KR20230133441A - Display integrated touch sensing device - Google Patents

Abstract

The touch detection device according to the present invention includes a transparent substrate; a touch sensor layer including a touch sensor formed on the transparent substrate; A display layer formed on the touch sensor layer to display an image, wherein the image displayed by the display layer is provided to a user through the transparent substrate, and the user provides a touch input by touching the transparent substrate. do.

Description

Display integrated touch detection device {DISPLAY INTEGRATED TOUCH SENSING DEVICE}

This technology relates to a touch detection device. More specifically, it relates to a display-integrated touch detection device formed integrally with the display.

A touch panel that detects touch input is generally attached to a display device such as LCD (Liquid Crystal Display), PDP (Plasma Display Panel), OLED (Organic Light Emitting Diode), AMOLED (Active Matrix Organic Light Emitting Diode), etc. This is a device that detects touch input from an object such as a touch pen.

Touch panels are widely installed in mobile devices such as mobile phones and tablets, and are also used in user/home appliance electronic products such as navigation systems, laptops, desktop computers using touch input-supporting operating systems, and IPTV (Internet Protocol TV). It is used across almost all industrial fields, including heavy equipment, where users provide input.

Depending on its structure, display devices using the above-mentioned touch screen include touch screen add-on type display devices, touch screen top type display devices (on-cell type), and touch screen built-in display devices (in-cell type). It can be divided into devices.

As a method of detecting a user's touch input using the self-capacitance method, it was common to form electrodes that form an object and a capacitor in a form that extends in one direction.

In a touch screen-attached display device, the display device and the touch screen are manufactured separately and then the touch screen is attached to the top of the display device, so the thickness is thick and the brightness of the display device is dark, which reduces visibility.

The touch screen top type display device is a method of forming the elements that make up the touch screen directly on the surface of the display device's upper substrate (color filter for LCD or encapsulation substrate in the case of OLED). Although the thickness can be reduced compared to the attached type, the existing There is a problem that additional facility investment is required because it cannot be manufactured in the LCD manufacturing process, or that manufacturing costs increase when manufactured with existing facilities.

In addition, when detecting a user's touch input using the self-capacitance method of the prior art, there was a problem in that the sensitivity of detection was low and the flexibility of touch detection was low in various situations.

One of the problems to be solved by the present invention is to solve the difficulties of the prior art described above. In other words, one of the problems to be solved by the present invention is to provide a touch input device that is thin, light, and has a small effect on screen visibility in line with the trend of light, thin, and compact terminals.

Additionally, one of the problems to be solved by the present invention is to provide a touch input device that can flexibly detect touch input depending on the situation.

The touch detection device according to the present invention includes a transparent substrate; a touch sensor layer including a touch sensor formed on the transparent substrate; A display layer formed on the touch sensor layer to display an image, wherein the image displayed by the display layer is provided to a user through the transparent substrate, and the user provides a touch input by touching the transparent substrate. do.

According to one embodiment of the present invention, the display layer includes a TFT layer and a color filter layer, and the color filter layer includes color filters of R, G, and B and a black matrix formed at the boundary of the color filter. And, the touch sensor is formed aligned directly above the black matrix.

According to one embodiment of the present invention, a liquid crystal and a TFT transistor that provides a signal for driving the liquid crystal are located in the TFT layer.

According to one embodiment of the present invention, the TFT transistor is provided with a scan signal and a data signal, and a gate line provided with the scan signal and a source line provided with the data signal are positioned to overlap the black matrix.

According to one embodiment of the present invention, the touch sensor is connected to the touch drive IC through a conductive line, and the conductive line extends directly above and overlaps the black matrix in different planes.

According to one embodiment of the present invention, the conductive line extends in a zigzag manner along the black matrix.

According to one embodiment of the present invention, the conductive line extends in a straight line along the black matrix.

According to one embodiment of the present invention, the touch sensor layer includes a first touch sensor and a second touch sensor, each including a protruding area and a concave area, and adjacent to each other, and the protruding area of the first touch sensor is It protrudes into the concave area of the second touch sensor, and the protruding area of the second touch sensor protrudes into the concave area of the first touch sensor.

According to one embodiment of the present invention, the touch sensor is a self dot type touch sensor.

According to one embodiment of the present invention, the touch sensor is formed on the transparent substrate by directly contacting the transparent substrate.

According to the present invention, it is possible to form a touch sensor with a thin thickness, so that a terminal with a thin thickness can be formed, and a touch sensor with high touch detection sensitivity can be formed.

Figure 1 is a diagram schematically showing a cross section of a display device including a touch sensing layer.
Figure 2 is a diagram schematically showing the display layer.
Figure 3 is a diagram schematically showing a cross section of a TFT layer and a touch sensing layer.
Figure 4 is a top view showing the outline of a touch sensor formed on a transparent substrate.
Figure 5 is a diagram illustrating touch sensors including a first sensor and a second sensor arranged in a column.
Figure 6 is a diagram schematically showing the connection relationship between a touch sensor and a conductive line.
Figure 7(a) is a diagram schematically showing an example of detecting a touch using a self-dot type panel according to this embodiment, and Figure 7(b) shows a user's finger (not shown) on a sensing pad. ) is a diagram illustrating the electrical equivalent circuit when in contact.

Hereinafter, this embodiment will be described with reference to the attached drawings. FIG. 1 is a diagram schematically showing a cross section of a display device including a touch sensing layer 100. Figure 2 is a diagram schematically showing the display layer 200. However, for ease of understanding in FIG. 2 , the color filter substrate (GLS) is omitted, and the stacking order of the TFT layer 210 and the color filter layer 220 is shown upside down.

Referring to FIGS. 1 and 2, the display device includes a touch sensor layer 100 including a transparent substrate (Sub) and a touch sensor 110 (see FIG. 3) formed on the transparent substrate (Sub), and a display layer that displays an image. Includes (200). The image displayed by the display layer 200 is provided to the user through a transparent substrate (Sub), and an object (O) providing a touch input provides a touch input through the transparent substrate (Sub).

In the illustrated embodiment, the first polarizing layer (POLa) polarizes the white light formed by the back light unit (BLU) to form the display layer 200 including the color filter layer 220 and the TFT layer 210. ) is provided. Light passing through the color filter layer 220 and the TFT layer 210 is provided to the user through the touch sensing layer 100, the transparent substrate (sub), and the second polarization layer (POLb). In one embodiment, the polarization direction of the first polarization layer (POLa) and the polarization direction of the second polarization layer (POLb) may be perpendicular to each other at 90 degrees.

The color filter layer 220 includes a color filter substrate (GLS), color filter pixels (P) formed on the color filter substrate, and a black matrix (BM) located at the boundary of the color filter pixels (P). In one embodiment, the color filter pixels (P) may contain a pigment or dye that converts the white light provided by the backlight unit (BLU) into red, green, and blue and transmits it.

The color filter layer 220 may further include a planarization layer (not shown) on top of the color filter pixels and a common electrode (CE) formed on the planarization layer. In one embodiment, the common electrode (CE) may be formed of a transparent conductive material to improve the transmittance of emitted light, and the transparent conductive material may be indium tin oxide (ITO) or indium zinc oxide (IZO). As will be described later, the common electrode CE may provide a liquid crystal driving signal that controls the alignment direction of the pixel electrode 221 (see FIG. 3) and the liquid crystal.

In the TFT layer 210, a liquid crystal (LC) and a TFT 213 that provides a liquid crystal control signal are located. In one embodiment, a liquid crystal is located at a position corresponding to a color filter pixel, and each sub-pixel formed of liquid crystal has a pixel electrode (pixel electrode, 221, see FIG. 3) formed of a light-transmissive electrode as the drain (see FIG. 3) of the TFT (213). 213d, see FIG. 3).

The source line 214s connected to the source 213s of the TFT 213 is connected to the source line 214s. Additionally, a gate line connected to the gate is connected to the gate 213g of the TFT 213. As in the embodiment illustrated in FIG. 2 , the source line 214s and the gate line are disposed in an area where the black matrix BM is formed, thereby improving light transmission efficiency. The color filter layer 220 and the TFT layer 210 are bonded with a sealant, and liquid crystal (LC) is injected to form the display 200.

FIG. 3 is a diagram schematically showing a cross section of the TFT layer (TFT) and the touch sensing layer 100, and FIG. 4 is a top view schematically showing the touch sensor 110 formed on a transparent substrate (Sub). . For ease of understanding and explanation, in FIG. 3 , like FIG. 2 , the order of illustration of the TFT layer 210 and the color filter layer 220 is reversed compared to FIG. 1 . Accordingly, as illustrated in FIG. 3, the object O providing input provides a touch input in the direction of the transparent substrate Sub.

Referring to FIGS. 3 and 4 , the touch sensor 110 is located on the transparent substrate (Sub). The touch sensor 110 may be a self-dot type sensor. The touch sensor 110 is formed by forming a conductive metal film with high conductivity on a transparent substrate (Sub) and then patterning it. The touch sensor 110 is formed on the black matrix BM so that light provided through the pixel P is not blocked.

The object (O, see FIG. 1) and the touch sensor 110 each form one electrode and another electrode of the capacitor. The touch sensor 110 includes a first touch sensor 110a and a second touch sensor 110b, and the first touch sensor 110a and the second touch sensor 110b may be adjacent to each other. The first touch sensor 110a adjacent to each other includes a first protruding area P1 and a first concave area S1, and the second touch sensor 110b includes a second protruding area P2 and a second concave area ( S2).

The first protruding area P1 of the first touch sensor 110a protrudes into the second concave area S2 of the second touch sensor 110b, and the second protruding area P2 of the second touch sensor 110b may be formed to protrude into the first concave area S1 of the first touch sensor 110a. From this, the electrical signal according to the size of the capacitance of the capacitor that the object O forms with the first touch sensor 110a and the capacitance of the capacitor that the object O forms with the second touch sensor 110b is interpolated to determine the size of the touch input. The advantage is that sensitivity can be improved.

Conventionally, the touch sensor was located on the same plane as or above the source line and gate line of the TFT, so the capacitance of the parasitic capacitor was formed to be larger than the capacitance of the capacitor formed by the object and the touch sensor. As a result, there was a problem in that touch detection sensitivity was deteriorated.

However, according to the present invention, as illustrated in FIG. 3, the touch sensor 110 is formed on a transparent substrate (Sub), and the object O provides a touch input through the transparent substrate (Sub). Therefore, compared to the prior art, the distance between the object and the touch sensor is reduced to form a capacitor with a larger capacitance, providing the advantage of obtaining high touch detection sensitivity.

Furthermore, since the touch sensor 110 is formed by patterning a metal film with excellent conductivity as illustrated in FIG. 3, the touch sensor 110 according to this embodiment can obtain excellent touch sensitivity, and as described above, the touch sensor 110 has an opening formed in the area where the pixel P is located, so it does not block the light provided by the pixel P, thereby providing high light transmittance.

The touch sensor 110 is insulated with a transparent insulating layer 120. In one embodiment, the transparent insulating layer 120 may be implemented as one or more of an organic layer and an inorganic layer. A gate 213g is located on the transparent insulating layer 120. In one embodiment, the gate 213g may be formed by forming a metal thin film with good conductivity and then patterning it. Additionally, the gate line may be formed integrally with the gate 213g.

A gate insulating film 212 is located on the gate 213g. In one embodiment, the gate insulating film 212 may be formed of a silicon nitride film (SiNx), and in another example, it may be formed of a silicon oxide film. An active region 213a in which a channel is formed is located on the upper layer of the gate insulating film 212. The active region 213 may be formed of hydrogenated amorphous silicon (a-Si:H).

An upper active area 213' may be located on the upper layer of the active area 213. The upper active region 213' may be doped with impurities to have high conductivity. In the example shown, the upper active region 213' may be doped with n+.

A source 213s and a drain 213d made of metal with excellent conductivity are located in the upper active region 213'. The upper active region 213' is in contact with the source 213s and the drain 213d, and is doped with impurities to have high conductivity, so there is a contact between the source 213s and the upper active region 213' and between the drain 213d and the upper layer. The contact resistance between the active areas 213' can be lowered.

In one embodiment, the source 213s and the drain 213d may be formed of a metal layer and then patterned to cut the metal layer to form the source 213s and the drain 213d. The source 213s is patterned to extend in a desired direction to form a source line 214s, and the drain 213d is patterned to extend in a desired direction to form a drain line 214d. An insulating layer 215 may be located on the upper layer of the source 213s and the drain 213d, and the insulating layer 215 may be a silicon nitride film (SiNx).

The drain line 214d is electrically connected to the pixel electrode 221. The pixel electrode 221 receives a liquid crystal control signal that controls the orientation direction of the liquid crystal (LC) through the TFT 213 and provides the liquid crystal control signal to the liquid crystal (LC). The alignment direction of the liquid crystal (LC) is controlled according to the liquid crystal control signal and controls the light provided from the back light unit (BLU).

A first passivation pattern 216 and a second passivation pattern 217 and 218 may be formed on the insulating layer 215. In one embodiment, the first passivation pattern 216 may be made of a transparent organic material. For example, the first passivation pattern 216 may be made of the same material as the insulating layer that insulates the touch sensor 110. The second passivation patterns 217 and 218 may be formed of a silicon nitride film and a silicon oxide film.

The gate COM electrode 222 may be formed during the formation of the gate 213g. When forming the passivation pattern 216 with the first 6 mask structure, the gate COM electrode 222 and the central COM electrode 223 are connected to respond to high resolution and minimize afterimages, and are used as an overall common electrode structure.

The example shown in FIG. 3 is a structure of a unit pixel (P, see FIG. 1) and a touch sensor 110, and a plurality of the unit pixels (P, see FIG. 1) and touch sensors 110 are arranged in an array to provide touch A display device capable of detection can be achieved.

FIG. 5 is a diagram illustrating the touch sensor 110 including the first sensor 110a and the second sensor 110b arranged in a column C. The column C including the touch sensor 110 illustrated in FIG. 5 may be further disposed toward the side of the column C to form a touch panel. Referring to FIG. 5 , as described above, the touch sensor 110 may include a first sensor 110a and a second sensor 110b adjacent to each other. The touch sensor 110 may be electrically connected to a touch drive IC (not shown) through a conductive line 310 (see FIG. 6).

FIG. 6 is a diagram schematically showing the connection relationship between the touch sensor 110 and the conductive line 310. Referring to FIG. 6 , the conductive line 310 may be formed on the same plane as the touch sensor 110. In one embodiment, the conductive line 310 may be formed together with the touch sensor 110, and may be made of the same excellent conductive metal material as the touch sensor 110. In another embodiment, the conductive line may be formed of transparent conductive materials such as ITO or IZO.

According to the embodiment illustrated in FIG. 6, the conductive line 310 is electrically connected to the touch sensor and may be formed and extended in a straight line in the direction of the touch drive IC (not shown). However, according to an embodiment not shown, the conductive line 310 may be formed and extended in a zigzag manner along the boundary of the pixel P.

Since the illustrated conductive line 310 is made of a metal with good conductivity, excellent touch sensitivity can be obtained by preventing the signal detecting a touch from being attenuated. In addition, the conductive line 310 is formed on the black matrix BM, which is the boundary between the pixels P, so it has the advantage of not blocking the light provided through the pixels P.

FIG. 7(a) is a diagram schematically showing an example of detecting a touch using a self-dot type panel according to this embodiment, and FIG. 7(b) shows a user's finger on one of the sensing pads (SP). This is a diagram illustrating the electrical equivalent circuit when (not shown) is in contact. Referring to FIG. 7(a), the self-dot type panel l0 according to this embodiment includes a plurality of sensing pads SP arranged in an array.

Each sensing pad (SP) is connected to the multiplexer 20 through a conductor, and as illustrated in FIG. 7(a), the sensing pads (SP) form a sensing line in which the sensing pads (SP) are connected in a row by connecting the multiplexer, or as shown in FIG. As in the embodiment that is not shown, a sensing line in which sensing pads SP are connected in rows may be formed.

Hereinafter, for easy understanding and concise and clear explanation, an example will be given of configuring a channel in which sensing pads (SP) are connected to a column (C, see FIG. 5) by a multiplexer (M). However, this does not exclude forming a channel in which sensing pads (SPs) are connected in rows.

As illustrated in FIG. 7(a), touch sensing can perform even-numbered columns (EVEN COL) and odd-numbered columns (EVEN COL). In this way, even-numbered heat sensing and odd-numbered heat sensing can be performed alternately. Additionally, when performing touch detection by alternating between even and odd columns, touch detection can be performed sequentially, such as row 0, row 1, row 2, etc. By performing alternating sensing in this way, touch sensitivity can be improved and current consumption can be reduced.

Figure 7(b) is an equivalent circuit diagram when an input is provided by touching a user's finger to a sensing pad. Referring to FIG. 7(b), the panel l0 includes a pad capacitor (C _D ) formed on the sensing pad (SP), a parasitic capacitor (C _P ), and a finger capacitor (C) between the user's finger and the sensing pad (SP). _F ) is formed. The driving circuit part includes a driving capacitor (C _DRV ).

For touch sensing, the first switch (SW1) is turned on and the pad capacitor (C _D ), parasitic capacitor (C _P ), finger capacitor (C _F ), and driving capacitor (C _DRV ) are pre-charged with the pre-charge voltage (V _PRE ). Carry out the charge. Next, when the first switch (SW1) is cut off and the driving voltage (V _DRV ) is provided through the driving capacitor (C _DRV ) with the second switch (SW2) turned on, the capacitor formed by the user's finger A voltage difference (ΔV _DB ) occurs as shown in Equation 1 above. Therefore, the touch input can be detected by detecting the voltage difference in this way.

Although the present invention has been described with reference to the embodiments shown in the drawings to aid understanding, these are embodiments for implementation and are merely illustrative, and those skilled in the art will be able to make various modifications and equivalents therefrom. It will be appreciated that other embodiments are possible. Therefore, the true technical protection scope of the present invention should be determined by the attached patent claims.

100: Touch sensing layer
110: touch sensor
200: display layer
210: TFT layer
212: Gate insulating film
213:TFT
213s: source
213d: drain
213g: gate
213a: active area
213a': upper active area 214d: drain line
214s: source line
215: insulating layer
216: first passivation pattern
217, 218: second passivation pattern
220: Color filter layer
222: Gate COM
223: MIDDLE COM
310: Challenge Track

Claims (10)

transparent substrate;
a touch sensor layer including a touch sensor formed on the transparent substrate;
It includes a display layer formed on the touch sensor layer to display an image,
The image displayed by the display layer is provided to the user through the transparent substrate,
A touch detection device in which the user provides a touch input by touching the transparent substrate.
According to paragraph 1,
The display layer is,
Includes a TFT layer and a color filter layer,
The color filter layer includes R, G, and B color filters and a black matrix formed at the boundary of the color filter,
The touch sensor is a touch detection device formed by being aligned directly above the black matrix.
According to paragraph 2,
In the TFT layer,
A touch detection device in which a liquid crystal (Liquid Crystal) and a TFT transistor that provides a signal for driving the liquid crystal are located.
According to paragraph 3,
The TFT transistor is provided with a scan signal and a data signal,
A touch detection device in which the gate line to which the scan signal is provided and the source line to which the data signal is provided overlap with the black matrix.
According to paragraph 1,
The touch sensor is,
It is connected to the touch drive IC through a conductive line,
A touch detection device wherein the conductive line is located directly above and extends in a different plane from the black matrix.
According to clause 5,
The challenge line is,
A touch detection device formed of the same material as the touch sensor.
According to paragraph 1,
The touch sensor is,
It is connected to the touch drive IC through a conductive line,
A touch detection device wherein the conductive line is formed of a transparent conductive material.
According to paragraph 1,
The touch sensor layer is,
Each includes a protruding area and a concave area, and includes a first touch sensor and a second touch sensor adjacent to each other,
The protruding area of the first touch sensor protrudes into the concave area of the second touch sensor,
A touch detection device wherein the protruding area of the second touch sensor protrudes into the concave area of the first touch sensor.
According to paragraph 1,
The touch sensor is,
A touch detection device that is a self-dot type touch sensor.
According to paragraph 1,
The touch sensor is,
A touch detection device formed on the transparent substrate by directly contacting the transparent substrate.