JPH07335146A - Image display device - Google Patents

Abstract

PURPOSE:To prevent spatter of glass fragments in the event of implosion of the glass bulb of a flat panel cathode-ray tube, enhance the contrast with external light, and reduce the halation caused by total reflection in the panel of the glass bulb. CONSTITUTION:A resin sheet 6 whose transmittance is adjusted is adhered directly to a glass bulb 1 using a bonding agent 7 etc. The resin sheet plays the role of a protection film when the glass bulb 1 goes in implosion to prevent spatter, and the incident external light is absorbed by the tint component of the sheet 6. Thus the contrast with the external light is enhanced to a great extent, and the total reflection light in the panel of the glass bulb 1 is absorbed, and the halation is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television device for displaying an image using a glass bulb.

[0002]

2. Description of the Related Art In an image display device for displaying a television image on a cathode ray tube (hereinafter referred to as a CRT) in order to obtain a television image, a large screen has been recently developed and a demand for a thinner image display device. Is getting bigger.
This is because, especially because the depth of the image display device is increased, it is difficult to install the image display device at home, which is a serious problem.

As a solution to this problem, a large number of electron beams emitted from a linear cathode (hereinafter referred to as a linear cathode) are controlled by a plurality of electrodes to irradiate a phosphor coated on a container to be a screen to emit light. Therefore, a method of forming an image (hereinafter referred to as a CFP method) has been proposed.
With this method, it is possible to realize an image display device having a depth of about one fifth of the conventional one. The applicant has already filed Japanese Patent Application Laid-Open
The CFP method is proposed as a flat-plate cathode ray tube described in Japanese Patent Laid-Open No. 130453. FIG. 9 is a configuration diagram of the flat panel type image display device shown in FIG. 8.

FIG. 8 is an exploded perspective view showing the internal structure of the flat panel image display device. In FIG. 8, 13 is a back electrode,
Reference numeral 12 denotes a horizontally extended linear cathode (only four are illustrated here), 14 denotes an electron beam extraction electrode, 15 denotes an electron beam modulation electrode, 16 denotes a vertical focusing electrode,
Reference numeral 17 is a horizontal focusing electrode, 18 is a horizontal deflection electrode, 19 is a vertical deflection electrode, and 22 is a face plate, the inner surface of which is coated with a phosphor.

14a is an electron beam extraction hole in the electron beam extraction electrode, 24 is an electron beam emitted from the linear cathode 12, and the electron beam 24 is apparently one electron due to the hole 14a in the electron beam extraction electrode. The image display section 21, which is a small section of the faceplate, is scanned while being directed into a beam, controlled by each of the electrodes 15-19, focused, and deflected. The inner screen portion 20 of the face plate 22 has R, G, B
The phosphor is printed and applied, and a high voltage is applied by forming a metal back layer, and the electron beam 24 is accelerated to high energy to excite the projecting phosphor in the metal back layer to emit light. The electron beam 24 causes the image display section 21 of the screen portion to emit an image portion of an image, and similarly, the other electron beams cause the other image display sections to emit an emission image, respectively, so that a desired image is displayed on the front surface of the screen. It is projected.

Reference numeral 23 is a back container, which is united and sealed with the front glass container 9 and then evacuated to form a flat image display device.

As described above, in the case of the CFP system, the conventional CR
Explosion-proof performance, which was not a problem with the T method, becomes a major issue. In other words, since the conventional CRT system has a large depth, by fitting a metal band on the side surface of the panel part of the cathode ray tube, the glass fragments generated when the cathode ray tube explodes due to some pressure due to the pressure implode into the inside of the cathode ray tube. , Dangerous shards of glass don't fly towards the viewer. However, in the CFP method with a small depth, glass fragments that have once been implosed collide with the electrodes inside the panel and rebound, and fly out to the observer side. This has been a big problem in the CFP method.

Further, in the CFP method, the total reflection light in the CFP panel causes a remarkable deterioration of image quality in the form of optical halation. That is, the light ray emitted from the phosphor first enters the CFP panel and is emitted to the observer side, but the light ray having an angle with the CFP panel at the time of emission exceeds a certain critical angle is not emitted from the CFP panel, The light is totally reflected and enters the phosphor surface to cause the phosphor to emit light. This is optical halation, and light is emitted in a place where light should not be emitted, which causes deterioration of image quality (see FIG. 5).

In order to solve such a problem, CFP
Introducing a resin transparent plate to the face plate of the panel,
There has been proposed an image display device configured to prevent explosion of fragments when the CFP panel explodes and to realize explosion-proof performance.

FIG. 4 shows one of the conventional examples. In the image display device 5, 1 is a glass bulb (C
FP panel), 2 is a transparent resin plate and is held in the cabinet 3. As the material of the transparent plate 2 made of resin, transparent plastic materials such as polycarbonate and acrylic are often used from the viewpoint of strength and optical properties.

When the CFP panel 1 explodes due to some kind of impact, the glass fragments are returned to the inside of the image display device 5 by the cabinet 3 and the transparent plate 2 made of resin and do not jump out to the outside so that the explosion-proof performance is maintained. Can be satisfied.

However, the image display device 5 having such a structure can satisfy the explosion-proof performance, but the contrast with respect to external light is significantly deteriorated. Generally, in image display devices that display images directly on the glass bulb,
The contrast to external light is expressed as the ratio of the brightness of the light emitted from the phosphor surface that reaches the observer through the glass bulb with respect to the brightness of the reflected light of the external light when the external light enters the glass bulb from the viewer side. Be done. From this, it can be seen that in order to improve the contrast with respect to external light, it is necessary to improve the efficiency of the light passing through the glass bulb of the image or to suppress the reflected light.

In the image display device 5 having the structure shown in FIG.
Since the transparent plate 2 made of resin and the CFP panel 1 are separated from each other, the light beam projected from the CFP panel 1 reaches the interface between the air layer and the transparent plate 2 made of resin until it reaches the observer 4.
After passing through the air layer and the resin layer, about 4% of the interface reflection occurs at each interface. In other words, due to the reflection at the interface, the transmitted light is about 9 when there is no transparent plate 2 made of resin.
It will be reduced to 2%. Even when external light is incident, about 4% of the reflection occurs at the interface between the air layer and the transparent plate 2 made of resin, and about 12% at the interface between the CFP panel 1 and the air layer. The external light is reflected by about 8% more than when the transparent plate 2 is not provided, and so-called reflection is increased (see FIG. 6).

As described above, in the image display device 5 shown in FIG. 4, the brightness of the transmitted light is lowered and the reflection of the external light is also increased. Therefore, the external light contrast is greatly increased by introducing the transparent plate 2 made of resin. Fall to.

Further, no effective countermeasure is taken for optical halation due to total reflection of light rays in the CFP panel 1.

Regarding the suppression of this optical halation, in the CRT system, a system in which the panel portion of the cathode ray tube is dyed with a dye or the like to absorb the totally reflected light is adopted.
However, the CFP method has not been introduced because of problems such as high cost.

[0017]

As described above, the CFP
With this method, the depth of the image display device is small, but this makes it more likely that debris will fly out to the viewer side during implosion, and it is necessary to add some explosion-proof function.

Further, in the CFP method, the occurrence of optical halation due to the totally reflected light rays inside the CFP panel causes a significant deterioration in image quality.

Further, in the structure in which the observer side resin transparent plate is introduced from the CFP panel in order to add the explosion-proof function, the contrast against external light is lowered due to the reflection at the interface with the newly generated air layer. Remarkable.

Conventionally, all the problems have not been dealt with effectively and positively in response to such a phenomenon. The present invention has been made for the purpose of solving such a problem, and provides an image display device capable of effectively and reasonably realizing explosion-proof performance and improving contrast against external light with an extremely simple structure. is there.

[0021]

The present invention has a vacuum glass bulb, and a resin sheet is directly attached on the outer surface of the tube surface of the front container of the glass bulb on which a television image or the like is displayed. An image display device having a configuration is provided.

[0022]

In the present invention, a resin sheet such as polyurethane or PET is directly attached on the tube surface of a glass valve such as a CFP panel so that even if the glass valve explodes, the resin sheet is a protective film. Plays the role of
Since it does not break, the glass fragments generated at the time of explosion are held by the resin sheet and do not jump out to the observer side,
Explosion-proof performance can be realized.

Further, according to the present invention, a resin sheet made of polyurethane or PET is directly attached on the tube surface of a glass bulb such as a CFP panel, that is, the resin sheet and the glass valve tube surface are adhered to each other without any optical gap. By doing so, there is no occurrence of an extra interface between the air layer and the resin layer or the air layer and the tube surface of the glass bulb due to the introduction of the resin sheet, and as a result, the reflection at the interface does not increase and There is no deterioration of the external light contrast due to the introduction of the sheet.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing the overall configuration of an image display device using a resin sheet according to the first embodiment of the present invention.

The image display device 5 has a CF in the cabinet 3.
This is a structure having a P panel 1, and a resin sheet 6 is directly attached to an observer side tube surface on the CFP panel 1 by an acrylic adhesive 7.
The spectral transmittance of the resin sheet 6 is as shown in FIG. 3, and the total light transmittance is about 70%. CFP panel 1 has the smallest spectral transmittance near the wavelength of 550 (nm).
This is because the color of the glass used for is green, and the effect is cancelled.

In the image display device 5 having such a structure, even if the CFP panel 1 explodes for some reason, the resin sheet 6 is adhered to the tube surface of the CFP panel without breaking, and thus the glass produced by the explosion The fragments will not scatter and will not jump to the observer 4 side.

In order to realize such an effect, the adhesive strength of the adhesive 7 with the glass bulb and the thickness of the base material of the resin sheet 6 are problems, but the inventor has based on the Electrical Appliance and Material Control Law. Explosion proof test by ball impact method and thermal shock method was performed, and in the polyurethane sheet and PET sheet, the base material had a thickness of 75 to 300 (μm) and the adhesive 7 had an adhesive force of 200 (g / cm). When a resin sheet, such as one with a glass bulb, is introduced on the glass bulb tube surface, the resin sheet acts as a protective film when the glass bulb explodes, breaking glass fragments. It was experimentally confirmed that the glass fragments did not fly out to the observer 4 side at all without holding them, and there was no risk of the fragments causing danger. (The test method is the explanation of the technical standard of electrical equipment,
It was carried out according to Appendix Table 8, (10), (b) and (c). Further, the inventor experimentally confirmed that the image display device 5 shown in FIG. 1 is significantly improved in contrast to external light as compared with the image display device shown in FIG. The experiment was conducted under the condition that the outside light was 160 (lx), and as a result, the resin sheet 6 of the present invention was compared with the conventional example.
It was confirmed that the contrast of the image display device 5 in which the above was introduced against external light is improved by about 35%.

Further, in the image display device 5 shown in FIG. 1, it was confirmed by experiments that the effect of reducing the optical halation is remarkable.

As a result, it was confirmed that the optical halation of the image display device 5 incorporating the resin sheet 6 of the present invention was reduced by about 36% as compared with the conventional example.

FIG. 2 shows a second embodiment according to the present invention.
The image display device 5 has a CFP panel 1 in a cabinet 3, and a resin sheet 6 according to the present invention is directly adhered to the CFP panel 1 by heat fusion.

The detailed specifications of the resin sheet 6 are the same as those in the first embodiment. However, in the image display device having such a structure, the resin sheet 6 and the resin sheet 6 are the same as those shown in the first embodiment. Since the CFP panel 1 is in close optical contact with each other without any gap, no extra interface is generated due to the introduction of the resin sheet 6, and therefore the external light contrast is not deteriorated at all. Then, the resin sheet 6 is dyed in the same manner as in the first embodiment,
By reducing the transmittance, the reflection of external light can be reduced, and the contrast to external light can be improved, and at the same time C
Totally reflected light in the FP panel 1 can be absorbed and optical halation can be reduced.

Further, the resin sheet is dyed with blue smoke or gray smoke with a dye or a pigment to reduce the total light transmittance, so that the external light incident on the glass bulb is transmitted through the resin sheet. It is attenuated by absorption, then transmitted through the resin sheet again after being reflected by the phosphor surface, attenuated by absorption and emitted to the observer side. Therefore, the reflection of the incident external light is extremely reduced, and the contrast with respect to the external light can be remarkably enhanced as compared with the case where the resin sheet is not introduced (see FIG. 7).

Further, according to the present invention, a resin sheet whose total light transmittance is reduced by dyeing is directly attached on the tube surface of a glass bulb such as a CFP panel to obtain the same effect as dyeing the panel portion of the glass bulb. Is obtained. That is, the light beam emitted from the phosphor is incident on the panel and passes through the resin sheet when it is emitted, but the light beam whose angle at the time of emission from the resin sheet exceeds the critical angle is made of resin. Total reflection occurs at the interface between the sheet and the air layer. However, at this time, since the totally reflected light is absorbed by the dye in the resin sheet, the intensity of the light incident on the phosphor is extremely reduced, and as a result, the optical halation is suppressed very effectively. You can

[0034]

As described above, according to the present invention, glass fragments are prevented from scattering when the glass bulb explodes, and the contrast against external light is improved by reducing the reflectance of external light. In order to reduce the optical halation by absorbing the total internal reflection light at the same time, the resin sheet with the adjusted transmittance was pasted directly on the glass bulb tube surface. It is possible to provide a simple, low-cost, and highly reliable image display device, which has an extremely large impact on the industry.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a first embodiment of an image display device of the present invention.

FIG. 2 is a partial cross-sectional view of a second embodiment of the image display device of the present invention.

FIG. 3 is a diagram showing a spectral transmittance curve of a resin sheet according to the first embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of a conventional image display device.

FIG. 5 is a schematic diagram showing optical halation, CF
Sectional drawing which showed a part of panel part of P panel 1.

FIG. 6 is an optical path diagram of external light in a conventional image display device.

FIG. 7 is an optical path diagram of external light in the image display device according to the present invention.

FIG. 8 is an exploded perspective view showing an internal configuration of the image display device.

[Explanation of symbols]

 1 CFP panel 2 Transparent plate made of resin 3 Cabinet 4 Observer 5 Image display device 6 Sheet made of resin 7 Adhesive 8 Phosphor 10 Total reflected light 11 External light 12 Linear cathode 13 Back electrode 14 Beam extraction electrode 15 Beam modulation Electrode 16 Vertical focusing electrode 17 Horizontal focusing electrode 18 Horizontal deflection electrode 19 Vertical deflection electrode 20 Screen 21 Image display section 22 Face plate 23 Rear container 24 Electron beam

Claims (1)

[Claims] 1. A front container having a screen formed by coating a phosphor on an inner surface thereof, and a back container facing the front container, wherein a plurality of lines are provided in a space sandwiched between the back container and the front container. A cathode, an electron beam extraction electrode for extracting an electron beam from the line cathode, and a back electrode provided opposite to the electron beam extraction electrode with the line cathode interposed therebetween,
An electron beam modulating electrode for controlling the passing amount of the electron beam and a deflecting electrode for deflecting the electron beam horizontally and vertically are provided, and the controlled electron beam emits light by colliding with the phosphor. An image display device for displaying an image according to claim 1, wherein a resin sheet is attached to the outer surface of the front container.