JP3108468B2 - Display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device and, more particularly, to a display device having a flat face plate and dividing a surface of a screen formed on the face plate into a plurality of small areas by an electron beam. .

[0002]

2. Description of the Related Art A cathode ray tube is a typical display device which displays an image on a phosphor screen by scanning an electron beam in a vacuum envelope. In recent years, various studies have been made to meet the demand for a high-resolution picture tube having a large screen for high-definition broadcasting or associated with it. In order to achieve higher resolution of the picture tube, the electron beam spot diameter on the screen surface must be reduced. On the other hand, improvements in the electrode structure of the electron gun, which is an electron beam generating source, and enlargement and extension of the diameter of the electron gun itself have been made, but they are still insufficient. The biggest factor is that the distance between the electron gun and the screen surface becomes longer as the tube becomes larger, and the magnification of the electron lens becomes too large. That is, it is important to shorten the distance between the electron gun and the screen in order to realize high resolution. In this case, the method based on wide-angle deflection causes an increase in the magnification difference between the center and the periphery of the screen, which is not an appropriate measure.

For this reason, a method of displaying a large screen with high resolution by arranging a plurality of independent small picture tubes conventionally has been proposed.
JP-A-48-90428, JP-A-49-21019, Japanese Utility Model
It is proposed in JP-A-53-117130. This type of method is effective for a large screen display with a large number of divisions placed outdoors, etc., but in the case of a medium-sized large screen display with a display screen size of about 40 inches, the joint of the screen for each area is Obviously, the reproduced screen is difficult to see. In particular,
When used as a graphic display terminal for computer aided design (CAD), it is needless to say that having a joint on the display screen is a fatal defect. Therefore, a structure integrating the screen portions of a plurality of independent picture tubes is also disclosed in U.S. Pat.
No. 1,706, Japanese Utility Model Publication No. 39-25641, Japanese Patent Publication No. 42-4928
And Japanese Patent Application Laid-Open No. Sho 50-17167.

As shown in FIG. 13, a picture tube 1 having an integrated screen structure includes a face plate 3 having a screen surface 2, a rear plate 4 opposed thereto, and a plurality of funnels 5 connected to the rear plate 4. And a vacuum envelope consisting of a neck 6 continuing from the funnel 5.
The face plate 3 is at least glass, and the rear plate 4 is glass or metal. In such a structure, when the screen surface 2 becomes large, the face plate 3 and the rear plate 4 must be considerably thick in order to support the vacuum, and a large curvature must be provided in the tube axis direction. For this reason, the entire envelope becomes extremely heavy, and the screen surface 2 has a curvature in the tube axis direction and becomes very difficult to see. Further, the distance between the screen surface 2 and the electron gun 7 sealed in the neck 6 becomes large, which is not preferable in terms of the magnification of the electron lens.

When a metal is used for the rear plate, a method is known in which a reinforcing plate (beam) is provided on a relatively thin metal plate in order to maintain sufficient strength against atmospheric pressure and reduce the weight. .

The rear plate using this metal is very effective when there is no projection member such as a funnel or a neck on the back surface of the display device. In addition, the funnel and the neck are arranged on the back surface and the rear plate is internally provided. When an electron gun emits an electron beam and applies it to the structure of the envelope of a display device such as a cathode ray tube that scans the screen surface by dividing it into multiple areas, the rear plate, which was conventionally complicated, can be simplified. Shape. However, in a cathode ray tube in which a funnel and a neck are connected to the rear plate and the fluorescent screen is divided and scanned, the arrangement position of the electron gun, which is the emission position of the electron beam, and the position of the fluorescent screen must be precisely adjusted to a predetermined position. Since the metal rear plate is more easily deformed by the atmospheric pressure than the glass rear plate, the position of the electron gun changes due to the deformation of the metal rear plate, and the electron beam cannot be fired from a predetermined position in a predetermined direction, resulting in display. Significantly degrades screen quality. Therefore, the metal rear plate is effective only for a display device that does not affect the internal structure or the electron beam trajectory even if the rear plate is slightly deformed due to the atmospheric pressure, such as a cathode ray tube in which a funnel and a neck are connected to the rear plate. When applied to a simple structure, the amount of deformation must be calculated in advance and the electron gun must be arranged at a predetermined position after the deformation, which is not preferable in the design, manufacture, and management of the cathode ray tube.

Further, the inside of the rear plate (the inside of the envelope)
In a cathode ray tube, which becomes a high potential equipotential space, it is necessary to provide an electrically insulating structure so that the high potential is not exposed to the outside. In a cathode ray tube in which a funnel and a neck are connected to the rear plate, this potential is Is extremely high, which is extremely undesirable for practical use.

Further, the rear plate 4 corresponding to the funnel of the conventional cathode ray tube shown in FIG. 13 cannot have a structure including a sudden change in shape from the viewpoint of moldability of glass or strength with respect to the atmosphere. It is inevitable that the shape changes gradually. Therefore, it is extremely difficult to make the shape of the portion on which the deflection device is mounted substantially equal to the deflection area of the electron beam, and to reduce the thickness of the glass of the deflection device mounting portion, and use a small deflection device with low deflection power. It is impossible.

Further, even when a metal plate is used for the rear plate, the inner surface of the funnel at the portion where the deflection yoke is mounted is close to the actual electron beam trajectory region, and the funnel is formed thin, the metal rear adjacent to the deflection device is formed. Loss due to eddy current or the like generated in the plate is inevitable, resulting in an increase in deflection power. Further, when a metal rear plate is used, the structure is such that a metal plate is arranged between adjacent deflection devices, and the magnetic fields of the deflection devices easily interfere with each other, and it is extremely difficult to form an appropriate magnetic field distribution.

Generally, for vacuum envelopes with flat faceplates, the use of supports to support large area faceplates is well known in connection with vacuumed solar collectors. Japanese Patent Application Laid-Open Nos. Sho 56-106353, 62-272432, 62-285335, 63-128532, and 63-128532 also describe flat display devices using these supports. JP-A-48-90183,
Many proposals have been made, such as JP-A-64-10553 and JP-A-1-117251.

As shown in FIGS. 14 and 15, as a method for supporting the atmospheric pressure applied to a flat envelope 10 whose inside is evacuated, there is a long plate-like support means 11 or a needle-like support means. The long plate-like support means 11 is to prevent the load of the atmospheric pressure from being concentrated at one point by supporting the screen surface 12 with a large contact area, but the inventor has determined that these support means 11 are based on various experimental results. It has been found that it has various problems.

First, there is a problem of processing accuracy of the support means.
In this method, as shown in FIG. 16, it is necessary to machine the end portion 11a of the screen surface abutting along the black stripe 12a into a knife edge shape, and furthermore, the distance between the face plate and the rear plate and the length of the support means (height). Need to be exactly the same. For this processing, for example, if the length of the knife edge portion is about 30 mm or less, it can be processed practically (mass production), but if it is longer than this, special finishing processing is required and low cost It is impossible to make. Second, there is the problem of the strength of the plate member. In the case of a plate-shaped member, the strength is strong when a load is applied in a direction parallel to the surface of the plate material, but when a load in a direction inclined to the surface is applied, it is easily deformed and applied to other adjacent support means. Excessive load is applied. Third is a method of attaching the plate member. Since the plate-like member cannot stand on its own, a member for erecting the plate-like member on the rear panel or the like or a fixing jig is required for welding in the case of welding. Fourth is the problem of warpage. The plate-like member is resistant to in-plane deformation, but is easily deformed in directions other than in-plane, and as shown in FIG. 17, easily deforms 11b at the time of mounting or during a heating process. Fifth, there is a problem of contact with the glass plate. Since a normal sheet glass is manufactured by a float method, it is impossible to make the thickness of the sheet glass completely uniform over the entire surface. In this distribution of plate thickness, for example, there is no sharp difference in plate thickness in a relatively narrow portion of about 50 mm, but the difference in plate thickness is 0.05 in a relatively wide portion of about 200 mm.
mm to 0.1 mm. That is, even if the plate-like supporting means is processed with high accuracy and assembled, it does not always come into complete contact with the plate glass of the face plate.

Next, problems concerning the needle-shaped support means will be described. First is the number of issues needed to support atmospheric pressure. The plate-like support means has a relatively large contact area with the glass, whereas the needle-like support means is extremely small. To reduce the load on each support means, an extremely large number of needle-like support means are required. Specifically, they must be arranged at a pitch of 10 mm or less, and 1000 or more needle-like supporting means are required to support the atmospheric pressure applied to the sheet glass whose diagonal size of the screen is equivalent to 20 inches. Second, there is the problem of processing accuracy. In this method, it is necessary to process the tip into a needle shape. In general, the method of processing a wire into a needle shape can be easily performed by cylindrical polishing or the like, but it is difficult to accurately match the center axis of the wire with the needle-shaped tip portion after processing, and the wire is often processed eccentrically. . Third, there is the problem of the strength of the needle-shaped member. As in the case of the plate-like support means, it is strong against the load in the axial direction of the wire, but extremely weak against the load in the direction inclined to the axis, easily deformed and excessive load is applied to other adjacent support means. Join. Fourth is a method of attaching the needle-shaped member. As in the case of the plate-shaped support means, the thin needle-shaped member cannot stand on its own, so a member for standing upright with respect to the rear panel or a fixing jig in the case of welding is required to attach the needle-shaped member to the rear panel etc. It is.

As described above, the plate-like or needle-like supporting means is not practically preferable from the viewpoint of structure, production as a part, assembly, or cost. Further, many of the flat cathode ray tubes proposed so far include, as shown in FIG. 15, a large number of linear cathodes 13 and a large number of control electrodes 14, acceleration electrodes 15, deflection electrodes 16, and the like. It is very complicated and has many problems in mass production, and it becomes extremely difficult to manufacture a large screen surface. In addition, the large number of these supporting members and internal electrodes causes a problem of occlusion gas of such members, and greatly deteriorates the life characteristics of a cathode ray tube, which is extremely undesirable in practical use.

[0015]

As described above, a display device such as a cathode ray tube has a high resolution, a short depth, an easy-to-view screen, a simple structure, a high practicality and an industrial value. When trying to get a high cathode ray tube,
In the prior art, there were various problems and it was difficult to achieve. The present invention has been made to solve the problems of the related art, and an object of the present invention is to provide a display device which is highly practical and has high industrial value.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a first plate having at least a substantially rectangular shape, and a first plate from a periphery of the first plate. A vacuum envelope including a side wall extending in a direction perpendicular to the first plate, and a flat second plate disposed substantially parallel to the first plate, and covered on an inner surface of the first plate. A phosphor screen attached thereto, a plurality of electron sources for generating an electron beam for dividing and scanning the phosphor screen into a plurality of small areas, and provided between the first plate and the second plate. At least a plurality of support means for supporting these plates at a predetermined interval, wherein when the thickness of the first plate is t and the interval between the support means is P, the ratio t / P is 0.05 or more. It is characterized by.

Also, a substantially rectangular flat first plate, side walls extending from a peripheral portion of the first plate in a direction substantially perpendicular to the first plate, and opposing the first plate. And a substantially flat second
A vacuum envelope including a plate, a phosphor screen attached to the inner surface of the first plate, and a plurality of electron beams for generating an electron beam for scanning the phosphor screen in a plurality of small areas. An electron source, the first plate and the second
At least a plurality of support means provided between the plates and supporting the plates at a predetermined interval, and the first plate-side end of the support means has a wedge shape and has a longitudinal direction of the wedge-shaped end. The length is 2 to 30 mm.

Furthermore, a substantially rectangular flat first plate, side walls extending from a peripheral portion of the first plate in a direction substantially perpendicular to the first plate, and opposing the first plate. A second plate that is arranged substantially in parallel and provided with a plurality of apertures, and a plurality of plates that are provided between the first plate and the second plate and support the plates at predetermined intervals. And a vacuum envelope consisting of a funnel connected to each of the plurality of apertures of the second plate, and a neck extended from the funnel. The inner surface of the first plate A phosphor screen attached thereto; and an electron gun as an electron source sealed in each of the necks, wherein the phosphor screen is provided with a plurality of small areas by electron beams from the plurality of electron guns. Minute Is scanned, the plurality of supporting means on the division scanning of the boundary line is characterized by being located.

[0019]

According to the present invention, a plurality of independent screens are integrated into a structure, and this screen is formed on the inner surface of a glass face plate which is a flat first plate. The rear plate as the second plate to be formed is also flat, and a support means for supporting the atmospheric pressure is disposed between them. In addition, a plurality of electron sources for generating an electron beam are arranged to face the screen. The support means is disposed on the screen surface at a predetermined interval P. Assuming that the thickness of the face plate is t, by setting the ratio t / P to 0.05 or more, the thickness of the face plate can be minimized and the number of support means can be significantly reduced. For this reason, the weight of the display device is reduced, and the number of support means is small, so that the manufacture is extremely easy.

Also, since the face plate and the rear plate are flat and the distance between the electron source and the screen surface can be set to the minimum and the same, the magnification of the electron beam with the electron lens can be reduced and the spot on the screen surface can be reduced. Form small and high-resolution images. The depth is reduced, the weight can be reduced compared to the area of the screen surface, and an image that is easy to see on the screen surface is provided.

Further, in the present invention, the screen portions of a plurality of independent picture tubes are integrated, and this screen portion is formed on the inner surface of a flat face plate and the rear plate is flattened. The support means is arranged at. At this time, the first plate side end of the support means is formed in a wedge shape, and the length of the wedge-shaped end in the longitudinal direction is set to 2 mm to 30 mm so that the thickness of the face plate is made as thin as possible. The number can be significantly reduced. Therefore, the weight of the display device can be reduced, and the number of the support means is small, so that the manufacture is extremely easy.

Further, since the face plate and the rear plate are flat, the distance between the electron source and the screen surface can be set to the minimum and the same, so that the magnification of the electron lens can be reduced and the spot on the screen can be reduced. High resolution can be achieved. At the same time, the display device has a very short depth. Further, since the screen surface is flat, it is possible to provide an image which is extremely easy to see. Together with these advantages, it is possible to provide a display device which is highly practical and has high industrial value.

Further, in the present invention, the screen portions of a plurality of independent picture tubes are integrated into a structure, and this screen portion is formed on the inner surface of a flat face plate, and the rear plate is formed of a plurality of flat glass plates. A structure having openings is provided, and a support means for securing the interval between both plates against the atmospheric pressure is arranged between them. In addition, the funnel continues from the opening in the rear plate,
The neck portion is continuous from the funnel. By using the flat rear plate provided with the opening as described above, the supporting means can be arranged on a flat rear plate other than the opening, and a very simple structure can be obtained. it can. In addition, since the distance between each electron gun, which is an electron source, and the screen surface can be set to the minimum and the same, the magnification of the electron lens can be reduced, and the beam spot on the screen surface is reduced.
High resolution can be achieved. At the same time, the display device has a very short depth. Further, since the screen surface is flat, an image which is extremely easy to see can be provided. Furthermore, the structure is very simple, similar to the structure in which a plurality of ordinary picture tubes are arranged, and since the support means is provided, the face plate and the rear plate can be made thin, and the weight of the display device can be reduced. .

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings. (Example 1)

FIGS. 1 to 5 show a display device according to an embodiment of the present invention. FIG. 1 is a perspective view showing the entire structure, and FIGS. 2 and 3 are sectional views. The display device 20 includes a flat face plate 21, a side wall 22 around the face plate 21 and extending in a direction substantially perpendicular to the plate surface, a rear plate 23 facing the face plate 21, and a connection to the rear plate 23. Multiple funnels 24 and neck 25
An electron gun 26 as an electron source is sealed in the neck 25, and a deflecting device (not shown) is arranged near the electron gun 26. The face plate 21 is made of flat glass, and phosphors of one to three colors are applied to form a phosphor screen 30. By deflecting and scanning the screen surface with an electron beam emitted from each electron gun by a deflecting device, the phosphor is bombarded and illuminated, and a raster R of a small area is formed.
Draw 1, R2, R3 ..., R20. The rasters of these small areas are connected by signals applied to electron guns and deflection devices,
Project one large raster over the entire screen. The rear plate 23 is also made of flat glass, and has an opening 27 at a predetermined position. The funnel 24 is joined to the opening 27. A support rod 31 as shown in FIG. 4 is fixed as a support means near the opening 27. The tip 31a is wedge-shaped, and the thin flat face plate 21 and the rear plate 23 are brought to atmospheric pressure. It is held at a predetermined interval in opposition. As shown in FIG. 5, the support rods 31 are arranged at respective intersections 32 on the boundary line of the raster of the small area of the small area screen.

As described above, a substantially rectangular flat face plate, side walls extending from a peripheral portion of the face plate in a direction substantially perpendicular to the face plate, and substantially at predetermined intervals facing the face plate. In a vacuum envelope including a rear plate that is arranged in parallel, a strong atmospheric pressure acts on the entire envelope. For this reason,
With a 20-inch faceplate size, more than one ton of force is applied to the entire surface. In order to support this atmospheric pressure, it is more stable if the number of the support means is increased. However, it is not preferable in terms of mass production, and it becomes difficult to process an occluded gas and the life characteristics are deteriorated.

Therefore, the inventors conducted a simulation described in detail below, and found that the distance between the thickness of the face plate of the display device having sufficient strength against the atmospheric pressure and the distance between the support means without deteriorating the image characteristics. A predetermined relationship was determined.
That is, when the thickness of the face plate is t and the interval between the support means is P, the ratio t / P may be set to 0.05 or more.

The present inventors have variously studied the proof stress of a flat glass face plate against atmospheric pressure from experiments using a rectangular vacuum device 40 having an inner dimension of 300 mm in length and 400 mm in width as shown in FIG. did. According to this result, the size equivalent to the 20-inch type, that is, the diagonal distance
In the case of glass of 500 mm, unless the thickness is 15 mm or more, the glass will break at atmospheric pressure in vacuum. When the vacuum pump 41 is operated to evacuate the space between the glass of the vacuum device 40 and the glass, the glass 50 curves from the mounting position 52 on the support frame 51 as shown in FIG. Cannot withstand atmospheric pressure. In a cathode ray tube with a glass face plate curved to a normal spherical surface, even if the central part is 12 to 13 mm thick, the peripheral part exceeds 20 mm thick, and the peripheral edge is tightened with a tension band to maximize the stress. Part is about 1000 [PSI]
(Pounds per square inch) or less to prevent envelope destruction. For this reason, it is necessary to make the glass thickness 12 to 13 mm or more without the support. Therefore, when one bar-shaped support 53 is disposed at the center as shown in FIG. 7B, the glass plate 50 for the face plate is distorted as shown. In this case, the plate thickness can withstand the atmospheric pressure at 10 mm or more. Next, as shown in FIG. 7 (c), when a total of nine support members 53 are planted at the center of the support member 53 and the support frame 51 at the center and at the same interval on the left and right, the deformation of the glass is further reduced, Glass with a thickness of 4.5-5 mm or more can withstand atmospheric pressure.

However, even if the number of supporting means is further increased, the thickness of the glass plate cannot be reduced proportionally, and the number of supporting means A (arranged at equal intervals) by the apparatus shown in FIG. As can be seen from FIG. 8 showing the relationship of the thickness t ₀ mm, the plate thickness of 2 mm was the limit that could withstand the atmospheric pressure. Then, as shown in FIG. 8, if the relationship between the number A of the support means and the glass thickness t is in the shaded region, it is possible to withstand the atmospheric pressure.

As shown in FIG. 7C, the face plate 30
When the thickness t is t and the interval between the supports 33 is P, if the ratio t / P is larger than a predetermined value, the amount of deformation 1 of the face plate is almost negligible, and there is no risk of breakage due to the deformation. When the ratio t / P is smaller than a predetermined value, the amount of deformation 1 of the face plate becomes large, causing breakage. In order to resist the internal strain of the glass, it is necessary to prevent the deformation from occurring so much, and it is necessary to secure a certain thickness of the glass. Table 1 shows the ratio t / P calculated from the experimental results in FIG. As is clear from Table 1, the ratio t / P needs to be 0.05 or more for the sheet glass to withstand the atmospheric pressure.

[0031]

[Table 1]

In the case of the above-described 20-inch size, when the screen is divided into five vertically and five horizontally divided areas, the number of intersections of each divided area is 16, and if the supporting means is arranged at each intersection, the number of supporting means becomes Becomes 16. In this case, since the screen size is about 400 mm in width and about 300 mm in height, one divided area is about 80 mm in width and about 60 mm in height, and the interval P between the supports is about 70 mm on average in the length and width. T for 4mm
/ P is 0.057, which indicates that the film sufficiently withstands atmospheric pressure.

This means that the face plate size is 40
In the case of inches, when the thickness of the face plate is 4 mm, the interval P between the support means may be 70 mm on average, so that the number of support means is 81. In addition, the distance P between the support means is twice as large.
If it is set to 140 mm, the number A of all support means may be 16 and
In this case, the glass thickness t is at least 7 mm. The selection of the glass thickness and the number of supports can be determined in consideration of the total weight of the cathode ray tube, its own weight with respect to the face plate area, and the impact resistance. That is, the weight reduction achieved by reducing the glass thickness of the face plate, the disadvantage of having to increase the number of support means, and conversely, the weight increase of the face plate by increasing the glass thickness, and furthermore, the atmospheric drag Not only that, it is important to ensure impact resistance.

In the embodiment shown in FIGS. 1 to 5, the aspect ratio is 3:
4. It has a 20-inch size face plate,
The screen is divided into five parts in the horizontal direction and four parts in the vertical direction. Therefore, there are twelve intersections, and the rod-shaped supports are arranged in this part, so that the number is twelve. Since the distance P between the supports is about 80 mm in the horizontal direction and about 75 mm in the vertical direction,
78mm pitch. Therefore, at a plate thickness of 4 mm, t /
P is 0.051, and even if the thickness of the glass face plate is set to 5 mm in consideration of safety, an envelope having a light weight and sufficient atmospheric pressure strength can be realized. Since the number of the supports is only 12, the production is simple, and the release of the occluded gas under vacuum can be neglected, so that the life of the cathode ray tube display device is not deteriorated.

In this embodiment, since the thickness of the face plate is 5 mm, the weight of the face plate is about
It is only 1.8 kg, and the weight of the face plate of the conventional pipe of the same size is considerably lighter than that of about 9 kg,
The weight of the entire display device is also significantly reduced.

As described above, according to the present invention, when a cathode ray tube having a flat glass face plate is formed, the thickness t of the face plate is set to 2 mm or more, and the distance P between the rod-shaped supports is set. Is set so that t / P becomes 0.05 or more, a stable and flat vacuum envelope can be secured. The number of supports is very small, which has a large effect on the production and life of the tube. Moreover, the weight of the cathode ray tube can be reduced, so that a flat cathode ray tube with high practicality can be easily produced. Become.

It is desirable to reduce the number of support means in terms of the operation of the tube, but since the peripheral edge of the face plate is supported by the side wall, the resistance against the atmospheric pressure is large.
The supporting means adjacent to the side wall is slightly thickened at the center of the face plate which is easily deformed at atmospheric pressure, slightly away from the side wall, whereby the number of supporting means can be reduced. If the thickness of the face plate is increased, the number of support means can be reduced.However, in consideration of the weight of the face plate or the weight of the cathode ray tube, the thickness is preferably as small as possible. Anything over 15mm is not practical. In addition, the production by the float method becomes difficult,
Productivity also worsens. Further, the effect of the present invention is remarkable when the thickness of the face plate is thinner than that of a conventional cathode ray tube having no support means, and it is preferable that the thickness is 10 mm or less. It is a target.

In a cathode ray tube in which a screen is divided and scanned by a plurality of electron guns as in this embodiment, it is necessary to arrange adjacent electron guns at a certain distance, and this interval (center axis of adjacent electron guns) is required. The distance (interval) depends on the structure of the electron gun, but cannot be less than 15 mm. When the support means is arranged at the intersection of the divided areas of the screen, the arrangement interval must be at least 15 mm or more. Therefore, in the case of the present embodiment, considering the range of the plate thickness, t
If the upper limit of / P exceeds 1.0, it is difficult to realize, and in this embodiment, the effect is remarkable at 0.67 or less, preferably at 0.33 or less.

Further, in the present embodiment, the structure of the support means is a rod-like shape having a wedge-shaped tip, but it may be a needle-shaped tip. However, since the internal strain is intensively increased in a portion of the glass where the needle-shaped portion contacts, it is not so preferable, and it is preferable that the tip that contacts the glass be linearly elongated. When the screen is formed of a stripe phosphor of three colors including a stripe-shaped black substance, the non-light-emitting portion of the support means generated on the screen can be made inconspicuous by disposing the tip of the support means on the black substance. However, the stripe width of the black material is at most 100 μm, and it is difficult to accurately adjust the tip of the support means on the black material as the linear length of the contact portion, that is, the length in the longitudinal direction becomes longer. Also, in consideration of the fact that the tip of the support means is deformed by the temperature change during operation and breaks the screen, the linear length of the tip of the support means is shortened without being integrated with the tip of the support adjacent in the length direction. Better.

Further, in this embodiment, the structure in which the funnel and the neck are connected to the rear plate and the electron gun is provided in the neck as shown in FIGS. 1 to 5 has been described. However, the present invention is limited to the above structure. Not something. That is, the present invention is applicable to any structure in which a support between two opposing flat plates is supported by a support means. For example, in the case of a display device combining a linear cathode and electrostatic deflection, the electron gun structure as in the above embodiment is applicable. Can further reduce the lower limit value of the distance between the support means, and as a result, the range of the value of the ratio t / P can be widened. In the present invention, the ratio t / P may be appropriately set according to the structure of the display device to which the ratio is to be applied. (Example 2)

Next, another embodiment of the present invention will be described for a case where the present invention is applied to a 20-inch display device. In this embodiment, the entire structure is the same as that of the first embodiment shown in FIGS. The distance between the face plate and the rear plate is 20 mm on the entire surface of the screen 30, and the length of the support means 31 shown in FIG. 9 is also 20 mm. The support means 31 is formed by machining the tip of a metal round bar having a diameter of 15 mm into a wedge shape.
31a has a width W of 0.05 mm and a length L in the longitudinal direction of the tip portion of 15 mm, which is the same as the diameter of the metal round bar. The wedge-shaped tip portion 31a abuts on the black stripe of the screen 30, and the width of the black stripe is 0.07 mm.

In this embodiment, the size of the phosphor screen 30 formed on the inner surface of the face plate 21 is about 400 mm × 3.
The atmospheric pressure applied to the screen is supported by twelve support means 31.

Next, the result of study of the stress distribution of the face plate when the atmospheric pressure is applied when the wedge-shaped tip portion 31a of the support means 31 which is the main part of this embodiment abuts on the face plate 21 will be described.

The strength when the atmospheric pressure is applied to the face plate depends on the first factor determined by the thickness of the face plate glass and the interval between the support means as described in the first embodiment and the support means to be described later. There is a second factor determined by the shape and size of the tip. In the former, the face plate is deformed by a relatively large area due to atmospheric pressure, and due to this deformation, stress in the compression direction is applied to the outer surface of the face plate,
A tensile stress is generated on the inner surface, and the inner surface is broken when the stress (tensile stress) exceeds a critical value.
On the other hand, the latter is a fracture caused by a tensile stress generated intensively in the glass near the tip of the support means when the face plate and the support means come into contact with each other.
In many cases, the deformation is caused by partial deformation of only one surface on the side (the inner surface side) where the support means abuts without large deformation of the entire glass. In order to prevent the latter destruction, it is desirable to increase the contact area between the glass and the support means and reduce the load per unit area to reduce the amount of partial deformation. As described above, it is difficult to increase the area of the tip of the support means due to various problems. The inventor of the present invention has found an efficient shape of the front end of the support means while minimizing the increase in the contact area of the front end of the support means.

The stress intensively generated on a part (one side) of the sheet glass is obtained by calculating the contour line (isostress line) of the maximum stress near the contact between the supporting means and the sheet glass by computer simulation using the finite element method. The state of concentration of stress can be determined based on the density of the contour lines.
Also, in this type of computer simulation, it is extremely difficult to accurately calculate the absolute value of the stress at the contact portion between the tip and the glass, and it is meaningless for evaluating the concentration and distribution of stress. Judgment was made from the stress distribution near the contact area (comparison of relative values). The state in which the glass breaks due to the concentration of stress means that high-value iso-stress lines are distributed at one point and at a dense pitch. In this case, the sheet glass has a certain length at the tip of the support means. Even if it has, it deforms as if it were loaded at one point. Therefore, it is possible to determine whether the glass sheet is supported at one point or a state where the glass sheet is supported on a line having a certain area by observing the state of the contour lines.

The inventor of the present invention varied the length of the contact portion (the length in the longitudinal direction of the front end of the support means) when supporting the atmospheric pressure applied to the sheet glass on a line having a certain area by the above-described method. Required a minimum length.

In this simulation, when the width of the tip of the supporting means is 0.05 mm, the calculation is performed by changing the length L of the tip in the longitudinal direction. 10 and 11 show stress distribution diagrams of the simulation. Length L in the longitudinal direction
Are 12 types from 0 (when supported at one point) to 20 mm.

As is clear from the stress distribution diagrams of FIGS. 10 and 11, the length of the support means at the tip end in the longitudinal direction is shown in FIG.
(A), (b) and (c) less than 2 mm (single point support,
In the case of (0.5 mm and 1 mm), the stress concentrates on almost one point (small area) 61, and the pitch of the iso-stress lines 62 is narrow and sharply concentrated. On the other hand, if the length in the longitudinal direction is 2
The stress is gently distributed over a relatively large area from the time when the distance exceeds mm (FIG. 10E). More specifically, 0mm,
In the stress distribution diagrams for 0.5 mm and 1 mm, as shown in the figure, one iso-stress line with the highest stress value appears as a small circle at the center of the portion corresponding to the tip, and the length of the tip at this level is It can be seen that this support works in the same way as a support with a pointed tip. On the other hand, from the stress distribution diagram in the case of 2 mm, two equal stress lines of the same size appear in parallel at the portion corresponding to the tip, and the tendency of one-point concentrated stress is observed. In the 3 mm stress distribution diagram, it can be seen that the concentration of the two isostress lines symmetrically distributed at the tip is completely divided.

Therefore, in order to effectively support the load due to the atmospheric pressure by using the support member having the wedge-shaped tip, the longitudinal length of the tip of the support means must be at least 2 mm or more. Further, as described above, the stress when the length in the longitudinal direction of the support is 2 mm or more becomes gentler with the length in the longitudinal direction, and the absolute value of the stress decreases as the contact area with the plate glass increases.

The present inventor has found that the minimum value of the length in the longitudinal direction of the tip of the support means for effectively supporting the atmospheric pressure is 2 mm by the present computer simulation, but taking into account practical and safety aspects. Then, it is desirable to set the length of the tip portion to be somewhat longer.

The computer simulation results shown in this embodiment are obtained when the width of the tip of the supporting means is set to 0.05 mm. Similar results were obtained at least up to a width of 0.5 mm of the tip. .

On the other hand, the length L in the longitudinal direction of the tip of the support means
As the length is increased, processing and assembling of the members become more difficult. For the processing of the members, the parallelism of the tip is extremely important because the tip must abut against the surface of the glass sheet in parallel, and extremely long ones in the longitudinal direction are difficult and practical (mass production). 30mm is the limit for the target. Furthermore, a member having a long length in the longitudinal direction of the distal end portion is not preferable in consideration of the forming accuracy of the sheet glass. In addition, since the tip must be arranged on the black stripe for assembling, positional accuracy and parallelism between the black stripe and the longitudinal direction of the tip during assembly are extremely important. Also,
The accuracy of assembling ordinary members in parallel is practically limited to 0.02 °, and assembling becomes extremely difficult when the tip of the supporting member exceeds about 30 mm.

In this embodiment, the front end of the plate member of the support member is formed in a wedge shape from a relatively thick metal round bar. The area connected to the rear panel is large, and it is relatively easy to assemble with high precision. be able to.

As shown in FIG. 9, the support means of this embodiment has a circular section 31b on the rear plate side and a wedge shape on the face plate side end 31a. As shown, the rear plate side has a plate-like supporting means 70.
Alternatively, it is needless to say that the case is also effective in the case of the rectangular support 71, or in the case where it is connected to a part of another member or another member, and the face plate side end is wedge-shaped and the end portion in the longitudinal direction. If the length is 2 to 30 mm, the effects and effects of the present invention are all exhibited. The present invention is also applicable to a case where some or all of the plurality of support members are integrated. Further, in this embodiment, metal is used as the material of the support member, but the present invention can be applied even if glass material, ceramics, or the like is used.

Although the present embodiment describes a cathode ray tube having a neck having a plurality of electron guns therein, the present invention is not limited to the above-described structure, and a support means is provided between two opposed flat plates. It is needless to say that the present invention can be applied to any supporting structure, for example, to a display device combining a linear cathode and electrostatic deflection. (Example 3)

FIGS. 1 to 5 show still another embodiment.
Next, a description will be given of a structure similar to that of the first embodiment shown in FIG.
In the present embodiment, as shown in FIG. 4, a flat glass material having a substantially rectangular opening 27 at a predetermined position is used as a rear plate. There are a method of blowing with high-pressure air or high-pressure water, a method of fusing with a laser, a method of using ultrasonic waves, and a method of using a grindstone, and can be processed relatively easily at room temperature. In addition, a secondary molding method in which the glass is heated to a temperature higher than the softening point of the glass can be used, or it can be processed by press molding.

Further, all of the face plate 21, the rear plate 23, and the side wall 22 are formed from a glass plate having the same thickness and the same material, and the funnel 24 is formed by a blow method. Further, the neck 25, the funnel 24, and the rectangular portion of the side wall 22 are heat-welded to each other, and frit glass is used for the other portions.

As described above, one face plate, 4
By using glass plates for one side wall, one rear plate, many funnels and neck, there is no need to use a face plate or rear plate with a curvature unlike a conventional cathode ray tube, and a display with a shorter overall length Equipment can be provided.

Further, since the atmospheric pressure is supported by the support means 31, sufficient strength can be obtained even with a relatively thin glass material having a thickness of preferably 4 mm to 15 mm in view of weight and strength. The weight becomes extremely lighter than that of. Also, by providing the support means 31, the deformation of the plate due to the atmospheric pressure can be made extremely small, and the amount of deformation is zero at the portion where the support means is provided and at the maximum at the center of each divided scanning area. The deformation amount is distributed substantially symmetrically with respect to the center, and the center axis of the electron gun does not tilt at all even after deformation, and the center of the electron gun does not tilt even after deformation. The axis can always be kept perpendicular to the screen plane. Therefore, a structure which is not affected by the deformation of the envelope due to the atmospheric pressure, which cannot be realized by the conventional cathode ray tube having no supporting means, becomes possible, and an extremely high-quality and stable image can be reproduced. In the display device of the present invention, the support means must be arranged on the boundary line of each divided scan in which the support means does not generate a shadow or reflection even when the electron beam is deflected and scanned.

In this embodiment, by using the support means as described above, the deformation of the envelope due to the atmospheric pressure can be made extremely small, and at the same time, the distribution of the deformation in each divided scanning area is substantially reduced with respect to the center of the area. It can be made symmetrical, and consequently, in any region, the central axis of the electron gun can be arranged perpendicular to the phosphor screen. This is a very great advantage for a cathode ray tube having an electron beam generator on the rear plate.

Further, since the distance between the electron gun and the phosphor screen can be relatively easily reduced, the magnification of the electron lens can be reduced, and a high-resolution image can be easily displayed. Also,
Since the structure of the present invention uses glass for the rear plate, the space through which the electron beam passes can be easily made a high-potential equipotential space as compared with the case where a metal plate is used. It is not necessary to electrically insulate the entire plate. Further, it is possible to avoid mutual interference of the magnetic fields of the adjacent deflecting devices via the metal plate, and to eliminate the influence of the magnetization of the metal plate.

In this embodiment, a plurality of rectangular openings 27 are provided at predetermined positions of the rear plate 23. The opening 27 does not necessarily have to be rectangular, but in order to reduce the power consumption of the deflection yoke attached to the outer wall of the funnel 24 connected to this opening, the opening shape should be the outermost trajectory of the electron beam. (Raster shape) is desirable. In the present invention, a flat rear plate is provided with an opening, and a funnel and a neck are connected to the opening, so that the power consumption of the deflecting device is greatly reduced by making the glass of the funnel part thinner, which is impossible with a conventional cathode ray tube. Although the power consumption can be greatly reduced, power consumption can be further reduced by using the above-described rectangular opening. In addition, in this embodiment, in addition to these power consumption reduction methods, by making the opening portion inclined, the distance between the electron beam passing through the outermost portion of the opening portion and the glass wall surface is reduced, and further, Small size and low power consumption of the deflection device can be realized. Also, mutual interference of magnetic fields generated between adjacent deflection devices can be reduced, and the advantage is extremely large. Further, there is an advantage that a wide space for disposing the internal structure such as the support means can be secured.

In this embodiment, the rear plate, the fennel, and the neck are separately molded, and the structure in which these are sealed is described. However, the present invention is not limited to this.
The rear plate, fennel and neck can be integrally molded. (Example 4)

This embodiment has the same overall structure as the above-described embodiment. Also in this embodiment, as shown in FIGS. 1 to 5, a rod-shaped support 31 is disposed between the face plate 21 and the rear plate 23 as support means. Each rod-shaped support has a tip 31a formed in a wedge shape, and a base 31b is fixed to the vicinity of a funnel joint portion of the rear plate 23. Since these supports support the face plate and the rear plate from the atmospheric pressure, it is necessary to have a certain contact area since it is necessary to minimize the glass distortion at the contact portion with the glass. The wedge shape is one of the means, and is arranged in any direction of the screen. In the case of a color cathode ray tube screen having a screen in which a striped light absorbing substance is arranged between striped phosphors, it is preferable to arrange wedge-shaped tips in the vertical direction along the striped light absorbing substance.

The size of the phosphor screen 30 formed on the inner surface of the face plate 21 is about 400 mm × 300 mm.
The atmospheric pressure applied to the screen is supported by twelve support means 31. The tips of the rod-shaped supports 31 contact the intersections 32 on the boundary of the divided areas R1 of the screen shown in FIG. 5, and the total number of the rods is 12.

As described above, in the vacuum envelope, a strong atmospheric pressure acts on the entire envelope. Increasing the number of supports to support the atmospheric pressure is more stable, but is not preferable in terms of mass production, and makes it difficult to process occluded gas and deteriorates the life characteristics.

As described above, the strength when the atmospheric pressure is applied to the face plate depends on the first factor determined by the thickness of the face plate glass and the arrangement interval of the support means, and the shape and size of the tip of the support means. The second decided by
There are factors. In the former, the face plate is deformed by a relatively large area due to the atmospheric pressure. Due to this deformation, a stress in the compression direction is generated on the outer surface of the face plate, and a stress in the tension direction is generated on the inner surface. Destroys when the critical value is exceeded. On the other hand, the latter
This is a fracture caused by stress in the tensile direction generated intensively in the glass near the tip of the support means when the face plate glass and the support means come into contact with each other. Generally, the support means comes into contact without large deformation of the whole glass In many cases, only one side of the side (inner side) is partially deformed. Therefore, by appropriately setting both the thickness of the face plate glass and the arrangement interval of the support means, and the shape of the tip end of the support means when the face plate glass and the support means come into contact with each other, it is possible to prevent both of the above-mentioned destruction factors. Thus, a display device having sufficient strength can be provided.

In this embodiment, since the thickness of the 20-inch face plate having the aspect ratio of 3: 4 is set to 5 mm, the weight of the face plate is only about 1.8 kg, and that of the face plate of the conventional pipe of the same size. The weight is considerably reduced as compared with the weight of about 9 kg, and the weight of the entire cathode ray tube is also significantly reduced.

Further, the screen is divided into five parts in the horizontal direction and four parts in the vertical direction. Therefore, there are 12 intersections 32 of the divided areas R1 of the screen shown in FIG. 5, and the rod-shaped supports are arranged at these intersections, so that the number is 12. The distance P between the supports is about 80 mm in the horizontal direction and about 75 mm in the vertical direction
Therefore, the average pitch is 78 mm. Therefore, t
/ P is 0.064.

The face plate 21 and the rear plate
The interval of 23 is 20 mm on the entire surface of the screen 30, and the length of the supporting means is also 20mm. The support means 31 is machined and has a diameter of 15
The wedge-shaped tip 31a has a width W of 0.05 mm and a length L in the longitudinal direction of the tip is 15 mm, which is the same as the diameter of the metal round bar. Further, the wedge-shaped tip portion 31a is in contact with the black stripe, which is the light absorbing layer of the screen 30, and the width of the black stripe is 0.07 mm. Since the number of the supports is only 12, the production is simple, and the release of the occluded gas under vacuum can be neglected, so that the life of the cathode ray tube is not deteriorated.

According to the simulation results performed by the inventors, when a display device having a flat glass face plate is formed, the thickness t of the face plate is set to 2 mm or more, and the interval P between the rod-shaped supports is set to 0.05 / P. By setting as described above, the face plate is deformed by a relatively large area due to the above-mentioned atmospheric pressure, so that a stress in the compression direction is generated on the outer surface of the face plate and a stress in the tensile direction is generated on the inner surface. Sufficient strength can be given to the first destruction factor that breaks when the stress (especially the stress in the tensile direction) exceeds a critical value. Further, the tip has a wedge shape, and the longitudinal length of the tip is longer. By using a supporting means having a wedge shape of 2 mm or more, when the face plate glass comes into contact with the supporting means, the pulling method which is concentrated on the glass near the tip of the supporting means Sufficient strength can be given to the second destruction factor caused by the directional stress. By combining these, it is possible to secure a flat vacuum envelope that effectively resists the first and second destructive factors and effectively supports the atmospheric pressure. The number of supports is very small, which has a large effect on the production and life of the tube. Moreover, the weight of the cathode ray tube can be reduced, so that a flat cathode ray tube with high practicality can be easily produced. Become.

The details of the simulation are the same as those shown in the first and second embodiments. It is desirable to reduce the number of supports in view of the operation of the tube.However, the peripheral edge of the face plate is supported by the side walls, so the drag against the atmospheric pressure is large. Gather at the center of the face plate that is easy to deform with
Thereby, the number of supports can be reduced.

If the thickness of the face plate is increased, the number of supporting means can be reduced. However, considering the weight of the face plate or the cathode ray tube, the thickness is desirably as thin as possible. Thickness 15
Those exceeding mm are not practical, and the production by the float method becomes difficult, resulting in poor productivity. Furthermore, the effect of the present invention is remarkable when the thickness of the face plate is thinner than that of a conventional cathode ray tube having no support means, and the thickness is desirably 10 mm or less. Lightweight and practical.

In a cathode ray tube in which a screen is divided and scanned by a plurality of electron guns as in this embodiment, it is necessary to arrange adjacent electron guns at a certain distance. The distance) depends on the structure of the electron gun, but it is impossible to make it less than 15 mm. When the support means is arranged at the intersection on the boundary of the divided area of the screen, the arrangement interval must be at least 15 mm. is there.

Therefore, considering the above range of the plate thickness, it is difficult to realize the ratio t / P exceeding the upper limit of 1.0, and the effect of this embodiment is remarkably 0.67 or less.
Desirably, it is 0.33 or less.

The supporting length in the longitudinal direction is 2 mm.
The stress in the above case becomes gentle with the length in the longitudinal direction as described above, and the absolute value of the stress decreases as the contact area with the plate glass increases, but the length L in the longitudinal direction of the tip of the support member is reduced. As the length increases, processing and assembly of the member become more difficult.

As for the processing of the member, it is necessary that the front end portion abuts in parallel with the surface of the sheet glass. Therefore, the parallelism of the front end portion is extremely important, and the extremely long one in the longitudinal direction is difficult and practical. 30mm is the limit for (mass production). Further, in consideration of the forming accuracy of the sheet glass, a member having a long length in the longitudinal direction of the tip portion is not preferable. Further, regarding the assembling, since the tip must be arranged on the black stripe, positional accuracy and parallelism between the black stripe and the longitudinal direction of the tip at the time of assembly are extremely important. In addition, the accuracy of assembling ordinary members in parallel is practically 0.02
Is the limit, and assembling becomes extremely difficult if the tip of the support member exceeds about 30 mm. Therefore, in the present embodiment, the thickness is set to 15 mm in consideration of the area of the non-light-emitting portion, the ease of processing the members, and the like.

Further, in this embodiment, the end of the plate member of the support member is not formed into a wedge shape but is formed from a relatively thick metal round bar, and the area to be connected to the rear panel is large. Can be assembled with high precision.

Further, in this embodiment, an electron gun as an electron source has been described in a structure in which the electron gun is sealed inside a neck provided on the second plate so as to face the small area to be divided and scanned. However, the relationship between the spacing of the support means and the thickness of the face plate and the shape of the tip of the support means are not limited to those having the above structure. That is, the supporting means is arranged between the face panel on which the phosphor screen is attached and the rear panel facing the phosphor panel to support the phosphor screen at a predetermined interval, and the phosphor screen is divided into a plurality of small areas by a plurality of opposed electron sources. This is extremely effective for a display device of a type that performs split scanning. Therefore, when the present invention is applied to a display device in which a linear cathode and an electrostatic deflection are combined, the lower limit of the interval between the support means by the electron gun structure as in the above embodiment can be further reduced, and as a result, the ratio t The possible range of the value of / P is widened. That is, the ratio t / P may be appropriately set according to the display device to which the present invention is applied.

[0080]

As described above, according to the present invention, a screen divided and scanned into a plurality of regions is integrally formed, a flat plate glass is used for a face plate having the screen, and a side wall connected to the face plate. A flat plate glass is also used for the rear plate connected to the funnel and the neck in parallel with the face plate, and a supporting means is provided between the flat plate glasses in a predetermined relationship, so that the vacuum surrounding the flat face rate with a small number of supporting means. Vessels can be formed. In addition, since the face plate and rear plate are flat and the distance between each electron gun and the screen can be set to a minimum, the electron lens magnification of the electron beam can be reduced, the spot on the screen is reduced, and a high-resolution image is obtained. To form The depth is reduced, the weight is reduced compared to the area of the screen, and the screen provides an image which is easy to see.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a cathode ray tube display device according to the present invention.

FIG. 2 is a schematic cross-sectional view of FIG. 1 cut along the line AA and viewed in the direction of the arrow.

FIG. 3 is a schematic cross-sectional view of FIG. 1 cut along a line BB and viewed in a direction of an arrow.

FIG. 4 is an exploded schematic perspective view showing a main part of the display device shown in FIG. 1;

FIG. 5 is a plan view showing a screen of the display device shown in FIG.

FIG. 6 is a cross-sectional view of a vacuum device for examining the proof stress of a glass face plate against atmospheric pressure.

FIG. 7 is a schematic sectional view showing a deformation of the glass face plate.

FIG. 8 is a characteristic diagram showing the relationship between the number of support means and the thickness of the glass face plate according to the simulation of the present invention.

FIG. 9 is a perspective view showing the shape of the support means of the present invention.

FIG. 10 is a stress distribution diagram obtained by simulating a stress distribution of glass due to contact of the support means.

FIG. 11 is a stress distribution diagram obtained by simulating a stress distribution of glass caused by contact of the support means.

FIG. 12 is a perspective view showing another example of the support means of the present invention.

13A and 13B are diagrams showing a conventional cathode ray tube, wherein FIG. 13A is a perspective view and FIG. 13B is a cross-sectional view.

FIG. 14 is a partially cutaway sectional view showing another conventional display device.

15 is a partially enlarged cross-sectional view of the display device shown in FIG.

FIG. 16 is a schematic diagram illustrating a state in which the support means of FIG. 14 contacts a screen.

FIG. 17 is a schematic diagram illustrating a modification of the support means shown in FIG.

[Explanation of symbols]

 21 ... Face plate 22 ... Side wall 23 ... Rear plate 26 ... Electron gun 30 ... Screen 31 ... Support means 31a ... Support means tip t ... Face plate thickness P ... Support means spacing W ... Tip width L ... Tip Length of section

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01J 29/87 H01J 31/00

Claims (3)

(57) [Claims] A first plate having at least a substantially rectangular shape, a side wall extending from a periphery of the first plate in a direction substantially perpendicular to the first plate, and A vacuum envelope including a flat second plate opposed to and substantially parallel to the vacuum plate, a phosphor screen attached to an inner surface of the first plate, and a plurality of the phosphor screens. A plurality of electron sources for generating an electron beam for dividing and scanning the small area, and a plurality of support means provided between the first plate and the second plate and supporting the plates at a predetermined interval. At least, the display device is characterized in that the ratio t / P is 0.05 or more, where t is the thickness of the first plate and P is the distance between the support means. 2. A substantially rectangular flat first plate;
A side wall extending from a peripheral portion of the first plate in a direction substantially perpendicular to the first plate; and a flat second plate disposed substantially parallel to the first plate. A vacuum envelope including: a phosphor screen attached to the inner surface of the first plate; and a plurality of electron sources for generating an electron beam for dividing and scanning the phosphor screen into a plurality of small areas. At least a plurality of support means provided between the first plate and the second plate to support the plates at a predetermined interval, and the first plate-side end of the support means has a wedge shape. A display device characterized in that the length of the wedge-shaped end in the longitudinal direction is 2 mm to 30 mm. 3. A substantially rectangular flat first plate;
A side wall extending in a direction substantially perpendicular to the first plate from a peripheral portion of the first plate, and a plurality of apertures arranged substantially parallel to and opposed to the first plate are provided. A second flat plate, a plurality of support means provided between the first plate and the second plate for supporting the plates at predetermined intervals, and a plurality of apertures of the second plate A vacuum screen comprising a funnel connected to each of the above, a neck extending from the funnel, and a phosphor screen applied to an inner surface of the first plate, and enclosed in the respective neck. An electron gun as an electron source, wherein the phosphor screen is divided and scanned into a plurality of small areas by electron beams from the plurality of electron guns, and the plurality of support means are provided on a boundary line of the divided scan. position Display device comprising has.