Array substrate and preparation method thereof, display panel and driving method thereof

The present disclosure provides an array substrate and a preparation method thereof, a display panel and a driving method thereof, which belongs to the field of display technology. The array substrate includes a base substrate, a driving circuit layer, a reflective electrode layer, a light-emitting layer, an electrochromic layer, and a common electrode layer. The driving circuit layer is provided with a first and second driving circuit. The reflective electrode layer is provided on a side of the driving circuit layer away from the base substrate and provided with a first and second reflective electrode insulated from each other. The light-emitting layer includes a light-emitting unit arranged on the surface of the second reflective electrode away from the base substrate. The electrochromic layer is arranged on the surface of the first reflective electrode away from the base substrate. The common electrode layer covers the electrochromic layer and the light-emitting unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of and priority to Chinese Patent Application No. 202010128262.1 filed on Feb. 28, 2020, the contents of which being incorporated by reference in their entirety herein.

TECHNICAL FIELD

The present disclosure relates to the field of display technology and, in particular to an array substrate and a preparation method thereof, as well as a display panel and a driving method thereof.

BACKGROUND

The mirror display panel has both a mirror function and a display function, and has a huge application prospect in the field of smart home and commercial display. Current mirror display panels include a mirror reflection layer to function as a mirror, but the high reflectivity (about 50%) of the mirror reflection layer reduces the overall transmittance and contrast. It is necessary to increase the light source intensity of the display module to achieve display visualization.

The above-mentioned information disclosed in the background section is only used to enhance the understanding of the background of the present disclosure, so it may include information that does not constitute the prior art known to those of ordinary skill in the art.

SUMMARY

The purpose of the present disclosure aims to provide an array substrate and a preparation method thereof, as well as a display panel and a driving method thereof, which can turn on or turn off the mirror display function and improve the contrast of the display image.

In order to achieve the above-mentioned purpose of the disclosure, the present disclosure adopts following technical solutions.

According to a first aspect of the present disclosure, there is provided an array substrate, including:

a base substrate;

a driving circuit layer provided on a side of the base substrate, wherein the driving circuit layer is provided with a first driving circuit and a second driving circuit;

a reflective electrode layer provided on a side of the driving circuit layer away from the base substrate, wherein the reflective electrode layer is provided with a first reflective electrode and a second reflective electrode, the first reflective electrode is electrically connected to an output terminal of the first driving circuit and insulated from the second reflective electrode, and the second reflective electrode is electrically connected to an output terminal of the second driving circuit;

a light-emitting layer including a light-emitting unit disposed on a surface of the second reflective electrode away from the base substrate;

an electrochromic layer provided on a surface of the first reflective electrode away from the base substrate; and

a common electrode layer covering a surface of the electrochromic layer away from the base substrate and a surface of the light-emitting unit away from the base substrate.

In an exemplary embodiment of the present disclosure, an amount of the second reflective electrode is multiple, and the first reflective electrode is formed with a plurality of hollowed-out first pixel windows in one-to-one correspondence with each of the second reflective electrodes, and any one of the second reflective electrodes is arranged in the corresponding first pixel window.

In an exemplary embodiment of the present disclosure, the first reflective electrode is an integrated structure.

In an exemplary embodiment of the present disclosure, a material of the electrochromic layer is a combination of one or more of tungsten oxide, molybdenum oxide, titanium oxide, vanadium oxide and niobium oxide, or a material of the electrochromic layer is a combination of one or more of nickel oxide, iridium oxide, cobalt oxide and rhodium oxide.

In an exemplary embodiment of the present disclosure, the array substrate further includes:

a pixel defining layer provided on a side of the driving circuit layer away from the base substrate, wherein the pixel defining layer is formed with a hollowed-out second pixel window, the second reflective electrode is arranged in the second pixel window, and the first reflective electrode covers a side of the pixel defining layer away from the base substrate.

In an exemplary embodiment of the present disclosure, the light-emitting unit is a light-emitting diode, and the array substrate further includes:

a passivation protection layer provided between the reflective electrode layer and the common electrode layer, wherein the passivation protection layer is formed with a hollowed-out third pixel window, and the light-emitting unit is embedded in the third pixel window.

According to a second aspect of the present disclosure, there is provided a method for preparing an array substrate, including:

providing a base substrate;

forming a driving circuit layer on a side of the base substrate, wherein the driving circuit layer is provided with a first driving circuit and a second driving circuit;

forming a reflective electrode layer on a side of the driving circuit layer away from the base substrate, wherein the reflective electrode layer is provided with a first reflective electrode and a second reflective electrode, the first reflective electrode is electrically connected to an output terminal of the first driving circuit and insulated from the second reflective electrode, and the second reflective electrode is electrically connected to an output terminal of the second driving circuit;

forming a light-emitting layer, wherein the light-emitting layer includes a light-emitting unit disposed on a surface of the second reflective electrode away from the base substrate;

forming an electrochromic layer, wherein the electrochromic layer covers a surface of the first reflective electrode away from the base substrate; and

forming a common electrode layer, wherein the common electrode layer covers a surface of the electrochromic layer away from the base substrate and a surface of the light-emitting unit away from the base substrate.

According to a third aspect of the present disclosure, there is provided a display panel, including the array substrate descried above.

According to a fourth aspect of the present disclosure, there is provided a driving method of a display panel for driving the display panel described above, wherein the driving method of the display panel includes:

under a first situation, applying a first control signal to the first driving circuit, so that the first driving circuit applies a first control voltage to the first reflective electrode according to the first control signal; applying a first common voltage to the common electrode layer, so that a potential difference between the first reflective electrode and the common electrode layer is within a first preset range, so that the electrochromic layer is in a transparent state; and

under a second situation, applying a second control signal to the first driving circuit, so that the first driving circuit applies a second control voltage to the first reflective electrode according to the second control signal; applying a second common voltage to the common electrode layer, so that a potential difference between the first reflective electrode and the common electrode layer is within a second preset range, so that the electrochromic layer is in an opaque state.

In the array substrate and the preparation method thereof, the display panel and the driving method thereof provided in the present disclosure, the light-emitting layer is arranged on a side of the reflective electrode layer away from the base substrate, so that the light emitted by the light-emitting unit can be emitted without passing through the reflective electrode layer, and the overall light transmittance is improved and the loss of emitted light is reduced. Not only that, the second reflective electrode can also reflect the light irradiated by the light-emitting unit toward the base substrate, thereby further increasing the proportion of emitted light. Therefore, the array substrate has higher light transmittance and higher light emitting rate, thereby improving the contrast of the display image, and reducing the luminous intensity of the light-emitting unit to reduce the power consumption of the array substrate. The array substrate is provided with an electrochromic layer between the first reflective electrode and the common electrode layer. The electrochromic layer can change its light transmission state in response to changes in the electromotive force between the first reflective electrode and the common electrode layer, for example, reversible conversion between the transparent state and the opaque state may be achieved. Therefore, the array substrate can independently control on and off of the mirror display function as needed, to adapt to different application scenarios and achieve better display effects.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms, and should not be construed as being limited to the examples set forth herein; on the contrary, the provision of these embodiments makes the present disclosure more comprehensive and complete, and fully conveys the concept of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to give a sufficient understanding of the embodiments of the present disclosure.

In the figure, the thickness of regions and layers may be exaggerated for clarity. The same reference numerals in the figures indicate the same or similar structures, and thus their detailed descriptions will be omitted.

The described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to give a sufficient understanding of the embodiments of the present disclosure. However, those skilled in the art will realize that the technical solutions of the present disclosure can be practiced without one or more of the specific details, or other methods, components, materials, etc. can be used. In other cases, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring the main technical ideas of the present disclosure.

When a certain structure is “on” other structures, it may mean that the certain structure is integrally formed on other structures, or that the certain structure is “directly” arranged on other structures, or that the certain structure is “indirectly” arranged on other structures through another structure.

The terms “a”, “an”, and “the” are used to indicate the presence of one or more elements, components, etc. The terms “including” and “having” are used to indicate open-ended inclusion and mean that there may be additional elements, components, etc. in addition to the listed elements, components, etc. The terms “first” and “second” are only used as marks, and are not limited to the number of objects.

FIG.1is a schematic diagram of the structure of a mirror display panel in the related art. Referring toFIG.1, in the related art, a mirror display panel includes a base substrate910, a light-emitting layer920, and a mirror reflection layer930that are sequentially stacked. The mirror reflection layer930adopts a high reflection film having light transmittance, and the reflectivity is generally around 50%. For example, the mirror reflection layer930may adopt a semi-transparent and semi-reflective film. In this way, the mirror reflection layer930of the mirror display panel can reflect ambient light (indicated by dotted lines inFIG.1) to achieve a mirror display effect. The light-emitting layer920generally includes a plurality of light-emitting units921, and the light emitted by the light-emitting units921passes through the mirror reflection layer930to achieve the image display. However, the light emitted by the light-emitting unit921will be partially reflected by the mirror reflection layer930, resulting in high reflection loss, which causes a decrease in the overall light transmittance and reduces the light emitting rate and contrast of the mirror display panel. Not only that, the mirror display panel needs to increase the light-emitting brightness of the light-emitting unit921, which may result in an increase in power consumption.

The present disclosure provides an array substrate, as shown inFIGS.2to4. The array substrate includes a base substrate100, a driving circuit layer200, a reflective electrode layer300, a light-emitting layer, an electrochromic layer500, and a common electrode layer600.

In the embodiment, the driving circuit layer200is provided on a side of the base substrate100. The driving circuit layer200is provided with a first driving circuit201and a second driving circuit202. The reflective electrode layer300is provided on a side of the driving circuit layer200away from the base substrate100. The reflective electrode layer300is provided with a first reflective electrode301and a second reflective electrode302. The first reflective electrode301is electrically connected to an output terminal of the first driving circuit201and insulated from the second reflective electrode302. The second reflective electrode302is electrically connected to an output terminal of the second driving circuit202. The light-emitting layer includes a light-emitting unit410disposed on a surface of the second reflective electrode302away from the base substrate100. The electrochromic layer500is provided on a surface of the first reflective electrode301away from the base substrate101. The common electrode layer600covers a surface of the electrochromic layer500away from the base substrate100and a surface of the light-emitting unit410away from the base substrate100.

The array substrate provided in the present disclosure is provided with a reflective electrode layer300, which can reflect ambient light to achieve a mirror reflection function. In the array substrate, the light-emitting layer is arranged on a side of the reflective electrode layer300away from the base substrate100, so that the light emitted by the light-emitting unit410can emit out without passing through the reflective electrode layer300. The overall light transmittance is improved, and the loss of emitted light is reduced. Not only that, the second reflective electrode302can also reflect the light irradiated by the light-emitting unit410toward the base substrate100, thereby further increasing the proportion of emitted light. Therefore, the array substrate of the present disclosure does not only avoid the loss of emitted light caused by the reflective electrode layer300, but also increase the proportion of emitted light by means of the reflection function of the second reflective electrode302. The array substrate has higher light transmittance and higher light emitting rate, thereby improving the contrast of the display image, and reducing the luminous intensity of the light-emitting unit410to reduce the power consumption of the array substrate.

The array substrate is provided with an electrochromic layer500between the first reflective electrode301and the common electrode layer600. The electrochromic layer500can change its light transmission state in response to changes in the electromotive force between the first reflective electrode301and the common electrode layer600, for example, reversible conversion between the transparent state and the opaque state may be achieved. When the array substrate does not need to perform as a mirror display, a voltage on the first reflective electrode301can be controlled by the first driving circuit201to make the electrochromic layer500in an opaque state, which prevents ambient light from irradiating the first reflective electrode301, suppresses or eliminates the mirror display of the array substrate, avoids the influence of ambient light on the display image, and improves the contrast of the display image. Not only that, since there is no interference from ambient light, the array substrate does not need to increase the brightness of the light-emitting unit, in turn, the power consumption of the array substrate is reduced. When the array substrate needs to perform mirror display, the voltage on the first reflective electrode301can be controlled by the first driving circuit201to make the electrochromic layer500in a transparent state, so that ambient light can be irradiated to the first reflective electrode301and then be reflected, so that the array substrate realizes the mirror display. Therefore, the array substrate can independently control the on and off of the mirror display function according to requirements to adapt to different application scenarios and achieve better display effects.

Hereinafter, in conjunction with specific drawings, the structure, principles, and effect of the array substrate of the present disclosure will be further explained and described.

The base substrate100may be a base substrate100of an inorganic material or a base substrate100of an organic material. For example, in an embodiment of the present disclosure, the material of the base substrate100may be soda-lime glass, quartz glass, sapphire glass, or other glass materials, or may be stainless steel, aluminum, nickel, or other metallic materials. In another embodiment of the present disclosure, the material of the base substrate100may be polymethyl methacrylate (PMMA), polyvinyl alcohol (PVA), or polyvinyl phenol (PVP), polyether sulfone (PES), polyimide, polyamide, polyacetal, poly carbonate (PC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN) or a combination thereof. In another embodiment of the present disclosure, the base substrate100may also be a flexible base substrate100. For example, the material of the base substrate100may be polyimide (PI). The base substrate100may also be a composite of multiple layers of materials. For example, in an embodiment of the present disclosure, the base substrate100may include a bottom film layer, a pressure-sensitive adhesive layer, a first polyimide layer and the second polyimide layer that are sequentially stacked.

The driving circuit layer200is disposed on one side of the base substrate100, and it may adopt an active driving structure or a passive driving structure, or a combination of an active driving structure and a passive driving structure. As shown inFIGS.2and3, the driving circuit layer200may be provided with a first driving circuit201, and the first driving circuit201is used to control the voltage on the first reflective electrode301.

In an embodiment of the present disclosure, the first driving circuit201may be a connecting lead. One end of the connecting lead may be connected to the first reflective electrode301, and the other end of the connecting lead may be connected to a driving pad. The driving pad is used to be electrically connected to the driver. In this way, the driver can apply the required voltage to the driving pad, and apply the required voltage to the first reflective electrode301through the driving pad and the connecting lead, which can realize the passive driving of the first reflective electrode301.

For example, the driver can apply the first control signal to the connecting lead through the driving pad, and the voltage of the first control signal is the first control voltage. In this way, the connecting lead can apply the first control voltage to the first reflective electrode301. In other words, the driver may apply the first control signal to the first driving circuit201, so that the first driving circuit201applies the first control voltage to the first reflective electrode301according to the first control signal. The driver can also apply a first common voltage to the common electrode layer600, so that the potential difference between the first reflective electrode301and the common electrode layer600is within a first preset range, thereby making the electrochromic layer500in a transparent state. At this time, the display effect of the array substrate is shown inFIG.5. Referring toFIG.5, in the surrounding area of each light-emitting unit410, the electrochromic layer500is in a transparent state, so that the array substrate can reflect the ambient light.

For another example, the driver can apply the second control signal to the connecting lead through the driving pad, and the voltage of the second control signal is the second control voltage. In this way, the connecting lead can apply the second control voltage to the first reflective electrode301. In other words, the driver may apply the first control signal to the first driving circuit201, so that the first driving circuit201applies the first control voltage to the first reflective electrode301according to the first control signal. The driver may also apply a second common voltage to the common electrode layer600, so that the potential difference between the first reflective electrode301and the common electrode layer600is within a second preset range, thereby making the electrochromic layer500in an opaque state. At this time, the display effect of the array substrate is shown inFIG.6. Referring toFIG.6, in the surrounding area of each light-emitting unit410, the electrochromic layer500is in an opaque state, so that the array substrate cannot reflect the ambient light.

In another embodiment of the present disclosure, the first driving circuit201may be a circuit composed of electronic components. For example, the first driving circuit201may include a lead wire and a thin film transistor connected to the lead wire, so as to control the voltage on the first reflective electrode301through active driving. It is understandable that a storage capacitor may also be provided on the first driving circuit201.

For example, as shown inFIG.7, the first driving circuit201may include a first thin film transistor TFT1and a second thin film transistor TFT2. In the embodiment, one of the first thin film transistor TFT1and the second thin film transistor TFT2is an N-type thin film transistor, and the other is a P-type thin film transistor. The first thin film transistor TFT1can be turned on under the control of the first control signal and turned off under the control of the second control signal, and the second thin film transistor TFT2can be turned on under the control of the second control signal and turned off under the control of the first control signal. The input terminal of the first thin film transistor TFT1is used to load the first control voltage V1, the output terminal of the first thin film transistor TFT1is electrically connected to the first reflective electrode301, and the control terminal of the first thin film transistor TFT1is electrically connected to a control lead Gate. The input terminal of the second thin film transistor TFT2is used to load the second control voltage V2, the output terminal of the second thin film transistor TFT2is electrically connected to the first reflective electrode301, and the control terminal of the second thin film transistor TFT2is electrically connected to the control lead Gate.

When the first control signal is applied to the control lead Gate, the first thin film transistor TFT1is turned on and the second thin film transistor TFT2is turned off, and the first control voltage V1is applied to the first reflective electrode301through the first thin film transistor TFT1. When the second control signal is applied to the control lead Gate, the second thin film transistor TFT2is turned on and the first thin film transistor TFT1is turned off, and the second control voltage V2is applied to the first reflective electrode301through the second thin film transistor TFT2.

Optionally, the input terminal of the first thin film transistor TFT1may be used to load the first power supply voltage (VDD) as the first control voltage, that is, the input terminal of the first thin film transistor TFT1may be electrically connected to the power lead of the array substrate.

Optionally, the first driving circuit201may also be provided with a voltage divider circuit, and the input terminal of the voltage divider circuit is used to load the first power supply voltage (VDD), that is, the input terminal of the voltage divider circuit may be electrically connected to the power lead of the array substrate. The output terminal of the voltage divider circuit can be electrically connected to the input terminal of the first thin film transistor TFT1. In this way, a certain voltage can be obtained through the voltage divider circuit, for example, 0.5VDD (half of the first power supply voltage) can be obtained as the first control voltage.

Optionally, the input terminal of the second thin film transistor TFT2may be electrically connected to the common electrode layer600. In this way, the second control voltage may be the same as the voltage on the common electrode layer600, that is, both of them are the second power supply voltage (VSS).

As shown inFIG.4, the second driving circuit202is used to apply a required current or voltage to the second reflective electrode302, to drive the light-emitting unit410to emit light. In an embodiment of the present disclosure, the second driving circuit202may be an active driving circuit, which may be provided with a thin film transistor. Optionally, the second driving circuit202may also be provided with electronic components such as storage capacitors. The thin film transistor may be LTPS-TFT (low temperature polysilicon-thin film transistor) or Oxide-TFT (oxide-thin film transistor), for example, IGZO-TFT, which is not limited in the present disclosure. The thin film transistor may be of a top gate type or a bottom gate type, which is not limited in the present disclosure.

Optionally, when the light-emitting layer is provided with a plurality of light-emitting units410, the reflective electrode layer may be provided with a plurality of second reflective electrodes302in one-to-one correspondence with each light-emitting unit410, wherein any one of the light-emitting units410is provided on a surface of the corresponding second reflective electrode302away from the base substrate100. The driving circuit layer is provided with a plurality of second driving circuits202, and the output terminal of each second driving circuit202is electrically connected to each second reflective electrode302in one-to-one correspondence. In this way, the plurality of second driving circuits202drive the plurality of light-emitting units410in one-to-one correspondence, so that each light-emitting unit410can emit light independently and controllably.

The second driving circuit202can be selected and determined according to the type of the light-emitting unit410and the performance requirements of the array substrate. For example, when the light-emitting unit410is an LED (light-emitting diode), a micro LED, an OLED (organic light-emitting diode), etc., the second driving circuit202may select a driving circuit for outputting a driving current. When the light-emitting unit410is a liquid crystal cell or the like, the second driving circuit202may select a driving circuit for outputting a driving voltage.

Below, a specific implementation manner of the second driving circuit202is exemplarily provided to further exemplify the structure and principle of the second driving circuit202.

As shown inFIG.8, the exemplary second driving circuit202may be a 2T1C (two thin film transistors and one storage capacitor) architecture, which includes a driving transistor TFT3, a data writing transistor TFT4and a storage capacitor Cst. The driven light-emitting unit410may be a micro LED. The input terminal (source) of the driving transistor TFT3is used to load the first power supply voltage (VDD), the output terminal (drain) of the driving transistor TFT3is used to connect the second reflective electrode302, and the control terminal (gate) of the driving transistor TFT3is electrically connected to the first electrode of the storage capacitor Cst. The input terminal (source) of the data writing transistor TFT4is used to load the data voltage signal Vdata, the output terminal (drain) of the data writing transistor TFT4is electrically connected to the first electrode of the storage capacitor Cst, and the control terminal (gate) of the data writing transistor TFT4is used to load the scan signal Vgate. The second electrode of the storage capacitor Cst is used to load the second power supply voltage (VSS). The light-emitting unit410is disposed between the second reflective electrode302and the common electrode layer600, and the common electrode layer600is also applied with a second power supply voltage (VSS).

In a charging phase, the scan lead applies the scan signal Vgateto the control terminal of the data writing transistor TFT4, so that the data writing transistor TFT4is turned on. The data lead applies the data voltage signal Vdatato the input terminal of the data writing transistor TFT4, so that the data voltage signal Vdatais applied to the first electrode of the storage capacitor Cst and written into the storage capacitor Cst. Since the first electrode of the storage capacitor Cst is electrically connected to the control terminal of the driving transistor TFT3, the driving transistor TFT3can output a driving current under the control of the voltage on the first electrode of the storage capacitor Cst. The driving current passes through the second reflective electrode302and the light-emitting unit410(micro LED) and flows to the common electrode layer600, and the light-emitting unit410emits light under the driving of the driving current. In a light-emission maintaining phase, after the scan wire is no longer loaded with the scan signal Vgate, the data writing transistor TFT4is turned off, so the storage capacitor Cst can maintain the voltage on its first electrode unchanged, so that the driving transistor TFT3can continuously output the driving current, and the light-emitting unit410continuously emits light.

It is understandable that the driving circuit of the 2T1C architecture described above is only an example of the second driving circuit202. In other cases, the second driving circuit202may also have other circuit structures. For example, the second driving circuit202may adopt a 5T1C architecture, 6T1C architecture, 7T1C architecture, 4T2C architecture, 5T2C architecture, etc., which will not be described in this disclosure in detail.

The reflective electrode layer300is provided with a first reflective electrode301. The first reflective electrode301, the electrochromic layer500and the common electrode layer600constitute a mirror reflective device controlled by the first driving circuit201.

In the first situation, a first control signal may be applied to the first driving circuit201, so that the first driving circuit201applies a first control voltage to the first reflective electrode301according to the first control signal. A first common voltage is applied to the common electrode layer600, so that a potential difference between the first reflective electrode301and the common electrode layer600is within a first preset range, so that the electrochromic layer500is in a transparent state. Referring toFIG.5, in the first situation, since the electrochromic layer500is in a transparent state, the ambient light can be irradiated to the first reflective electrode301and reflected by the first reflective electrode301, thereby making the array substrate have a mirror display function.

In a second situation, a second control signal may be applied to the first driving circuit201, so that the first driving circuit201applies a second control voltage to the first reflective electrode301according to the second control signal. A second common voltage is applied to the common electrode layer600, so that a potential difference between the first reflective electrode301and the common electrode layer600is within a second preset range, so that the electrochromic layer500is in an opaque state. Referring toFIG.6, in the second situation, since the electrochromic layer500is in an opaque state, ambient light cannot be irradiated to the first reflective electrode301, and cannot be reflected by the first reflective electrode301, which can suppress or eliminate the mirror reflection function of the array substrate, avoid the influence of the ambient light reflected by the array substrate on the display image, and improve the contrast of the image displayed by the array substrate.

Optionally, the first common voltage and the second common voltage may be the same or different.

The reflective electrode layer300is provided with a first reflective electrode301and a second reflective electrode302that are insulated from each other, to ensure that the image display function and the mirror display function of the array substrate are independent of each other.

In an embodiment of the present disclosure, as shown inFIG.9, an amount of the second reflective electrode302is multiple, and the first reflective electrode301may be formed with a plurality of hollowed-out first pixel windows310in one-to-one correspondence with each of the second reflective electrodes302, and any one of the second reflective electrodes302is arranged in the corresponding first pixel window310. In this way, the first reflective electrode301is arranged between any two second reflective electrodes302, which can increase the area of the first reflective electrode301, thereby ensuring that the array substrate has better mirror reflection ability.

The distance between the second reflective electrode302and the first reflective electrode301can be determined according to process requirements, pixel density, and the like. In an embodiment of the present disclosure, the distance between any one of the second reflective electrodes302and the first reflective electrode301is 1-10 microns, which can increase the area of the first reflective electrode301, increase the area ratio of the reflective electrode layer300with respect to the entire array substrate, and improve the mirror display effect of the array substrate, on the premise of guaranteeing the effective insulation between the second reflective electrode302and the first reflective electrode301. In some embodiments, the distance between any one of the second reflective electrodes302and the first reflective electrode301is 2-5 microns.

In an embodiment of the present disclosure, as shown inFIG.9, the first reflective electrode301may be an integral structure, that is, any two positions of the first reflective electrode301are electrically connected to each other. In this way, the area of the first reflective electrode301can be increased, and the entire first reflective electrode301can be controlled by one first driving circuit201, which simplifies the driving circuit layer200of the array substrate and the control method.

It can be understood that, in other implementations of the present disclosure, the first reflective electrode301may also be divided into a plurality of unconnected parts. Different parts of the first reflective electrode301may be connected to the output terminal of the same first driving circuit201at the same time, or they may be electrically connected to the output terminals of different first driving circuits201respectively.

As shown inFIG.9, a plurality of second reflective electrodes302are distributed in an array. Referring toFIGS.4and8, any second reflective electrode302can be used as a pixel electrode to cooperate with the corresponding light-emitting unit410, to drive the light-emitting unit410to emit light. In the embodiment, each second reflective electrode302is electrically connected to each second driving circuit202in one-to-one correspondence, so that each light-emitting unit410can be independently controlled by each second driving circuit202in one-to-one correspondence.

The material and thickness of the first reflective electrode301and the second reflective electrode302may be the same, so that the first reflective electrode301and the second reflective electrode302can be prepared in the same process simultaneously. For example, in an embodiment of the present disclosure, the reflective electrode layer300may be prepared by the following method.

A reflective electrode material layer is formed on the side of the driving circuit layer200away from the base substrate100; then the reflective electrode material layer is patterned to form a reflective electrode layer300, and the reflective electrode layer300is formed with a first reflective electrode301and a second reflective electrode302.

Optionally, the reflective electrode layer300should have a good reflective ability to ensure the reflective ability of the reflective electrode layer300, thereby ensuring the mirror display effect of the array substrate. Optionally, the reflectivity of the reflective electrode layer300is not less than 90%. In some embodiments, the reflectivity of the reflective electrode layer300is not less than 95%. In this way, it can ensure that the reflective electrode layer300, especially the second reflective electrode302, has a high reflectivity.

Optionally, the reflective electrode layer300is made of materials with good electrical conductivity, for example, metals, alloys, and other materials.

In an embodiment of the present disclosure, the material of the reflective electrode layer300may be a combination of one or more of silver, aluminum, molybdenum, titanium, and the like.

The light-emitting unit410can be an electroluminescent device such as LED, Micro LED, OLED, PLED, or other electroluminescent devices. Since the liquid crystal unit can be used to control whether light from the backlight source passes through and the intensity of the light passing through, the liquid crystal unit can also be regarded as the light-emitting unit410of the present disclosure.

In the present disclosure, the light-emitting unit410may be composed of anode and cathode electrodes and a functional layer disposed between the anode and cathode electrodes, or it may also only include the functional layer, and the second reflective electrode302and the common electrode layer600are used as anode and cathode electrodes.

For example, in an embodiment of the present disclosure, the light-emitting unit410may be a Micro LED, and two ends of the Micro LED are connected to the second reflective electrode302and the common electrode layer600, respectively. The LED includes a plurality of layers of stacked inorganic semiconductor layers to form a PN junction surface contact diode. One of the second reflective electrode302and the common electrode layer600serves as an anode, and the other serves as a cathode. When a forward bias is applied between the anode and the cathode, the current flows from the anode to the cathode through the Micro LED, and electrons and holes recombine in the active area of the Micro LED, making the Micro LED emit monochromatic light. Optionally, the thickness of the Micro LED is 3 to 5 microns.

Optionally, the light-emitting unit410in the array substrate includes a red light-emitting unit410, a green light-emitting unit410and a blue light-emitting unit410. Exemplarily, the red light-emitting unit410may include an AlGaAs layer, a GaAsP layer, an AlGaInP layer, and a GaP layer sequentially stacked on the surface of the second reflective electrode302away from the base substrate100. The surface of the GaP layer away from the base substrate100is electrically connected to the common electrode layer600. Exemplarily, the green light-emitting unit410may include an InGaN layer, a GaN layer, a GaP layer, an AlGaInP layer and an AlGaP layer sequentially stacked on the surface of the second reflective electrode302away from the base substrate100. The surface of the AlGaP layer away from the base substrate100is electrically connected to the common electrode layer600. Exemplarily, the blue light-emitting unit410may include a GaN layer, an InGaN layer and a ZnSe layer that are sequentially stacked on the surface of the second reflective electrode302away from the base substrate100. The surface of the ZnSe layer away from the base substrate100is electrically connected to the common electrode layer600.

Optionally, when the light-emitting unit410is a micro LED, each micro LED may be transferred to the corresponding second reflective electrode302through the mass transfer technology.

The electrochromic layer500can reversibly change its color or transparency under the change of the potential difference between the first reflective electrode301and the common electrode layer600. In the first situation, the potential difference between the first reflective electrode301and the common electrode layer600is within the first preset range, and the electrochromic layer500is in a transparent state. In the second situation, the electric potential difference between the first reflective electrode301and the common electrode layer600is within the second preset range, and the electrochromic layer500is in an opaque state.

The material of the electrochromic layer500may be an organic material or an inorganic material. In an embodiment of the present disclosure, the electrochromic layer500may use a metal oxide or a mixture of a plurality of metal oxides. For example, in an embodiment of the present disclosure, the material of the electrochromic layer500is a combination of one or more of tungsten oxide, molybdenum oxide, titanium oxide, vanadium oxide, and niobium oxide. For another example, in another embodiment of the present disclosure, the material of the electrochromic layer500is a combination of one or more of nickel oxide, iridium oxide, cobalt oxide, and rhodium oxide. Exemplarily, the material of the electrochromic layer500may be tungsten oxide.

The common electrode layer600is a transparent conductive electrode, so that the light emitted from the light-emitting unit410can emit out by passing through the common electrode layer600, and the ambient light can pass through the common electrode layer600to realize the mirror display of the array substrate. The material of the common electrode layer600may be a-Si (a-polysilicon), ITO (indium tin oxide), IZO (indium zinc oxide), carbon nanotubes and other transparent conductive materials. In an embodiment of the present disclosure, the material of the common electrode layer600is ITO.

As shown inFIG.2, the array substrate provided by the present disclosure may further include a pixel defining layer710, and the pixel defining layer710is provided on the side of the driving circuit layer200away from the base substrate100.

In an embodiment of the present disclosure, the light-emitting unit410may be a Micro LED. As shown inFIGS.2and10, the pixel defining layer710is formed with a plurality of hollowed-out second pixel windows711in one-to-one correspondence with each second reflective electrode302, and any one of the second reflective electrodes302is provided in the corresponding second pixel window711. That is, the second pixel window711exposes the corresponding second reflective electrode302. The first reflective electrode301is disposed on the side of the pixel defining layer710away from the base substrate100. In this way, the pixel defining layer710may be formed with a second pixel window711for docking with the Micro LED which serves as the light-emitting unit410.

Optionally, the thickness of the pixel defining layer710can be determined according to the thickness of the Micro LED, so that the second pixel window711can accommodate each Micro LED. In an embodiment of the present disclosure, the thickness of the pixel defining layer710is not less than the thickness of the Micro LED.

Optionally, the material of the pixel defining layer710may be a black material.

Optionally, after the pixel defining layer710is formed, a reflective electrode material layer covering a side of the pixel defining layer710away from the base substrate100can be formed by sputtering or evaporation or the like, and then the reflective electrode material layer is patterned, and in turn, the first reflective electrode301is obtained and each second reflective electrode302located in each second pixel window711in one-to-one correspondence is formed.

When the light-emitting unit410is another type of light-emitting device, such as an OLED or PLED, the second pixel window711of the pixel defining layer710may be used to define the light-emitting area of the light-emitting unit410. For example, the second reflective electrode302may be formed on the side of the driving circuit layer200away from the base substrate100first, and then the pixel defining layer710may be formed on the side of the second reflective electrode302away from the base substrate100. The second pixel window711of the pixel defining layer710exposes each second reflective electrode302or exposes a part of the second reflective electrodes302.

As shown inFIGS.2and11, the array substrate of the present disclosure may further include a passivation protection layer720. The passivation protection layer720is disposed between the reflective electrode layer300and the common electrode layer600. The passivation protection layer720is formed with a plurality of hollowed-out third pixel windows721in one-to-one correspondence with each light-emitting unit410, and any light-emitting unit410is embedded in the corresponding third pixel window721. In this way, when the light-emitting unit410is a micro LED, the passivation protection layer720will surround the Micro LED so as to prevent short-circuit of the common electrode layer600and other film layers (for example, each quantum well layer) of the micro LED, and avoid short-circuit of the common electrode layer600and the reflective electrode layer300.

The material of the passivation protection layer720may be an organic insulating material or an inorganic insulating material. For example, in an embodiment of the present disclosure, the material of the passivation protection layer720may be PMMA (polymethyl methacrylate) or PI (polyimide).

Optionally, after the massive transfer of the Micro LEDs is completed, each passivation protection layer720surrounding each Micro LED can be formed, so that each Micro LED only exposes the surface of the film layer away from the base substrate100, without exposing other film layers, which avoids the short-circuit of other film layers and the common electrode when the common electrode layer600is formed. It can be understood that the portion of the second reflective electrode302not covered by the Micro LED may be covered by the passivation protection layer720, to prevent the common electrode layer600and the second reflective electrode302from being short-circuited.

In an embodiment of the present disclosure, the array substrate of the present disclosure may further include an encapsulation layer, and the encapsulation layer covers the side of the common electrode layer600away from the base substrate100, to protect the common electrode layer600.

In an embodiment of the present disclosure, the array substrate of the present disclosure may further include a touch layer, and the touch layer is disposed on a side of the common electrode layer600away from the base substrate100to realize touch control of the array substrate. In some embodiments, the driving circuit layer200is further provided with a third driving circuit, and the third driving circuit is electrically connected to the touch layer and used for driving the touch layer.

In an embodiment of the present disclosure, the array substrate of the present disclosure may further include a fingerprint identification layer, which is provided on the side of the common electrode layer600away from the base substrate100to realize fingerprint identification. In some embodiments, the driving circuit layer200is further provided with a fourth driving circuit, which is electrically connected to the fingerprint recognition layer and used to drive the fingerprint recognition layer.

The present disclosure also provides a method for preparing the array substrate. As shown inFIG.12, the method for preparing the array substrate includes:

step S110, providing a base substrate100;

step S120, forming a driving circuit layer200on a side of the base substrate100, wherein the driving circuit layer200is provided with a first driving circuit201and a second driving circuit202;

step S130, forming a reflective electrode layer300on a side of the driving circuit layer200away from the base substrate100, wherein the reflective electrode layer300is provided with a first reflective electrode301and a second reflective electrode302, the first reflective electrode301is electrically connected to an output terminal of the first driving circuit201and insulated from the second reflective electrode302, and the second reflective electrode302is electrically connected to an output terminal of the second driving circuit202;

step S140, forming a light-emitting layer, wherein the light-emitting layer includes a light-emitting unit410disposed on a surface of the second reflective electrode302away from the base substrate100;

step S150, forming an electrochromic layer500, wherein the electrochromic layer500covers a surface of the first reflective electrode301away from the base substrate100; and

step S160, forming a common electrode layer600, wherein the common electrode layer600covers a surface of the electrochromic layer500away from the base substrate100and a surface of the light-emitting unit410away from the base substrate100.

The preparation method of the array substrate provided in the present disclosure can prepare any of the array substrates provided in the above-mentioned array substrate embodiments. The principle, effect and detail of the preparation method are described in detail in the above-mentioned array substrate embodiments, or they may be reasonably deduced based on the description in the above-mentioned array substrates, which is not repeated in the present disclosure.

It should be noted that although various steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that these steps must be performed in the specific order, or that all the steps shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step to be executed, and/or one step may be decomposed into multiple steps to be executed, etc., which all should be regarded as a part of the present disclosure.

The embodiments of the present disclosure also provide a display panel, which includes any of the array substrates described in the above-mentioned array substrate embodiments. The display panel may be an OLED display panel, a PLED display panel, a Micro LED display panel, or other types of display panels. Since the display panel has any of the array substrates described in the above-mentioned array substrate embodiments, it has the same beneficial effects, which will not be repeated in this disclosure.

The present disclosure also provides a driving method of a display panel, which is used to drive any one of the display panels described in the foregoing display panel embodiments. The driving method of the display panel includes following steps.

In the first situation, a first control signal is applied to the first driving circuit201, so that the first driving circuit201applies a first control voltage to the first reflective electrode301according to the first control signal. A first common voltage is applied to the common electrode layer600, so that a potential difference between the first reflective electrode301and the common electrode layer600is within a first preset range, so that the electrochromic layer500is in a transparent state. In this way, in the first situation, since the electrochromic layer500is in a transparent state, ambient light can be irradiated to the first reflective electrode301and reflected by the first reflective electrode301, thereby making the array substrate have a mirror display function.

In a second situation, a second control signal is applied to the first driving circuit201, so that the first driving circuit201applies a second control voltage to the first reflective electrode301according to the second control signal. A second common voltage is applied to the common electrode layer600, so that a potential difference between the first reflective electrode301and the common electrode layer600is within a second preset range, so that the electrochromic layer500is in an opaque state. In this way, in the second situation, since the electrochromic layer500is in an opaque state, ambient light cannot be irradiated to the first reflective electrode301, and cannot be reflected by the first reflective electrode301, which can suppress or eliminate the mirror reflection function of the array substrate, avoid the influence of the ambient light reflected by the array substrate on the display image, and improve the contrast of the image displayed by the array substrate.

The principle, detail, and effect of the driving method are described and introduced in detail in the above-mentioned implementation of the array substrate, which will not be repeated in this disclosure.

It should be understood that the present disclosure does not limit its application to the detailed structure and arrangement of components proposed in this specification. The present disclosure can have other embodiments, and can be implemented and executed in various ways. The aforementioned deformations and modifications fall within the scope of the present disclosure. It should be understood that the present disclosure disclosed and defined in this specification extends to all alternative combinations of two or more individual features mentioned or well-understood in the text and/or drawings. All these different combinations constitute multiple alternative aspects of the present disclosure. The embodiments of the present specification illustrate the best way known for implementing the present disclosure, and will enable those skilled in the art to utilize the present disclosure.