KR20050015880A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: An LCD(Liquid Crystal Display) is provided to improve light utilization efficiency by reducing reflectivity on a display area of an LCD panel, to thereby enhance display quality of the LCD. CONSTITUTION: An LCD includes a touch panel(600), an LCD pane(500), a light supply unit(900), and an anti-reflecting member(700). The touch panel includes the first substrate and the second substrate, which are combined with each other having a predetermined distance between them and detects position information corresponding to a contact point of the first and second substrates. The LCD panel includes the first display panel and the second display panel, which are combined with each other, opposite to each other, and displays an image corresponding to the position information using light. The light supply unit generates light and provides the light to the LCD panel. The anti-reflecting member is interposed between the LCD panel and the touch panel to reduce reflectivity on the display area of the LCD panel.

Description

Liquid crystal display {LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device for improving display quality.

In general, a flat panel display (FPD) for displaying an image is widely used in notebook computers, monitors, televisions, mobile terminals, and the like.

A device to which a flat panel display device is applied performs a specific process required by a user by using a keyboard, a mouse, a touch screen panel, or the like, and then displays a result of the execution using the flat panel display device.

The touch panel is provided on the liquid crystal display to detect a touched position when a human hand or an object touches a specific position on the screen, and the embedded software performs a specific process corresponding to the touched position.

There are largely touch panel operation methods such as a contact capacitive method, a resistive film method, an infrared sensing method, an integrated tension measuring method, a surface ultrasonic conduction method, and a piezo effect method. The resistive touch panel is generally used because it is durable, thin, and light against external shocks.

The resistive touch panel is formed by bonding two transparent substrates on which a transparent electrode having a resistive component is formed to face each other. At this time, the two substrates are spaced at a predetermined interval. In both substrates, a voltage is applied to the transparent electrode by a current provided from the outside. Therefore, when the user's hand or a specific object contacts a specific position of the touch panel, the two transparent electrodes come into contact with each other. At this time, the resistance component of each transparent electrode is the same as the parallel connection of the resistance.

That is, since a change in resistance value corresponding to a specific position occurs, a change in voltage occurs due to a current flowing through two transparent electrodes. The degree of change of the voltage can be used to recognize the specific contact point.

The touch panel is provided on the liquid crystal display panel which displays an image. In this case, an air layer is formed between the touch panel and the liquid crystal display panel. The refractive index of the air layer is about 1.0, and the refractive index of the liquid crystal display panel is about 1.5. In the liquid crystal display device, due to different refractive indices of the air layer and the liquid crystal display panel, part of the light is reflected at the interface between the touch panel and the liquid crystal display panel, resulting in light loss, thereby reducing the contrast ratio of the liquid crystal display device.

In order to prevent such light loss, a method of forming a display panel inside the liquid crystal display panel, an anti-reflection (AR) treatment, an anti-glare treatment, and a liquid layer between upper and lower electrodes of the touch panel A method of forming the same has been developed. However, these methods have a problem in that the thickness of the liquid crystal display device is increased and the production cost is increased.

An object of the present invention is to provide a liquid crystal display device for improving display quality.

According to one aspect of the present invention, a liquid crystal display device includes a touch panel, a liquid crystal display panel, a light supply unit, and an antireflection member.

The touch panel has a first substrate and a second substrate spaced apart from each other by a predetermined distance, and detects position information corresponding to a contact point when the first substrate and the second substrate are in contact with each other. The liquid crystal display panel has a first display substrate and a second display substrate which is coupled to the first display substrate so as to face each other, and displays an image corresponding to the positional information using light. The light supply unit generates light and provides the light to the liquid crystal display panel. The antireflection member is interposed between the liquid crystal display panel and the touch panel to reduce the reflectance on the display surface of the liquid crystal display panel.

According to such a liquid crystal display device, the antireflection member can reduce the reflectance on the display surface of the liquid crystal display panel, thereby improving light utilization efficiency and improving display quality of the liquid crystal display device.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention.

1 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the liquid crystal display device 1000 according to the present invention includes a liquid crystal display panel 600 displaying an image using light, a touch panel 600 generating position information, an antireflection member 700, First and second polarizing plates (800, 850) and the light supply unit for generating the light (900).

In more detail, the liquid crystal display panel 500 includes a TFT substrate 100 on which a thin film transistor (hereinafter, referred to as TFT) is formed, and a color filter substrate 200 coupled to face the TFT substrate 100. And a spacer for maintaining a gap between the TFT substrate 100 and the color filter substrate 200, the liquid crystal layer 300 interposed between the TFT substrate 100, and the TFT substrate 100 and the color filter substrate 200. 400 and a first sealant 450 for coupling the TFT substrate 100 and the color filter substrate 200.

Specifically, the TFT substrate 100 includes a first insulating substrate 110 and an array layer 120 on which the TFTs are formed in a matrix form on the first insulating substrate 110.

The first insulating substrate 110 is made of a transparent material, such as glass or quartz, to transmit light incident from the light supply unit 900.

The array layer 120 may include a gate line (not shown) for applying a data signal, a gate line for applying a gate signal, indium tin oxide (ITO), or indium zinc oxide; Hereinafter, a pixel electrode (not shown) made of a conductive oxide film such as IZO and the TFT connected to the data line and the gate line apply and block a signal voltage to the pixel electrode.

A source side TCP (not shown) for applying a data side driving signal to the data line is attached to a source side of the TFT substrate 100, and a gate side TCP (for applying a gate side driving signal to the gate line) is provided on a gate side. Not shown) is attached.

The color filter substrate 200 is provided on the TFT substrate 100. The color filter substrate 200 is formed on the second insulating substrate 210, the second insulating substrate 210, and the color filter layer 220 and the liquid crystal layer, which express a predetermined color using the light. It includes a common electrode 230 for applying a common voltage to 300.

The second insulating substrate 210 is a transparent material for transmitting light, for example, made of a material such as glass or quartz.

The color filter layer 220 blocks the light leaked from the plurality of color pixels 221 and the plurality of color pixels 221 expressing a predetermined color by using the light provided from the outside. Ratio: Black Matrix (222) for improving the C / R (R).

The plurality of color pixels 221 may be formed of RGB color pixels, and one color pixel of the RGB color pixels is positioned in one pixel area.

The plurality of color pixels 221 are generated using a photoresist having pigments or dyes of red, green, and blue colors. The plurality of color pixels 221 apply the photoresist to the second insulating substrate 210 on which the black matrix 222 is formed, and then expose the plurality of color pixels 221 using an exposure and development process. Pattern. At this time, the plurality of color pixels 221 is preferably formed to a thickness of about 1.0㎛ ~ 2.0㎛.

The black matrix 222 surrounds the RGB color pixels and blocks light leaked from the RGB color pixels. The black matrix 222 is formed to correspond to the TFT to prevent the TFT from being exposed to the outside.

The common electrode 230 is formed on the color filter layer 220. The common electrode 230 applies a common voltage to the liquid crystal layer 300. The material of the common electrode 230 is formed of a conductive oxide film such as ITO.

The TFT substrate 100 and the color filter substrate 200 are coupled such that the array layer 110 and the common electrode 230 face each other.

Meanwhile, the liquid crystal layer 300 is interposed between the TFT substrate 100 and the color filter substrate 200. The liquid crystal layer 300 is formed of a nematic liquid crystal whose alignment direction of liquid crystal molecules is continuously twisted 90 degrees with respect to the TFT substrate 100 and the color filter substrate 200.

The spacer 400 is interposed between the TFT substrate 100 and the color filter substrate 200 to maintain a uniform cell gap. In this case, the spacer 400 is formed at the same position as the black matrix 222.

Meanwhile, the first sealant 450 is interposed between the TFT substrate 100 and the color filter substrate 200 in the edge region of the TFT substrate 100. The first sealant 450 has a predetermined height in order to secure a space for forming the liquid crystal layer 300, and the liquid crystal layer between the TFT substrate 100 and the color filter substrate 200. 300) is enclosed.

Meanwhile, the touch panel 600 is provided on the liquid crystal display panel 500. The touch panel 600 includes a first substrate 610, a second substrate 620, a dot spacer 630, and the first and second substrates 610, which face each other and are coupled to each other. And a second sealant 640 that couples 620.

In detail, the first substrate 610 includes a transparent substrate 611 and a first transparent electrode 612 formed on the transparent substrate 611.

The transparent substrate 611 is made of a transparent material, for example, a material such as glass, quartz, and a transparent film. The first transparent electrode 612 is made of a transparent conductive oxide film such as ITO.

The second substrate 620 is provided on the first substrate 610. The second substrate 620 includes an optical film 621 and a second transparent electrode 622 formed on the optical film 621. The second transparent electrode 622 is made of a transparent conductive oxide film such as ITO. The first and second transparent electrodes 612 and 622 receive the same voltage from the outside.

The first and second substrates 610 and 620 are coupled such that the first and second transparent electrodes 612 and 622 face each other, and the first and second transparent electrodes 612 and 622 are predetermined to each other. Spaced apart.

The dot spacer 630 is interposed between the first and second substrates 610 and 620. The dot spacer 630 has a hemispherical shape, and a height thereof is formed to be lower than a gap between the first and second substrates 610 and 620.

When a specific position of the optical film 621 is pressed by a user, the second transparent electrode 622 and the first transparent electrode 612 provided under the optical film 621 contact each other. That is, when a specific position of the optical film 622 is pressed, the regions corresponding to the specific position of the first and second transparent electrodes 612 and 622 maintaining a predetermined interval are in contact with each other.

In this case, since the current flows through the first and second transparent electrodes 612 and 622, the resistance values change at portions where the first and second transparent electrodes 612 and 622 contact each other. Accordingly, the voltage at the portion where the first and second transparent electrodes 612 and 622 are in contact with each other changes, and the position of the portion touched by the user can be determined by the change in the voltage.

Therefore, the user must press the optical film 621 to contact the first and second transparent electrodes 612 and 622. In this case, the dot spacer 630 formed on the first transparent electrode 612 may mitigate an impact when the first and second transparent electrodes 612 and 622 contact.

In addition, the dot spacer 630 has elasticity to provide a repulsive force so that the optical film 621 can be returned to its original position when the user releases contact from the touched portion. The dot spacer 630 is formed of a transparent insulating material so as not to block light transmitted through the liquid crystal display panel 500.

The dot spacer 630 may be formed on the first transparent electrode 612 to be in contact with the second transparent electrode 622, but may be spaced apart from the first and second transparent electrodes 612 and 622. It is desirable to be formed at a smaller height. In particular, the dot spacer 630 is preferably formed to a height of 2㎛ to 10㎛. In this case, the dot spacer 630 may have a length of 10 μm to 80 μm or less in diameter at the lower end portion contacting the first transparent electrode 612.

The second sealant 640 is formed in an edge region of the first substrate 610. The second sealant 640 is formed to correspond to the first sealant 450 and is interposed between the first and second substrates 610 and 620. The second sealant 640 combines the first and second substrates 610 and 620 at predetermined intervals. The height of the second sealant 640 is higher than the height of the dot spacer 630.

The anti-reflection member 700 is interposed between the liquid crystal display panel 500 and the touch panel 600. The antireflection member 700 is made of a colorless transparent curing agent that is cured by ultraviolet (UV). Examples of the antireflection member 700 include a curing agent made of modified acrylate or a curing agent made of modified silicone.

The anti-reflection member 700 prevents the formation of an air layer at the interface between the liquid crystal display panel 500 and the touch panel 600. The refractive index of the antireflection member 700 is about 1.5, and has a refractive index substantially the same as that of the first and second insulating substrates 110 and 210. Therefore, the anti-reflection member 700 reduces the reflectance on the display surface of the liquid crystal display panel 500, thereby improving light utilization efficiency.

The anti-reflection member 700 combines the liquid crystal display panel 500 and the touch panel 600 to integrate the liquid crystal display panel 500 and the touch panel 600. Accordingly, since the durability of the liquid crystal display panel 500 and the touch panel 600 is improved, damage to the liquid crystal display panel 500 and the touch panel 600 due to a drop test or an impact test may be prevented. Can be.

The first polarizer 800 is interposed between the liquid crystal display panel 500 and the light supply unit 900. The first polarizing plate 800 polarizes the light incident from the light supply unit 900 in the first direction and exits the liquid crystal display panel 500.

The second polarizer 850 is provided on the touch panel 600. The second polarizer 850 polarizes the light incident from the upper portion of the touch panel 600 and the light incident from the touch panel 600 in a second direction perpendicular to the first direction and exits the light.

The light supply unit 900 is provided under the first polarizing plate 800. The light supply unit 900 generates light in response to a power supplied from the outside, and provides uniform light to the liquid crystal display panel 500.

2A to 2C are cross-sectional views illustrating a manufacturing process of the liquid crystal display shown in FIG. 1.

2A to 2D, the anti-reflection member 700 is formed by applying an ultraviolet curing agent 70 on the liquid crystal display panel 500 and then curing it.

As shown in FIG. 2A, first, the liquid crystal display panel 500 is completed, and then the ultraviolet curing agent 70 is applied to the upper surface of the liquid crystal display panel 500 using the nozzle 10. In this case, the ultraviolet curing agent 70 is applied to the second insulating substrate 210, the surface opposite to the surface on which the color filter layer 220 is formed.

As shown in FIG. 2B, when an appropriate amount of the ultraviolet curing agent 70 is applied onto the liquid crystal display panel 500, the touch panel 600 is disposed on the liquid crystal display panel 500 and then, The touch panel 600 and the liquid crystal display panel 500 are compressed.

As illustrated in FIG. 2C, ultraviolet rays are irradiated to the upper portion of the touch panel 600 to cure the ultraviolet curing agent 70 and to form the antireflection member 700. In this case, the irradiation amount of the ultraviolet ray is about 2000mj / cm 2 to about 5000mj / cm 2.

After curing the anti-reflection member 700, as shown in FIG. 2D, the first polarizing plate 800 is attached to the TFT substrate 100 of the liquid crystal display panel 500, and the second polarizing plate is attached. The liquid crystal display 1000 is completed by attaching 850 to the second substrate 620 of the touch panel 600.

As described above, according to the present invention, the liquid crystal display device includes an antireflection member interposed between the liquid crystal display panel and the touch panel to reduce the reflectance of the display surface of the liquid crystal display panel. Accordingly, the liquid crystal display device can improve light utilization efficiency and improve the contrast ratio of the liquid crystal display device, thereby improving display quality.

In addition, the antireflection member combines the liquid crystal display panel and the touch panel to integrate the liquid crystal display panel and the touch panel. Accordingly, the liquid crystal display panel and the touch panel can be prevented from being damaged by the drop test or the impact test.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

1 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

2A through 2D are cross-sectional views illustrating a manufacturing process of the liquid crystal display shown in FIG. 1.

<Description of the symbols for the main parts of the drawings>

500: liquid crystal display panel 600: touch panel

700: antireflection member 800, 850: polarizing plate

900: light supply unit 1000: liquid crystal display device

Claims (9)

A touch panel having a first substrate and a second substrate spaced apart from and coupled to the first substrate at a predetermined interval, and for detecting positional information corresponding to the contacted point when the first substrate and the second substrate contact each other; A liquid crystal display panel having a first display substrate and a second display substrate coupled to the first display substrate so as to face each other, and displaying an image corresponding to the position information by using light; A light supply unit generating the light and providing the light to the liquid crystal display panel; And And an anti-reflection member interposed between the liquid crystal display panel and the touch panel to reduce reflectance on the display surface of the liquid crystal display panel. The liquid crystal display of claim 1, wherein the anti-reflection member has the same refractive index as that of the first and second display substrates. The liquid crystal display of claim 1, wherein the anti-reflection member couples the touch panel and the liquid crystal display panel to each other. The liquid crystal display device according to claim 1, wherein the antireflection member is a hardener made of a transparent material cured by ultraviolet rays. The liquid crystal display of claim 4, wherein the anti-reflection member is made of acrylic modified. The liquid crystal display of claim 4, wherein the anti-reflection member is made of silicon modified. The liquid crystal display of claim 1, wherein the antireflection member has a refractive index of about 1.5. The method of claim 1, And a first polarizing member interposed between the liquid crystal display panel and the light supply unit, the first polarizing member for polarizing the light in the same first direction as the polarization axis and emitting the light. The method of claim 8, And a second polarizing member positioned on the touch panel and configured to emit the light by polarizing the light in a second direction perpendicular to the first direction.