TWI637302B - Integrated touch display - Google Patents

Abstract

An integrated touch display includes a composite substrate, a bottom polarizing plate, and a display panel. The display panel is located between the composite substrate and the bottom polarizing plate. The composite substrate includes a quarter-wave plate with a low in-plane retardation (Re), a touch electrode layer, a protective layer, and a polarizing layer disposed on at least one surface of the quarter-wave plate with a low in-plane retardation. The polarizing layer is disposed between the quarter-wave plate with a low in-plane retardation and the protective layer.

Description

Integrated touch display

The invention relates to an integrated touch display, in particular to an integrated touch display including a touch electrode layer disposed on at least one surface of a quarter-wave plate with a low in-plane phase delay.

The laminated structure of the traditional polarizing plate uses polyvinyl alcohol (Polyvinyl Alcohol, PVA) as an intermediate layer, and two sides of the polyvinyl alcohol are Triacetate Cellulose Film (TAC) film layers, and the PVA layer plays a polarizing role. However, the PVA layer is extremely easy to hydrolyze. In order to protect the physical properties of the polarizing plate, a TAC layer with high light transmittance, good water resistance, and a certain mechanical strength needs to be attached to each side of the PVA layer to protect the PVA layer. The touch panel will be superimposed on the polarizer. Because both polyvinyl alcohol and cellulose triacetate have linearly polarized light characteristics, light passes through the laminated structure of a conventional polarizing plate and becomes linearly polarized light. If the polarization direction of this linearly polarized light is perpendicular to the polarization direction of the sunglasses (with linearly polarized light characteristics) worn by the observer, the problem of black screen will occur in the visual effect. When the substrate of the touch panel is plastic, the problem of rainbow effects may occur in the visual effect.

In addition, the thickness of the laminated structure of the conventional polarizing plate is about 75 to 135 micrometers. After bonding with the touch panel, the thickness is about 100 to 250 micrometers. M, if it is matched with module cover glass (CG), its overall thickness can reach 725 microns.

Therefore, there is an urgent need for an integrated touch display that can simultaneously reduce the problem of black screens and rainbow patterns that are visually generated and can reduce the overall thickness.

An embodiment of the present invention provides an integrated touch display including a composite substrate, a bottom polarizing plate, and a display panel, wherein the display panel is located between the composite substrate and the bottom polarizing plate. The composite substrate includes a quarter wave plate with a low in-plane retardation, a touch electrode layer, a protective layer, and a polarizing layer disposed on at least one surface of the quarter wave plate with a low in-plane retardation. The polarizing layer is disposed between the quarter-wave plate with a low in-plane retardation and the protective layer.

In an embodiment of the present invention, it further includes: a protective cover and an optical glue. Optical glue connects the composite substrate and the protective cover.

In an embodiment of the present invention, the in-plane phase delay of the quarter-wave plate with a low in-plane phase delay is less than 300 nm.

In one embodiment of the present invention, the touch electrode layer is a single touch electrode layer.

In one embodiment of the present invention, the single-layer touch electrode layer is disposed between the quarter-wave plate with a low in-plane phase delay and the polarizing layer.

In an embodiment of the present invention, the single-layered touch electrode layer is disposed between the 1/4 wavelength wave plate with a low in-plane phase delay and the optical glue.

In one embodiment of the present invention, the touch electrode layer includes a corresponding first touch electrode layer and a second touch electrode layer. First touch electrode layer The second touch electrode layer is disposed between the 1/4 wavelength wave plate with a low in-plane phase delay and the optical adhesive, and the second touch electrode layer is disposed between the 1/4 wavelength wave plate with a low in-plane phase delay and the polarizing layer.

In an embodiment of the present invention, the thickness of the composite substrate is less than 170 micrometers.

100‧‧‧ quarter wave plate with low in-plane phase delay

102‧‧‧Touch electrode layer

104‧‧‧Single-layer touch electrode layer

106‧‧‧Printed Circuit Board

108‧‧‧ polarizing layer

110‧‧‧ protective layer

112‧‧‧Display Panel

114‧‧‧ bottom polarizer

116‧‧‧Optical glue

118‧‧‧Protection cover

120‧‧‧first touch electrode layer

122‧‧‧Second touch electrode layer

300, 500, 700‧‧‧ composite substrate

200, 400, 600‧‧‧ integrated touch display

In order to make the features, advantages, and embodiments of the present invention more comprehensible, the accompanying drawings are described as follows: FIGS. 1A to 1F are cross-sectional views of an integrated touch display according to an embodiment of the present invention, respectively. .

FIG. 2 to FIG. 3 respectively show different aspects of the integrated touch display according to the embodiment of the present invention.

The purpose and advantages of the present invention will be more remarkable after detailed description accompanying drawings and element symbols in the following embodiments. It should be understood, however, that the embodiments provided are not intended to limit the scope of the invention. These practical details should not be used to limit the invention. That is, in some embodiments of the present invention, these practical details are unnecessary.

The words "including", "including", "having", "containing", "concerned" and other similar meanings used in this article are all open-ended, for example, meaning including but not limited to this.

Unless otherwise clearly stated in the content, Numerals contain plural referents. By referring to a specific reference such as "an embodiment", in at least one of the embodiments of the invention of the present invention, it represents a specific feature, structure or characteristic. When a word appears through a special reference, it is not necessary to refer to the same embodiment. Furthermore, in one or more embodiments, these special features, structures, or characteristics can be combined with each other as appropriate.

In the following, a plurality of embodiments of the present invention will be disclosed graphically. For the sake of clarity, many practical details will be described in the following description. It should be understood, however, that these practical details should not be used to limit the invention. That is, in some embodiments of the present invention, these practical details are unnecessary. In addition, in order to simplify the drawings, some conventional structures and components will be shown in the drawings in a simple and schematic manner.

In addition, relative terms, such as "down" or "bottom" and "up" or "top", are used to describe the relationship between one element and another element shown in the figures in the text. Relative vocabulary is used to describe different orientations of the device beyond those described in the drawings. It is understandable. For example, if the device in a figure is turned over, the element will be described as being on the "lower" side of the other element and will be oriented on the "upper" side of the other element. The exemplified word "down" may include two directions "down" and "up" according to the specific orientation of the drawing. Similarly, if the device in a figure is turned over, the element will be described as "below" or "below" the other element will be oriented "above" the other element. The exemplary words "below" or "below" can include both "above" and "above" orientations.

1A to 1F respectively illustrate an embodiment according to the present invention Sectional view of the integrated touch display.

As shown in FIG. 1A, a quarter wave plate 100 with a low in-plane phase delay is provided. A wave plate is an optical element with birefringence properties. When light passes through this element, the speed of light in which the electric field vibrates in a certain direction (F-axis, fast axis) is faster, while the speed of the electric field in a direction perpendicular to this direction (S-axis, slow axis) is slower. Therefore, when the light in these two directions passes through the optical element, a phase difference is generated. If the phase difference is equal to a quarter wavelength, the optical element is called a quarter-wave plate (QWP). The 1/4 wave plate is controlled by the thickness of this birefringent optical element, and the phase difference between the two electric field vibration directions is related to the wavelength of light passing through this element. In addition, the optical retardation (R) refers to the birefringence multiplied by the thickness of the film, R = Δn × d, where Δn represents the birefringence, and d is the thickness of the optical film. Birefringence is divided into in-plane refractive index △ n _in = n _x -n _y and out-of-plane refractive index △ n _th = n _z- (n _x + n _y ) / 2, where the Z-axis direction is the thickness direction of the optical film The X axis refers to the direction of the maximum refractive index in the plane orthogonal to the Z axis, and the Y axis refers to the directions orthogonal to the X axis and the Z axis. n _z refers to the refractive index of the optical film along the Z axis direction, n _x refers to the refractive index of the optical film along the X axis direction, and n _y refers to the refractive index of the optical film along the Y axis direction. Therefore, the in-plane phase delay is represented by R _e = (n _x -n _y ) × d, and the out-of-plane phase delay is represented by R _th = [n _z- (n _x + n _y ) / 2] × d. In the present embodiment, the optical 1/4 wavelength phase retardation film of low surface 100 refers to in-plane phase retardation R _e is less than 300 nm, for example, in-plane phase retardation R _e is 250,200,150,100 nm . In this embodiment, the quarter-wavelength plate 100 with a low in-plane retardation is made of a cyclic olefin monomer copolymer (Cyclic Olefin Copolymer, COC) or a cyclic olefin monomer polymer (Cyclic Olefin Polymer, COP). ).

Please continue to refer to FIG. 1A again, and set the touch electrode layer 102 on at least one surface of the quarter-wave plate 100 with a low in-plane phase delay. In this embodiment, the touch electrode layer 102 may be a single layer of indium tin oxide (SITO), and is disposed on the quarter-wave plate 100 with a low in-plane phase delay. In some embodiments, the touch electrode layer 102 may be a double indium tin oxide (DITO), and is disposed on opposite sides of the quarter-wave plate 100 with a low in-plane phase delay. In other embodiments, the touch electrode layer 102 is, for example, nano silver wires, nano silver particles, nano carbon tubes, conductive polymers, or metals.

As shown in FIG. 1B, the touch electrode layer 102 is a single touch electrode layer 104, and a laser drill is used to form a patterned single touch electrode layer 104. In some embodiments, the pattern of the single-layer touch electrode layer 104 is, for example, a square, a rectangle, a parallelogram, a triangle, or a trapezoid. Next, the 1/4 wavelength wave plate 100 with a low in-plane phase delay is combined with a flexible printed circuit (FPC) 106, where the printed circuit soft board 106 can be directly fixed at a 1/4 of the low in-plane phase delay Wavelength plate 100.

As shown in FIG. 1C, the printed circuit board 106, the quarter-wave plate 100 with a low in-plane phase delay, and the single-layer touch electrode layer 104 are flipped up and down to make the single-layer touch electrode layer 104 is located below the quarter-wave plate 100 with a low in-plane phase delay. Next, a polarizing layer 108 is bonded under the single-layer touch electrode layer 104 so that the single-layer touch electrode layer 104 is located between the quarter-wave plate 100 and the polarizing layer 108 with a low in-plane retardation. Next, a protective layer 110 is bonded under the polarizing layer 108 so that the polarizing layer 108 is set at a quarter-wavelength with a low in-plane retardation. Between the wave plate 100 and the protective layer 110, a composite substrate 300 is formed. In this embodiment, the material of the polarizing layer 108 is polyvinyl alcohol (PVA), and the material of the protective layer 110 is cellulose triacetate (TAC). The thickness of the composite substrate 300 provided in this embodiment can be controlled below 170 micrometers (μm). Therefore, compared with the laminated structure of a conventional polarizing plate, the composite substrate 300 provided in this disclosure is thinner.

As shown in FIG. 1D, the display panel 112 and the bottom polarizing plate 114 are sequentially attached under the composite substrate 300 so that the display panel 112 is located between the composite substrate 300 and the bottom polarizing plate 114. Next, the printed circuit board 106 is removed to form an integrated touch display 200. In this embodiment, the substrate of the touch electrode has been integrated into the composite substrate 300. Since the integrated touch display 200 includes a 1/4 wavelength wave plate, light is linearly polarized after passing through the bottom polarizing plate 114. When the linearly polarized light passes through the 1/4 wavelength wave plate 100 with low in-plane phase delay, Elliptical polarized light is generated, so a conventional black and white display screen is solved when the polarized direction of linearly polarized light is perpendicular to the polarized direction of sunglasses (linearly polarized light) worn by the observer. In addition, because this quarter-wavelength plate is made of a material with low in-plane phase delay, it also solves the problem of rainbow stripes in the conventional touch display when the substrate of the touch electrode is plastic.

In some embodiments, the bottom polarizing plate 114 may have a structure (not shown) in which the polarizing sublayer is located between the upper and lower protective sublayers, wherein the material of the polarizing sublayer may be polyvinyl alcohol (PVA), and the protective The material of the sub-layer may be cellulose triacetate (TAC). The display panel 112 may be an electronic paper (Electronic-Paper), a Super Twisted Nematic Liquid-Crystal Display (STN LCD), a thin film type (Thin Film Transistors Liquid-Crystal Display, TFT LCD), polymer Wufa Photodiode (Polymer Light Emitting Diode, PLED), organic light emitting diode (Organic Light Emitting Diode, OLED).

As shown in FIG. 1E, the optical glue 116 is disposed on the quarter-wave plate 100 with a low in-plane retardation. Here, the optical adhesive 116 refers to a special adhesive that can be used for bonding transparent optical elements. In some embodiments, the optical glue 116 may be OCA (Optically Clear Adhesive).

As shown in FIG. 1F, the integrated touch display 200 may further include a protective cover 118, which is adhered to the 1/4 wavelength wave plate 100 with a low in-plane phase delay by the optical adhesive 116. on. This method of bonding by the optical adhesive 116 may also be referred to as a direct bonding method. In other embodiments, the protective cover 118 is not adhered to the quarter-wavelength plate 100 with a low in-plane phase delay through the optical glue 116. Instead, an air layer is formed between the protective cover 118 and the quarter-wave plate 100 with a low in-plane retardation. This method of bonding by air layers can be called air bonding (Air Bonding). Bonding) method (not shown). The material of the protective cover plate 118 can be glass (such as alkali-free glass, soda lime glass, strengthened glass, Gorilla glass, Dragontrail aluminosilicate glass), sapphire, HC protective film, decorative film (Deco Film), functional film (AG , AS, AR, LR, etc.), plastic cover (PC, PMMA, PMMA / PC, PMMA / PC / PMMA, etc.).

FIG. 2 and FIG. 3 respectively show different aspects of the integrated touch displays 400 and 600 according to the embodiment of the present invention.

The embodiment shown in FIG. 2 is different from FIG. 1E in the position of the single-layer touch electrode layer 104. In FIG. 2, the position of the single-layer touch electrode layer 104 is located between the optical adhesive 116 and the quarter-wave plate 100 with a low in-plane retardation. In more detail, the integrated touch display 400 in FIG. 2 is composed of an optical adhesive 116, a composite substrate 500, a display panel 112, and a bottom polarizing plate 114. The composite substrate 500 includes a quarter-wave plate 100 with a low in-plane retardation, a polarizing layer 108, a protective layer 110, and a single-layer contact between the quarter-wave plate 100 with a low in-plane retardation and the optical glue 116.控 electrode layer 104. In the present embodiment, the low in-plane phase retardation of the 1/4 wavelength plate 100 refers to a wave plane retardation R _e is less than 300 nm, for example, in-plane phase retardation R _e is 250,200,150,100 nm . The thickness of the composite substrate 500 provided in this embodiment can be controlled below 170 micrometers (μm).

The embodiment shown in FIG. 3 is different from FIG. 1E in the configuration of the touch electrode layer 102. The integrated touch display 600 in FIG. 3 is composed of an optical adhesive 116, a composite substrate 700, a display panel 112, and a bottom polarizing plate 114. The composite substrate 700 includes a touch electrode layer 102, a quarter-wavelength plate 100 with a low in-plane retardation, a polarizing layer 108, and a protective layer 110. In this embodiment, the touch electrode layer 102 of the composite substrate 700 includes a first touch electrode layer 120 and a second touch electrode layer 122. In this embodiment, the corresponding first touch electrode layer 120 and the second touch electrode layer 122 are respectively located on two sides of the quarter-wavelength plate 100 with a low in-plane phase delay. In more detail, the first touch electrode layer 120 is disposed between the 1/4 wavelength wave plate 100 and the optical glue 116 with a low in-plane phase delay, and the second touch electrode layer 122 is disposed between 1 and the low in-plane phase delay. Between the / 4 wavelength wave plate 100 and the polarizing layer 108. In this embodiment, the corresponding first touch electrode layer 120 and the second touch electrode layer 122 may be a double-layer indium tin oxide (DITO) structure. In some embodiments, the patterns of the first touch electrode layer 120 and the second touch electrode layer 122 are the same, such as a square, a rectangle, a parallelogram, a triangle, or a trapezoid. In other embodiments, the patterns of the first touch electrode layer 120 and the second touch electrode layer 122 are different. In other embodiments, the patterns of the first touch electrode layer 120 and the second touch electrode layer 122 are complementary. In the present embodiment, the low in-plane phase retardation of the 1/4 wavelength plate 100 refers to a wave plane retardation R _e is less than 300 nm, for example, in-plane phase retardation R _e is 250,200,150,100 nm .

The invention provides an integrated touch display, which comprises a composite substrate, a bottom polarizing plate and a display panel, wherein the display panel is located between the composite substrate and the bottom polarizing plate. In more detail, the integrated touch display replaces one of the two polarizing plates traditionally located on both sides of the display panel with a composite substrate. The composite substrate is composed of a quarter-wave plate with a low in-plane retardation, a touch electrode layer, a polarizing layer, and a protective layer. In the embodiment of the present invention, the composite substrate of the integrated touch display has a quarter-wavelength plate. Therefore, when the light passes through the bottom polarizing plate of the integrated touch display, linearly polarized light is generated, and the linearly polarized light passes through the 1/4 wavelength wave plate in the composite substrate to generate elliptically polarized light. Therefore, the integrated touch display provided by the embodiment of the present invention can solve the conventional touch display. When the polarization direction of linearly polarized light is perpendicular to the polarization direction of the sunglasses (with linearly polarized light characteristics) worn by the observer, Black screen issue. In addition, the 1/4 wavelength wave plate is made of a material with a low in-plane phase delay, so it also solves the problem that a rainbow pattern is generated when the substrate of a touch electrode in a conventional touch display is plastic. In addition, the integrated touch display of the embodiment of the present invention has a thinner overall thickness than a conventional touch display.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some modifications and retouching without departing from the spirit and scope of the present invention. this invention The scope of protection shall be determined by the scope of the attached patent application.

Claims (2)

An integrated touch display includes: a composite substrate including: a quarter-wavelength plate with an in-plane phase delay of less than 300 nm; a protective layer; and a polarizing layer disposed on the quarter-wavelength plate And the protective layer; a first touch electrode layer; and a second touch electrode layer disposed between the 1/4 wavelength wave plate and the polarizing layer; a bottom polarizing plate; a display panel located at Between the composite substrate and the bottom polarizing plate; a protective cover; and an optical glue connecting the composite substrate and the protective cover, wherein the first touch electrode layer is disposed between the 1/4 wavelength wave plate and the Between optical glue. The integrated touch display according to claim 1, wherein the thickness of the composite substrate is less than 170 microns.