JPH03236137A - Vacuum container for display device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of excessive stress on a connection section to a front plate by forming a back plate constituting a vacuum container into a two-layer structure of a low-rigidity back plate and a high-rigidity back plate so that the high-rigidity back plate is covered by the low-rigidity back plate. CONSTITUTION:A high-rigidity back plate 2a presses a front plate 1 with the action of the atmospheric pressure via the seat 4 of a metal plate. A low-rigidity back plate 2b is stuck to the front plate 1 at the outer edge section via low- melting point glass 3 so as to incorporate the back plate 2a. Since the back plate 26 is supported by the back plate 2a, its deformation is suppressed small by the atmospheric pressure, and no crack is generated at a connection section. The back plate 26 has low rigidity against a temperature change, thus the thermal expansion difference between the back plate 2b and the front plate 1 can be absorbed by the back plate 2b, and no crack is generated at the connection section.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vacuum container for a display device, particularly a flat panel display device.

Despite the active development of electron tube type flat display devices compared to conventional technology, in principle these flat display devices require a force similar to that of conventional CRT type display devices (distance from cathode to anode). This is a device that is significantly smaller than the conventional CRT system and realizes a thin flat display device.For this reason, this flat display device has matrix electrodes that can be inserted into a box-shaped vacuum container, making it possible to reduce the distance mentioned above. Although it is common to have a structure, the electrons emitted from the cathode are collected and deflected by this electrode structure. FIG. 4 shows a vacuum container of a conventional flat panel display device in cross section at a position including the joints of the constituent members of the container.

The container is formed by airtightly joining a front plate 1 and a box-shaped metal molded back plate which abuts at the outer edge of the back side with a low melting point glass 3. Within this container (above) the above-described electrode assembly (not shown) is placed.

The electrical connection between this electrode structure and the outside of the container (e.g.
On the front plate I This is accomplished by a metal vapor deposited film that passes through the joint formed by the low melting point glass 3 and communicates the inside and outside of the container. Containers have the following contradictory issues when increasing the size of the display device. First of all, transformation occurs on the back plate due to the force of atmospheric pressure that inevitably increases as the device becomes larger. Especially at the joints. Because the deformation that occurs must be kept to a minimum! 2. It is necessary to increase the rigidity of the back plate. If the strength of the back plate,
If deformation occurs at the joint due to insufficient rigidity, the low melting point glass 3 or the glass front plate 1 at the joint may be damaged.
Excessive stress is generated in the joints, resulting in cracks, etc., which can lead to fatal situations such as a decrease in the degree of vacuum inside the container.
It has the opposite effect on temperature changes.

Glass front plate blown out as display devices become larger
The difference between the amount of dimensional change due to temperature change and the back plate increases.

In this case, if the rigidity of the back plate is as high as mentioned above, the back plate cannot absorb this difference in dimensional change through its own deformation, which causes breakage, especially at the joint between the back plate and the front plate. Temperature changes like this are unavoidable in electron tube type display devices that require heat treatment for the purpose of solidifying low-melting glass or baking the electrode structure inside the vacuum container. This contradictory problem is a serious problem especially when the equipment becomes larger.

An object of the present invention is to solve the above problems and provide a vacuum container for a display device.Means for Solving the Problems Means for solving the above problems are as follows.

The vacuum container has at least two back plates: a low-rigidity back plate for airtightness and a high-rigidity back plate that can withstand atmospheric pressure.
The outer edge of the high-rigidity back plate is pressed against the outer edge of the front plate, and the low-rigidity back plate C covers the high-rigidity back plate and is joined to the outer edge of the front plate at the outer edge. As mentioned above, the back plate has a two-layer structure, so that the airtightness of the container is maintained by the low-rigidity back plate, and the strength against atmospheric pressure is improved by the high-rigidity back plate. Vacuum sealing of the container (above) is achieved by joining the front plate and the low-rigidity back plate. Differences in thermal expansion due to temperature changes are absorbed by the low-rigidity back plate. L% and high rigidity back plate (
Above: It is only pressed against the front plate by the action of atmospheric pressure, and the difference in thermal expansion between the two is absorbed by the sliding between the two, so no stress is generated at the joint (~ Ma? = increasing amount) The low-rigidity back plate is supported by the high-rigidity back plate, and deformation that occurs at the joint between the low-rigidity back plate and the front plate is minimized, preventing cracks at the joint. Fig. 1 is a cross-sectional view of the essential parts of a vacuum container according to the first embodiment of the present invention. Low-rigidity back plate 2b is a low-rigidity back plate 2b, even if it is pressed against the front plate 1 by the action of atmospheric pressure through the metal plate seat 4. Even though the back plate 2b is bonded to the front plate 1 by 1, in this embodiment, since the back plate 2b is supported by the highly rigid back plate 2a, the deformation caused by the increasing atmospheric pressure is suppressed to a small extent, and cracks do not occur at the joint. There is no difference in thermal expansion between the back plate 2b and the front plate l.
This prevents cracks from occurring at the joints (-Also, the highly rigid back plate 2bi &
Since it is not fixed to the front plate 1, the difference in thermal expansion is absorbed by the sliding between the two.

This embodiment Ii is particularly useful in increasing the size of the device.

(Second Embodiment) FIG. 2 shows a main part sectional view of a container according to a second embodiment of the present invention.

A vacuum container for the display device is obtained by providing a plurality of holes in the back plate 2b and airtightly joining them with low melting point solder glass.

Back plate 2bU-layer is firmly joined to front plate l (Third embodiment) A third embodiment of the present invention is shown in FIGS. 3(a) and 3(b). The outer edge of the back plate 2b is sandwiched and joined by metal plates 5a or glass rods 5b to form a vacuum container.

Compared to the second embodiment, the -layer bonding strength is improved and the airtightness of the joint is further improved.
It is also possible to make the receiver seat 4 integral with the back plate 2b by spot welding or the like. In order to prevent this, a force is placed on the second window for the purpose of preventing the above-mentioned edge from coming into contact with the glass front plate l, causing cracks in the front plate (low melting point glass is on the back side). In the case where the coating is applied only to the outer edge of the face plate 2b, this seat is not essential.The effect of the present invention Ct As described above, the present invention satisfies the contradictory demands associated with the increase in the size of the device and solves the conventional problems. It is a dog and has a dog effect.

[Brief explanation of drawings]

1 to 3 are cross-sectional views of essential parts of a vacuum container in an embodiment of the present invention. FIG. 4 is a cross-sectional view of a vacuum container of a conventional display device. 1...Front plate, 2.2a...Low rigidity back plate 2b
...High rigidity back plate, 3...Low melting point solder glass 4
...Receiver gL 5a, 5b...Reinforcement plate

Claims (3)

[Claims] (1) A vacuum container for a display device consisting of a front plate made of a transparent glass plate and a box-shaped back plate made of metal bonded to the periphery of the back surface of the front plate, wherein the back plate is a low-rigid back plate. It has at least a two-layer structure of a face plate and a high-rigidity back plate, and the high-rigidity back plate is included in the low-rigidity back plate, and the low-rigidity back plate and the front plate are fixed to each other. Vacuum container for display device. (2) The vacuum container for a display device according to claim 1, characterized in that a plurality of equally spaced holes are provided in the joint portion of the low-rigidity back plate. (3) The display device according to claim 1, wherein the low-rigidity back plate and the front plate are joined by sandwiching the joining edge of the back plate with a metal plate or a glass rod. container.