JPH11143371A - Filter for display device and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device filter and a display device capable of preventing the drop of contrast on a display screen which may be generated at the time of reinforcing the mechanical strength of a CRT, to thin panel glass or forming a reflection preventing film. SOLUTION: A display device filter stuck to a display panel surface of a display device to reinforce the mechanical strength of the display device is constituted of a filter base material 18 and an adhesive layer 12 formed on an adhesive face between the base material 18 and the display panel surface and having a function for controlling the transmissivity of visible light to a prescribed value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter for a display device such as a cathode ray tube and a display device having the display device filter on a display panel surface of the cathode ray tube.

[0002]

2. Description of the Related Art A cathode ray tube (hereinafter referred to as CRT (Cathode Ray
Japanese Patent Application Laid-Open Nos. 52-87352 and 52-87353 discloses a technique of bonding a plastic explosion-proof film to the panel glass surface of a CRT as a means for preventing glass from scattering due to implosion. It has been disclosed. By bonding the explosion-proof film to the display panel surface of the CRT, a part of the glass scatter prevention function that has relied only on the panel glass and the tension band can be transferred to the explosion-proof film. This makes it possible to reduce the thickness of the panel glass.
This is very effective in practical use for reducing the weight of a display device using.

On the other hand, in a CRT, static electricity is generated on a display surface by turning on and off a high drive voltage, and attracts surrounding dust, and when touched by hand, causes an electric shock to cause discomfort. To prevent the above problem, for example, as disclosed in Japanese Patent Application Laid-Open No. 8-287850, a display panel surface of a CRT is coated with an antistatic material to form an antistatic film. It is effective to discharge static electricity by setting the resistance to 10 ⁹ Ω / □ or less and connecting to a case having a ground potential.

The above antistatic film is obtained by mixing a fine powder of an electrically conductive substance such as tin oxide or ITO as a filler with a resin such as rubber, acrylic, silicon or epoxy resin. The mixture can be formed by coating the obtained mixture on a film and curing the mixture by heating, ultraviolet irradiation, or electron beam irradiation.

When an object is viewed through a transparent material, it is very troublesome that the reflected light is strong and the reflected image is clear. For example, in a spectacle lens, when a reflected image called a ghost, a flare, or the like is generated, it causes discomfort to eyes. Further, in the case of a looking glass or the like, there is a problem that the contents are not clear due to the light reflected on the glass surface. The same problems as described above also occur in CRTs, and there is an increasing demand to provide an anti-reflection function to the display panel surface of CRTs in order to avoid these problems.

Conventionally, in order to prevent the reflection of light which causes the above problem, there is provided an antireflection film formed by coating a substance having a refractive index different from that of the substrate on the substrate by a vacuum deposition method or the like. A method of bonding an antireflection filter to a display panel surface of a CRT has been used. In this case, it is known that in order to maximize the antireflection effect, it is important to select the thickness of the antireflection film covering the base material. For example, when the anti-reflection film is formed as a single layer, a material having a lower refractive index than the base material is used as a material for forming the anti-reflection film, and 光 of the wavelength of the light to be anti-reflection or an odd number thereof It is known that forming the anti-reflection film by selecting the optical film thickness twice gives a minimum reflectance, in other words, a maximum transmittance. Here, the optical film thickness is given by the product of the refractive index of the material forming the antireflection film and the film thickness of the antireflection film. Further, it is possible to form an anti-reflection film having a multilayer structure. In this case, the selection of the film thickness is described, for example, in the literature (Optical Technology Contact, Vol. 9, No. 8, pp. 17 (197)
Several proposals have been made in 1)).

As the material for forming the antireflection film, an inorganic oxide or an inorganic halide is mainly used in many cases, and generally has both low reflectance and high transmittance in the visible region.

[0008]

However, in a conventional CRT, the transmittance of the display light emitted from the fluorescent screen inside the CRT is adjusted by a panel glass. If the panel glass thickness is reduced by making it possible to reduce the weight, the transmittance of the display light becomes too high, and the contrast of the displayed image is reduced.

Also, by forming an antireflection film made of an inorganic oxide or the like on the display panel surface of a CRT, light is not substantially absorbed by the antireflection film and reflection on the surface is reduced. As a result, the effective transmittance of light is further increased, and the contrast of the displayed image is deteriorated in the same manner as described above. In this case, in order to adjust the transmittance to a desired value without changing the thickness of the panel glass, it can be easily coped with by generally changing the material of the panel glass. However, according to this method, an antireflection film is formed. It becomes necessary to use different glass materials for the ones that are not to be used, and the glass materials must be switched frequently, resulting in a decrease in productivity and an increase in manufacturing costs.

Further, in a CRT having a flat display panel surface, the mechanical strength is fundamentally weakened. Therefore, in order to secure the strength, the glass thickness of the end portion of the display panel surface or the like is adjusted to a general CRT. It has to be thicker than the glass thickness of the place where it does. This causes a problem that the brightness of a display image such as a character or a picture is clearly different between the center and the end of the display panel surface. From this point, it is desired to use a transparent glass (clear glass) as much as possible for the panel glass material, and this also tends to increase the transmittance of display light.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and accordingly, an object of the present invention is to provide a CRT having a mechanical strength which is reduced when a panel glass is thinned or an antireflection film is formed. Of a display device, such as a CRT, which can prevent a decrease in contrast of a display screen caused by the display device and can be preferably adhered to a CRT having a flat display panel surface, and a display device having the display device filter on the display panel surface of the CRT. It is to provide.

[0012]

In order to achieve the above object, a filter for a display device according to the present invention is used for a display device which is adhered to a display panel surface of the display device to enhance the mechanical strength of the display device. A filter, comprising: a filter substrate; and an adhesive layer formed on an adhesive surface between the filter substrate and the display panel surface, the adhesive layer having a function of adjusting a visible light transmittance to a predetermined value.

The above-described filter for a display device of the present invention adheres to the display panel surface of the display device to enhance the mechanical strength of the display device. In the case of bonding to a display panel of a CRT, since the filter for a display device of the present invention enhances the mechanical strength of the CRT, the thickness of the panel glass can be reduced, and the weight can be reduced. Further, if the transmittance of display light emitted from the fluorescent screen inside the CRT becomes too high by reducing the thickness of the panel glass, the contrast of the displayed image is reduced. Since the adhesive layer formed on the bonding surface with the display panel surface of the display device has a function of adjusting the transmittance of visible light to a predetermined value, it is possible to appropriately adjust the transmittance of display light. This makes it possible to suppress a decrease in contrast of a display image.

The above-described filter for a display device of the present invention preferably has a function of adjusting the transmittance of the visible light to a predetermined value by containing at least the dye or the pigment in the adhesive layer. I have. By adjusting the content of the dye or pigment, the transmittance of visible light can be easily adjusted to a predetermined value.

In the display device filter according to the present invention, preferably, an anti-reflection film is formed on a surface of the filter substrate opposite to the surface on which the adhesive layer is formed, and more preferably. The antireflection film is formed of two or more layers. Thereby, reflected light from the display panel surface of the display device can be suppressed. Also, since the adhesive layer formed on the adhesive surface of the display device with the display panel surface can adjust the visible light transmittance to a predetermined value, the display light transmittance can be appropriately adjusted. Thus, it is possible to suppress a decrease in the contrast of a displayed image due to an increase in the effective transmittance of display light by forming an anti-reflection film.

In the above-mentioned filter for a display device of the present invention, preferably, an antistatic film is formed on a surface of the filter substrate opposite to the surface on which the adhesive layer is formed. Thereby, it is possible to further prevent generation of static electricity on the display surface of the display device.

Further, in order to achieve the above object, a display device of the present invention is provided on a display panel surface of a cathode ray tube having a fluorescent screen on its inner surface which is illuminated by an electron beam emitted from an electron gun. A display device to which a filter for enhancing the mechanical strength of the filter is adhered, wherein a function of adjusting a transmittance of visible light to a predetermined value is achieved by a bonding surface of the filter base material of the filter and a display panel surface of the cathode ray tube. Are bonded by an adhesive layer having

The display device of the present invention described above uses a cathode ray tube (C
Since a filter is adhered to the display panel surface of (RT), thereby enhancing the mechanical strength of the CRT, the thickness of the panel glass can be reduced, and the weight of the display device can be reduced. Also, if the transmittance of the display light emitted from the fluorescent screen inside the CRT becomes too high by reducing the thickness of the panel glass, the contrast of the displayed image is reduced, but an adhesive for bonding the filter and the display panel surface is used. Since the layer has a function of adjusting the transmittance of visible light to a predetermined value, the transmittance of display light can be appropriately adjusted, and a decrease in contrast of a display image can be suppressed.

In the above display device of the present invention, preferably, the display panel surface of the cathode ray tube is substantially flat. CR
When the display panel surface of T is substantially flat, it is preferable to use a transparent glass (clear glass) as the panel glass material as much as possible, which increases the transmittance of display light. Since the adhesive layer that adheres to the panel surface has a function of adjusting the transmittance of visible light to a predetermined value, it is possible to easily adjust the transmittance of display light appropriately.

The display device of the present invention preferably has a function of adjusting the transmittance of the visible light to a predetermined value by containing at least the dye or the pigment in the adhesive layer. By adjusting the content of the dye or pigment, the transmittance of visible light can be easily adjusted to a predetermined value.

In the above display device of the present invention, preferably, an anti-reflection film is formed on a surface of the filter substrate opposite to the bonding surface. It is formed of a film having at least two layers. Thereby, reflected light from the display panel surface of the display device can be suppressed. In addition, by adjusting the transmittance of visible light to a predetermined value by the adhesive layer, the transmittance of display light can be appropriately adjusted, and an antireflection film is formed to effectively transmit display light. It is possible to suppress a decrease in contrast of a displayed image due to a further increase in the rate.

In the above display device of the present invention, preferably, an antistatic film is formed on a surface of the filter substrate opposite to the bonding surface. Accordingly, it is possible to further prevent generation of static electricity on the display panel surface of the display device.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a filter for a display device and a display device according to the present invention will be described in detail based on an embodiment shown in the drawings.

First Embodiment FIG. 1 is a sectional view of a filter for a display device according to this embodiment. The display device filter 1 according to the present embodiment includes a transparent plastic filter substrate 18 and a hard coat film 1.
7, antistatic film 16, antireflective film 15, and antifouling film 1
4 and the functional film 1
Adhesive layer 1 formed on an adhesive surface with display panel surface 1
And 2.

The material of the transparent plastic filter substrate 18 may be any material as long as it is formed of a material composed of an organic polymer. However, optical properties such as transparency, refractive index and dispersion, impact resistance and heat resistance Or various properties such as durability, for example, polymethyl methacrylate and its copolymer, polycarbonate, diethylene glycol bisallyl carbonate, di (meth) acrylate polymer of (brominated) bisphenol A and its copolymer, (brominated ) Bisphenol A mono (meth) acrylate urethane-modified monomer polymer and copolymer, polyester such as polyethylene terephthalate, polyethylene naphthalate or unsaturated polyester, acrylonitrile-styrene copolymer, vinyl chloride, polyurethane An epoxy resin or an aramid resin, can be preferably used. The thickness of the filter substrate 18 is not particularly limited, but is, for example, 25 to
It is preferably about 500 μm.

It is preferable to form a hard coat layer 17 having a thickness of, for example, 3 to 10 μm on the surface of the filter substrate 18 which faces the adhesive layer 12, so that the adhesion,
Various properties such as hardness, chemical resistance, durability, abrasion resistance, and dyeability can be improved. Examples of the material of the hard coat layer 17 include Japanese Patent Publication No. Sho 50-28092, Japanese Patent Publication No. Sho 50-28446, and Japanese Patent Publication No. Sho 50-3.
No. 9449, JP-B-51-24368, JP-A-52-112698, JP-B-57-2735, etc., using a conventionally known material as a surface-hardening coating of a plastic substrate. be able to.
Further, an acrylic cross-linked product obtained from (meth) acrylic acid and pentaerythritol may be used. As a method of forming the hard coat layer 17, for example, after applying an acrylic crosslinkable resin material to the upper layer of the filter base material 18,
A method in which a cross-linking curing reaction is caused by irradiation with ultraviolet rays or electron beams to cure the resin, or a method in which a silicone, melamine, or epoxy resin material is applied and cured by a thermosetting reaction. Can be used.

On the upper layer of the hard coat layer 17, a transparent antistatic film 16 made of a conductive film such as an ITO thin film having a thickness of, for example, 15 nm to 150 nm formed by an evaporation method or a sputtering method is formed.

The anti-reflection film 15 for reducing reflection of external light and reproducing desirable image and character information may have a single-layer structure or a multilayer structure, but is a multilayer optical thin film in which thin-film materials having different refractive indexes are alternately laminated. Preferably, there is. As a method of forming the anti-reflection film, various physical film forming methods (PVD (Physical Vapor Deposition) methods) represented by a vacuum evaporation method, an ion plating method, and a sputtering method, and a spray method (“low electric field corresponding to a leakage electric field”) are used. Reflective Coating ", see the Technical Report of the Institute of Television Engineers of Japan, Vol. 10, No. 2, '95 .1), a chemical film forming method such as an immersion method, a CVD (Chemical Vapor Deposition) method, and a coating method. PVD above
In the method, in addition to SiO ₂ , Al ₂ O ₃ , ZrO ₂ , TiO ₂ , TaHf ₂ , SiO
, TiO ₂ , Ti ₂ O ₃ , Y ₂ O ₃ , Yb ₂ O ₃ , MgO, and CeO ₂ can be preferably used.

The antifouling film 14 formed on the outermost surface of the functional film 11 does not easily adhere to fingerprints and other stains when directly touching the surface, and the attached stains are easily wiped dry or wiped with water. Can be removed. As a material constituting the antifouling film 14, a thin film of a coating agent containing a perfluoro group on a silicone resin base, a coating agent containing a perfluoro group on an acrylic resin base, or the like is used.

The adhesive layer 12 formed on the bonding surface of the functional film 11 with the display panel surface is made of, for example, an epoxy-based material.
The main component is a rubber-based, acrylic-based, or silicone-based adhesive with an ultraviolet crosslinking reaction accelerator added, and the dye or pigment is added at a predetermined concentration to increase the visible light transmittance to a predetermined value. It has the function of adjusting For example, bisphenol A type epoxy (meth) acrylate having a molecular weight of 550 or more: 10% by weight, urethane (meth) acrylate: 20% by weight, hydroxyl group-containing mono (meth) acrylate: 65% by weight, and a photopolymerization initiator:
A composition containing 3% and an additive: several% can be used. From the viewpoints of transmittance stability, uniformity, durability and the like, it is preferable to use a dye. In selecting a dye or pigment, it is possible to intentionally use a material having a desired color, such as black or gray. Also,
The adhesive layer 12 has a haze value of 20 in order not to degrade the quality of characters and figures displayed on the display screen.
% Or less, preferably 5% or less. The transmittance of the adhesive layer 12 is preferably 90% or less, more preferably 40% to 90%. Further, as the adhesive layer 12, it is preferable to use an adhesive layer adjusted such that the difference between the refractive index of the cured product thereof and the refractive index of the material constituting the display panel of the display device is within 0.8%.

The above-mentioned adhesive layer 12 is formed on the surface of the functional film 11 to be bonded to the display panel surface after removing the bubbles contained in the adhesive having the above-mentioned predetermined transmittance. For example, it can be formed by coating by a flow coating method, a roll coating method, a bar coating method, or the like, followed by drying.

The antistatic film 16 formed on the functional film 11 is connected to a ground potential via a conductive tape or the like, so that charges accumulated on the display panel surface can be escaped to provide an antistatic effect. Can be.

The filter for a display device according to the present embodiment is provided on a display panel surface of a display device such as a CRT.
After applying pressure using a roller such as a rubber roller or metal roller while applying pressure so that air bubbles do not remain or wrinkle, adhere through a solidification process of the adhesive layer such as ultraviolet irradiation, electron beam irradiation, etc. Can be used.

The filter for a display device according to the present embodiment can be used by being adhered to a display panel surface of a display device such as a CRT. In a CRT, the panel glass can be made thinner by increasing the mechanical strength of the display device to reduce the weight of the display device, and the display screen generated when the panel glass is made thinner or an antireflection film is formed. A decrease in contrast can be prevented. Further, since it is not necessary to switch the material of the panel glass, the above-mentioned effect can be obtained without lowering the productivity. In addition, since an antireflection film and an antistatic film are provided on the filter substrate, light reflected from the display panel surface of the display device can be suppressed, and static electricity can be generated on the display surface of the display device. This can be prevented from occurring.

Second Embodiment FIG. 2 is a schematic sectional view of a display device (color cathode ray tube (CRT)) according to this embodiment. The panel 21, the funnel 22, and the neck tube 23 constitute a vacuum container, and the panel 21 and the funnel 22 are joined by frit glass. A tension band 29 for explosion proof is wound around the outer periphery of the panel 21. Tension band 2
A mounting ear 30 is formed on the outer periphery of 9, and the CRT is mounted inside the television as a display device via the mounting ear 30. The tension band 29 or the mounting ear 30 is made of a conductive material such as a metal, and is grounded through a ground wire 32.

On the inner surface of the panel 21, a phosphor screen 26 coated with blue, green, and red light emitting phosphors is formed, and a color selection mask 25 is arranged close to the phosphor screen 26. The color selection mask 25 is held by a mask holding frame,
A magnetic shield 27 is mounted on the electron gun side.

The electron beam 28 from the electron gun 24 housed in the neck 23 passes through the color selection mask 25 and reaches the phosphor screen 26 formed on the inner surface of the panel, and excites a predetermined phosphor to emit light.

The functional film 11 is substantially the same as that of the first embodiment. For example, a filter substrate 18 made of a transparent plastic, a hard coat film 17, an antistatic film 16, an antireflective film 15, The antifouling film 14 is provided. Each of the above layers can be formed of the same material as in the first embodiment.

The antistatic film 16 formed on the functional film 11 is connected to a ground potential via a conductive tape 31, a tension band 9, and a mounting ear 10 adhered to a plurality of positions on the outer periphery of the functional film 11. The surface charge is released via the ground wire 32 to provide an antistatic effect. The conductive tape 31 is not particularly limited,
For example, a metal foil tape is used, and the surface resistance between the conductive tapes 31 attached to the electrode portions formed at both ends of the functional film adhered to the surface of the panel 21 is, for example, 200.
0 Ω or less.

The above-mentioned functional film 11 is adhered to the panel 21 by an adhesive layer 12. Adhesive layer 12
The main component is, for example, an epoxy-based, rubber-based, acrylic-based, or silicone-based adhesive having an ultraviolet crosslinking reaction accelerator added thereto as a main component, and a dye or pigment is added at a predetermined concentration to generate visible light. It has a function of adjusting the transmittance to a predetermined value. For example, bisphenol A type epoxy (meth) acrylate having a molecular weight of 550 or more: 1
A composition containing 0% by weight, urethane (meth) acrylate: 20% by weight, hydroxyl-containing mono (meth) acrylate: 65% by weight, photopolymerization initiator: 3%, and additive: several% Can be used. From the viewpoints of transmittance stability, uniformity, durability and the like, it is preferable to use a dye. In addition, when selecting a dye or pigment,
A material having a desired color other than gray can be used intentionally. The adhesive layer 12 has a haze value of 20% or less, and preferably 5% or less, so as not to deteriorate the quality of characters and figures displayed on the display screen. The transmittance of the adhesive layer 12 is preferably 90% or less, more preferably 40% to 90%. In the adhesive layer 12, the difference between the refractive index of the cured product and the refractive index of the material forming the display panel of the display device is 0.1.
It is preferable to use one adjusted to be within 8%.

The adhesive layer 12 is used to remove bubbles contained in the adhesive film 12 before application, so that the functional film 1
A known method, for example, a flow coating method,
Apply by roll coating, bar coating, etc.
It can be used after drying. Further, it can be applied directly on the surface of the panel 21 by the above method.

When the panel 21 and the functional film 11 are bonded together with the adhesive layer 12 interposed therebetween, the functional film 11 is pressed against the surface of the panel 1 by using a pressure roll or the like to make the thickness of the adhesive layer 12 uniform. So that no air bubbles remain or streaks or wrinkles appear on the surface. The thickness of the adhesive layer 12 is, for example, about 0.05 to 2.5 mm. As the pressure roll, a metal roll, a hard rubber roll, a rubber lining metal roll, or the like can be used.

When the adhesive layer 12 is solidified from the functional film 11 by, for example, ultraviolet irradiation or electron beam irradiation, a metal halide lamp, a high-pressure mercury lamp, a xenon lamp, or the like is used as an ultraviolet irradiation light source. And the irradiation energy is 30
About 0 to 500 mJ / cm ² is appropriate.

According to the display device of the present embodiment, C
It is possible to reduce the weight of the display device by bonding it to the RT panel surface to make the panel glass thinner, and to prevent a decrease in the contrast of the display screen caused when the panel glass is made thinner or an antireflection film is formed. it can. Further, since it is not necessary to switch the material of the panel glass, the above-mentioned effect can be obtained without lowering the productivity. In addition, since the antireflection film and the antistatic film are provided on the filter substrate, light reflected from the panel surface of the display device can be suppressed, and static electricity is generated on the panel surface of the display device. Can be prevented. In addition, since the material of large panel glass can be unified to clear glass,
It has great industrial advantages.

Example (1) Preparation of a Functional Film A transparent polyethylene terephthalate (PET) film having a thickness of 100 μm was used as a filter substrate, and a hard coat layer was applied on one side to secure a surface hardness. Formed. An ITO film having a thickness of 120 μm was formed on the upper surface by a sputtering method to form an antistatic film, and a silicon oxide film having a thickness of 70 μm was formed by a sputtering method to form an antireflection film. An antifouling film was formed on the upper layer with a perfluoro group-containing coating agent. Thus, a functional film was formed.

(2) Formation of Adhesive Layer Next, on the other surface of the film substrate, an acrylic adhesive adjusted to have a transmittance of 50% by adding a dye was applied to a film of 50 ± 2 μm. Thick and evenly applied, then 60 ° C
To form an adhesive layer having a predetermined adhesive strength. By the above, formed on the adhesive surface of the filter substrate,
A display device filter having an adhesive layer having a function of adjusting the transmittance of visible light to a predetermined value was formed.

(3) Lamination Next, using a clear glass panel for a CRT (EIAJ H-8601) polished by a conventional method, assembling it as a CRT, and pressing the display device filter formed above with a rubber roller. Was applied to the panel surface of the CRT from one end, and the adhesive layer was solidified by irradiation with ultraviolet rays to produce a CRT display device.

(4) Performance Evaluation The transmittance of the CRT display device for display light was calculated as follows.

The transmittance (95.5%) reduced by the transmittance of the antireflection film (97.0%) × the transmittance of the adhesive layer (50.0%) × the amount of reflection (4.5%) on the back surface of the glass panel. %) =
46.3% (Equation 1)

In the above calculations, the reflections at the interface between the functional film and the adhesive layer and at the interface between the adhesive layer and the panel surface were considered to be negligible because the difference in refractive index between the two was very small.

As described above, the transmittance difference (E) between the center portion and the end portion of the display panel surface, which cannot be avoided due to the mechanical strength of the CRT in which the transmittance is adjusted by the conventional glass panel.
28-inch flat panel CRT using IAJ H-5702 glass
In this case, the difference in thickness of the panel glass is 3.5 mm, which is about 9% in the difference in transmittance.)
An RT display was obtained.

The present invention is not limited to the above embodiment. For example, the filter for a display device of the present invention can be applied not only to a CRT but also to a display device having such a CRT or to all display devices having a panel on which an image is projected. Others
Various modifications can be made within the scope of the present invention.

[0053]

According to the filter for a display device of the present invention,
The mechanical strength of the display device can be enhanced by using it by bonding it to the display panel surface of a display device such as a CRT. In a CRT, the panel glass can be thinned to reduce the weight of the display device. In addition, it is possible to prevent a decrease in the contrast of the display screen caused when the panel glass is thinned or an antireflection film is formed. Further, since it is not necessary to switch the material of the panel glass, the above-mentioned effect can be obtained without lowering the productivity.

According to the display device of the present invention, the CRT
By reducing the thickness of the panel glass by bonding to the panel surface, the weight of the display device can be reduced, and a decrease in the contrast of the display screen caused when the panel glass is thinned or an antireflection film is formed can be prevented. . Further, since it is not necessary to switch the material of the panel glass, the above-mentioned effect can be obtained without lowering the productivity.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a display device filter according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of a display device according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Display device filter, 11 ... Functional film, 12 ...
Adhesive layer, 14 antifouling layer, 15 antireflection film, 16 antistatic film, 17 hard coat layer, 18 substrate, 21 panel, 22 funnel, 23 neck, 24 electron gun, 25 ... color selection mask, 26 ... fluorescent screen, 27 ... magnetic shield, 28 ... electron beam, 29 ... tension band,
30: mounting ear, 31: conductive tape, 32: ground.

Claims (11)

[Claims] 1. A display device filter for bonding to a display panel surface of a display device to enhance the mechanical strength of the display device, wherein the filter substrate is bonded to the display panel surface of the filter substrate. An adhesive layer formed on the surface and having a function of adjusting the transmittance of visible light to a predetermined value. 2. The filter for a display device according to claim 1, wherein said adhesive layer has a function of adjusting said visible light transmittance to a predetermined value by containing at least a dye or a pigment. 3. The filter for a display device according to claim 1, wherein an antireflection film is formed on a surface of said filter substrate opposite to a surface on which said adhesive layer is formed. 4. The filter according to claim 3, wherein the antireflection film is formed of two or more layers. 5. The filter for a display device according to claim 1, wherein an antistatic film is formed on a surface of said filter substrate opposite to a surface on which said adhesive layer is formed. 6. A display device in which a filter for enhancing the mechanical strength of a cathode ray tube is adhered to a display panel surface of a cathode ray tube having an inner surface having a fluorescent screen irradiated with an electron beam emitted from an electron gun. A display device, wherein an adhesive surface of a filter base material of the filter and a display panel surface of the cathode ray tube are bonded by an adhesive layer having a function of adjusting visible light transmittance to a predetermined value. 7. The display device according to claim 6, wherein a display panel surface of said cathode ray tube is substantially flat. 8. The display device according to claim 6, wherein the adhesive layer has a function of adjusting the transmittance of the visible light to a predetermined value by containing at least a dye or a pigment. 9. The display device according to claim 6, wherein an anti-reflection film is formed on a surface of the filter substrate facing the bonding surface. 10. The display device according to claim 9, wherein said antireflection film is formed of two or more layers. 11. The display device according to claim 6, wherein an antistatic film is formed on a surface of the filter substrate facing the bonding surface.