, do not need to install especially filament and prevent vibration because the strength of materials of complex gradient alloy material obviously is better than conventional invar material because the pulling force shadow mask has been adopted complex gradient alloy material of the present invention.

As mentioned above, it is flat substantially that the mold pressing shadow mask is become, thereby can make the inner surface of panel also carry out suitable design for putting down substantially.Therefore, might reduce the reverberation on the plate inner surface that causes by wall thickness difference between plate core shown in Fig. 7 B and the peripheral part, and need be such as the antireflection device the inner surface filter membrane.In addition, can plate weight be lightened and the manufacturing cost that can reduce color cathode ray tube because make the inner surface of plate become basic putting down.

In addition, also for the color cathode ray tube that adopts so-called pulling force shadow mask, along a direction (usually vertically) tension on shadow mask, can increase along interior surface curvature radius perpendicular to the direction of a direction of the used panel of the present invention (along continuous straight runs usually), thereby can make the wall thickness attenuation of plate peripheral part, the reverberation that can suppress the plate inner surface thus can make plate weight lighten, and the manufacturing cost that can reduce color cathode ray tube.

In addition, the mold pressing shadow mask of setting this embodiment shown in Fig. 9 A is not less than 1000mm along minor axis (Y-axis) mean radius of curvature Ry, replace the pulling force shadow mask, can be used for such panel to the mold pressing shadow mask of this embodiment: it has the inner surface shown in Fig. 8 B that forms the periphery shape, and has increased the radius of curvature of its inner surface along major axis (X-axis) direction.

In addition, the material for shadow mask of this embodiment is formed by the complex gradient alloy sheets, and the complex gradient alloy sheets itself has the function of bimetallism.This feasible design can be revised the part protuberance of shadow mask curved surface, for example, because window scheme shows the local eminence that causes.

Conventional mask structure adopts the pendulum spring that is installed on the mask-frame to revise because the electron beam bump causes the protuberance and because the mask-frame thermal expansion that room temperature raises and causes of shadow mask curved surface.In this embodiment, because the function of the bimetallism of shadow mask itself, shadow mask itself just can be revised protuberance.Therefore, only the correction of mask-frame thermal expansion just is enough to the design of regulation pendulum spring, thereby degree is born in the design that can improve whole mask structure.The result is, the color cathode ray tube with high brightness and high definition might be provided, and it also can be worked in high Current Zone, and it is impossible revising protuberance in the usual way in this zone.

Though for the situation that adopts nickel-ferro alloy (it adopts iron as base material and the nickel that comprises as alloying element) as the complex gradient alloy sheets this embodiment has been described, the complex gradient alloy sheets is not limited to this alloy material.That is to say, adopt ferroalloy materials, the various types of stainless steel that contains chromium or nickel and chromium, the ferroalloy that contains other alloying elements, can finish this embodiment with the same manner.

In the above-described embodiments, changed the content of same alloy element (for example, nickel) for first composite portion and second composite portion.But, the invention is not restricted to this structure.That is to say, the complex gradient alloy sheets can constitute like this: adopt different alloying elements respectively in first composite portion and second composite portion, wherein reduce the alloying element content first composite portion gradually to another surface of plate body from surface of plate body, the alloying element content second composite portion is reduced on surface gradually from another surface of plate body to plate body.For example, even adopt nickel, can access advantageous effects similar in appearance to the foregoing description as the alloying element of first composite portion with when adopting silicon as the alloying element of second composite portion.

Figure 10 is a schematic sectional view, and an example of the whole structure of color cathode ray tube of the present invention has been described.This color cathode ray tube comprises a shell that vacuumizes, and shell has one and is coated with neck 2 and approximate funnel shaped glass neck 3 that is connected with neck 2 with plate 1 that electron gun 11 is housed with 1, one of the plate (panel) of multicolour fluorophor at inner surface.

Tri-color phosphor 4 is coated on the inner surface of plate 1, installs the shadow mask 6 with a large amount of colored selecting holes near fluorophor 4.Numbering 5 expression mask structures.The shadow mask 6 that constitutes mask structure 5 is formed and is fixed on the mask-frame 7 with welding manner by complex gradient alloy sheets (wherein having formed a large amount of electron beam holes that formed by etching complex gradient alloy sheets).

With big radius of curvature along continuous straight runs and the crooked shadow mask 6 of vertical direction.Suppose that a district approximate rectangular with holes minor axis (Y-axis: the direction of arrow Y) in the drawings perpendicular to shadow mask 6 and an axle by district center Om with holes are as Z axle (tubular axis), and in the district with holes of shadow mask 6 arbitrfary point (x, y) slippage that goes up from district center Om with holes along Z-direction is Zm, and then the curved shape of shadow mask 6 can usually be determined by following equation:

Zm＝A1x ²+A2x ⁴+A3y ²+A4y ⁴+A5x ²y ²+A6x ²y ⁴+A7x ⁴y ²+A8x ⁴y ⁴

(A1 to A8: coefficient)

Then, the coefficient of determining A1 to A8 in the equation just can access desirable curved shape.

Determine above-mentioned curved shape though get shadow mask 6 for example, can determine the curved shape of effective screen area in the same manner.

The curved surface of above-mentioned definite The Representation Equation is an aspherical shape in many situations, thereby its radius of curvature is different with the optional position of curved surface.Therefore, suppose the mean radius of curvature of this curvature, can determine the curvature (radius of curvature) of shadow mask by following equation for describing among Fig. 9 A.

Ry＝(Zv ²+V ²)/2Zv

Wherein Ry represents the mean radius of curvature (mm) along district with holes minor axis (Y-axis), V represent from district center Om with holes to along the Y-axis end along distance (mm) perpendicular to Z-direction, and Zv be illustrated in district center Om with holes and along between the Y-axis end along the slippage (mm) of Z-direction.

Though the minor axis (Y-axis) along shadow mask district with holes is determined above-mentioned mean radius of curvature, can determine mean radius of curvature along major axis (X-axis) or along diagonal in the same manner.In addition, can determine mean radius of curvature to effective screen area of plate 1 in the same manner.

An Antimagnetic hood 10 is fixed on electron gun one side of mask-frame 7, and mask-frame 7 is hung by stud pin 9 and fixes, and adopts pendulum spring 8 that the mode of stud pin 9 with projection is installed on the inwall in plate 1 skirt section.

A deflecting coil 13 is installed in neck one side of glass neck 3 from the outside, is offset three electron beam B that radiate from electron gun 11 along horizontal direction and vertical direction (direction of arrow Y among the figure), thereby is formed on the image on the phosphor screen 4.In the drawings, numbering 12 one of expression are used for the magnetic correcting device of colour purity correction, focusing correction etc., and number explosion-proof band of 14 expressions.

Employing has the color cathode ray tube of this structure, and the coloured image that can access high brightness and high definition shows, it can suppress to swell caused color blooming by the shadow mask curved surface.

Figure 11 is a schematic sectional view, and another example of the whole structure of color cathode ray tube of the present invention has been described.In the drawings, identical with numbering among Figure 10 numbering is corresponding to same function part.This color cathode ray tube comprises a shell that vacuumizes, and shell has one and is coated with the plate 1 with the multicolour fluorophor, a neck 2 and the approximate funnel shaped glass neck 3 that is connected with neck 2 with plate 1 that electron gun 11 is housed at inner surface.But in this embodiment, the inner surface of plate 1 has the vertically infinitely great radius of curvature of (direction of arrow Y among the figure) of the larger radius of curvature of an along continuous straight runs and.

The shadow mask 6 that formation is installed in colour selection electrode in the color cathode ray tube has the larger radius of curvature of an along continuous straight runs, and have one more much bigger or be infinitely-great radius of curvature vertically than along continuous straight runs radius of curvature.

When being applied pulling force, shadow mask 6 is fixed on the mask-frame 7.But, can keep shape by self and the following shadow mask 6 of state that is not applied pulling force is fixed on the mask-frame 7 at shadow mask 6.Even keep shape by self and the following shadow mask 6 of state that is not applied pulling force is fixed on the mask-frame 7 at shadow mask 6, the bimetallic function of shadow mask can be revised protuberance, and can reduce color and blur and so on phenomenon.

Employing has the color cathode ray tube of this structure, and the coloured image that can access high brightness and high definition shows that it can suppress the color blooming that surface elevation causes.

As having illustrated so far, according to particular configuration of the present invention, the shadow mask of formation colour selection electrode does not comprise the expensive metal element as cobalt and so on, perhaps might adopt the material that does not comprise nickel and so in a surperficial side.Therefore, compare and to reduce cost with conventional invar material, can improve the etching performance that forms electron beam hole, and can be etched into suitably shape to electron beam hole, thereby can form electron beam hole with uniform cross-section shape according to the ratio of alloy zone in the complex gradient alloy sheets.

In addition, because whole nickel content can reduce, improved magnetic characteristic, improved protective benefits to earth magnetism, increased the material for shadow mask intensity that thin plate is made greatly, thereby can reduce the generation of local eminence, the color cathode ray tube of high brightness and high definition might be provided thus, have thin panel simultaneously.

Claims

1. one kind has a color cathode ray tube that vacuumizes a shell and a shadow mask, shell comprises a glass neck that is coated with plate with the broken colour fluorophor, neck that electron gun is housed and connecting plate and neck at inner surface, shadow mask is installed near the fluorophor that is coated on the plate inner surface, and has a district with holes that forms by a large amount of colored selecting holes, wherein

The plate body that the material of formation shadow mask is made by the iron material that contains a kind of alloying element forms, plate body is a complex gradient alloy sheets with alloy element concentration gradient, reduces alloying element from the surface of fluorophor one side of plate body continuously to the surface of electron gun one side.

2. color cathode ray tube according to claim 1, wherein the district with holes of shadow mask is along its major axis, and mean radius of curvature is set at and is not more than 3000mm.

3. color cathode ray tube according to claim 1, wherein alloying element is a nickel.

4. color cathode ray tube according to claim 3 wherein is set at the nickel content of the plate body near surface of fluorophor one side and is not more than 45wt%, and is set at the nickel content of the plate body near surface of electron gun one side and is not more than 0wt%.

5. color cathode ray tube according to claim 4 wherein is set at the nickel content of the plate body near surface of fluorophor one side and is not more than 36wt%, and is set at the nickel content of the plate body near surface of electron gun one side and is not more than 16wt%.

6. color cathode ray tube according to claim 1, wherein alloying element is a chromium.

7. color cathode ray tube according to claim 1, wherein alloying element is nickel and chromium.

8. the color cathode ray tube according to claim 1 wherein is formed on the colored selecting hole that forms in the shadow mask with dot matrix way.

9. the color cathode ray tube according to claim 1 wherein is formed on the colored selecting hole that forms in the shadow mask as the many continuous lines that extend along a direction.

10. color cathode ray tube according to claim 1, the colored selecting hole that wherein forms in shadow mask are formed many slits that its major axis extends along a direction.

11. one kind has a color cathode ray tube that vacuumizes a shell and a shadow mask, shell comprises a glass neck that is coated with plate with the broken colour fluorophor, neck that electron gun is housed and connecting plate and neck at inner surface, shadow mask is installed near the fluorophor that is coated on the plate inner surface, and has a district with holes that forms by a large amount of colored selecting holes, wherein

The veneer body that the material of formation shadow mask is made by the iron material that contains a kind of alloying element forms, and compares with the veneer surface of fluorophor one side, and the content that is included in alloying element in the veneer body on the veneer surface of electron gun one side is set seldom.

12. the color cathode ray tube according to claim 11, wherein the district with holes of shadow mask is along its major axis, and mean radius of curvature is set at and is not more than 3000mm.

13. the color cathode ray tube according to claim 11, wherein alloying element is a nickel.

14. the color cathode ray tube according to claim 13, wherein near the nickel content the veneer surface of fluorophor one side is set at and is not more than 45wt%, and near the nickel content the veneer surface of electron gun one side is set at and is not more than 0wt%.

15. the color cathode ray tube according to claim 14, wherein near the nickel content the veneer surface of fluorophor one side is set at and is not more than 36wt%, and near the nickel content the veneer surface of electron gun one side is set at and is not more than 16wt%.

16. the color cathode ray tube according to claim 11, wherein alloying element is a chromium.

17. the color cathode ray tube according to claim 11, wherein alloying element is nickel and chromium.

18. one kind has a color cathode ray tube that vacuumizes a shell and a shadow mask, shell comprises a glass neck that is coated with plate with the broken colour fluorophor, neck that electron gun is housed and connecting plate and neck at inner surface, shadow mask is installed near being coated in the fluorophor on the plate inner surface and having a large amount of colored selecting holes, wherein

The veneer body that the material of formation shadow mask is made by the iron material that contains a kind of alloying element forms, and is included in the alloying element difference in the veneer body between surface of veneer body and another surface.

19. the color cathode ray tube according to claim 18, wherein the veneer body surface has constituted fluorophor one side, and another surface of veneer body has constituted electron gun one side.

20. the color cathode ray tube according to claim 18, the alloying element that wherein is included in surface of veneer body is a nickel, and the alloying element that is included in another surface of veneer body is a silicon.