The present application relates to the technical field of display devices, and in particular to a display panel.
Planar display panels, such as an organic light emitting display (OLED) panel and a display panel using light emitting diode (LED) devices, have been widely used in various consumer electronic products, such as mobile phones, televisions, personal digital assistants, digital cameras, laptop computers, desktop computers, due to their advantages of high image quality, power saving, thin body and wide range of applications, and have become the mainstream of display devices.
At present, the market pursues to develop thin and large-size display panels. However, the overall thickness of the display panel becoming thinner and the size of the display panel increasing will both easily cause the increase of parasitic capacitance between the functional layers, affect the application of functional layers such as touch plate, and also bring negative effects on the display effect of the display panel.
A display panel provided by the embodiments of the present application can, while realizing the thinning of the display panel, increase dielectric spacing between electrode layer in light emitting device layer and touch electrode layer in the display panel, reduce parasitic capacitance of the display panel, and ensure the smooth application of the touch plate in the display panel and a good display effect.
The display panel in the embodiments of the present application includes an array substrate, a light emitting device layer, a touch plate and a color filter film layer. The light emitting device layer is arranged on the array substrate, and the light emitting device layer includes a first electrode layer and an encapsulation layer arranged on a side of the first electrode layer away from the array substrate; the touch plate is positioned on a side of the encapsulation layer away from the array substrate, and the touch plate includes a touch electrode layer; the color filter film layer is arranged between the touch electrode layer and the encapsulation layer to increase a dielectric spacing between the first electrode layer and the touch electrode layer.
In the display panel provided by the embodiment of the present application, by arranging the color filter film layer between the touch electrode layer and the encapsulation layer, the dielectric spacing between the electrode layer in the light emitting device layer and the touch electrode layer is increased. In the case where the size of the display panel is unchanged, the parasitic capacitance between the electrode layer and the touch electrode layer can be reduced. The required capacitance load of an integrated circuit (IC) of the display panel is reduced, thereby ensuring desired display effect of the display panel. In addition, the reduction of the parasitic capacitance between the electrode layer and the touch electrode layer also increases the touch sensitivity of the touch plate in the display panel and improves the touch performance of the touch plate.
For a better understanding of the present application, a detailed description of a display panel according to an embodiment of the present application will be given below with reference to
The inventors have found in intensive studies that, while constantly pursuing a thin body and a large size of a display panel, the overall thickness of the display panel becomes smaller. While the display panel becomes thinner, the dielectric spacing between a touch electrode in a touch panel and an electrode layer below an encapsulation layer of the display panel becomes smaller and the parasitic capacitance between the touch electrode and the electrode layer below the encapsulation layer of the display panel becomes larger. Therefore, when a user touches the display panel, the mutual capacitance value between a sensing electrode and a driving electrode arranged in the touch panel in the display panel decreases, resulting in a problem of poor sensitivity of the touch panel. While pursuing a big size of the display panel, according to C = εr, * S/d (in the formula, C (Capacitance, C) represents the capacitance, εr is the relative dielectric constant, S is the frontal area of the capacitor plate, and d is the distance between the capacitor plates), as the size of the display panel increases, S increases, and the parasitic capacitance C further increases, thus increasing the overall capacitive load of the IC in the display panel, thereby affecting the display effect of the display panel and also affecting the safety and reliability of the display panel during use. Generally, a parasitic capacitance can also be referred to as a stray capacitance. Due to the thin design of a display panel, a capacitance formed between an electrode layer, various circuit modules or electrical elements in the display panel and not in the design of the display panel is connected as a parasitic capacitance. Such parasitic capacitance, due to extreme instability, also affects the mutual capacitance value between the sensing electrode and the driving electrode arranged in the touch plate in the display panel, thereby generating a large interference to the working process of the display panel as a whole, thereby bringing a negative effect on the display effect of the display panel and the touch control performance of the touch plate in the display panel.
Furthermore, a flexible display panel is another hotspot of development in the technical field of display panels. However, a circular polarizer is generally arranged on a side of a light emitting surface of a display panel so as to avoid the reflection phenomenon generated when ambient light is incident on the display panel, thereby ensuring desired display effect. However, the thickness of the circular polarizer is large, and the thickness is generally on the order of several tens of micrometers to several hundreds of micrometers, which hinders the further thinning of the display panel to a certain extent. The circular polarizer has a strong brittleness and cannot be bent repeatedly, which makes it difficult to apply to a flexible and foldable display panel. Therefore, the inventors have made intensive studies to solve the above-mentioned problems of the general display panel, and have provided a novel display panel according to an embodiment of the present application.
Referring to
The display panel of an embodiment of the present application is provided with the color filter film layer 30 between the touch electrode layer 42 and the encapsulation layer 24, so that the dielectric spacing between the first electrode layer 23 in the light emitting device layer 20 and the touch electrode layer 42 is increased. In the case where the size of the display panel 1 is unchanged, the parasitic capacitance between the first electrode layer 23 and the touch electrode layer 42 can be reduced, reducing the required capacitance load of an integrated circuit (IC) in the display panel 1, thereby ensuring desired display effect of the display panel 1. Further, the reduction of the parasitic capacitance between the first electrode layer 23 in the light emitting device layer 20 and the touch electrode layer 42 also increases the touch sensitivity of the touch plate 40 in the display panel 1, improving the touch performance of the touch plate 40. In addition, the color filter film layer 30 can replace the function of a circular polarizer (not shown in the figures) generally provided on the light emitting surface of the display panel, so as to avoid the problem that the display effect is affected by the reflection phenomenon caused by ambient light incident on the display panel, and the thickness of the color filter film layer 30 being lower than the thickness of the circular polarizer can reduce the overall thickness of the display panel 1. Furthermore, the color filter film layer 30 is a flexible and rollable film layer, and replacement of the circular polarizer with the color filter film layer 30 enhances the foldability and bendability of the display panel 1.
Referring to
In some other embodiments, the touch plate includes a base arranged between the touch electrode layer and the color filter film layer. The base includes a buffer inorganic layer and an insulation inorganic layer that are stacked, and the buffer organic layer is arranged close to the color filter film layer.
As shown in
As shown in
In some embodiments, the light emitting layer 22 in the display panel 1 further includes a pixel defining layer having a plurality of pixel openings arranged in an array and a definition object 221 arranged around the pixel openings. Light emitting units are arranged at the pixel openings, and light emitting units 222 of same color are arranged in one-to-one correspondence with light filter units 31 of same color. In some embodiments, the side of the light emitting unit 222 away from the array substrate 10 is at the same level as the side of the definition object 221 away from the array substrate 10 along the thickness direction of the pixel definition layer itself. In these embodiments, since the side of the light emitting unit 222 away from the array substrate 10 is at the same level as the side of the definition object 221 away from the array substrate 10, the flatness of the cathode layer in fabrication of the cathode layer by evaporation in the formation of the display panel can be ensured.
In some embodiments, the color filter film layer 30 includes a plurality of filter units 31 arranged in an array. The light emitting layer 22 includes light emitting units 222 arranged in one-to-one correspondence with the light filter units 31. In some embodiments, the color filter film layer 30 includes a plurality of filter units 31 of different colors arranged alternately.
As shown in
As shown in
In some examples, the light shielding structure 32 in the color filter film layer 30 is a black matrix. In these examples, first, the black matrix can avoid the light emitted from the filter unit 31 from being incident on light emission area of the light emitting display panel 1 corresponding to the adjacent filter unit 31, so as to avoid the phenomenon of color mixing between pixels in the display panel 1 and display color shift, and improve the color rendering accuracy and display precision of the display panel 1. Second, the arrangement of the black matrix can also absorb the ambient light which is incident on the display panel from outside, reduce the probability of reflection of external ambient light in the display panel 1, and improve the user’s viewing experience when using the display panel 1.
In some other examples, the light shielding structure 32 is formed by superimposing the edges of adjacent two of the filter units 31 that are of different colors. In an example, the first color filter unit 31a allows only red light to pass through, and the first color filter unit 31a is arranged corresponding to the first color light emitting unit 222a emitting red light. The second color filter unit 31b allows only green light to pass through, and the second color filter unit 31b is arranged corresponding to the second color light emitting unit 222b emitting green light. The first color filter unit 31a and the second color filter unit 31b are adjacent to each other. The part where the edges of the first color filter unit 31a and the second color filter unit 3 1b are superimposed has the filtering functions of the first color filter unit 31a and the second color filter unit 31b at the same time. That is, since the part where the edges of the first color filter unit 31a and the second color filter unit 31b are superimposed not only can filter out light other than red light but also can filter out light other than green light, the part can have equivalent effect to the shading and light absorption effects of a black matrix. It can not only prevent the phenomenon of mixing of light of different colors between adjacent pixels, but also can absorb ambient light, which avoids the reflection of ambient light in the display panel, and further improves the display effect.
In some optional embodiments, please see
In the above-mentioned embodiments, the color filter film layer 30 may replace the functionality of the circular polarizer, so as to prevent ambient light from reflecting out of the display panel 1 via the reflective material, such as a metal material, arranged in the display panel 1 after ambient light is incident on the interior of the display panel 1. The reason is that, when ambient light incident on the interior of the display panel 1 continues to enter the interior of the display panel 1 through the color filter film layer 30, each filter unit 31 can only allow light of a single color to pass through and filter out and absorb light of other colors, so that most of the light is filtered out by the color filter film layer 30 during ambient light incident on the interior of the display panel 1. When a small portion of the light entering the display panel 1 is reflected inside the display panel 1 and exits the display panel, it will meet the color filter film layer 30 again. When the reflected light is incident on the filter unit 31 of different color, the filter unit 31 of different color will absorb and filter out the reflected light, further reducing the light intensity of the reflected light which can finally exit the display panel 1, and thus the color filter film layer 30 can replace the functionality of the circular polarizer. Therefore, the display panel 1 in the embodiments of the present application does not need to be provided with a circular polarizer to prevent the reflection of ambient light.
Furthermore, the thickness of the circular polarizer is generally on the order of several tens of microns to several hundreds of microns, while the thickness of the color filter film layer 30 in the embodiments of the present application ranges from 0 microns to 10 microns, which does not include the case where the thickness of the color filter film layer 30 is 0 microns. Therefore, the overall thickness of the display panel 1 can be greatly reduced, and the general components for manufacturing the filter unit 31 are organic materials such as a photocurable resin, an alkali soluble resin and a photoinitiator. Thus, the color filter film layer 30 has flexibility and bendability, so as to further ensure the bendability of the display panel 1 and enable the display panel 1 to have bendable and foldable properties. In an embodiment of the present application, the color filter film layer 30 is arranged between the touch electrode layer 42 and the encapsulation layer 24, and the color filter film layer 30 is an insulator, so that the dielectric spacing between the first electrode layer 23 and the touch electrode layer 421 increases, namely, d in C = εr * S/d increases. Therefore, in the case where the size of the display panel 1 is unchanged, namely, the area S is unchanged, the parasitic capacitance between the electrode layer (including the first electrode layer 23 and the second electrode layer 21) in the light emitting device layer 20 and the touch electrode layer 132 decreases, reducing the capacitance load of the display panel IC. While the safe and stable operation of the display panel 1 is ensured, the display effect of the display panel 1 and the touch control performance of the touch plate 40 in the display panel 1 is improved, which brings a good use experience for a user.
In some optional embodiments, when the base of the touch plate includes a buffer inorganic layer and an insulation organic layer, the main reason for the increased dielectric spacing between the first electrode layer 23 and the touch electrode layer 42 is that the color filter film layer 30 is provided in the display panel. In these embodiments, the dielectric spacing between the first electrode layer 23 and the touch electrode layer is increased by dl, 0 µm <dl ≤ 10 µm.
In other optional embodiments, when the base of the touch plate includes the buffer organic layer 411 and the insulation organic layer 412, the total thickness of both the buffer organic layer 411 and the insulation organic layer 412 ranges from 4 µm to 10 µm. Then, the main reason for the increased dielectric spacing between the first electrode layer 23 and the touch electrode layer 42 is that the color filter film layer 30, the buffer organic layer 411 and the insulation organic layer 412 are provided in the display panel. The dielectric spacing between the first electrode layer 23 and the touch electrode layer in the display panel is increased by d2, 4 µm ≤ d2 ≤ 20 µm.
In other examples, the touch plate further includes a first planarization layer on a side of the touch electrode layer away from the array substrate. The above-mentioned light barrier layer is provided on the side of the first planarization layer away from the array substrate. The display panel further includes a second planarization layer arranged on an upper side of the light barrier layer, that is, in this example, the second planarization layer is arranged at the plurality of openings in the light barrier layer and covers a side surface of the light barrier layer away from the array substrate.
In other examples, as shown in
As shown in
As shown in
Along the thickness direction of the display panel 1, the light transmitting portions 422 of the touch electrode layer 42 are in one-to-one correspondence with the openings 51 of the light barrier layer, to form a plurality of light transmission channels. In each sub-pixel of the display panel 1, the light emission channel corresponds to the light transmission channel. It should be noted that a sub-pixel of the display panel 1 refers to the minimum display unit for realizing actual light emitting display on the display surface of the display panel with respect to the overall display panel, and each sub-pixel corresponds to one light emitting unit. In some examples, the sub-pixels include: a red sub-pixel emitting red light, a green sub-pixel emitting green light, and a blue sub-pixel emitting blue light. The light emitted by the light emitting unit 222 needs to pass through the corresponding filter unit 31 and then exits from the filter unit 31, and therefore the light emitting unit 222 and the filter unit 31 of the same color in the display panel correspondingly form a light emission channel of a sub-pixel.
In the display panel 1, thicknesses of the light-emitting device layer 20, the color filter film layer 30, the touch plate 40 and the barrier 50, and an arrangement of the light emission channels and the light transmission channels satisfy the following relationship:
in the sub-pixel, for light emitted via a first one of the light emission channels, a part of the light is emitted outside through the first one of the light transmission channels of the sub-pixel, and the other part of the light enters a second one of the light transmission channels of an adjacent sub-pixel and is totally absorbed by the barrier surrounding the second one of the light transmission channels.
It needs to be stated that a plurality of sub-pixels are arranged in a pre-set manner in a display panel. For clarity of description herein, a first sub-pixel is used to represent a certain sub-pixel of a plurality of sub-pixels in a display panel, and the first sub-pixel having a first light emission channel. With reference to the first sub-pixel, sub-pixels adjacent to the first sub-pixel are all referred to as second sub-pixels, and the second sub-pixel has a second light transmission channel. That is, in an embodiment of the present application, the first sub-pixel and the second sub-pixel are used to distinguish a certain sub-pixel and an adjacent sub-pixel in a display panel.
In some examples, as shown in
With particular reference to
In these embodiments, in the display panel, thicknesses of the light-emitting device layer 20, the color filter film layer 30, the touch plate 40 and the barrier 50, and an arrangement of the light emission channels and the light transmission channels satisfy the following relationship:
in the sub-pixel, for light emitted via a first light emission channel, a part of the light is emitted outside through the first light transmission channel of the sub-pixel, and the other part of the light enters a second light transmission channel of an adjacent sub-pixel and is totally absorbed by the barrier surrounding the second light transmission channel.
As shown in
Number | Date | Country | Kind |
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202011239917.9 | Nov 2020 | CN | national |
This application is a continuation of International Application No. PCT/CN2021/115164, filed on Aug. 27, 2021, which claims priority to Chinese Patent Application No. 202011239917.9, filed on Nov. 09, 2020, both of which are hereby incorporated by reference in their entireties.
Number | Date | Country | |
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Parent | PCT/CN2021/115164 | Aug 2021 | WO |
Child | 18169413 | US |