KR102337893B1 - High resolution touch sensor - Google Patents

Abstract

transparent substrate; an electrode part including a first electrode part formed on the transparent substrate in a first direction and a second electrode part formed in a second direction crossing the first direction; and an insulating layer between the first electrode part and the second electrode part; and a touch panel including a display part coupled to correspond to the touch panel, wherein the electrode part is at 0 degrees to the pattern part of the pixel of the display part. It relates to a high-resolution touch sensor, characterized in that it is formed with a tilting angle (θ) of 14 degrees.

Description

High resolution touch sensor

The present invention relates to a high-resolution touch sensor.

As computers using digital technology develop, computer auxiliary devices are also being developed, and personal computers, portable transmission devices, and other personal information processing devices use various input devices such as keyboards and mice. to perform text and graphic processing.

However, with the rapid progress of the information society, the use of computers is gradually expanding, and there is a problem in that it is difficult to efficiently drive products only with the keyboard and mouse, which currently serve as input devices. Accordingly, there is a growing need for a device that is simple and has fewer erroneous operations, and that allows anyone to easily input information.

In addition, the technology related to the input device goes beyond the level that meets the general function, and the interest is changing to high reliability, durability, innovation, design and processing related technology, etc. In order to achieve this purpose, information input such as text and graphics is required A touch screen panel has been developed as a possible input device.

A touch screen panel is an input device designed to be built-in or added 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. As an example, when an object such as a finger or a touch pen touches the screen, it is a device that recognizes it as an input signal. Such a touch screen panel has recently been widely installed in mobile devices such as mobile phones, portable multimedia players (PMPs), smart phones, etc., and in addition to navigation devices, netbooks, notebook computers, digital information device (DID) ), desktop computers using touch input support operating systems, IPTV (Internet Protocol TV), cutting-edge fighters, tanks, and armored vehicles are used across many industrial fields.

The touch screen panel is a capacitive type that recognizes an input signal by detecting a change in capacitance, a resistive type that recognizes an input signal by detecting a change in resistance by pressure, and an infrared light emitting device. There are infrared sensing types that recognize input signals based on whether or not infrared rays are blocked using a light receiving element. These various types of touch panels have problems in signal amplification, differences in resolution, difficulty in design and processing technology, It is adopted in electronic products in consideration of optical characteristics, electrical characteristics, mechanical characteristics, environmental resistance characteristics, input characteristics, durability and economic feasibility. type).

In the touch panel, research to form an electrode pattern using a metal rather than an ITO electrode is being actively conducted. In this way, when the electrode pattern is formed of metal, the problem of increasing RC Delay Time that may occur when using the existing ITO electrode can be suppressed, and there are advantages of excellent electrical conductivity and smooth supply and demand. However, when the electrode pattern is formed of metal, there is a problem in that the electrode pattern can be visually recognized by the user, and in particular, there is a problem in that a moire phenomenon occurs due to interference between the pixel pattern of the display and the electrode pattern of the metal. In this regard, Patent Registration No. 10-1482401 discloses a technique for minimizing the moire phenomenon by adjusting the pitch of the electrode pattern and the pitch of the pixels of the display unit at a certain ratio and adjusting the angle of the electrode pattern. , by using a metal mesh electrode of 1 layer, there is a problem that the electrode pitch is larger than that of 2 layers, and by using a bridge electrode, the contact resistance is increased, and the large area and high resolution touch sensor products There is a problem that implementation is difficult.

Registered Patent No. 10-1482401

In order to solve this problem, the present invention suppresses the occurrence of the moire phenomenon and minimizes the dead space to minimize the space ratio occupied by the bezel, and at the same time, the contact resistance (contact resistance) An object of the present invention is to provide a high-resolution touch sensor for realizing a large area and high resolution of the touch sensor through minimization of resistance).

The present invention, a transparent substrate; an electrode part including a first electrode part formed on the transparent substrate in a first direction and a second electrode part formed in a second direction crossing the first direction; and an insulating layer between the first electrode part and the second electrode part; and a touch panel including a display part coupled to correspond to the touch panel, wherein the electrode part is at 0 degrees ( °) to 14 degrees (°) provides a high-resolution touch sensor, characterized in that formed with a tilting angle (θ). According to the present invention, by tilting the electrode part at a predetermined angle based on the pattern part of the pixel of the display part, the occurrence of the moire phenomenon can be suppressed, and the tilting direction may be clockwise or counterclockwise. .

In addition, in the first aspect of the present invention, the electrode portion is preferably formed to have a tilting angle (θ) of 5 degrees (°) to 14 degrees (°) based on the pattern portion of the pixel of the display unit.

Further, in the second aspect of the present invention, it is preferable that the first electrode part includes a Tx line to which a driving signal is supplied, and the second electrode part includes an Rx line that receives electric charges in synchronization with the driving signal.

In addition, in the third aspect of the present invention, the Tx line may be driven by a driving signal supplied from one side of the touch panel to the other side (hereinafter, “first signal driving method”), and with respect to the area of the display unit, It is preferable that the ratio occupied by the non-active area of the touch panel is 30% or less.

In addition, in a fourth aspect of the present invention, the Tx line is driven by a driving signal supplied from one side to the other side of the touch panel and a driving signal supplied from the other side to one side (hereinafter referred to as "second signal driving method") The ratio of the non-active area of the touch panel to the area of the display unit is preferably 6.5% or less, and more preferably, 6.05% or less.

In addition, in the fifth aspect of the present invention, the first electrode part and the second electrode part are preferably formed to have an intersection angle (Φ) of 80 degrees (°) to 100 degrees (°), more preferably may be formed with an intersection angle (Φ) of 90 degrees (°).

According to the second to fifth aspects, the ratio of the space occupied by the bezel can be minimized by minimizing the dead space generated by the tilting of the electrode part while minimizing the moire phenomenon. There are advantages in terms of

Further, in a sixth aspect of the present invention, the first electrode portion preferably includes a plurality of thin metal wires parallel to the first direction, and the second electrode portion includes a plurality of metal wires parallel to the second direction. It is preferable to include a fine metal wire of

Further, in the seventh aspect of the present invention, in the electrode part, the pitch (T) of the electrode patterns constituting the first electrode part and the pitch (T) of the electrode patterns constituting the second electrode part are 35 µm to 80 µm, respectively it is preferable

Further, in the eighth aspect of the present invention, the first electrode portion and the second electrode portion constituting the electrode portion are copper (Cu), aluminum (Al), gold (Au), silver (Ag), titanium (Ti), respectively. , palladium (Pd), chromium (Cr), nickel (Ni), and preferably includes at least one selected from the group consisting of alloys thereof.

According to the sixth to eighth aspects, it is possible to prevent an increase in RC Delay Time that may occur when using the existing ITO electrode, and by not using the bridge electrode, the contact resistance is lowered to increase the area and It enables the realization of a high-resolution touch sensor.

In addition, in a ninth aspect of the present invention, the display unit is a liquid crystal display (LCD), a light emitting diode (LED), an organic light emitting diode (OLED), a quantum dot light emitting diode (Quantum dot Light Emitting Diode; QLED), Plasma Display Panel (PDP), Electrophoretic Display (EPD), and at least one selected from the group consisting of Cathode Ray Tube (CRT) It is preferable to include

In addition, in the tenth aspect of the present invention, the transparent substrate, glass (Glass), polyethylene terephthalate (Polyethylene Terephthalate; PET), polycarbonate (PolyCarbonate; PC), polymethyl methacrylate (Polymethylmethacrylate; PMMA), Polyethylene Naphthalate (PEN), Polyethersulfone (PES), Cyclic Olefin Copolymer (COC), Triacetylcellulose (TAC) film, Polyvinyl alcohol (PVA) Film, polyimide (PI) film, polystyrene (PS), biaxially oriented polystyrene (Biaxially oriented PS containing K; BOPS), and acrylic (Acryl) containing at least one selected from the group consisting of desirable.

According to the ninth and tenth aspects, the high-resolution touch sensor of the present invention can be used in various display panels such as LCD, LED, and OLED, and has flexible and/or non-flexible characteristics. It can be used in combination with the substrate.

In the high-resolution touch sensor of the present invention, the electrode part including the first electrode part and the second electrode part is tilted at a predetermined angle based on the pattern part of the pixel of the display part, thereby suppressing the occurrence of the moire phenomenon, Including a plurality of thin metal wires parallel to each direction, it is possible to prevent an increase in RC Delay Time that may occur when using an existing ITO electrode, and by not using a bridge electrode, the contact resistance ( Contact Resistance), enabling the realization of large-area and high-resolution touch sensors. In addition, the pitch of the fine metal wire is smaller than that of the conventional touch sensor, thereby providing an effect of providing more improved touch sensitivity.

In addition, since the first electrode part and the second electrode part are arranged at a predetermined angle, it is possible to minimize the moire phenomenon and at the same time minimize the dead space that may occur due to the tilting of the electrode part, so that the bezel ( Bezel) provides the effect of minimizing the space ratio, and allows the high-resolution touch sensor of the present invention to be used in various display panels such as LCD, LED, and OLED, and to be used on transparent substrates of various materials. It enables use in combination with a substrate having a flexible and/or non-flexible characteristic.

1 is a cross-sectional view of a laminated structure of a transparent substrate and an electrode unit according to an embodiment of the present invention.
2 is a plan view of an electrode unit according to an embodiment of the present invention.
3 is a schematic explanatory diagram illustrating an example of a partial pixel arrangement pattern of a display unit coupled to a touch panel according to an embodiment of the present invention.
4 is a diagram illustrating touch panel lines according to an embodiment of the present invention.
5 is a diagram illustrating the occurrence of a moire phenomenon.
6A is a diagram illustrating generation of a dead space in a touch panel driven by a first signal driving method.
6B is a diagram illustrating generation of a dead space in a touch panel driven by a second signal driving method.

The present invention relates to a high-resolution touch sensor including a pattern part of a display pixel and an electrode part tilted at a predetermined tilting angle (θ). In the high-resolution touch sensor of the present invention, a touch panel including a first electrode part formed in a first direction and a second electrode part formed in a second direction is coupled to a pattern part of a pixel of the display unit and a predetermined tilting angle (θ). ), it is characterized by minimizing the Moire phenomenon.

The moire phenomenon refers to a phenomenon in which a visual pattern is formed according to the difference in the period when regularly repeating shapes are repeatedly combined several times. Specifically, in FIG. 5 , the display pixel pattern is the electrode pattern It indicates that the Moire phenomenon occurs due to interference with 6 is a diagram illustrating the generation of a dead space. Specifically, FIG. 6A is a diagram illustrating the generation of a dead space in the display unit of the touch panel driven by the first signal driving method. , FIG. 6B is a diagram illustrating generation of a dead space for the display unit of the touch panel driven by the second signal driving method. If the proportion of the dead space is increased, it means that the proportion of the space of the bezel is also increased accordingly.

In the high-resolution touch sensor of the present invention, the first electrode part and the second electrode part include a plurality of thin metal wires parallel to the first direction and the second direction, respectively, and each electrode part has a predetermined intersection angle (Φ) It is possible to minimize the space ratio of the bezel by minimizing the dead space while minimizing the moire phenomenon. Furthermore, the pitch of fine metal wires is smaller than that of the conventional touch sensor, and thus it is possible to provide a more precise sensitivity than the conventional touch sensor.

The high-resolution touch sensor of the present invention may be implemented as touch sensors that may be embedded in a display panel of a display device. For example, each of the touch sensors may be implemented as a capacitance-type touch sensor. Capacitive type touch sensors may be divided into self capacitance type touch sensors or mutual capacitance type touch sensors. In the following embodiments, mutual capacitance type touch sensors have been exemplified, but the present invention is not limited thereto.

Specifically, the high-resolution touch sensor of the present invention, the transparent substrate 10; A first electrode portion 20-1 formed on the transparent substrate 10 in a first direction, and a second electrode portion 20-2 formed in a second direction intersecting the first direction. electrode part 20; and an insulating layer 30 between the first electrode part 20-1 and the second electrode part 20-2; and a display part 40 coupled to correspond to the touch panel. However, the electrode part 20 is characterized in that it is formed with a tilting angle θ of 0 degrees (°) to 14 degrees (°) with respect to the pattern part 50 of the pixel of the display unit.

Hereinafter, the advantages and features of the present invention, and a method for achieving it will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings.

However, the present invention is not limited to the embodiments disclosed below, but may be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

The terminology used herein is for the purpose of describing the embodiments, and is not intended to limit the present invention. In this specification, the singular also includes the plural unless otherwise specified in the phrase.

As used herein, includes and/or comprising refers to the presence or addition of one or more other components, steps, operations and/or elements other than the recited elements, steps, operations and/or elements. It is used in the sense of not being excluded.

As used herein, "dead space" may be used synonymously with "dead space" and "inactive area".

Hereinafter, a preferred embodiment of the present invention is described as “a schematic configuration of a touch sensor” , “a transparent substrate” , “electrode unit” , “display unit” , “electrode tilting angle” , “dead space”, “ The items are classified into "Method for evaluating Moire phenomenon or Visibility evaluation method of electrode pattern" and described in detail as follows.

「Structure of touch sensor」

The high-resolution touch sensor of the present invention includes an electrode unit 20 formed on a transparent substrate 10, wherein the electrode unit 20 is a display unit 40, preferably a pixel of the display unit, more preferably It is characterized in that it is formed with a tilting angle θ of 0 degrees (°) to 14 degrees (°) with respect to the pattern part 50 of the pixel of the display part.

1 is a diagram showing a laminated structure of a transparent substrate 10 and an electrode part 20 according to an embodiment of the present invention, FIG. 3 is a diagram showing touch panel lines according to an embodiment of the present invention, FIG. 4 is a diagram schematically showing the electrode unit 20 and the display unit 40 of the touch sensor of the present invention. 1, 2, and 4, the electrode part 20 of the present invention includes a first electrode part 20-1 formed in a first direction, and a second direction crossing the first direction. may include a second electrode part 20-2 formed of . In addition, the touch panel may be formed by further including a separation layer and/or a protective layer on the electrode part 20 . The first electrode part 20 - 1 may include a Tx line to which a driving signal is supplied, and the second electrode part 20 - 2 may include an Rx line for receiving charges in synchronization with the driving signal. In addition, the Tx driving circuit 20-3 for supplying a driving signal to the Tx line included in the first electrode part 20-1 and the Rx line included in the second electrode part 20-2 are connected to each other. A flexible circuit film (FPCB) including an Rx driving circuit 20-4 for receiving electric charge through the first electrode part 20-1 and a flexible circuit film (FPCB) connected to the second electrode part 20-2 It can be configuration.

The touch panel and the display unit 40 are coupled to correspond to the touch panel, and in this case, the electrode unit 20 included in the touch panel is at 0 degrees with respect to the pixel pattern part included in the display unit 40 . (°) to 14 degrees (°) may be tilted with a tilting angle (θ). A detailed description of the tilting angle θ will be described in “Tilt angle of the electrode part” to be described later.

「Transparent substrate」

In the high-resolution touch sensor of the present invention, the transparent substrate 10 is not particularly limited as long as it serves to provide a base of the electrode unit 20 included in the touch panel, and is not particularly limited, and The transparent substrate 10 used for the touch panel may be used.

Specifically, the transparent substrate 10, in one or more embodiments, glass, polyethylene terephthalate (PET), polycarbonate (PolyCarbonate; PC), polymethyl methacrylate (Polymethylmethacrylate) ; PMMA), polyethylene naphthalate (PEN), polyethersulfone (PES), cyclic olefin polymer (COC), triacetylcellulose (TAC) film, polyvinyl alcohol (Polyvinyl alcohol; PVA) film, polyimide (PI) film, polystyrene (PS), biaxially oriented polystyrene (K-resin containing Biaxially oriented PS; BOPS), and at least one selected from the group consisting of Acryl may include.

"Electrode part"

In the high-resolution touch sensor of the present invention, the electrode unit 20 is not particularly limited as long as it includes a configuration for supplying a driving signal and receiving a charge in synchronization with the driving signal, and is not particularly limited. The configuration of the electrode unit used in the touch sensor may be included.

The electrode part 20 included in the high-resolution touch sensor of the present invention is formed in a first direction and includes a first electrode part 20-1 including a plurality of thin metal wires parallel to the first direction; The second electrode part 20 - 2 is formed in a second direction intersecting the first direction and includes a plurality of thin metal wires parallel to the second direction.

The linearity of each of the fine metal wires is not particularly limited, but is preferably formed in a straight shape.

The first electrode part 20-1 and the second electrode part 20-2 may be separated from each other by an insulating layer 30, and the insulating layer 30 is not particularly limited as long as it is a material capable of electrically insulating. does not The first electrode part 20-1 formed in the first direction and the second electrode part 20-2 formed in the second direction have an intersection angle of 80 degrees (°) to 100 degrees (°) ( Φ), and preferably orthogonal configuration, that is, the intersection angle (Φ) may be 90 degrees (°). If the intersection angle (Φ) is less than 80 degrees (°) or exceeds 100 degrees (°), the Moire phenomenon cannot be minimized and the dead space cannot be minimized as well, so the bezel ( There is a problem in that the space ratio of Bezel) increases.

A plurality of thin metal wires constituting the first electrode part 20-1 may be formed to have a pitch T of 35 μm to 80 μm, and constitute the second electrode part 20-2. The plurality of thin metal wires to be used may be formed with a pitch T of 35 μm to 80 μm. The pitch (T) means a distance between an arbitrary thin metal wire and any one of the thin metal wires most adjacent thereto. When the pitch T of the electrode pattern satisfies the corresponding range, it is possible to provide a touch sensor with improved sensitivity.

The material of the first electrode part 20-1 and the second electrode part 20-2 constituting the electrode part 20 is not particularly limited as long as it can conduct electricity, and is not particularly limited. The material used for the electrode part may be used. Specifically, as a material constituting the electrode part 20, in one or more embodiments, copper (Cu), aluminum (Al), gold (Au), silver (Ag), titanium (Ti), palladium ( Pd), chromium (Cr), nickel (Ni), and may include one or more selected from the group consisting of alloys thereof, preferably copper (Cu).

The line width of the fine metal wires constituting the first electrode part 20-1 and the second electrode part 20-2 may be 2 µm to 7 µm in terms of visibility, preferably 2 µm to It may be 5 μm.

"Display part"

In the high-resolution touch sensor of the present invention, the display coupled to correspond to the touch panel of the present invention is not particularly limited as long as it is a device that displays information for visual or three-dimensional reception, storage, and transmission, and is flexible and/or non-functional. Includes a flexible (Nonflexible) display.

Specifically, the display unit 40 of the present invention, in one or more embodiments, a liquid crystal display (LCD), a light emitting diode (Light Emitting Diode; LED), an organic light emitting diode (Organic Light Emitting) Diode; OLED), Quantum dot Light Emitting Diode (QLED), Plasma Display Panel (PDP), ElectroPhoretic Display (EPD), and Cathode Ray Tube (CRT) It may include one or more selected from the group consisting of.

Specifically, the display unit may include a panel substrate, a pixel electrode disposed on the panel substrate, a pixel defining layer, a display layer, a counter electrode, and an encapsulation layer.

A pixel circuit including a thin film transistor (TFT) may be formed on the panel substrate, and an insulating layer may be formed to cover the pixel circuit. The pixel electrode may be electrically connected to, for example, a drain electrode of the TFT on the insulating layer. A pixel defining layer may be formed on the insulating layer to expose the pixel electrode to define a pixel area. A display layer is formed on the pixel electrode, and the display layer may include, for example, a liquid crystal layer or an organic light emitting layer. A counter electrode may be disposed on the pixel defining layer and the display layer. The opposite electrode may be provided, for example, as a common electrode or a cathode of the image display device. An encapsulation layer for protecting the display panel may be stacked on the opposite electrode.

「Tilt angle of electrode part」

In the high-resolution touch sensor of the present invention, the first electrode part 20-1 formed in the first direction and the second electrode part 20-2 formed in the second direction on the transparent substrate 10 include an insulating film therebetween. , including a touch panel formed with a predetermined intersection angle Φ, and a display unit 40 coupled thereto, including the first electrode unit 20-1 and the second electrode unit 20-2 The electrode unit 20 is tilted with a predetermined tilting angle θ with respect to the pattern unit 50 of the pixel of the display unit.

3 is an embodiment of the present invention, the electrode part 20 including the first electrode part 20-1 and the second electrode part 20-2 of the present invention, the display part 40, and the display part It is a view showing the pattern part 50 of the pixel, and referring to FIG. 3 , the tilting angle θ of the present invention is a display part, preferably a pixel of the display part, and most preferably a pattern part 50 of a display part pixel. It indicates the degree of tilting based on , and based on an imaginary line connecting the pattern part 50 of the display pixel in parallel along the first direction, which may be orthogonal to the second direction, clockwise or counterclockwise It indicates the degree of tilting in the direction.

Specifically, one surface of the pattern part 50 of the pixel of the display unit forms a plurality of pixels parallel to the first direction, and the plurality of pixels are parallel to the first direction of the pattern unit 50 of the pixels of the display unit. It indicates the degree to which one surface is tilted in a clockwise or counterclockwise direction based on an imaginary line connected in the first direction.

The tilting angle θ formed by the electrode unit 20 and the pattern unit 50 of the pixel of the display unit may be 0 degrees (°) to 14 degrees (°), preferably, 5 degrees (°) to It may be 14 degrees (°), and more preferably, 5 degrees (°) to 7 degrees (°). When the tilting angle (θ) exceeds 14 degrees (°), not only the effect of preventing the moire phenomenon is reduced, but also the ratio of the dead space becomes excessively large, so that the space ratio of the bezel is increased. this will increase

「Dead space」

The dead space refers to an inactive area of the touch panel coupled to the display unit when the touch panel is tilted at a predetermined angle with the display unit.

Specifically, in one embodiment of the present invention, as shown in FIG. 6A , when the driving signal is driven by the first signal driving method, a region provided with a fine metal wire of an electrode part that is not supplied with the driving signal and the electric charge are received in synchronization with the driving signal. The region in which the thin metal wire of the electrode part cannot be formed forms an inactive region of the touch panel, that is, a dead space.

As another embodiment of the present invention, as shown in FIG. 6B , in the case of driving by the second signal driving method, compared to the case of FIG. 6A , the area provided with the thin metal wires of the electrode part to which the driving signal is not supplied is reduced. , an inactive area, that is, a dead space, can be minimized.

The ratio of the dead space means the area of the non-active area of the coupled touch panel to the area of the display area of the display unit coupled to the touch panel, preferably the display unit, The ratio is preferably minimized, and the ratio of the dead space that can be significantly formed while preventing the moire phenomenon is, in one embodiment, as shown in FIG. 6A , the first signal driving method In the case of , it is preferably 30% or less, and in another embodiment, as shown in FIG. 6B , in the case of the second signal driving method, it is preferably 6.5% or less, and more preferably, 6.05% or less. When the ratio of the dead space exceeds the above range, as the area occupied by the bezel of the device increases, there is a disadvantage in the reduction of the display area of the display or the miniaturization of the device. do.

「Method for evaluating the Moire phenomenon of electrode pattern or evaluation method for visibility」

In one or more embodiments, the method for evaluating the Moire phenomenon or the visibility evaluation method of a touch panel electrode pattern according to an embodiment of the present invention uses a microscope after attaching the electrode pattern of the electrode part to the upper part of the display to measure (A); quantifying the measured image (B); and measuring the moiré reduction effect through the quantified image (C).

More specifically, in the step (A), after attaching the electrode pattern of the electrode part to the upper part of the display, the superimposed image is measured through a microscope, and the image data is stored.

The step (B) is a step (Ba) of converting the image data measured and stored in step (A) into a frequency form (Ba), filtering the frequency data with a CSF (Contrast Sensitivity Function) (Bb), the filtered frequency It may include a step (Bc) of forming image data by inverse frequency transforming the data, and a step (Bd) of calculating a standard deviation (hereinafter, 'STD') for the image data generated by the inverse frequency transforming.

The step (C) may include a step of re-evaluating visually and adopting the electrode pattern as it is seen that the moiré reduction effect is improved as the STD value calculated in the step (B) is smaller.

In particular, the evaluation method of the present invention relates to a visibility evaluation method for minimizing the moiré phenomenon as well as the visibility of an image formed by overlapping the electrode pattern of the electrode part of the touch panel and the pattern part of the display unit pixel.

In the evaluation method according to an embodiment of the present invention, how much the electrode pattern constituting the electrode part is recognized according to the human visual characteristics, or whether moire by the electrode pattern of the electrode part and the pattern part of the display part pixel is recognized by being recognized By evaluating whether or not , it is possible to derive a correlation between the electrode pattern of the electrode part and the tilting angle (θ), the intersection angle (Φ) and the pitch (T) formed by the pattern part of the pixel of the display unit.

Human vision characteristics represent human recognition (distinguishing) ability and contrast, and may be expressed as spatial frequency. Contrast refers to the difference between the tone of a certain part of the image and the intensity of the tone of another part. The strong contrast of an image means that the difference between the light and dark levels of a specific image is greater than normal. In the visibility of the electrode pattern, the greater the contrast, that is, the more clearly the difference between the strength and weakness of the tone is revealed, the more the distinguishing ability according to the human visual perception characteristic increases in a proportional relationship. That is, it can be seen that the ability to discriminate the contrast according to the human visual perception characteristic cannot be expressed as a single function of the spatial frequency, and the discrimination ability is rather reduced in the highest and lowest frequency domains of the spatial frequency.

Here, a Contrast Sensitivity Function (CSF) will be briefly described.

In the human field of vision, there are a mixture of images with clear boundaries, images with unclear boundaries, and images with many and few contrasts in contrast. Visual acuity refers to the overall ability of our eyes to discriminate between these different types of images. However, all visual acuity charts that have been generally used for visual acuity tests so far are made only with clear boundaries and large differences in contrast.

Therefore, our eye's ability to discriminate images with unclear boundaries and small differences in contrast has been neglected. Contrast sensitivity is the ability of the eye to discriminate images with unclear boundaries and small differences in contrast. The CSF filter is a filter that well reflects the human visual characteristics, and the function used in the CSF filter represents the relationship between the spatial frequency of the grating stimulus and the contrast required to perceive the grating. To measure CSF, we first start with a very low frequency (wide bar) sinusoidal grating, the contrast of which is so low that the grating cannot be seen and appears only as a homogeneous gray field of view. Increase the contrast of the grid slightly, but until people can barely see the bar. This level of contrast is the threshold at which the grid can be seen. To draw the CSF, the threshold is changed to the contrast sensitivity by the relation: contrast sensitivity = 1/threshold. The CSF value is the reciprocal of the threshold value for recognizing the brightness difference, and the larger the CSF value, the easier it is to recognize the brightness change. Therefore, according to various studies, human vision is about 6 to 8 [cpd; cycle per degree] It perceives the brightness change best in the vicinity, and as the frequency increases, the brightness change is not well recognized. That is, the human eye cannot detect changes that occur at relatively low frequencies well, whereas changes that occur at high frequencies can be detected well. By using such a CSF filter, the degree of human visibility of the electrode pattern of the electrode part can be known. In the present invention, by using the contrast sensitivity function (CSF), the degree of discrimination ability by the user of the electrode pattern can be determined. CSF of any one model can be used among the functions for , and it is not necessarily limited to one specific CSF model.

Hereinafter, a method for evaluating electrode pattern visibility according to the present invention will be specifically described.

First, it is a step of storing an overlapping image of the electrode pattern of the electrode portion formed on the touch panel and the pattern portion of the display pixel. In one or a plurality of embodiments, after observing the electrode pattern of the electrode formed on the display through a microscope, the superimposed image data is stored.

Next, it is a step of converting the stored image into a frequency form. Here, the transformation into the frequency form may be performed using a Fourier transform equation.

Next, it is a step of filtering the converted frequency data using a Contrast Sensitivity Function (CSF). Here, CSF is

, wherein ξ and η mean spatial angular frequencies in the X-axis direction and Y-axis direction in two dimensions, respectively, and L means a viewing distance. Here, it means a case where the electrode pattern of the electrode part 20 is visually recognized at a viewing distance L=400 mm, where L is to adjust the viewing distance at a relatively constant ratio according to the size of the pitch T of the electrode pattern. Of course you can.

By frequency-converting the original original image data and multiplying it by a contrast sensitivity function (CSF), it is possible to extract a range of frequencies at which human visual perception characteristics can be recognized.

Next, the filtered frequency data is inversely frequency-transformed to generate image data. Even in this case, the inverse frequency transform may be performed using an inverse Fourier transform.

Next, by obtaining a standard deviation (STD) of the image data generated by the filtered inverse frequency transformation, it is possible to evaluate the reduction characteristics of moiré, etc. due to the combination of the electrode pattern of the electrode part and the display part.

Hereinafter, a process of derivation of a related equation for calculating the standard deviation (STD) will be briefly described.

An appropriate meaning for an image that fits the human visual perception characteristic is that it has a proportional relationship to the image contrast. Although there are many definitions of such contrast, here, it can be defined as a root-mean-square (RMS) as a definition of the most appropriate contrast for an image.

[Equation 1]

Here, N is the number of discrete points in the image, I _n is the intensity level of the n-th point of the image, and I′ included in Equation 1 is defined as can

[Equation 2]

I' in Equation 2 means the intensity over the entire image of the electrode pattern of the electrode part. Here, the value defined as RMS may be defined as a standard deviation (STD) of brightness distributed over the entire image area. The contrast sensitivity function (CSF) has a value of 0 at the point where the frequency is 0, and at this time, the value of the image recognized by humans also becomes 0, so it can be rewritten as the following equation.

[Equation 3]

It can be seen that the value that can be known as the definition of the contrast means the standard deviation (STD). That is, as the definition of contrast, it is possible to know how well the pattern can be distinguished to humans according to the characteristics of human vision through the value of how much difference and contrast to the average value according to the light and dark levels of the image. . Equation 3 is a criterion for visibility and may be referred to as 'visibility'.

The contrast sensitivity function (CSF) already looked at also recognizes the difference in brightness, and distinguishing the change in brightness well means that human discrimination ability can be increased, and the area of spatial frequency is subjected to contrast sensitivity function (CSF) filtering. By filtering the frequency region suitable for human visual perception through It is possible to evaluate the visibility reduction characteristic.

Examples and Comparative Examples

As the contents of Table 1 below, for each display having a pixel pitch of 150 mm x 69 mm and a pixel pitch of 125 μm and a display having a pixel pitch of 132 mm x 64 mm of 70 μm, Examples and Comparative Examples were prepared Thus, the ratio of the dead space area, the Moire quantification evaluation result, and the Moire visual test evaluation result are shown together in Table 1 below.

Experimental example

Dead space evaluation

Dead space evaluation is, after tilting the electrode part film including the first electrode part and the second electrode part on each display to form a constant tilting angle (θ), a first signal driving method, For each of the second signal driving methods, the area of the non-active area of the touch panel, which is generated when combined with the display unit, is expressed as a percentage with respect to the area of the display area of the display unit, and is shown in Table 1 below.

Moire Rating(1)

Moire evaluation (1) was performed by attaching an electrode film including the first electrode part and the second electrode part to the upper part of each display with an adhesive, and measuring the Moire Image through a microscope at a distance of 40 cm from the front, and then the image was obtained by Mathworks Table 1 shows the results of 2D-FFT transformation through Matlab and quantification through CSF filtering.

Moire Rating(2)

Moire evaluation (2) was evaluated by attaching an electrode part film including a first electrode part and a second electrode part to the upper part of each display with an adhesive, and visually observing the film at a distance of 40 cm from the front, and the results are shown in Table 1 below.

[Evaluation standard]

River: Moire strongly poet

Middle: Poet Moire

About: Moire weakly poet

division Display Metal Electorde Dead Space
area ratio Moire measurement result Pixel Pitch
(Green standard, μm) Rx and Tx
Intersection angle (Φ °) Tilt direction Line width [μm] Pitch [μm] Tilt angle (θ, °) 1st signal driving method 2nd signal driving method Moire
Rating(1) Moire
evaluation(2) Example 1 70 90 counterclockwise 2 45 5 10.76 2.12 0.070 approximately Example 2 90 counterclockwise 2.5 45 5 10.76 2.12 0.120 approximately Example 3 90 counterclockwise 2.5 50 7 14.89 2.98 0.060 weak Example 4 90 counterclockwise 2.5 85 10 20.93 4.27 1.420 middle Example 5 90 watch
direction 2.5 45 5 10.76 2.12 0.200 approximately Example 6 85 counterclockwise 2.5 50 7 14.89 2.98 0.126 approximately Example 7 90 counterclockwise 2.5 45 14 28.74 6.04 2.076 middle Example 8 125 90 counterclockwise 2.5 35 5 11.14 2.01 0.010 beauty Example 9 90 counterclockwise 2.5 45 11 23.74 4.47 1.076 approximately Example 10 90 counterclockwise 2.5 55 11 23.74 4.47 0.114 approximately Example 11 90 counterclockwise 2.5 85 9 19.62 3.64 2.36 middle Example 12 90 watch
direction 2.5 50 7 15.42 2.82 0.811 approximately Example 13 95 counterclockwise 2.5 55 11 23.74 4.47 0.076 approximately Example 14 90 clockwise 2.5 55 14 29.82 5.73 2.003 middle Comparative Example 1 70 90 counterclockwise 2.5 45 16 32.57 6.95 5.481 River Comparative Example 2 90 watch
direction 2.5 85 15 30.66 6.49 3.378 River Comparative Example 3 75 counterclockwise 2.5 85 16 32.57 6.95 4.284 River Comparative Example 4 125 90 counterclockwise 2.5 45 15 31.82 6.16 3.406 River Comparative Example 5 90 watch
direction 2.5 85 18 37.77 7.47 6.260 River Comparative Example 6 75 counterclockwise 2.5 85 15 31.82 6.16 4.000 River

Referring to Table 1, in the case of Examples 1 to 14 in which the tilting angle forms 5 degrees (°) to 14 degrees (°), regardless of whether the tilting direction is clockwise or counterclockwise, the moiré phenomenon is It can be seen that the reduction In particular, in the case of Examples 3 and 8, the results of the Moire evaluation (1) were 0.06 and 0.01, confirming that the moire phenomenon was particularly reduced compared to the other examples. In addition, when driving by the first signal driving method, it can be confirmed that the ratio of the dead space is at least 10.76%. In particular, when driving by the second driving method, the dead space (dead space) is formed. ) can be confirmed that the ratio is at least 2.01%, so it can be confirmed that the ratio of the area occupied by the bezel can be minimized.

On the other hand, in the case of the comparative example in which the tilting angle is out of the scope of the present invention, it can be confirmed that the result of Moire evaluation (1) differs by up to 6.25 compared to the example, and as can be seen from the visual evaluation result according to this, moire It can be seen that the phenomenon is strongly recognized. In addition, in the case of driving by the first driving method, it can be seen that the ratio of the dead space compared to the embodiment differs by at most 27.01%p or more, and even by the second driving method, up to 5.35 compared to the embodiment. It can be confirmed that there is a difference of %p or more, and it can be confirmed that the ratio of the area occupied by the bezel is increased compared to the embodiment.

10: transparent substrate
20: electrode part
20-1: first electrode part
20-2: second electrode part
20-3: Tx drive circuit
20-4: Rx drive circuit
30: insulating layer
40: display unit
50: pattern portion of display pixels

Claims (12)

transparent substrate;
an electrode part including a first electrode part formed on the transparent substrate in a first direction and a second electrode part formed in a second direction crossing the first direction; and
A touch panel comprising a; an insulating layer between the first electrode part and the second electrode part;
Including a display unit coupled to correspond to the touch panel,
The electrode part is formed with a tilting angle (θ) of 0 degrees to 14 degrees based on the pattern part of the pixel of the display part,
The first electrode part includes a Tx line to which a driving signal is supplied, and the second electrode part includes an Rx line for receiving charges in synchronization with the driving signal,
The Tx line is driven by a driving signal supplied from one side to the other side of the touch panel,
with respect to the area of the display unit, the ratio of the non-active area of the touch panel to 30% or less; or
The Tx line is driven by a driving signal supplied from one side to the other side of the touch panel and a driving signal supplied from the other side to one side,
With respect to the area of the display unit, the high-resolution touch sensor, characterized in that the ratio occupied by the inactive area of the touch panel is 6.5% or less.
The method according to claim 1,
The high-resolution touch sensor, characterized in that the electrode part is formed with a tilting angle (θ) of 5 to 14 degrees based on the pattern part of the pixel of the display unit.
delete delete delete The method according to claim 1,
The first electrode part includes a plurality of thin metal wires parallel to the first direction, and the second electrode part includes a plurality of thin metal wires parallel to the second direction, High-resolution touch sensor.
The method according to claim 1,
The high-resolution touch sensor, characterized in that the first electrode part and the second electrode part are formed to have an intersection angle (Φ) of 80 degrees to 100 degrees.
8. The method of claim 7,
The high-resolution touch sensor, characterized in that the first electrode part and the second electrode part are formed to have an intersection angle (Φ) of 90 degrees.
The method according to claim 1,
The electrode part, the high-resolution touch sensor, characterized in that the pitch (T) of the electrode pattern constituting the first electrode part and the pitch (T) of the electrode pattern constituting the second electrode part are 35㎛ to 80㎛, respectively.
The method according to claim 1,
Copper (Cu), aluminum (Al), gold (Au), silver (Ag), titanium (Ti), palladium (Pd), chromium (Cr), respectively, the first electrode part and the second electrode part constituting the electrode part , Nickel (Ni), and characterized in that it comprises at least one selected from the group consisting of alloys thereof, a high-resolution touch sensor.
The method according to claim 1,
The display unit includes a liquid crystal display (LCD), a light emitting diode (LED), an organic light emitting diode (OLED), a quantum dot light emitting diode (QLED), and a plasma. A high-resolution touch sensor comprising at least one selected from the group consisting of a display panel (Plasma Display Panel; PDP), an electrophoretic display (EPD), and a cathode ray tube (CRT). .
The method according to claim 1,
The transparent substrate is, glass, polyethylene terephthalate (PET), polycarbonate (PolyCarbonate; PC), polymethyl methacrylate (Polymethylmethacrylate; PMMA), polyethylene naphthalate (Polyethylene Naphthalate; PEN), poly Polyethersulfone (PES), Cyclic Olefin Copolymer (COC), Triacetylcellulose (TAC) film, Polyvinyl alcohol (PVA) film, Polyimide (PI) film, Polystyrene (PS), biaxially oriented polystyrene (K-resin containing Biaxially oriented PS; BOPS), and acryl (Acryl), characterized in that it comprises at least one selected from the group consisting of, a high-resolution touch sensor.

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