Display substrate, display panel and display device

The present disclosure provides a display substrate, a display panel and a display device, and belongs to the field of display technology. The display substrate includes a plurality of display islands and a plurality of connection parts; any two adjacent display islands are connected through one of the plurality of connection parts; the plurality of connection parts define a plurality of openings of a base substrate of the display substrate; at least part of the plurality of openings is provided therein with a torsional structure, the torsional structure is connected between two connection parts of connection parts defining the opening in which the torsional structure is located, the two connection parts extending in substantially a same direction; and the torsional structure is stretchable in a direction in which it is connected with the two connection parts.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Chinese Patent Application No. 201910600466.8, filed on Jul. 4, 2019, the entire contents of which are hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to the field of display technology, and particularly, to a display substrate, a display panel, and a display device.

BACKGROUND

Flexible display devices are considered to be the mainstream of next-generation displays and have attracted extensive attention due to their advantages such as bendability, good impact resistance, strong shock resistance, light weight, small size and easy portability. With the development of flexible display technology, display panels tend to be stretchable.

However, in an existing stretchable display substrate, when the stretching force is large, the normal display of the stretched display panel may be affected, affecting the display effect.

SUMMARY

In an aspect, embodiments of the present disclosure provide a display substrate, including: a plurality of display islands and a plurality of connection parts; any two adjacent display islands are connected through one of the plurality of connection parts; the plurality of connection parts define a plurality of openings of a base substrate of the display substrate; at least part of the plurality of openings is provided therein with a torsional structure, the torsional structure is connected between two connection parts of connection parts defining the opening in which the torsional structure is located, the two connection parts extending in substantially a same direction; and the torsional structure is stretchable in a direction in which it is connected with the two connection parts.

In some embodiments, for every four display islands adjacent in a first direction and a second direction perpendicular to the first direction, four connection parts connect the four display islands and define one of the plurality of openings of the base substrate.

In some embodiments, the torsional structure is connected between two connection parts of the four connection parts defining the opening in which the torsional structure is located, the two connection parts extending in substantially a same direction and having a shorter distance therebetween than a distance between the other two connection parts of the four connection parts.

In some embodiments, a width-to-height ratio of the torsional structure ranges from 1:5 to 1:1.5.

In some embodiments, the torsional structure has a shape of a symmetrical figure.

In some embodiments, the symmetrical figure is arc-shaped; and the width-to-height ratio of the symmetrical figure ranges from 1:3 to 1:1.5.

In some embodiments, the symmetrical figure is an ellipse ring or an S shape; and a width-to-height ratio of the symmetrical figure ranges from 1:5 to 1:3.

In some embodiments, the torsional structure is connected between intermediate positions of the two connection parts extending in substantially a same direction among the connection parts defining the opening in which the torsional structure is located.

In some embodiments, the torsional structure and the connection parts connected thereto are formed as a single piece.

In some embodiments, the display substrate includes a flexible substrate; and the torsional structure and the flexible substrate are formed as a single piece.

In some embodiments, the plurality of display islands are arranged in an array.

In some embodiments, the opening is I-shaped; the torsional structure is connected between two connection parts that define a vertical portion of the I-shaped opening.

In some embodiments, the torsional structure is connected between intermediate positions of the two connection parts that define the vertical portion of the I-shaped opening.

In some embodiments, the torsional structure is formed in each of the plurality of openings.

In some embodiments, the torsional structure is formed in only a part of the plurality of openings, and in a same direction, torsional structures are provided at an interval not exceeding four openings.

In another aspect, an embodiment of the present disclosure provides a display panel, including any one of the above display substrates.

In still another aspect, an embodiment of the present disclosure provides a display device, including any one of the above display panels.

DETAILED DESCRIPTION

In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, the present disclosure will be described in further detail below with reference to the accompanying drawings and specific implementations.

As shown inFIG. 3, in an existing stretchable display substrate, a base substrate is a patterned flexible substrate, the patterned substrate includes a plurality of display islands and a plurality of connection bridges, and two adjacent display islands are connected by a connection bridge, and thus stretchability is achieved by the deformation of the display islands and the openings between the connection bridges.

The inventor found that in the existing stretchable display substrate, when the stretching force is large, some display islands may be twisted to some extent due to the stretching (part of the edge areas of the display islands protrudes from the original overall plane of the stretchable display substrate), that is, Z-axis deformation occurs. As the stretching force increases, the Z-axis deformation becomes more obvious, which affects the normal display of the stretchable display panel.

Embodiments of the present disclosure provide a display substrate, which is particularly suitable for a stretchable display substrate. As shown inFIGS. 1 and 2, the display substrate includes: a plurality of display islands1and a plurality of connection parts2; any two adjacent display islands1are connected through the connection part2. The plurality of connection parts2define a plurality of openings of the base substrate of the display substrate, and at least part of the plurality of openings is provided with a torsional structure3. The torsional structure3is connected between two connection parts extending in substantially a same direction among connection parts that define the opening where the torsional structure is located, and the torsional structure is stretchable in a direction in which it is connected with the two connection parts.

In an embodiment, the torsional structure3is connected between the two connection parts that extend in substantially a same direction and have a relatively smaller distance therebetween among the connection parts that define the opening where the torsional structure is located. For example, for any four display islands1adjacent in a first direction and adjacent in a second direction among the plurality of display islands, four connection parts2connect the four display islands and define one of the opening of the base substrate. At least part of the plurality of openings of the base substrate is provided with a torsional structure3, the torsional structure3is connected with two connection parts2extending in a same direction and having a smaller distance therebetween among the four connection parts2, and the torsional structure3is stretchable in its connection direction with the two connection parts2.

The display substrate provided in the embodiment may include: a base substrate, and devices on the base substrate such as display units, signal lines, etc. The base substrate is a patterned substrate, and has a plurality of display islands1and a plurality of connection parts2, and the plurality of connection parts2define a plurality of openings. Therefore, it can also be considered as that a plurality of openings divide the base substrate into a plurality of display islands1and a plurality of connection parts2. One or more display units are provided in the display island1, and each display unit may include devices such as an OLED device, a driving transistor, and the like. Signal lines are provided in the connection parts2to connect the display units in respective display islands1, so as to supply control signals to the display units through the signal lines to control the operation of the display substrate.

When the display substrate is stretched, deformation of each opening (opening defined by the connection parts2) on the base substrate is adapted to the stretching of the display substrate. When the stretching force received by the display substrate is large, Z-axis deformation occurs to the display island1as the deformation of the opening of the base substrate increases. As the stretching force increases, the Z-axis deformation becomes more obvious, which affects the normal display of the stretchable display panel.

It should be noted that the deformation direction of the opening is related to the direction of the stretching force, and the opening is defined by the connecting parts2. In the embodiments of the present disclosure, the torsional structure3is provided between two connection parts2, and the torsional structure3is stretchable in the connection direction, so that stretching of the base substrate can be realized, and when the stretching force is large, excessive stretching of the display substrate can be restricted to a certain extent, degree of the Z-axis deformation of the display island1can be suppressed, and thus problems of display defects of the stretchable display substrate caused by the large stretching force can be avoided as much as possible.

In some embodiments, the plurality of display islands1may be arranged according to a certain rule, and two adjacent display islands1are connected by a connection part2. For example, as shown inFIG. 1, the plurality of display islands1are arranged in an array, and each display island1is connected to another display island1adjacent thereto in a row direction or a column direction through the connection part2. In this case, the first direction may be the row direction of the array, and the second direction may be the column direction of the array.

As shown inFIGS. 1 and 2, any two display islands1adjacent in the row direction are connected by one connection part2; any two display islands1adjacent in the column direction are connected by one connection part2. That is to say, any four display islands1in two adjacent rows and two adjacent columns are connected by four connection parts2. In the embodiment, the four connection parts2define an opening of the base substrate.

It could be understood that the plurality of display islands1in the embodiment may also be arranged in other manners, such as in an annular arrangement (e.g., a plurality of annular display islands each including a plurality of display islands1), and the like. The shape of the opening defined by the four connection parts2may be determined according to the connection position of each connection part2with respective display islands1. Specifically, the opening may be I-shaped, T-shaped or have other shapes, which will not be described in detail herein.

In order to explain the display substrate of the present embodiments more clearly, a case in which the plurality of display islands1are arranged in an array, and the opening defined by the four connection parts2is I-shaped is taken as an example for description.

As shown inFIG. 2, when the opening defined by the four connection parts2is I-shaped, the connection parts2and the display islands1may be connected as follows: each display island1other than the display island1on the edge is connected with four display islands1adjacent thereto in the row direction or in the column direction respectively through four connection parts2, the connection position of each of the four connection parts2with the display island1is on a side of the display island1away from its adjacent display island1connected through the connection part2, and the four connection parts2connected to a same display island1are independent of each other and do not overlap. Therefore, the two display islands1adjacent in the row direction is connected to the connection part2in a symmetric manner, and two display islands1adjacent in the column direction is connected to the connection part2in a symmetric manner. As shown inFIG. 2, in the four display islands1in two adjacent rows and two adjacent columns, two connection parts2each connecting two display islands1adjacent in the row direction and two connection parts2each connecting two display islands1adjacent in the column direction define an I-shaped opening. Specifically, two display islands1in the first row are connected by a connection part2extending in the row direction, two display islands1located in the second row are connected by a connection part2extending in the row direction (not shown inFIG. 2, and referring toFIG. 1), two display islands located in the first column are connected by a connection part2extending in the column direction, and two display islands located in the second column are connected by a connection part2extending in the column direction, and the four connection parts2define an I-shaped opening. The I-shaped opening may be provided therein with a torsional structure3, and the torsional structure is connected between two connection parts2extending in a same direction and having a smaller distance therebetween among the four connection parts, that is, between two connection parts2each connecting two display islands1located in a same column (i.e., two connection parts2extending in the column direction), and the torsional structure3is stretchable in the connection direction with the connection parts2.

It could be understood that, in order to clearly show the arrangement of the openings and the torsional structures3in the openings,FIGS. 1 and 2only schematically show general areas in which the connection parts2and the display islands1are respectively located, but do not show signal lines that actually connect two adjacent display islands1in the connection part2or the specific connection between the signal lines and the display islands1. It should be noted that although the areas where the four connection parts2are located are not clearly shown as being separated from each other inFIGS. 1 and 2, in practical implementation, the four connection parts2connecting the four display islands1in adjacent rows and adjacent columns may be separated from each other. Needless to say, it can be understood that the solution of dividing a base substrate into a plurality of display islands1and a plurality of connection parts2by a plurality of I-shaped openings on the flexible substrate may also refer to other technical solutions in the related art, which will not be repeated in detail herein.

In the embodiments, when the opening defined by the four connection parts2is I-shaped, the torsional structure3is connected to the two connection parts2that define the middle part of the I-shaped opening. That is, as shown inFIGS. 1 and 2, the torsional structure3connects the two connection parts2that define the “1” portion (i.e., the vertical portion of the I-shaped opening, which extends in a second direction and has a larger length than a portion of the I-shaped opening extending in a first direction perpendicular to the second direction) of the I-shaped opening. In a case where the opening defined by the four connection parts2is I-shaped, when the display substrate is stretched, the two connection parts2that define the “I” portion of the I-shaped opening are more likely to deform than the other two connection parts2, That is, the “I” portion of the I-shaped opening is easier to deform under the same stretching force. By connecting the two connection parts2that define the middle part of the I-shaped opening through the torsional structure3, the torsional structure3can effectively suppress excessive deformation of the I-shaped opening, thereby avoiding the problem of display defects caused by the excessive deformation. Because deformation of the other two connection parts2defining the “-” portions in the I-shaped opening (i.e., horizontal portions of the I-shaped opening, each of which extends in the first direction and has a smaller length than the portion of the I-shaped opening extending in the second direction) is not large during stretching, the torsional structure3may not be provided between the two connection parts2.

In some embodiments, in order to further improve the stretchability of the display substrate and achieve good stretchability of the display substrate in both row and column directions, a plurality of I-shaped openings whose “1” portions (i.e., vertical portion) extend respectively along the row direction (e.g., horizontal direction) or column direction (e.g., vertical direction) may be formed. As shown inFIGS. 1 and 2, a plurality of I-shaped openings whose “1” portions extend along the row direction and a plurality of I-shaped openings whose “1” portions extend along the column direction are alternately arranged in both the row direction and the column direction. In this way, when stretching the display substrate, good stretchability can be achieved in both row and column directions. The I-shaped openings whose “1” portions (i.e., vertical portion) extend along different directions may have a same structure, which is not repeatedly described herein.

In the embodiments of the present disclosure, the shape of the torsional structure3may be a curve. In some embodiments, the torsional structure3is in the shape of a symmetrical figure such as an arc, an ellipse (as shown inFIG. 4), an S-shape (as shown inFIG. 5), etc., which is not particularly limited in the present disclosure, as long as the torsional structure3is stretchable in the connection direction with the connection parts2. It could be understood that the torsional structure3has a certain stretchability, and it is subjected to a stretching force during the stretching of the display substrate, and by designing its shape as a symmetrical figure, the torsional structure3can better adapt to the stretching force, so as to avoid the occurrence of undesirable phenomena such as breakage caused by excessive stretching force.

In some embodiments, the width-to-height ratio of the torsional structure3is in the range of 1:5 to 1:1.5. It should be noted that in the embodiments, the width of the torsional structure3refers to its maximum width, and the height thereof refers to the length of the area occupied by the torsional structure3. For any torsional structure3, its width and height can be measured by the following method: placing the torsional structure3in the smallest rectangle that can accommodate the torsional structure3, and taking the width and length of the rectangle as the width and height of the torsional structure3. For example, the width of the torsional structure3shown inFIG. 2is the length of the torsional structure3in the row direction, and the height thereof is the length of the torsional structure3in the column direction.

In some embodiments, the torsional structure3is in the shape of an arc. In this case, the width-to-height ratio of the torsional structure3may be in the range of 1:3 to 1:1.5. It has been proved by relevant experiments that the torsional structure3having the width-to-height ratio in the range of 1:3 to 1:1.5 has less influence on the stretchability of the display substrate and more obvious suppressing effect on Z-axis deformation of the display substrate, and can thus significantly improve the display effect of the display panel.

It should be noted that the arc in the present disclosure refers to a single arc including only one curved portion.

In some embodiments, as shown inFIGS. 4 and 5, the torsional structure3in the embodiments may be in the shape of an ellipse ring or an S shape. In this case, the width-to-height ratio of the ellipse ring or the S-shape may be in the range of 1:5 to 1:3.

It should be noted here that the torsional structure3in the shape of an ellipse ring may also be regarded as one pair of arc-shaped torsional structures3that are symmetric (axisymmetric), and the torsional structure3in the S shape may also be regarded as one pair of arc-shaped torsional structure3that are symmetric (centrosymmetric). It has been proved by relevant experiments that when the torsional structure3is in the shape of an ellipse ring or an S-shape, and its width-to-height ratio is in the range of 1:5 to 1:3, the torsional structure3has less effect on the stretchability of the display substrate, and strengthened suppressing effect on the Z-axis deformation, which can significantly improve the display effect of the display panel.

In some embodiments, the torsional structure3is connected between the intermediate positions of the two connection parts2. When stretching the display substrate, the intermediate region of the opening formed by the connection parts2has the largest deformation, and the torsional structure3is connected with the middle of each of the two connection parts2that define the opening, that is, the torsional structure3is approximately located in the middle region of the opening, so that the suppressing effect on the Z-axis deformation of the display substrate is more obvious. For example, as shown inFIGS. 1 and 2, the torsional structure3is connected with the middle of each of the connection parts2that defines the vertical portion of the I-shaped opening.

In the display substrate of the embodiments, the torsional structure3may be formed in each opening; alternatively, the torsional structure3may be provided in only part of the openings, so as not to increase the complexity of the manufacturing process of the display substrate. For example, in a same direction (in the row direction or column direction), the torsional structures3are provided at an interval not exceeding four openings.

The torsional structure3may be formed with the connection parts2connected thereto as a single piece, in other words, the torsional structure3may have the same structure as the connection parts2. With this configuration, the manufacturing process of the display substrate can be simplified as much as possible, and the connection of the torsional structure3with the connection parts2is good.

In an embodiment, as shown inFIG. 6, the connection part2may include a glass substrate (which will be removed later)11, a flexible substrate12, a barrier layer13, a buffer layer14, a first conductive layer (in a same layer as the source and drain electrodes of the thin film transistor)15, a planarization layer16, a second conductive layer17, and other layers. The material of the flexible substrate12may include polyimide, and the thickness of the flexible substrate12may range from 5 μm to 15 μm. The barrier layer13and the buffer layer14each may be stacked film layers made of SiNx and/or SiO2, with a total thickness ranging from 1500 Å to 8500 Å. The material of the first conductive layer15may be Ti/Al/Ti alloy, and the thickness thereof may range from 4000 Å to 9000 Å. The planarization layer16may be made of a resin material and have a thickness in the range of 1 μm to 2 μm. The second conductive layer17may have a thickness in the range of 500 Å to 2500 Å.

In an embodiment, as shown inFIG. 7, the torsional structure may be formed with only the flexible substrate12as a single piece, that is, the torsional structure only includes the flexible substrate12, so as to be connected with the connection parts through the flexible substrate. Needless to say, the torsional structure may also be formed with the flexible substrate and partial layer(s) in the connection part2as a single piece, which is not limited in the embodiment.

In another aspect, an embodiment of the present disclosure further provides a display panel, including any one of the display substrates provided in the above embodiments.

The display panel provided in the embodiment may be a stretchable display panel, which can be used in any product or component with a display function such as an electronic paper, a mobile phone, a tablet computer, a TV, a monitor, a notebook computer, a digital photo frame, a navigator, etc. Since the display panel in the embodiment includes the display substrate of the present disclosure, the display panel can still achieve good display effect in a stretched state.

In still another aspect, an embodiment of the present disclosure further provides a display device, including the display panel of the present disclosure.

The display device provided in the embodiment may be any product or component with a display function such as an electronic paper, a mobile phone, a tablet computer, a TV, a monitor, a notebook computer, a digital photo frame, a navigator, etc. Since the display device in the embodiment includes the display panel of the present disclosure, the display device can still achieve good display effect in a stretched state.

It could be understood that the above implementations are merely exemplary implementations employed to explain the principle of the present disclosure, but the present disclosure is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and scope of the present disclosure, and such modifications and improvements are also considered to be within the protection scope of the present disclosure.