KR102455580B1 - Display Device - Google Patents

Abstract

The present invention relates to a display device including a light-shielding pattern that does not visually have a sense of heterogeneity with respect to a display area in a structure having a borderless structure. It is possible to improve the appearance quality by eliminating the difference in the visual perception between regions by matching the visual perception caused by the reflection of the shading pattern and the reflection of the shading pattern.

Description

Display Device {Display Device}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly, to a display device including a light blocking pattern that does not visually have a sense of heterogeneity with respect to a display area in a borderless structure.

As the information society develops, the demand for display devices is also increasing in various forms. In response, various display devices such as LCD (Liquid Crystal Display Device), OLED (Organic Light Emitting Display Device), PDP (Plasma Display Panel), ELD (Electro Luminescent Display), and VFD (Vacuum Fluorescent Display) have been studied. Some are already used as display devices in various equipment.

Among them, a liquid crystal display (LCD) and an organic light emitting display (OLED) have recently been developed in response to user needs with advantages of light, thin, compact and vivid colors.

The display device as described above includes a thin film transistor array substrate including a thin film transistor, which is a switching element formed in each pixel area in common. On the thin film transistor array substrate, a thin film transistor is formed at the intersection of each gate line and data line, along with a plurality of gate lines and data lines crossing each other. Here, a portion of the edge of the thin film transistor array substrate is connected to a printed circuit board that transmits an electrical signal to a pad portion connected to each line in order to apply a signal to the gate lines and data lines.

Hereinafter, a conventional display device will be described with reference to the drawings.

1 is a front view of a conventional display device.

As shown in FIG. 1 , the conventional display device has a configuration in which an internal configuration is not visible by enclosing a support structure around the edge of the display surface.

In addition, the mechanism is formed of a material different from that of the display surface, for example, by molding plastic having a certain rigidity, and protrudes from the display surface. It was formed to have a sufficient width, and it became a cause of reducing the actual display effective area.

In addition, the device has its own thickness and is formed to have a sufficient thickness and width to prevent side exposure of the printed circuit board, which increases the thickness of the entire display device, which is a factor hindering slimming.

SUMMARY OF THE INVENTION The present invention has been devised to solve the above problems, and it is an object of the present invention to provide a display device including a light blocking pattern that does not visually have a sense of heterogeneity with respect to a display area in a borderless structure.

In order to achieve the above object, the display device of the present invention provides a light blocking pattern on the back side of the thin film transistor substrate in a borderless structure by providing luminous compensation, so that the luminance displayed by the reflection of the metal reflection and the light blocking pattern in the active region is perceived. By matching, it is possible to improve the appearance quality by eliminating the difference in visual perception between regions.

For this purpose, the display device of the present invention has a rear surface and an inner surface, each planarly divided into an active area and a peripheral dead area, a pixel array on the active area on the inner surface, and the pixel array in the dead area a first substrate having a connection line connected to and a pad electrode, the rear surface of which is used as a display surface; A first polarizing plate is included, and a first color coordinate due to reflection of a metal included in the pixel array outside the first polarizing plate and a second color coordinate due to reflection of the light blocking pattern are the same.

The first color coordinate is a color coordinate in which light passing through the first polarizing plate and the first substrate is reflected by a metal included in the pixel array, and the second color coordinate is the light passing through the first polarizing plate. Color coordinates reflected by the light blocking pattern.

The light blocking pattern may include a monomer, a black pigment, a color pigment, and an additive. In this case, the light blocking pattern preferably includes a black pigment and a color pigment in a ratio of 1:8 to 1:30.

In addition, the pigment including the black pigment and the color pigment in the light-shielding pattern is preferably included in an amount of 7.68 wt% to 15 wt% of the total weight of the light-shielding pattern.

In addition, the light blocking pattern preferably has an optical density of 0.5 to 1.0.

Meanwhile, the metal included in the pixel array having the same color coordinate as the color pigment may be a gate line metal closest to the inner surface of the first substrate.

In addition, the metal included in the pixel array may be formed of a multi-layered metal laminate to prevent reflection. In this case, the metal laminate may include a copper layer, an ITO layer, and a MoTi layer.

In addition, the color pigment may be a green pigment or a red pigment.

A second substrate having a color filter array facing the pixel array may be provided under the first substrate.

In addition, a second polarizing plate may be further included under the second substrate.

In this case, the display device further includes a case for accommodating the second polarizing plate, the second substrate, the first substrate, and the light blocking pattern stacked sequentially from the lower side, wherein the printed circuit board connected to the dead area of the first substrate is located inside the case. It is attached, and it is preferable that the rear surface of the first polarizing plate is completely exposed from the case.

The pixel array may further include an organic light emitting diode for each pixel.

The display device of the present invention has the following effects.

The rear surface of the thin film transistor substrate is used as a viewing surface, and no mechanism is provided on the viewing surface to implement a stepless configuration.

In addition, by forming a light-shielding pattern on the inner surface of the thin film transistor substrate for the purpose of covering a dead area where wiring is concentrated, a color pigment is included to match the color of the reflected light by the metal included in the active area and its color coordinates. , it is possible to improve the appearance quality by offsetting the difference in visual perception between regions in the viewing plane.

As a result, it is possible to implement a borderless structure with stepless difference and a sense of unity.

1 is a view of a conventional display device viewed from the front;
2 is a front view of a display device according to the present invention;
3 is a cross-sectional view taken along line I to I' of FIG. 2;
4A and 4B are a plan view and a cross-sectional view of a display device according to a comparative example;
5 is a graph showing color coordinates generated according to the layered form of the metal;
6 is a graph showing a change in color coordinates according to the pigment control of the display device of the present invention;
7 is a graph showing the color change depending on the laminated form of copper, molybdenum alloy, and ITO
8 is a cross-sectional view illustrating a form in which the display device of FIG. 2 is accommodated in a case;
9 is a cross-sectional view according to another embodiment of the present invention;

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Like reference numerals refer to substantially identical elements throughout. In the following description, if it is determined that a detailed description of a known technology or configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, the component names used in the following description are selected in consideration of the ease of writing the specification, and may be different from the part names of the actual product.

FIG. 2 is a front view of the display device of the present invention, and FIG. 3 is a cross-sectional view taken along line I to I' of FIG. 2 .

First, as shown in FIG. 2 , the display device of the present invention has a borderless structure without a mechanical structure protruding from the display surface (viewing surface), and the actual display surface is a dead area on the inner surface of the first substrate 110 . A connection light blocking pattern 115 is printed as a pattern during the array process to cover the connecting wiring and the pad electrode 111 located in the Since there is no protrusion on the surface of the surface, the display surface is smooth, and there is no step on the surface in design, so that the viewer can feel a clean visual feeling.

In addition, the light blocking pattern 115 provided to cover the dead area where the connecting wiring and the pad electrode 111 are concentrated on the inner surface of the first substrate 110 induces reflection provided in the active area, not just the black pigment. By including color pigments to have the same color coordinates as the metal to be used, when the viewer looks at the viewing surface (display surface), the portion where the light blocking pattern 115 is formed does not stand out from the active area.

That is, in general, when a light-shielding pattern is formed using a black pigment that is completely blackened like a black matrix material as the main material, the degree of reflection due to the metal included in the pixel array located in the active area and the color and the luminance seen by the black pigment are different. , the viewer recognizes the part of the shading pattern that looks black.

Accordingly, the display device according to the present invention adjusts the ratio of the color pigment included in the light blocking pattern 115 so that the viewer has the same color due to the reflection by the metal included in the pixel array and the reflection by the light blocking pattern 115 . By recognizing it, color difference between regions is eliminated to prevent deterioration of visual perception.

To this end, as shown in FIGS. 2 and 3 , the display device of the present invention has a rear surface and an inner surface, each of which is planarly divided into an active area AA and a surrounding dead area, and the inner surface has an active area AA. ), a first substrate 110 having a pixel array 250 on it, a connection wire and a pad electrode 111 connected to the pixel array 250 in a dead area, the rear surface of which is used as a display surface; , located in the dead area on the rear surface of the first substrate 110, and having the same color coordinate as the color coordinate due to reflection of metal included in the pixel array outside the first polarizer, the light blocking pattern 115 and the light blocking pattern and a first polarizing plate 121 covering the rear surface of the first substrate including 115 .

When the color coordinates here are described with reference to FIG. 3 , the lower side of the drawing shows a state before being flipped after the manufacturing process to the viewing surface, and the light is emitted from the lower side of the drawing. However, when external light is incident on the pixel array 250 side, the incident light enters the first polarizing plate 117 and the first substrate 110 , so that The metal is met and the same medium is reflected back in the reverse order, that is, in the order of the first substrate 110 and the first polarizing plate 117 .

In the portion of the light blocking pattern 115 , external light enters the first polarizing plate 117 , meets the light blocking pattern 115 , is reflected, and passes through the first polarizing plate 117 .

In the present invention, by adjusting the component ratio of the color pigment included in the light-shielding pattern 115, the reflection luminance is matched in both regions.

In addition, in the illustrated cross-sectional view, the second substrate 120 having a color filter array facing the pixel array 250 is provided under the first substrate 110 . This is a case in which the display device is implemented as a liquid crystal display device, and when the display device is implemented as an organic light emitting display device, the configuration of the lower side from the second substrate 120 may be omitted.

In addition, when a display device is implemented as a liquid crystal display device, a second polarizing plate 121 may be further included under the second substrate 120 .

In addition, when a display device is implemented as an organic light emitting display device, an organic light emitting diode for each pixel may be further included in the pixel array.

Hereinafter, the properties of the material of the light blocking pattern 115 will be examined through experiments in detail. The material of Table 1 described below is an ink material for forming the light-shielding pattern 115. Therefore, the actual light-shielding pattern 115 as a solution component is cured and remains, and the solvent in the components of Table 1 is volatilized and removed do.

In addition, the black pigment and the color pigment remain in the light blocking pattern 115 , and their ratio is the same before and after curing.

Here, the light blocking pattern 115 includes a monomer, a black pigment, a color pigment, and an additive. In this case, the black pigment and the color pigment are included in the light blocking pattern in a ratio of 1:8 to 1:30, and the color pigment is included in a relatively larger amount than the black pigment.

In addition, the pigment including the black pigment and the color pigment in the light-shielding pattern 115 is included to control a color, and it is preferable that 7.68 wt% to 15 wt% of the total weight of the light-shielding pattern 115 is included. .

In the ink materials shown in Table 1 below, in the case of samples 4 and 5, the color difference between the light blocking pattern 115 and the active region did not occur the most. It corresponds to wt%. The light blocking pattern 115 is cured to remove the solvent, and the sum of the black pigment and the color pigment in the actual light blocking pattern 115 corresponds to 7.68 wt% and 9.60 wt% of the total amount of the light blocking pattern 115 . do. That is, the lower limit of the sum of the pigments was selected from a value that does not feel a color difference, and the upper limit of the sum of the pigments is occupied by the remaining monomers, dispersants, additives, etc., except for the pigment, to maintain solidity in the light-shielding pattern. It was decided in consideration of the minimum rain to be done. In any case, since the pigment in the light blocking pattern of the present invention has a lower optical density of the pigment itself than when a black pigment is simply used, the content thereof is increased than that of a general black pigment.

Item Ref #One #2 #3 #4 #5 pigment black 7.5% 7.5% 5.4% 1.8% 1.0% 0.5% color - 1.2% 3.6% 7.2% 8.4% 10.8% dispersant 1.5 1.5 1.5 1.5 1.5 1.5 monomer A 8-15 8-15 8-15 8-15 8-15 8-15 B 35-50 35-50 35-50 35-50 35-50 35-50 E 3-10 3-10 3-10 3-10 3-10 3-10 F 5-12 5-12 5-12 5-12 5-12 5-12 menstruum Butyl cellosolveacetate 15 15 15 15 15 15 additive 10-20 10-20 10-20 10-20 10-20 10-20 OD 0.89@
1.8㎛ 0.8@
1.7㎛ 0.85@
1.6㎛ 0.8@
1.5㎛ 0.7@
1.4㎛ 0.63@
1.3㎛

In Table 1 above, a case in which the main material of the pigment of the light-shielding pattern is a black pigment, and 7.5wt% is included in the total weight of the light-shielding pattern is a comparative example (ref), and the comparative example and the material in which the ratio of the color pigment is gradually increased Each of the five samples on which the light-shielding pattern was formed was subjected to a color test.

Here, except for the content of each pigment, the dispersant, the materials of the monomers A, B, E, and F, the solvent and the additive are 1.5 wt%, 8-15 wt%, of the total weight of the solution ink forming the light-shielding pattern, respectively, Experiments were carried out under the same content conditions as 35-50 wt%, 3-10 wt%, 5-12 wt%, and 15 wt%.

Here, the black pigment is carbon black.

The color pigment includes, for example, a green pigment, for example, in Sample No. 1, the black pigment is 7.5 wt%, and the green pigment is 1.2 wt%, and in Sample No. 2, the black pigment is 5.4 wt%. wt%, green pigment was 3.6wt%, in sample 3, black pigment was 1.8wt% and green pigment was 7.2wt%, in sample 4, black pigment was 1.0wt%, green The content of the pigment was 8.4 wt%, and in Sample No. 5, the black pigment was 0.5wt% and the green pigment was 10.8wt%.

Table 2 below shows colors from Comparative Example to Sample No. 5, going from left to right, and it can be seen that the panel is observed from black to green gradually as the green pigment content increases, gradually going from left to right.

In this case, the color of the currently used monitor is close to that of samples No. 4 and No. 5, and the light blocking pattern of the present invention adopts the content of the color pigment of samples No. 4 and 5, and the black pigment is relatively small. , The color pigment is included in an amount greater than the amount included in the black pigment in the comparative example. In this case, the black pigment and the color pigment are included in the light blocking pattern in a ratio of 1:8 to 1:30, and the color pigment is included in a relatively larger amount than the black pigment.

Here, in the solution ink constituting the light blocking pattern, the main contents of monomers A and B are epoxy-based resins, respectively, and the light blocking pattern 115 is formed by UV curing the solution ink after coating. These are the components that determine the solidity and cohesiveness of

In addition, E, which has a relatively small content among the monomers, is a material for rework improvement, and in some cases, when the light-shielding pattern is printed incorrectly, rework may be required after removal, and it is a material included for ease of use at this time.

In addition, F is a low-viscosity monomer material, and relative to A and B, E and F are monomolecular monomers and may be a low-viscosity material.

In addition, the solvent uses a high boiling point solvent to improve processability, and the solvent is volatilized in the UV curing process and does not remain in the light blocking pattern 115 remaining after the actual curing.

In addition, the additive is, for example, an initiator, a surfactant, an adhesion promoter, or an antistatic agent, and is a material included to add a specific property to the light blocking pattern 115 or to increase reactivity.

In addition, the light blocking pattern 115 has an optical density of 0.5 to 1.0, and the optical density of the black matrix is low, compared to 4.0, because the content of the black pigment is lowered and the content of the color pigment is increased. Relatively lower compared to the case made only of black pigment. However, even in this case, the connection wiring and the pad electrode 111 of the lower dead region may be covered.

On the other hand, the inventors of the present invention observed the degree of reflection caused by the metal provided in the pixel array and the color recognized through it, and observed that when the light blocking pattern is provided with a black pigment, the viewer is identified as follows. And, as shown in the following experiment, it was confirmed that the color difference appeared differently depending on the component of the metal provided in the active region.

4A and 4B are a plan view and a cross-sectional view of a display device according to a comparative example.

As shown in FIGS. 4A and 4B , even when the light blocking pattern 15 is provided and the connection wiring and the pad electrode 11 concentrated in the dead area of the inner surface of the first substrate 10 are provided, the metal included in the active area is reflected and recognized as a color such as purple.

5 is a graph showing color coordinates generated according to a metal layered form.

As shown in FIG. 5 and Table 3, the layered shape or reflective color of the metal included in the active region is changed.

In the case of MoTi/ITO/MoTi lamination, the value of redish (a*-redness) and yellowish value (b*-degree of appearance of yellow) are 11.32 and -16.6, respectively. In this laminated structure, Observed in red and blue.

On the other hand, when Cu/ITO/Mo is stacked, the value (a*) of the redish is -1.01, and the value (b*) of the yellowish is -21.0, and a relatively severe degree of blue is observed.

In addition, in the case of a stack of Mo/IGZO/Mo, the value (a*) of the redish is 3.00, and the value (b*) of the yellowish is -12.93, which is relatively weak blue.

In the case of Mo/ITO/Mo, the value of redish (a*) is 2.60, and the value of yellowish (b*) is -4.63, which is observed to be weaker than the blue level compared to the structure of Mo/IGZO/Mo.

The photo BM (Black Matrix) material has a value of redish and a yellowish value close to 0, and is not biased toward a specific color. When only the pigment is provided, a color difference occurs between the color of the light-shielding pattern and the reflected color of the active region.

As described above, it can be understood that the color difference is due to the metal component included in the active region and the stacking order thereof, and thus the color difference is generated.

The light blocking pattern of the display device of the present invention includes a color pigment in the light blocking pattern so as to have the same color coordinate as the metal included in the active area according to a metal component included in the active area.

6 is a graph illustrating a change in color coordinates according to a pigment control of the display device of the present invention.

6 is an experiment in which the component ratio of the green pigment is gradually increased from 0% (comparative example) to 1.2%, 3.6%, 7.2%, 8.4%, and 10.8%, as tested in Table 1 above. It can be seen that the color tends to be greenish as the content of the pigment increases. In particular, it can be seen that the green pigment shows a color similar to that of the monitor panel between about 8.4% and 10.8%.

a* b* OD thickness comparative example 0.02 -1.44 0.88 1/82 Green pigment 1.2% -0.18 -1.25 0.88 Green pigment 3.6% -0.5 -0.95 0.85 Green pigment 7.2% -0.88 -0.95 0.80 1.50 Green pigment 8.4% -1.16 -0.87 0.70 1.39 Green pigment 10.8% -1.53 -0.45 0.63 1.30 monitor panel -1.20 -0.55 Target

In addition, in Table 4, when the green pigment content is 8.4% and the case where the green pigment content is 10.8%, the redish value (a*) and the yellowish value (b*) of the monitor panel are located. It was confirmed that the same or similar color to the actual monitor panel could be obtained.

On the other hand, in the above experiment, a 23.8-inch monitor panel was used as a standard, and these monitor panels showed a greenish tendency and included green pigments as color pigments in light blocking patterns, but not all models included green pigments and pixel arrays. , that is, the pigment included in the light blocking pattern may be appropriately selected according to the stacked structure of the gate metal included in the active region and closest to the first substrate 110 .

On the other hand, the gate metal may have a stacked structure of three or more, and may have reflective properties of different colors depending on the stacked form or stacked components. By adjusting the content of the color pigment included in the color coordinates of the gate metal, the color coordinates of the final shading pattern are matched to offset the luminous difference for each region in the viewing plane.

Hereinafter, a case in which another pigment is included in the light-shielding pattern will be described.

7 is a graph showing the color change depending on the laminated form of copper, molybdenum alloy, and ITO.

7 and Table 5, depending on the stacking order of copper, molybdenum alloy, and ITO shows a large difference in the luminous reflection.

For example, if the structure is CMI (Cu/MOTI/ITO) and the thickness of each layer is 5800Å/200Å/400Å, the ready value (a*) is -0.93, and the yellowish value (b*) is - It is equivalent to 1.61.

On the other hand, if the CIM (Cu/ITO/MoTi) structure is used and the thickness of each layer is 5800 Å/500 Å/50 Å, the ready value (a*) is 5.65, and the yellowish value (b*) is -6.34 is equivalent to That is, in this case, the redish tendency is relatively large. In this case, the red pigment is included in the light blocking pattern to match the color with the metal CIM (Cu/ITO/MoTi) in the active region.

8 is a cross-sectional view illustrating a form in which the display device of FIG. 2 is accommodated in a case.

As shown in FIG. 8 , looking at the display device together with the case structure, the case ( 200 , the printed circuit board 150 connected to the dead area of the first board 110 may be attached to the inside of the case 200 through a double-sided tape 155 .

In addition, the printed circuit board 150 is connected to the pad electrode 111 located in the dead area of the inner surface of the first board 110 to apply a signal.

In this case, the rear surface of the first polarizing plate 117 is completely exposed from the case 200 to prevent a conventional mechanism from blocking a part of the region of the first polarizing plate.

In this case, the display surface viewed by the viewer is the rear surface of the first substrate 110 , and on the rear surface of the first substrate 110 , the light blocking pattern 115 corresponds to the edge in order to prevent the metal and the pad from being reflected on the edge. to print What is observed at the edge of the actual display surface is the light blocking pattern, and all other parts can be the effective display area. It is also possible to slim the entire display device by omitting a mechanism covering the display surface.

In addition, in the display device of the present invention, the light-shielding pattern is printed on the actual display surface as a pattern, and the first polarizing plate 117 covers the upper portion, so that there is no protruding surface from the surface, so the display surface is smooth and design There is no step difference on the surface, and there is no difference in the visual perception between the active region and the dead region, so that the viewer can feel a clear visual feeling.

9 is a cross-sectional view according to another embodiment of the present invention.

As shown in FIG. 9 , a display device according to another exemplary embodiment of the present invention is implemented as an organic light emitting display device, and includes two or more thin film transistors for each pixel in the active region of the first substrate 110 . A thin film transistor array including a thin film transistor array and an organic light emitting diode array connected thereto and having an organic light emitting diode for each pixel are included, and an encapsulation layer 140 for encapsulating the organic light emitting diode array is provided.

In this case, a separate color filter substrate is not provided, and therefore, only one polarizing plate is provided on the rear side of the first substrate 110 .

Even in this case, the color of the light blocking pattern may be determined in consideration of the reflection luminance of the metal of the thin film transistor array (TFT array) or the organic light emitting diode array (OLED Array) provided in the active region.

On the other hand, the present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications and changes are possible without departing from the technical spirit of the present invention. It will be clear to those of ordinary skill in the art.

110: first substrate 111: connection wiring and pad electrode
115: light blocking pattern 117: first polarizing plate
120: second substrate 121: second polarizing plate
150: printed circuit board 155: conductive tape
200: case 250: pixel array

Claims (14)

It has a rear surface and an inner surface, and is planarly divided into an active area and a surrounding dead area, the inner surface has a pixel array on the active area, and the dead area includes a connection line and a pad electrode connected to the pixel array and a first substrate whose rear surface is used as a display surface;
an organic light emitting diode included in each pixel in the pixel array;
an encapsulation layer provided on an inner surface of the first substrate to cover the pixel array;
a light blocking pattern overlapping the connection line and the pad electrode and positioned in a dead area of the rear surface of the first substrate; and
and a first polarizing plate that contacts and covers the light blocking pattern and the rear surface of the first substrate,
an edge of the encapsulation layer overlaps the light blocking pattern,
The light-shielding pattern includes a black pigment and a color pigment, and includes the color pigment in excess of the black pigment,
A display device having the same first color coordinates due to reflection of metal included in the pixel array and second color coordinates due to reflection of the light blocking pattern outside the first polarizing plate. The method of claim 1,
The first color coordinate is a color coordinate in which light passing through the first polarizing plate and the first substrate is reflected by a metal included in the pixel array,
The second color coordinate is a color coordinate in which light passing through the first polarizing plate is reflected by the light blocking pattern. delete The method of claim 1,
The light blocking pattern includes a black pigment and a color pigment in a ratio of 1:8 to 1:30. The method of claim 1,
In the light blocking pattern, the pigment including the black pigment and the color pigment is included in an amount of 7.68 wt% to 15 wt% of the total weight of the light blocking pattern. The method of claim 1,
The light blocking pattern has an optical density of 0.5 to 1.0. The method of claim 1,
The metal included in the pixel array is a gate line metal closest to the inner surface of the first substrate. 8. The method of claim 7,
The metal included in the pixel array is a display device including a multi-layered metal laminate. 9. The method of claim 8,
A display device including a copper layer, an ITO layer, and a MoTi layer on the metal laminate. 10. The method of claim 9,
The color pigment is a green pigment or a red pigment. delete delete The method of claim 1,
Further comprising a case for accommodating the first substrate having the pixel array and the encapsulation layer on the inner surface,
A printed circuit board connected to the pad electrode provided in the dead area of the first board is attached to the inside of the case,
A rear surface of the first polarizing plate is completely exposed from the case.
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