KR100741112B1 - Filter and plasma display apparatus having the same - Google Patents

Abstract

A filter and a plasma display apparatus having the same are provided to reduce double images by directly attaching the filter on a front surface of the plasma display apparatus. Beads(11) are formed in a spherical or oval shape, in which a transparent bead(11a) is formed around a black bead of a spherical or oval shape. The black bead is colored by black having high absorption to visible rays and the transparent bead is made of a material having high transmittance to visible rays. The beads are uniformly attached on a base film(13). A coating layer(12) of transparent acrylic resin is interposed between the base film and the beads. The coating layer and the transparent beads are made of a material having the same index of refraction.

Description

Filter and plasma display apparatus having same {Filter and plasma display apparatus having the same}

1 is a cross-sectional view schematically showing the configuration of a filter according to a first embodiment of the present invention.

2 is a cross-sectional view schematically showing the configuration of a filter according to a second embodiment of the present invention.

Figure 3 is an exploded perspective view of a plasma display device having a filter according to an embodiment of the present invention.

4 is a cross-sectional view taken along the line IV-IV of FIG.

<Description of Symbols for Major Parts of Drawings>

10, 50: filter 11: bead

11a: transparent beads 11b: black beads

12: coating layer 13: base film

14: black stripe 20: electromagnetic shielding layer

21: film layer 22: adhesive layer

30: antireflection layer 100: plasma display device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter and a plasma display device having a filter. More particularly, the light transmittance of the light generated from the inside is high and the light incident from the outside is blocked, so that the contrast is excellent. The present invention relates to a filter that can be added and a plasma display device having the same.

A plasma display device using a plasma display panel is a flat panel display device that displays an image by using a gas discharge phenomenon, and has various display capabilities such as brightness, contrast, afterimage, and viewing angle as compared to conventional CRT (Cathode-Ray tube). In addition, it has been spotlighted as a next-generation large flat panel display device because of its thin and large display.

However, in the conventional plasma display apparatus, there is a problem in that an image is repeatedly reflected by a refractive phenomenon due to a difference in material between the front substrate of the plasma display panel and the tempered glass filter. In addition, since the tempered glass filter maintains a certain thickness (about 3 mm) to withstand external shocks, there is a problem in that weight and cost increase. In addition, the existing tempered glass filter has a very complicated structure consisting of a complex of films to perform a variety of functions, there was a problem that the manufacturing process is cumbersome and expensive.

SUMMARY OF THE INVENTION The present invention has been made to solve various problems including the above problems, and an object of the present invention is to provide a filter and a plasma display device having a reduced weight, which eliminates dual images, further improves clear room contrast, and reduces weight.

In addition, an object of the present invention is to provide a filter that is reduced in manufacturing cost and easy to manufacture, and a plasma display device having the filter.

In the present invention, to achieve the above object, the base film; A coating layer located on one surface of the base film; A plurality of black beads included in the coating layer; And a black stripe disposed on an upper surface of the base film between each of the black beads and made of a material having a high absorptivity to visible light.

Here, the black bead is preferably located in the coating layer in a state contained in the transparent bead.

Here, it is preferable that the volume of the black bead is in the range of 3.0% to 80.0% with respect to the external volume of the transparent bead.

Here, the average diameter of the transparent beads contained in the black beads is preferably in the range of 3.0㎛ 30.0㎛.

Here, it is preferable that the black bead and the transparent bead have an outer shape of a spherical or ellipsoidal shape.

Here, the black stripe preferably has a width of 3.0㎛ 30.0㎛.

Here, the black stripe preferably has a thickness of 0.1 ㎛ to 10.0 ㎛.

Here, it is preferable that the coating layer includes a pigment or a pigment to control color and transmittance.

Here, it is preferable to further include an antireflection layer located on one side.

Here, the anti-reflection layer preferably includes a hard coating material therein to prevent scratches by external force.

Here, it is preferable to further comprise a hard coating layer disposed on the anti-reflection layer.

Here, it is preferable to further provide an electromagnetic wave shielding layer located on one side.

Alternatively, the electromagnetic shielding layer disposed on one side; An adhesive layer disposed on the electromagnetic shielding layer; And an anti-reflection layer disposed on the adhesive layer.

Here, the filter according to the present invention may further include a near infrared ray blocking layer, a color correction layer, and / or an adhesive layer located on one side.

In addition, the object of the present invention as described above is achieved by providing a plasma display device equipped with a filter having at least one of the above-mentioned features.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail.

1 is a partial cross-sectional view of a filter 10 according to a first embodiment of the present invention.

As shown in FIG. 1, the filter 10 according to the first embodiment of the present invention includes a bead 11, a coating layer 12, a base film 13, and a black stripe 14.

The bead 11 is made in the shape of a spherical or ellipsoid in which a transparent bead 11a is formed around the black bead 11b having a spherical or ellipsoidal shape. The black bead 11b is black with a high absorption rate to visible light, and the transparent bead 11a is made of a material having high transmittance to visible light.

It is preferable that the diameter of the said transparent bead 11a exists in the range of 3 micrometers-30 micrometers, and the volume of the black bead 11b is 3.0% or more of the volume of the whole bead 11 including the transparent bead 11a. It is preferable that it is a size ratio which belongs to the range of 80.0% or less. This is because it is a bead diameter and size ratio that can maximize the clear contrast contrast effect due to light blocking, transmission and diffusion in relation to the size of the discharge cell of the plasma display panel when used in the plasma display apparatus to be described later. to be.

On the other hand, a plurality of beads 11 are arranged and attached to the base film (13). Preferably, the plurality of beads 11 are distributed substantially uniformly on the base film 13.

The coating layer 12 is for attaching the beads 11 to the base film 13 and is made of a material that transmits visible light. Preferably, the coating layer 12 is made of a transparent acrylic resin to solidify the base film 13 and the beads 11 to be fixed to each other in a molten state.

The coating layer 12 and the disease-bearing beads 11a of the beads 11 may be made of a material having the same refractive index. In the case of having the same refractive index as described above, refraction of visible light does not occur at the surface where the transparent beads 11a and the coating layer 12 contact each other.

In the drawing, the thickness of the coating layer 12 is shown to be about half the diameter of the beads 11 so that the coating layer covers only up to half of the beads 11, but is not limited thereto. The thickness of the coating layer 12 may be formed to be substantially the same or thicker than the diameter of the bead 11 to cover.

On the other hand, a dye or a pigment may be added to the coating layer 12. Through this, the color and transmittance of visible light incident from the display device may be adjusted using the coating layer.

The base film 13 is made of a material capable of transmitting visible light, and functions to allow the filter 10 according to the present invention to be directly attached to the front of the display device. That is, it is advantageous to be in close contact with a material such as glass or plastic on the basis of the interface properties, any material can be used as long as it is a transparent material, it is preferable to be made of a flexible material for the convenience of transport and the convenience of the attachment process.

Hereinafter, the base film 13 will be described in more detail. That is, the base film 13 is polyether sulfone (PES), polyacrylate (PAR, polyacrylate), polyether imide (PEI, polyetherimide), polyethylene naphthalate (PEN, polyethyelenen napthalate), polyethylene terephthalate (PET, polyethyeleneterepthalate), polyphenylene sulfide (PPS), polyallylate, polyimide, polycarbonate (PC), cellulose tri acetate (TAC), cellulose acetate propionate (cellulose acetate propinonate (CAP) and the like, and preferably, polycarbonate, polyethylene terephthalate, cellulose tri acetate, polyethylene naphthalate is used.

The base film 13 may be colored to have a predetermined color. Therefore, by adjusting the coloring conditions of the base film 13, it is possible to adjust the transmittance of the visible light of the filter 10 as a whole. For example, when the base film 13 is formed to have a dark color, visible light transmittance is reduced. In addition to this, it is possible to adjust the color of the visible light projected forward. That is, the color of the base film 13 may be given to the user so as to have a color that is easy to be visually felt by the user, and the color may be given to improve the color purity of the display device in which the filter according to the present invention is employed. In addition, the color of the base film 13 may be patterned to correspond to each subpixel of the plasma display panel in which the filter according to the present invention is employed. However, the present invention is not limited thereto, and the base film 13 may be colored in various ways for various color correction of the base film 13.

The base film 13 has a flat plate shape, and the thickness thereof is preferably 50 μm to 500 μm. However, as the thickness of the base film 13 becomes thinner, the effect of preventing scattering during panel breakage is reduced, and the efficiency of the laminating process decreases as the thickness of the base film 13 increases. It is more preferable to have.

The black stripe 14 may be formed to extend in one direction in a direction perpendicular to the drawing. The width of each black stripe is in the range of 3.0 µm to 30.0 µm, and the thickness is preferably in the range of 0.1 µm to 10.0 µm. Since the black stripe 14 has a higher light absorption rate, it is preferable that a color having high brightness and saturation is preferable, and it is particularly preferable that the black stripe 14 is made black. The black stripe 14 may be formed on the base film through a process such as printing.

Filter 10 according to the first embodiment of the present invention having the configuration as described above, as shown by the arrow in FIG. 1 blocks a considerable amount of visible light incident from the rear of the base film and diffuses visible visible The light rays are transmitted mainly forward. In addition, it functions to block most of the visible light incident from the front and not reflect. As a result, bright room contrast is greatly improved.

On the other hand, the filter 10 according to the first embodiment of the present invention having the structure as described above may be manufactured in the following order.

First, black beads are prepared and then coated with a transparent acrylic material to complete the beads. The production of black beads is made by emulsion polymerization (suspension polymerization) which rotates the seed material in a melt containing a polyurethane-based material as a main component, and the process of coating it with an acrylic-based material is also performed in a black melt containing an acrylic material as a main component. It can be made by emulsion polymerization to rotate the beads at high speed.

Next, a filter according to the first embodiment of the present invention is manufactured by forming a black stripe on the base film, applying a bead added coating material on the base film, and solidifying it.

2 is a partial cross-sectional view schematically showing the configuration of a filter according to a second embodiment of the present invention.

As shown in FIG. 2, the filter 50 according to the second embodiment of the present invention further includes an electromagnetic wave shielding layer 20 and an antireflection layer 30 on one surface of the filter 10 of the first embodiment. The electromagnetic wave shielding layer 20 and the anti-reflection layer 30 may be attached to the base film 13 side of the filter 10 of the first embodiment, or may be the bead 11 side as shown in the drawing.

The electromagnetic wave shielding layer 20 shields electromagnetic waves harmful to a human body generated in the display device in which the filter of the second embodiment of the present invention is mounted. The electromagnetic wave shielding layer 20 is formed by stacking one or more metal layers or metal oxide layers, and preferably has a multilayer structure of five to eleven layers. In particular, when the metal oxide layer and the metal layer are laminated together, the metal oxide layer has an advantage of preventing oxidation or deterioration of the metal layer. In addition, when the electromagnetic wave shielding layer 20 is stacked in multiple layers, the surface resistance value of the electromagnetic wave shielding layer 20 may be corrected as well as the visible light transmittance may be adjusted.

The metal layer may include palladium (Palladi μm), copper, platinum, rhodium (Rhodi μm), aluminum (Al μmini μm), iron, cobalt, nickel, zinc, ruthenium μm, tin, Tungsten, iridium (Iridi μm), lead, silver (Ag), and the like may be formed using each or in combination.

As the metal oxide layer, tin oxide, indium oxide, antimony oxide, zinc oxide, zirconium oxide, titanium oxide, magnesium oxide, silicon oxide, aluminum oxide, metal alkoxide, indium tin oxide, ATO and the like can be used.

The electromagnetic wave shielding layer 20 forms a film layer 21 on the front surface of the filter 10 of the first embodiment, and then uses a method such as sputtering, vacuum deposition, ion plating, CVD, PVD, or the like. Can be formed.

The metal layer or the metal oxide layer has a function of shielding near infrared rays as well as an electromagnetic wave shielding function. Therefore, the problem that the malfunction of peripheral electronic devices occurs due to near infrared rays is reduced.

The shape of the electromagnetic wave shielding layer 20 is not limited to the above, and may be formed in a mesh shape using a conductive metal.

The anti-reflection layer 30 functions to scatter external incident light from the surface and to prevent the surrounding environment of the filter from shining on the surface of the filter. When the antireflection layer is formed on the conventional tempered glass filter, there is a disadvantage in that the sharpness of the image is much lowered between the front substrate and the tempered glass filter. Therefore, the antireflection layer cannot be applied to the conventional tempered glass filter. However, since the filter 50 according to the second embodiment of the present invention is directly attached to the front surface of the display panel, the anti-reflection layer 30 may be applied since the image sharpness problem hardly occurs.

Meanwhile, the filter according to the second embodiment of the present invention preferably includes a hard coating material (not shown) inside the antireflection layer 30. The display device to which the filter 50 according to the second embodiment of the present invention is applied may receive various types of external force during operation, and there is a risk of scratching. Therefore, by including a hard coating material in the anti-reflection layer 30, the scratch by the external force is prevented. However, although the hard coating material may be included in the anti-reflection layer 30, an additional hard coating layer (not shown) may be further formed on the anti-reflection layer 30.

Preferably, the hard coating material includes a polymer as a binder, and an acrylic, urethane, epoxy, and siloxane polymer may be used, or an ultraviolet curable resin such as an oligomer may be used. This may further include a silica-based filler in order to improve the strength (hardness).

Preferably, the anti-reflection layer 30 has a thickness of 2.0 μm to 7.0 μm and a pencil hardness of 2H to 3H, but the present invention is not limited thereto.

Meanwhile, an adhesive layer 22 may be further formed between the electromagnetic shielding layer 20 and the anti-reflection layer 30. The adhesive layer 22 functions to improve adhesion between the two layers between the electromagnetic shielding layer 20 and the anti-reflection layer 30. In addition, an adhesive layer (not shown) may be further disposed on the bottom of the filter 10 according to the first embodiment to secure adhesiveness with the front surface of the display panel. In order to reduce the dual image phenomenon, the pressure-sensitive adhesive layer 22 is preferably such that the difference in refractive index between the pressure-sensitive adhesive layer 6 and the display panel does not exceed a predetermined value, for example, 1.0%.

The adhesive layer 22 preferably includes a thermoplastic and UV curable resin. For example, the acrylate resin may be a pressure sensitive adhesive (PSA). The adhesive layer 22 may be formed using a dip coating method, an air knife method, a roller coating method, a wire bar coating method, a gravure coating method, or the like.

The adhesive layer 22 may further include a compound that absorbs near infrared rays. Such compounds include resins containing copper atoms, resins containing copper compounds or phosphorus compounds, resins containing copper compounds or THIO urea derivatives, resins containing tungsten compounds, cyanine compounds, and the like. Can be.

In addition, the adhesive layer 22 may further include a pigment such as a dye or a pigment to block neon light and perform color correction. The dye performs a function of selectively absorbing light having a wavelength of 400 to 700 nm, which is a visible light region. In particular, when the plasma display panel is discharged, unnecessary visible light is generated at about 585 nm wavelength by neon, which is a discharge gas. In order to absorb the visible light, cyanine-based, squary-based, and azomethine-based systems are used. Compounds such as xanthene, oxo, and azo may be used. The pigment is used as the fine particles to be included in the adhesive layer 22 in the form of a dispersion.

On the other hand, the filter 50 of the second embodiment of the present invention may optionally further include a near infrared blocking layer (not shown) and / or a color correction layer (not shown). The near-infrared blocking function may also be achieved by the above-described electromagnetic shielding layer or adhesive layer, but if necessary, an additional layer may be added to enhance the near-infrared blocking function. The color correction layer is used when the color purity of visible light incident from the display device to which the filter according to the present invention is applied is low, or when it is necessary to correct the color temperature.

In the case of the filter 50 according to the second embodiment of the present invention having the above structure, the transmittance may have 30.0% or more. In addition, the filter 50 may have a haze of less than 5.0%.

3 shows a plasma display device 100 having a filter 10 according to a first embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 3.

The plasma display apparatus 100 includes a plasma display panel 150, a chassis 130, and a circuit unit 140. The filter 10 according to the present invention is attached to the front surface of the plasma display panel 150. Adhesive means such as double-sided tape 154 may be used to couple the plasma display panel 150 and the chassis 130, and the heat conductive member 153 may be configured to dissipate heat emitted during operation in the plasma display panel through the chassis. ) May be disposed between the chassis 130 and the plasma display panel 150.

The plasma display panel 150 implements an image by gas discharge, and includes a front panel 151 and a rear panel 152 coupled to each other.

The filter 10 may be attached to an entire surface of the plasma display panel 150 by an adhesive layer (not shown). Although the present invention is described with reference to the filter 10 of the first embodiment, various types of modified filters reflecting the features of the present invention including the filter 50 of the second embodiment are not limited to the filter of the first embodiment. .

The electromagnetic wave of the plasma display panel 150 is blocked by the filter 10, and the glare phenomenon is reduced. In addition, infrared rays or neon lights may be blocked. In addition, since the filter 10 is substantially attached directly to the front surface of the plasma display panel 150, the problem of dual images is fundamentally solved.

In addition, compared to the conventional tempered glass filter, the weight is reduced, and the cost is reduced.

The chassis 130 is disposed behind the plasma display panel 150 to structurally support the plasma display panel 150. The chassis 130 is preferably formed of aluminum, iron, or the like, which is a metal material having excellent rigidity, or formed of plastic.

The thermal conductive member 153 is disposed between the plasma display panel 150 and the chassis 130. In addition, a plurality of double-sided tapes 154 are disposed around the heat conductive member 153, and the double-sided tapes 154 secure the plasma display panel 150 and the chassis 130 to each other.

In addition, a circuit unit 140 is disposed behind the chassis 130, and a circuit for driving the plasma display panel 150 is wired in the circuit unit 140. The circuit unit 140 transmits an electrical signal to the plasma display panel 150 by signal transmission means. As a signal transmission means, a flexible printed cable (FPC), a tape carrier package (TCP), a chip on film (COF), or the like may be selected and used. According to the present embodiment, the FPCs 161 are disposed on the left and right sides of the chassis 130 as signal transmission means, and the TCPs 160 are disposed on the upper and lower sides of the chassis 130 as signal transmission means. .

On the other hand, in the above description of the example in which the filter according to the present invention is applied to the plasma display device has been described only limited, the filter according to the present invention can be used attached to the front of the various display devices.

In the filter according to the present invention and the plasma display device having the same, since the filter is directly attached to the front surface of the display panel, the dual image can be reduced, and the weight is reduced because it is formed using a relatively thin base film. Reduced, and transmittance is improved. In particular, a large number of beads containing black beads are uniformly distributed therein, so that the effect of diffusing the internal light and the reflection blocking of the external light is large and the clear room contrast is greatly improved. In addition, the manufacturing process is simple and the manufacturing cost is reduced.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (17)

Base film; A coating layer located on one surface of the base film; A plurality of black beads fixed to the upper side of the base film by the coating layer and made of a black color having a high absorption rate to visible light; And And a black stripe disposed on an upper surface of the base film between each of the black beads and made of a material having a high absorption rate to visible light. The method of claim 1, The black bead is a filter, characterized in that located in the coating layer contained in the interior of the transparent bead. The method of claim 2, The volume of the black beads relative to the external volume of the transparent beads is in the range of 3.0% to 80.0%. The method of claim 2, The filter, characterized in that the average diameter of the transparent beads contained in the black bead is in the range of 3.0㎛ 30.0㎛. The method of claim 2, The black bead and the transparent bead is characterized in that the outer shape has a spherical or ellipsoidal shape. The method of claim 1, The black stripe is characterized in that the filter has a width of 3.0㎛ 30.0㎛. The method of claim 6, The black stripe is characterized in that the filter having a thickness of 0.1㎛ 10.0㎛. The method of claim 1, The coating layer comprises a pigment or a pigment, characterized in that the filter to adjust the color and transmittance. The method of claim 1, A filter, characterized in that it further comprises an antireflection layer located on one side. The method of claim 9, The anti-reflection layer is a filter, characterized in that it comprises a hard coating material therein to prevent scratches by external forces. The method of claim 9, And a hard coating layer disposed on the anti-reflection layer. The method of claim 1, The filter further comprises an electromagnetic shielding layer located on one side. The method of claim 1, An electromagnetic wave shielding layer disposed at one side; An adhesive layer disposed on the electromagnetic shielding layer; And And an antireflection layer disposed on the adhesive layer. The method of claim 1, A filter, characterized in that it further comprises a near-infrared blocking layer located on one side. The method of claim 1, The filter further comprises a color correction layer located on one side. The method of claim 1, And a pressure-sensitive adhesive layer disposed on one side of the base film to secure adhesiveness with the display device. A plasma display device comprising the filter of any one of claims 1 to 16.

Images