CN115000140A

CN115000140A - Display panel and electroluminescent device

Info

Publication number: CN115000140A
Application number: CN202210615755.7A
Authority: CN
Inventors: 严哲
Original assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-09-02

Abstract

The embodiment of the invention provides a display panel and an electroluminescent device. Including array substrate, first electrode layer, luminous functional layer, second electrode layer, be provided with the light regulation and control layer in this regulation and control region of luminous functional layer, a side orientation on the light regulation and control layer first electrode layer sets up, the another side orientation on light regulation and control layer the setting of second electrode layer, when insert different voltages on first electrode layer and second electrode layer, under the effect of this voltage difference, the layer of should adjusting and control light can change under transparent and non-transparent state to realize display panel transparent display, in order to improve display effect.

Description

Display panel and electroluminescent device

Technical Field

The present invention relates to the field of display panel manufacturing technologies, and in particular, to a display panel and an electroluminescent device.

Background

With the development of display panel manufacturing technology, people have made higher demands on the display effect and the comprehensive performance of the display panel and the display device.

Display panels and light emitting devices are gradually extended in various fields, such as transparent display fields. The transparent display is characterized in that the display has a certain degree of light penetrability, so that not only can a picture displayed by the display be seen, but also information behind the display can be seen, and the transparent display function is realized. The transparent display has the advantage of being displayed or not displayed under different conditions according to the use requirements of a user. At present, transparent displays have begun to be applied to high-end display fields such as window glass, shop windows, Augmented Reality (AR), Virtual Reality (VR), and the like. In order to achieve the transparent display effect of the device, in the prior art, when a transparent display panel is manufactured and formed, a transparent display unit is generally added around a light-emitting pixel of the display panel, and light transmittances in different areas are adjusted by the transparent display unit, so that light on the back of a screen can pass through the transparent display unit to reach the front of the screen, thereby achieving the purpose of transparent display. However, in the existing design, the transparent material corresponding to the transparent display unit is always kept at the same transparency, and when the application scene of the display panel is changed, the light transmittance in the transparent display unit does not change, so that the transparent display effect of the display panel is reduced, and the improvement of the comprehensive performance of the panel is not facilitated.

In summary, when the display panel works under different conditions, the transparent display effect of the transparent display panel prepared and formed in the prior art cannot meet the requirements of users, and thus the comprehensive performance of the transparent display panel is improved.

Disclosure of Invention

The embodiment of the invention provides a display panel and an electroluminescent device. The problem that the transparent display effect is not ideal when the display panel realizes transparent display is effectively solved.

To solve the above technical problem, the present invention provides a display panel, including:

an array substrate;

a first electrode layer disposed over the array substrate;

a light emitting functional layer disposed on the first electrode layer; and the number of the first and second groups,

a second electrode layer disposed on the light emitting function layer;

the light emitting functional layer comprises a control area, a light control layer is arranged in the control area, one side face of the light control layer faces to the first electrode layer, the other side face of the light control layer faces to the second electrode layer, light transmittance corresponding to the light control layer changes along with changes of voltage differences between the first electrode layer and the second electrode layer.

According to an embodiment of the present invention, the first electrode is connected to a first voltage, and the second electrode is connected to a second voltage;

wherein the first voltage and the second voltage have different voltage values;

when the voltage difference between the first electrode and the second electrode is greater than zero, the light regulation layer is a transparent layer, and when the voltage difference between the first electrode and the second electrode is equal to zero, the light regulation layer is a non-transparent layer.

According to an embodiment of the present invention, the first voltage is a positive voltage, and the second voltage is 0 or a negative voltage.

According to an embodiment of the present invention, the light emitting function layer includes a pixel region and a non-pixel region, the non-pixel region is disposed at one side of the pixel region;

the light modulation layer is arranged on the first electrode layer, and the light modulation layer is arranged in the non-pixel region.

According to an embodiment of the present invention, an area of an orthographic projection of the first electrode on the surface of the array substrate is larger than an area of an orthographic projection of the light modulation layer on the surface of the array substrate.

According to an embodiment of the present invention, the material of the light control layer is an electro-transparent variable material.

According to an embodiment of the present invention, under different voltage differences, the light transmittance of the light modulation layer in the modulation region is different.

According to an embodiment of the present invention, the light emitting function layer includes a through hole, the through hole is correspondingly disposed in the non-pixel region, and the light control layer is disposed in the through hole.

According to an embodiment of the present invention, a reflective layer is further disposed on a sidewall of the through hole, and the reflective layer is disposed around the light control layer.

According to a second aspect of embodiments of the present invention, there is also provided an electroluminescent device, comprising:

a display panel; and (c) a second step of,

a light coupling layer disposed over the display panel;

the display panel is provided in the embodiment of the application.

The embodiment of the invention has the following beneficial effects: compared with the prior art, the embodiment of the invention provides a display panel and an electroluminescent device. The display panel comprises an array substrate, a first electrode layer, a light-emitting functional layer and a second electrode layer, wherein one side face of the light control layer faces towards the first electrode layer, the other side face of the light control layer faces towards the second electrode layer, when different voltages are connected to the first electrode layer and the second electrode layer, a voltage difference is formed in an area corresponding to the light control layer by the first electrode layer and the second electrode layer, and the light control layer can be changed in a transparent state and a non-transparent state under the action of the voltage difference, so that the transparent display effect of the display panel is achieved. The display panel provided by the embodiment of the application can regulate and control the light regulating and controlling layer according to different use conditions so as to achieve the optimal transparent display effect.

Drawings

In order to illustrate the embodiments or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the application, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic view of a film structure of a display panel according to an embodiment of the present disclosure;

fig. 2 is an optical path diagram of a transparent display device provided in an embodiment of the present application;

fig. 3 is a schematic diagram illustrating an effect of the transparent display device according to an embodiment of the present disclosure;

fig. 4 is a schematic plan view of the array substrate according to the embodiment of the present disclosure.

Detailed Description

The following disclosure provides different embodiments or examples to implement different structures of the present invention, which are shown in the drawings of the embodiments of the present invention. In order to simplify the present disclosure, specific example components and arrangements are described below. In addition, the present invention provides examples of various specific processes and materials, and one of ordinary skill in the art will recognize that other processes may be used. All other embodiments obtained by a person skilled in the art without making any inventive step are within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

With the development of display panel preparation technology, people put higher demands on the quality and performance of display panels. Such as a transparent display type device, has been proposed to further improve the function and application field of the display panel.

The embodiment of the application provides a display panel and an electroluminescent device, so as to effectively improve the application range and the display effect of the transparent display panel when the display panel performs transparent display.

As shown in fig. 1, fig. 1 is a schematic view of a film structure of a display panel according to an embodiment of the present disclosure. In the embodiment of the present application, the display panel includes an array substrate 30, a first electrode layer 201 disposed on the array substrate 30, a light emitting function layer 31 disposed on the first electrode layer 201, and a second electrode layer 222 disposed on the light emitting function layer 31.

Specifically, in the embodiment of the present application, the array substrate 30 may include a thin film transistor array substrate. In the array substrate 30, a plurality of thin film transistors 40 are included, and a control signal is provided to the light emitting function layer 31 through the plurality of thin film transistors 40.

In the embodiment of the present application, the array substrate 30 includes a substrate 100, a buffer layer 102, a first insulating layer 103, a first gate insulating layer 104, a second gate insulating layer 105, a planarization layer 106, and an active layer 303, a source 301, a drain 302, a first gate 304, and a second gate 305 of a thin film transistor.

Wherein the buffer layer 102 is disposed on the substrate 100, the active layer 303 is disposed on the buffer layer 102, and the first insulating layer 103 is disposed on the buffer layer 102 and covers the active layer 303.

Meanwhile, the first gate electrode 304 is disposed on the first insulating layer 103, the first gate insulating layer 104 is disposed on the first insulating layer 103, and the first gate insulating layer 104 completely covers the first gate electrode 304. The second gate electrode 305 is disposed on the first insulating layer 103, the second gate insulating layer 105 is disposed on the first gate insulating layer 104, and the second gate insulating layer 105 completely covers the second gate electrode 305.

Specifically, in the embodiment of the present application, vias are further disposed at the first position, and the source electrode 301 and the drain electrode 302 of the thin film transistor are electrically connected to the active layer 303 through the corresponding vias.

In the embodiment of the present application, a double-gate thin film transistor including a first gate electrode 304 and a second gate electrode 305 will be described as an example. Meanwhile, the thin film transistor may be provided in a single gate type structure.

Meanwhile, the planarization layer 106 is disposed on the second gate insulating layer 105, and the planarization layer 106 completely covers the source/drain electrodes of the thin film transistor.

In the embodiment of the present application, the display panel includes a light-emitting region 10 and a non-light-emitting region 20. Specifically, the light-emitting region 10 is disposed on the upper side of the non-light-emitting region 20. The light-emitting region 10 may be a pixel region of a display panel, and the non-light-emitting region 20 is a non-pixel region of the display panel. That is, the light-emitting region 10 corresponds to a pixel region where a light-emitting sub-pixel is provided, and the non-light-emitting region 20 is not provided with a light-emitting sub-pixel, that is, the region is a non-pixel region.

In the following embodiments, the light emitting sub-pixel may be a plurality of sub-pixels with different colors. Meanwhile, the pixel region includes a red sub-pixel region 51, a blue sub-pixel region 52, and a green sub-pixel region 53 which are disposed at intervals.

A pixel defining layer 202, a first electrode layer 201, and an anode 101 are further disposed on the planarization layer 106. The pixel defining layer 202 is disposed on the planarization layer 106, and the pixel defining layer 202 at least partially covers the first electrode layer 201 and the anode 101. The first electrode layer 201 and the anode 101 are disposed in the same layer. And, the anode 101 is electrically connected to the drain 302 of the thin film transistor 40 through a corresponding via structure, thereby transmitting a control signal to the anode through the thin film transistor.

Preferably, both the first electrode layer 201 and the anode 101 can be patterned. The anode 101 is disposed in a pixel region of the display panel, and the first electrode layer is disposed in a non-pixel region. Therefore, the shielding of the first electrode layer 201 to light is reduced, and the light emitting and displaying effects of the display panel are effectively improved.

Further, a light emitting function layer 31 is provided on the pixel defining layer 202. In the embodiment of the present application, the light emitting functional layer 31 may be a stacked structure of multiple layers. The light emission of the display panel is realized by the light emission functional layer 31.

Specifically, the light-emitting functional layer 31 may include: a hole injection layer 203, a hole transport layer 204, a light emitting layer 210, a color resist 211, a hole blocking layer 205, an electron transport layer 206, an electron injection layer 207, and a second electrode layer 222.

Wherein the hole injection layer 203 is disposed on the pixel defining layer 202, and the hole transport layer 204 is disposed on the hole injection layer 203. Meanwhile, the light emitting layer 210 is disposed on the hole transport layer 204, and the color resist 211 is disposed on the light emitting layer 210. And the hole blocking layer 205 is disposed on the hole transport layer 204 and completely covers the color resist 211. And the electron transport layer 206 is disposed on the hole blocking layer 205, the electron injection layer 207 is disposed on the electron transport layer 206, and at the same time, the second electrode layer 222 is disposed on the electron injection layer 207.

In the embodiment of the present application, the light emitting layer 210 and the color resistor 211 are at least correspondingly disposed in the pixel region corresponding to the light emitting function layer 31. For example, in the red sub-pixel region 51, a red sub-pixel and a red color resistor are provided. And color resistances with different colors can be respectively arranged in adjacent pixel areas, thereby realizing the color display of the display panel. Preferably, the setting can be performed according to the actual function of the display panel, and is not limited herein.

Correspondingly, in the embodiment of the present application, a first via hole 212 is further disposed in the light emitting function layer 31. The first via hole 212 is correspondingly disposed in the non-pixel region. Meanwhile, the first via hole 212 penetrates through the light emitting function layer 31, and at least a part of the thickness film of the pixel defining layer 202 is also formed with the first via hole 212. The first electrode layer 201 is exposed through the first via hole 212.

Further, a control region 266 is further included in the light-emitting functional layer 31. In the embodiment of the present application, the modulation region 266 may be disposed at least in the non-pixel region. Meanwhile, the first via hole 212 may be disposed in the modulation region 266, and in this embodiment, the display panel further includes a light modulation layer 213. The light modulation layer 213 can be disposed in the first via hole 212 and disposed along the thickness direction of the light emitting functional layer corresponding to the first via hole 212. Thus, the light modulating layer 213 fills the first via 212. Preferably, the thickness of the light modulation layer 213 may be the same as the height of the first via 212, thereby ensuring better uniformity.

In the following embodiments, the control region 266 can be overlapped with a non-pixel region, that is, in the following embodiments, the control region 266 is exemplified by the non-pixel region. In the embodiment, the light modulation layer 213 is disposed in the non-pixel region, so as to reduce the influence of the light modulation layer 213 on the light emitting effect. Meanwhile, one end of the light modulation layer 213 is connected to the first electrode layer 201, and the other end of the light modulation layer 213 is connected to the second electrode layer 222. That is, one side of the light modulation layer 213 is disposed toward the first electrode layer 201, and the other side is disposed toward the second electrode layer 222, that is, the upper and lower surfaces of the light modulation layer 213 correspond to different electrode layers, respectively.

Specifically, the first electrode layer 201 can be connected to a first voltage V1, and the second electrode layer 222 can be connected to a second voltage V2. In the embodiment of the present application, the first voltage value V1 may be different from the second voltage value V2.

When the display panel is in normal display and the transparent display is turned on, the voltage difference between the first voltage V1 and the second voltage V2 is greater than zero. Even if V1 > V2. At this time, the light modulation layer 213 becomes a transparent layer by the forward voltage difference. Since the light control layer 213 is a transparent film, light at the bottom of the array substrate 30 can propagate from the light control layer 213 corresponding to the non-pixel region and pass through the light control layer 213 to reach the front surface of the display panel. Thereby realizing the transparent display function of the display panel.

Further, in the embodiment of the present application, the material of the light modulation layer 213 can be selected to be an electro-transparent variable material. Under the action of voltage or electric field, molecules inside the material can move and rearrange, so that the light modulation layer 213 corresponding to the material has different display effects.

Further, in this embodiment of the application, the light modulation and control layer 213 may also be a color-changing material layer, and when the voltage difference is different, the light modulation and control layer 213 is changed into different colors, and when transparent display is performed, the color in the modulation and control region is adjusted, so that the visual effect of the light-emitting display region is improved, and the purpose of improving the performance of the panel is achieved.

Specifically, the light modulation layer 213 may have different transparency under different pressure differences δ V1-V2, so that the light modulation layer 213 may be switched between a transparent state and a non-transparent state according to different usage scenarios. When the voltage difference δ V between the first electrode layer 201 and the second electrode layer 222 is greater than zero, the light modulation layer is transparent, and the bottom and top lights can both pass through the light modulation layer. When the voltage difference between the first electrode layer 201 and the second electrode layer 222 is equal to zero, the light modulation layer is in a non-transparent state.

For example, when the screen needs to be lit and the transparent display function is turned on, the anode 101 and the first electrode layer are connected to a voltage a, and the second electrode layer is connected to a voltage b, where a > 0V and b < 0V, and at this time, the first electrode layer is equivalent to the anode and the second electrode layer is equivalent to the cathode. At this time, the light-emitting layer and the corresponding other film layers can emit light normally. Since the two ends of the electro-transparent variable material corresponding to the light modulation layer 213 are respectively connected to different voltages, a voltage difference δ > 0 occurs between the first electrode layer and the second electrode layer. Therefore, the light modulation layer 213 is subjected to the voltage difference, and the internal molecular structure is arranged to become transparent, so that the back light is incident on the electro-transparent variable material layer and penetrates to the front surface, and the transparent display is realized. In the embodiment of the present application, the first voltage may be a positive voltage, and the second voltage may be 0 or a negative voltage.

When the screen needs to be turned off and the transparent display function needs to be turned off, the voltage difference between the two ends of the light modulation control layer is adjusted. Specifically, the anode 101 and the first electrode layer 201 are both applied with the off voltage c, and the second electrode layer 222 is applied with the voltage d. Wherein c is 0 and d is 0. At this time, the light emitting layer 210 and the corresponding other film layers do not emit light, which is the same as that of the conventional display panel. And there is no voltage difference between the first electrode layer 201 and the second electrode layer 222, so the light modulation layer becomes opaque, and the light on the back side cannot pass through the electro-transparent variable material layer, so the whole screen is opaque.

Preferably, in the embodiment of the present invention, the difference between the voltage difference between the first electrode layer and the second electrode layer can be further controlled, for example, when the voltage difference δ is greater than a, the light modulation layer is in a transparent state, and when the voltage difference δ is less than B, the light modulation layer 213 is in a non-transparent state, or at this time, the light transmittance corresponding to the light modulation layer is smaller than the light transmittance corresponding to the voltage difference δ being greater than a. Wherein A > B.

Furthermore, in the embodiment of the present application, the voltages provided by the first electrode layer and the second electrode layer are only examples, and the light modulation layer is adjusted by controlling a voltage difference formed between the first electrode layer and the second electrode layer, so that the corresponding electrically variable transparent materials in the light modulation layer have different light transmittances. When the display panel is under different working conditions, the transparent display effect of the display panel is improved to the maximum extent.

In the embodiment, the first electrode layer 201 and the anode 101 are usually connected, however, the first electrode layer 201 is not connected to the anode 101, so as to ensure an adjustable voltage difference between the first electrode layer and the second electrode layer.

Further, in the embodiment of the present application, the first electrode layer 201 is a highly transparent electrode material. For example, the material may be transparent indium tin oxide, transparent Ag, or other transparent conductive metal material. Meanwhile, the second electrode layer 222 is a surface cathode, and the surface cathode is a transparent cathode.

Further, in the embodiment of the present application, in order to ensure the control effect on the light modulation layer 213, an area of an orthographic projection of the first electrode layer 201 on the surface of the array substrate 30 is larger than an area of an orthographic projection of the light modulation layer on the surface of the array substrate 30, so that the first electrode layer 201 can control the light modulation layers in all regions.

Preferably, as shown in fig. 2, fig. 2 is an optical path diagram of the transparent display device provided in the embodiment of the present application. In the embodiment, a reflective layer 333 may be disposed around the light modulation layer 213 to further increase the light within the light modulation layer. Specifically, the reflective layer 333 is disposed around the light modulating layer 213 and attached to the side of the first via. When the light passes through the light control layer, the light is emitted on the surface of the reflective layer 333 for multiple times, so as to further improve the intensity of the light passing through the light control layer and ensure the display effect of the device.

Meanwhile, as shown in fig. 3, fig. 3 is a schematic view of an effect of the transparent display device provided in the embodiment of the present application. When the display device 325 is a transparent display, light can penetrate into the display device from side a and pass out from side B, while light can penetrate into the display device 325 from side B and pass out from side a. Thereby realizing transparent display of the display device.

Further, in the embodiment of the present application, the display panel further includes a light coupling layer 208. The photo-coupling layer 208 is disposed on the second electrode layer 222. The light transmittance is further improved by the light coupling layer 208. Meanwhile, in the embodiment of the present application, when the optical coupling layer 208 is disposed, a reinforcing layer 209 may be further disposed when the optical coupling layer 208 is disposed. Specifically, the enhancement layer 209 can be a layer of LiF material.

In the embodiment of the present application, when the light control layer 213 is disposed, the light control layer 213 is correspondingly disposed in the non-pixel region of the light emitting function layer, so that when the transparent display is implemented, light can penetrate from the non-pixel region and change the non-pixel region into the transparent region.

As shown in fig. 4, fig. 4 is a schematic plan view of the array substrate according to the embodiment of the present disclosure. The light modulation layer 213 is provided in the non-light emitting region 20 of the array substrate 30. In the light emitting region 10, light emitting function layers are provided correspondingly. When the transparent display is implemented, the light modulation and control layer 213 in the non-light-emitting region 20 is converted into a transparent film layer, so that the light at the bottom of the array substrate can be transmitted out, and the light-emitting region 10 still can emit light for display. And transparent display is realized.

Further, in the embodiment of the present application, when the display panel corresponding to the array substrate is prepared, the high transparent electrode is deposited on the whole surface, that is, the first electrode layer 201 is deposited; etching a light emitting region corresponding to the first electrode layer 201 to form a via hole; then, a light control layer 213 is deposited on the whole surface, and then a mask is used to etch the via holes occupied by the pixel defining layer 202 and the anode 101. Specifically, the groove on the light-emitting control layer is etched, the via hole on the first electrode layer 201 is etched, the anode is deposited in the via hole, the pixel defining layer is deposited, and the excess portion is etched, so that the annular pixel defining layer 202 capable of wrapping the anode 101 is formed. The structural state of the anode and the pixel defining layer wrapping the anode and the anode 101 outside the annular pixel defining layer are finally presented. The sectional view is shown in fig. 1, and the top view is shown in fig. 4. Note that the light control layer in the top view is consistent with the anode 101 in shape, but has a smaller area.

Further, the display panel provided in the embodiment of the present application can adjust the light transmittance of the light modulation layer according to different usage scenarios. If the screen of the display panel is closed, the voltage difference between the first electrode layer and the second electrode layer can be adjusted, and the non-pixel area is in a transparent state, so that the display panel is suitable for different use working conditions. Preferably, when the voltage difference between the first electrode layer and the second electrode layer is adjusted, the transparent state of the light modulation layer and the voltage difference can be in a positive correlation adjustment relationship. I.e., the transmittance of the transparent state increases with an increase in the voltage difference, thereby improving the display effect of the display device.

Preferably, the embodiment of the application further provides a display device. The display device may be an electroluminescent display device. And the device may be a transparent display device. When the display device displays normally, the non-pixel area is in a transparent state, thereby realizing the transparent effect of the display device. Wherein, the display device is provided with the display panel. The display panel is an array substrate provided in the embodiment of the present application. The display device may be any product or component having a display function or a touch function, such as a mobile phone, a computer, electronic paper, a display, a notebook computer, a digital photo frame, and the like, and the specific type thereof is not particularly limited.

In summary, the display panel and the display device provided by the embodiments of the present invention are described in detail above, and the principle and the implementation manner of the present invention are described herein by applying specific examples, and the description of the above embodiments is only used to help understanding the technical solution and the core idea of the present invention; although the present invention has been described with reference to the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A display panel, comprising:

an array substrate;

a first electrode layer disposed over the array substrate;

a second electrode layer disposed on the light emitting function layer;

2. The display panel according to claim 1, wherein the first electrode layer is connected to a first voltage, and the second electrode layer is connected to a second voltage;

wherein the first voltage and the second voltage have different voltage values;

when the voltage difference between the first electrode layer and the second electrode layer is greater than zero, the light regulation layer is a transparent layer, and when the voltage difference between the first electrode layer and the second electrode layer is equal to zero, the light regulation layer is a non-transparent layer.

3. The display panel according to claim 2, wherein the first voltage is a positive voltage, and the second voltage is 0 or a negative voltage.

4. The display panel according to claim 1, wherein the light-emitting functional layer further comprises a pixel region and a non-pixel region, the non-pixel region being provided on one side of the pixel region;

5. The display panel according to claim 4, wherein an area of an orthographic projection of the first electrode on the surface of the array substrate is larger than an area of an orthographic projection of the light modulation layer on the surface of the array substrate.

6. The display panel of claim 1, wherein the material of the light modulation layer is an electro-transparent variable material.

7. The display panel according to claim 6, wherein the light transmittance of the light modulating layer in the modulating region is different under different voltage differences.

8. The display panel according to claim 1, wherein the light emitting function layer comprises a via hole, the through hole is correspondingly disposed in the control region, and the light control layer is disposed in the via hole.

9. The display panel of claim 8, wherein a reflective layer is disposed on a sidewall of the through hole, and the reflective layer is disposed around the light modulation layer.

10. An electroluminescent device, comprising:

a display panel; and the number of the first and second groups,

a light coupling layer disposed over the display panel;

wherein the display panel is as claimed in any one of claims 1 to 9.