Organic electroluminescent device, preparation method thereof and electronic device

Abstract

The application belongs to the technical field of organic semiconductor, and provides an organic electroluminescent device, a preparation method thereof and an electronic device. The organic electroluminescent device comprises a substrate, a first electrode layer with a preset pattern formed on the substrate, the preset pattern comprising a first region, a second region and a third region which are not connected with each other, the area of the second region and the area of the third region being smaller than the area of the first region, a sensing unit arranged on the substrate, one end of the sensing unit being connected with the first electrode corresponding to the second region, and the other end of the sensing unit being connected with the first electrode corresponding to the third region, current being transmitted between the first electrode corresponding to the second region and the first electrode corresponding to the third region through the sensing unit, and the conductive performance of the sensing unit changing when the sensing unit is deformed, an organic light-emitting layer formed on the first electrode corresponding to the first region and the second region, and a second electrode layer formed on the organic light-emitting layer. The application can determine the bending degree of the organic electroluminescent device according to the light-emitting condition.

Description

Technical Field

[0001] This application relates to the field of organic semiconductor technology, specifically to organic electroluminescent devices, their fabrication methods, and electronic devices. Background Technology

[0002] Currently, due to the high technical difficulty and cost of flexible display technology, flexible display devices cannot yet replace OLED (Organic Light-Emitting Diode) screens based on glass substrates. However, the inherent fragility and inflexibility of glass substrates also limit the further development of OLED screens. In particular, bending glass substrate OLED screens is problematic because the limited bending angle of the glass substrate can damage the screen if the bending angle is not properly controlled. Summary of the Invention

[0003] In view of this, embodiments of this application provide an organic electroluminescent device, a method for fabricating the same, and an electronic device, which enables the luminescence of the organic electroluminescent device to change with the degree of bending, thereby enabling the degree of bending to be determined based on the luminescence.

[0004] To achieve the above objectives, this application adopts the following technical solution:

[0005] In a first aspect, embodiments of this application provide an organic electroluminescent device, comprising:

[0006] Base;

[0007] A first electrode layer with a preset pattern is formed on a substrate; wherein the preset pattern includes a first region, a second region, and a third region that are not interconnected, and the areas of the second region and the third region are both smaller than the area of ​​the first region;

[0008] A sensing unit is disposed on a substrate, with one end connected to a first electrode corresponding to a second region and the other end connected to a first electrode corresponding to a third region; wherein, electrons flow through the sensing unit between the first electrode corresponding to the second region and the first electrode corresponding to the third region, and the conductivity of the sensing unit changes when it is deformed.

[0009] An organic light-emitting layer is formed on the first electrode corresponding to the first region and the second region;

[0010] The second electrode layer is formed on the organic light-emitting layer.

[0011] In this embodiment, after the organic electroluminescent device is energized, the current can be transmitted through a first transmission path and a second transmission path. The first transmission path consists of: a first electrode corresponding to a first region, an organic light-emitting layer corresponding to the first region, and a second electrode layer. The second transmission path consists of: a first electrode corresponding to a third region, a sensing unit, a first electrode corresponding to a second region, and an organic light-emitting layer corresponding to the second region and a second electrode layer. Therefore, the organic light-emitting layer also has a first light-emitting region and a second light-emitting region. The first light-emitting region is the region of the organic light-emitting layer corresponding to the first region, and the second light-emitting region is the region of the organic light-emitting layer corresponding to the second region.

[0012] During the operation of an organic light-emitting device (OLED), if the OLED is bent, the sensing unit will deform accordingly, and the conductivity of the sensing unit will change. This causes the current in the first transmission path to differ from the current in the second transmission path, resulting in different light emission patterns in the first and second light-emitting regions. As the degree of bending of the OLED increases, the conductivity of the sensing unit changes with the deformation, further causing the light emission pattern of the second light-emitting region to change with the degree of bending. Therefore, the degree of bending of the OLED can be determined based on the light emission pattern of the second light-emitting region.

[0013] For example, the first electrode can be an anode and the second electrode can be a cathode; or, the first electrode can be a cathode and the second electrode can be an anode.

[0014] In some possible implementations, the sensing unit includes multiple silicon nanowires disposed between a second region and a third region, and a first electrode corresponding to the second region and a first electrode corresponding to the third region are electrically connected through the multiple silicon nanowires.

[0015] For example, the aforementioned plurality of silicon nanowires are coated with optical adhesive, and the aforementioned plurality of silicon nanowires and the aforementioned optical adhesive constitute the aforementioned sensing unit.

[0016] In some embodiments, the second electrode layer also covers the sensing unit, which can provide a certain degree of fixation for the sensing unit. The pattern of the second electrode layer differs from that of the first region; it is a rectangle that covers the first region, the second region, and the region corresponding to the sensing unit, and the second electrode layer does not contact the first electrode corresponding to the third region.

[0017] In some embodiments, the first electrode layer may be made of a composite material of PEDOT, CNT, or AgNWs and resin.

[0018] In some embodiments, the substrate is a glass substrate with a thickness less than a threshold. For example, the substrate may be a glass substrate with a thickness less than or equal to 0.2 mm.

[0019] In some embodiments, the aforementioned preset pattern further includes a fourth region, and the second electrode layer also covers a portion of the fourth region. The fourth region is not connected to the first, second, or third regions. The fourth region can also be referred to as a cathode overlap region. The second electrode layer covers a portion of the fourth region, connecting the first and second electrodes corresponding to the fourth region to form a cathode overlap region.

[0020] After the organic electroluminescent device is packaged, a portion of the first region, a portion of the fourth region, and a portion of the third region are located outside the package structure, serving as three external electrodes of the organic electroluminescent device, through which the organic electroluminescent device is powered.

[0021] For example, the fourth region is located between the first region and the third region. The second electrode corresponds to the fourth region, and the first electrodes correspond to the first and third regions. The fourth region is positioned between the first and third regions to facilitate the connection between the first and second electrodes.

[0022] In some embodiments, the second and third regions can be located at any position, such as the middle or the edge of the first electrode layer, such that the second and third regions meet the following conditions: the first, second and third regions are not connected to each other, the second and third regions are connected through a sensing unit, and the area of ​​the first region is much larger than the area of ​​the second and third regions.

[0023] In one scenario, since the main function of the second light-emitting area corresponding to the second region is to demonstrate the bending degree of the organic electroluminescent device to the user, and the brightness of the second light-emitting area is relatively dimmer than that of the first light-emitting area during bending, the second and third regions can be placed at the edge of the first electrode layer to minimize the impact on the normal operation of the organic electroluminescent device. Moreover, the second and third regions should be much smaller than the first region.

[0024] Secondly, embodiments of this application provide a method for fabricating an organic electroluminescent device, comprising:

[0025] A first electrode layer with a preset pattern is formed on a substrate. The preset pattern includes a first region, a second region, and a third region that are not interconnected. The area of ​​the second region and the area of ​​the third region are both smaller than the area of ​​the first region.

[0026] A sensing unit is disposed on a substrate; wherein one end of the sensing unit is connected to the first electrode corresponding to the second region, and the other end is connected to the first electrode corresponding to the third region. Current is transmitted between the first electrode corresponding to the second region and the first electrode corresponding to the third region through the sensing unit, and the conductivity of the sensing unit changes when it is deformed.

[0027] An organic light-emitting layer is formed on the first electrode corresponding to the first region and the second region;

[0028] A second electrode layer is formed on the organic light-emitting layer.

[0029] In this embodiment, after the organic electroluminescent device is energized, the current can be transmitted through a first transmission path and a second transmission path. The first transmission path consists of a first electrode corresponding to a first region, an organic light-emitting layer corresponding to a second region, and a second electrode layer. The second transmission path consists of a first electrode corresponding to a third region, a sensing unit, a first electrode corresponding to a second region, and an organic light-emitting layer corresponding to a second region. Therefore, the organic light-emitting layer also has a first light-emitting region and a second light-emitting region. The first light-emitting region is the region of the organic light-emitting layer corresponding to the first region, and the second light-emitting region is the region of the organic light-emitting layer corresponding to the second region.

[0030] During the operation of an organic light-emitting device (OLED), if the OLED is bent, the sensing unit will deform accordingly, and the conductivity of the sensing unit will change. This causes the current in the first transmission path to differ from the current in the second transmission path, resulting in different light emission patterns in the first and second light-emitting regions. As the degree of bending of the OLED increases, the conductivity of the sensing unit changes with the deformation, further causing the light emission pattern of the second light-emitting region to change with the degree of bending. Therefore, the degree of bending of the OLED can be determined based on the light emission pattern of the second light-emitting region.

[0031] In some embodiments, the sensing unit includes multiple silicon nanowires, and setting the sensing unit on a predetermined area of ​​the substrate includes: setting multiple silicon nanowires on the substrate; and covering the multiple silicon nanowires with optical adhesive.

[0032] In some possible implementations, the above preparation method also includes curing the first electrode layer and the sensing unit together.

[0033] For example, if the material of the first electrode layer is PEDOT, the first electrode layer and the sensing unit are cured according to a first preset condition; wherein, the first preset condition is: 110℃~130℃, 30 minutes. If the material of the first electrode layer is CNT, or a composite material of AgNWs and resin, the first electrode layer and the sensing unit are cured according to a second preset condition; wherein, the second preset condition is: 90℃~110℃, 30 minutes.

[0034] In some possible implementations, the aforementioned preset pattern further includes a fourth region, and the second electrode layer also covers the first electrode corresponding to the fourth region. For example, the fourth region may be located between the first region and the third region.

[0035] Thirdly, embodiments of this application provide an electronic device including an organic electroluminescent device as described in any of the first aspects.

[0036] In some possible implementations, the electronic device may further include a control unit for sending control commands to a power supply unit that powers an organic electroluminescent device; the control commands instruct the power supply unit to supply power to a first electrode corresponding to a first region according to first power supply parameters, and to supply power to a first electrode corresponding to a third region according to second power supply parameters, wherein the first power supply parameters are different from the second power supply parameters.

[0037] In this embodiment, the first region and the third region can be powered according to different power supply parameters, making it easier for users to distinguish between the first light-emitting region and the second light-emitting region, thereby improving the effect of the second light-emitting region in showing the user the bending degree of the organic electroluminescent device.

[0038] In one scenario, the first power supply parameter may include a first voltage parameter and a first current parameter, and the second power supply parameter may include a second voltage parameter and a second current parameter. The first power supply parameter and the second power supply parameter may differ in that the first voltage parameter and the second voltage parameter are different, and / or, the first current parameter and the second current parameter are different.

[0039] For example, the initial brightness of the second light-emitting area is higher than that of the first light-emitting area. As the organic light-emitting device is bent, the resistance of the sensing unit gradually increases, causing the second light-emitting area to gradually dim. During the user's bending of the organic light-emitting device, the brightness of the second light-emitting area changes from higher than that of the first light-emitting area to much lower than that of the first light-emitting area. The user can easily distinguish between the first and second light-emitting areas, improving the demonstration of the bending degree of the organic light-emitting device and allowing the user to promptly detect the change in brightness of the second light-emitting area, thus preventing damage to the screen.

[0040] For example, if the initial brightness of the second light-emitting area is lower than that of the first light-emitting area, as the organic light-emitting device is bent, the resistance of the sensing unit gradually increases, causing the second light-emitting area to become increasingly dim. As the user bends the organic light-emitting device, the brightness of the second light-emitting area changes from being lower than that of the first light-emitting area to being significantly lower. This allows the user to easily distinguish between the first and second light-emitting areas, improving the demonstration of the bending degree of the organic light-emitting device and enabling the user to promptly detect the change in brightness of the second light-emitting area, thus preventing damage to the screen.

[0041] In another scenario, the first power supply parameter may include a current parameter with a first duty cycle, and the second power supply parameter may include a current parameter with a second duty cycle, wherein the first duty cycle is different from the second duty cycle.

[0042] For example, the first duty cycle can be the duty cycle corresponding to the one where the human eye cannot detect screen flicker, and the second duty cycle is smaller than the first duty cycle. After power is applied to the organic electroluminescent device, the first emitting area shows no flicker, while the second emitting area does flicker, and the user can easily distinguish between the first and second emitting areas. However, as the organic electroluminescent device is bent, the flicker in the second emitting area becomes increasingly difficult to observe until it disappears. The user can detect this phenomenon in time, thus avoiding damage to the screen. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a schematic diagram of the structure of the organic electroluminescent device provided in the embodiments of this application;

[0045] Figure 2 This is a schematic diagram of the light-emitting area provided in an embodiment of this application;

[0046] Figure 3 This is a schematic diagram of a first electrode layer and a sensing unit formed on a substrate, provided in an embodiment of this application;

[0047] Figure 4 This is another schematic diagram of the sensing unit provided in the embodiments of this application;

[0048] Figure 5 This is a schematic diagram of the formation of an organic light-emitting layer provided in an embodiment of this application;

[0049] Figure 6 This is yet another schematic diagram of the first electrode layer provided in the embodiments of this application;

[0050] Figure 7 This is another structural schematic diagram of the organic electroluminescent device provided in the embodiments of this application;

[0051] Figure 8 This is a schematic diagram of the structure of the packaged organic electroluminescent device provided in the embodiments of this application;

[0052] Figure 9 This is a schematic diagram of the external electrode of the organic electroluminescent device provided in the embodiments of this application;

[0053] Figure 10 This is a schematic flowchart of the method for fabricating an organic electroluminescent device provided in the embodiments of this application. Detailed Implementation

[0054] The present application will be described more clearly below with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the function of the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application. These all fall within the protection scope of the present application.

[0055] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0056] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0057] In the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0058] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0059] Furthermore, the term "multiple" mentioned in the embodiments of this application should be interpreted as two or more.

[0060] To make the objectives, technical solutions, and advantages of this application clearer, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.

[0061] Figure 1 A schematic diagram of the structure of the organic electroluminescent device provided in an embodiment of this application is shown. See also... Figure 1 The aforementioned organic electroluminescent device may include a substrate 100, a first electrode layer 200, a sensing unit 300, an organic light-emitting layer 400, and a second electrode layer 500.

[0062] A first electrode layer 200 is formed on the substrate 100 and has a preset pattern. The preset pattern includes a first region, a second region, and a third region that are not interconnected, and the areas of the second region and the third region are both smaller than the area of ​​the first region.

[0063] The sensing unit 300 is disposed on the substrate 100, with one end connected to the first electrode corresponding to the second region and the other end connected to the first electrode corresponding to the third region. Current can be transmitted between the first electrodes of the sensing unit 300 in the second and third regions, and the conductivity of the sensing unit 300 changes when it undergoes deformation.

[0064] An organic light-emitting layer 400 is formed on the first electrode corresponding to the first region and the second region. A second electrode layer 500 is formed on the organic light-emitting layer 400.

[0065] In this embodiment, after the organic electroluminescent device is energized, the current can be transmitted through a first transmission path and a second transmission path. The first transmission path consists of: a first electrode corresponding to the first region, an organic light-emitting layer corresponding to the second region, and a second electrode layer. The second transmission path consists of: a first electrode corresponding to the third region, a sensing unit, a first electrode corresponding to the second region, and an organic light-emitting layer corresponding to the second region and a second electrode layer. Therefore, the organic light-emitting layer 400 also has the following characteristics: Figure 2 The first luminescent region and the second luminescent region are shown. The first luminescent region is the region of the organic light-emitting layer 400 corresponding to the first region, and the second luminescent region is the region of the organic light-emitting layer 400 corresponding to the second region.

[0066] During the operation of an organic electroluminescent device (OLED), if the OLED is bent, the sensing unit 300 will deform accordingly, causing a change in the conductivity of the sensing unit 300. This results in a difference between the current in the first transmission path and the current in the second transmission path, leading to a difference in the luminescence of the first and second luminous regions. As the degree of bending of the OLED increases, the conductivity of the sensing unit 300 changes with the deformation, causing the luminescence of the second luminous region to change with the degree of bending. Therefore, the degree of bending of the OLED can be determined based on the luminescence of the second luminous region, preventing damage to the OLED.

[0067] See Figure 3 The first electrode layer 200 includes a first region, a second region, and a third region. The first region, the second region, and the third region are not interconnected, but the second region and the third region are electrically connected through a sensing unit 300. After energizing the first electrode corresponding to the third region, current is transmitted through the sensing unit 300 between the first electrode corresponding to the third region and the first electrode corresponding to the second region.

[0068] In some embodiments, the sensing unit 300 may include multiple silicon nanowires arranged between the second and third regions. Optical adhesive is applied to the silicon nanowires, which secures them to the substrate 100 and prevents them from contacting the second electrode layer 500. In this embodiment, the silicon nanowires may be single-crystal silicon nanowires.

[0069] The longer the silicon nanowire, the more accurate the assessment of the bending degree of organic electroluminescent devices. For example... Figure 4 As shown, when the length of the silicon nanowire is close to the single-side dimension of the organic light-emitting layer, the deformation of the silicon nanowire is more timely and accurate when the organic electroluminescent device is bent.

[0070] It should be noted that silicon nanowires are one implementation of the sensing unit 300, and the embodiments of this application are not limited to this. The sensing unit 300 can satisfy the following: when the organic electroluminescent device is bent, the sensing unit 300 deforms, causing its conductivity to change, and it can be applied in organic electroluminescent devices.

[0071] In some embodiments, the substrate 100 and the first electrode layer are both rectangular, and the second and third regions may be located at the edge of one side of the first electrode layer 200. For example... Figure 3 As shown, the second region and the third region are located on the right edge of the first electrode layer 200, and the third region is close to the lower edge of the first electrode layer 200. The area of ​​the first region is much larger than the area of ​​the second region and the area of ​​the third region.

[0072] In this embodiment, since the main function of the second light-emitting area corresponding to the second region is to show the user the degree of bending of the organic electroluminescent device, and the brightness of the second light-emitting area is relatively darker than that of the first light-emitting area during the bending process, the second region and the third region can be set at the edge of the first electrode layer 200 to minimize the impact on the normal operation of the organic electroluminescent device.

[0073] In some embodiments, the second and third regions may be located in the middle of the first electrode layer 200. For example, [the following is an example of a different embodiment]. Figure 3 The positions of the second region, the third region, and the sensing unit 300 shown in the figure are moved to the left to the middle of the first electrode layer 200, and the second region, the third region, and the sensing unit 300 are embedded in the first region.

[0074] It should be noted that the layout of the first, second, and third regions in the figure is merely illustrative and is not intended to limit the scope of this application. The layout of the first, second, and third regions should satisfy the following: the first, second, and third regions are not interconnected; the second and third regions are connected through the sensing unit 300; and the area of ​​the first region is significantly larger than the areas of the second and third regions.

[0075] Furthermore, the specific shape of each region is not limited in this embodiment. In this embodiment, the first electrode layer 200 is rectangular overall, the first region is a relatively regular polygon, and the second and third regions are rectangular. This is merely an illustrative example and is not intended to be limiting. In other embodiments, the first electrode layer 200 can be set to a shape other than a rectangle according to actual needs, and the first, second, and third regions can all be set to shapes other than those shown in the figure.

[0076] See Figure 5 The organic light-emitting layer 400 is formed on the first and second regions, forming a structure as shown in the figure. Figure 2The first luminescent region and the second luminescent region are shown. The organic light-emitting layer 400 does not cover the lower portion of the first region, and the first luminescent region is the region of the organic light-emitting layer 400 corresponding to the first region, while the second luminescent region is the region of the organic light-emitting layer 400 corresponding to the second region.

[0077] For example, the shape of the first light-emitting region can be the same as the shape of the first region, and the shape of the second light-emitting region can be the same as the shape of the second region. Moreover, in the portion corresponding to the second electrode layer 500, the first light-emitting region can be slightly larger than the first region, and the second light-emitting region can be slightly larger than the second region. Thus, when forming the second electrode layer 500, it is possible to better prevent the first electrode layer 200 from contacting the second electrode layer 500 and causing a short circuit.

[0078] Furthermore, to ensure the second luminous area can be lit normally, the area of ​​the second luminous area and the current of the second transmission path can be determined according to the formula B*S=I*η, where B is the brightness, S is the area, I is the current, and η is the current efficiency. If the current of the organic electroluminescent device is I1 and the luminous area is S1, then the relationship between the luminous area S2 of the second luminous area and the current I2 is S2 / I2=S1 / I1. That is, when the luminous area S2 of the second luminous area and the current I2 satisfy the relationship S2 / I2=S1 / I1, the brightness of the second luminous area is the same as that of the first luminous area. Therefore, the current flowing through the sensing unit 300 can be set so that the brightness of the second luminous area is higher than, lower than, or equal to the brightness of the first luminous area, thus providing a theoretical current value for the design of the sensing unit 300.

[0079] like Figure 1 As shown, the second electrode layer 500 is formed on the organic light-emitting layer 400 and covers the entire organic light-emitting layer 400 and the sensing unit 300. The second electrode layer 500 can provide a certain degree of fixation for the sensing unit 300. The pattern of the second electrode layer 500 is different from that of the first region; it can be a rectangle, covering the regions corresponding to the first region, the second region, and the sensing unit 300, and the second electrode layer 500 does not contact the first electrode corresponding to the third region.

[0080] The working process of the above-mentioned organic electroluminescent device will be explained below, taking the first electrode as the anode and the second electrode as the cathode as an example.

[0081] After a voltage is applied to the second electrode layer 500 and the first electrode corresponding to the second region, current flows from the second electrode layer 500 to the first electrode corresponding to the second region. After a voltage is applied to the second electrode layer 500 and the first electrode corresponding to the first region, current flows from the second electrode layer 500 to the first electrode corresponding to the first region.

[0082] This yields a first transmission path and a second transmission path for current transport. The first transmission path consists of: a second electrode layer 500, an organic light-emitting layer 400 corresponding to the first light-emitting region, and a first electrode corresponding to the first region. The second transmission path consists of: a second electrode layer 500, an organic light-emitting layer 400 corresponding to the second light-emitting region, a first electrode corresponding to the third region, a silicon nanowire, and a first electrode corresponding to the third region.

[0083] During the operation of an organic light-emitting device (OLED), if the device is bent, each silicon nanowire will deform and elongate accordingly. This changes the conductivity of the silicon nanowire, increasing its resistance. Consequently, the current in the second transmission path decreases, while the current in the first transmission path remains essentially unchanged. The decrease in current in the second transmission path leads to a dimming of the light emission brightness in the second emitting region, while the brightness of the first emitting region remains essentially unchanged.

[0084] When the resistance of silicon nanowires is too high, the second luminescent region becomes severely darkened. Further bending of the organic light-emitting device (OLED) may cause it to crack or break. In this embodiment, a bending test was performed on an OLED with a 0.15mm thin glass substrate to obtain the relationship between the degree of bending and the luminous brightness of the second luminescent region, as shown in the table below.

[0085] Bending degree (unit: degree) 0° 15° 30° 45° 60° 75° 90° Luminous brightness (unit: nit) 1000 800 600 400 200 100 50

[0086] The data in the table above shows an inverse correlation between the bending angle of the organic electroluminescent device and the brightness of the second luminous region: the larger the bending angle, the dimmer the brightness of the second luminous region; conversely, the smaller the bending angle, the brighter the brightness. When the bending angle reaches 90°, the brightness of the second luminous region is at its lowest. Further bending at this point will cause the organic electroluminescent device to crack or break.

[0087] See Figure 6 and Figure 7 The preset pattern of the first electrode layer 200 may also include a fourth region, and the second electrode layer 500 further covers a portion of the fourth region. The fourth region is not connected to the first, second, or third regions. The fourth region can also be referred to as the cathode overlap region. The second electrode layer 500 covers the first electrode corresponding to a portion of the fourth region, connecting the first electrode to the second electrode to form the cathode overlap region.

[0088] like Figure 8 and Figure 9As shown, after the organic electroluminescent device is packaged, a portion of the first region, a portion of the fourth region, and a portion of the third region are located outside the packaging structure 600, serving as three external electrodes of the organic electroluminescent device, namely the first external electrode, the second external electrode, and the third external electrode, which supply power to the organic electroluminescent device.

[0089] Taking the first electrode as the anode and the second electrode as the cathode as an example, in Figure 8 and Figure 9 In the diagram, the first external electrode (i.e., the external electrode on the left) is the anode, the second external electrode (i.e., the external electrode in the middle) is the cathode, and the third external electrode (i.e., the external electrode on the right) is the anode.

[0090] like Figure 6 As shown, the fourth region can be located between the first and third regions. The fourth region corresponds to the second electrode, and the first and third regions correspond to the first electrodes. Placing the fourth region between the first and third regions facilitates the connection between the first and second electrodes.

[0091] It should be noted that the fourth region being located between the first and third regions is merely an illustrative example. In other embodiments of this application, the fourth region may not be located between the first and third regions, and this application does not limit this aspect.

[0092] Figure 10 A schematic flowchart illustrating the fabrication method of the organic electroluminescent device provided in this application embodiment is shown. See also... Figure 10 The preparation method of the above-mentioned organic electroluminescent devices is described in detail below:

[0093] Step 1001: Form a first electrode layer with a preset pattern on the substrate.

[0094] The aforementioned preset pattern includes a first region, a second region, and a third region that are not interconnected. The areas of the second and third regions are both smaller than the area of ​​the first region. For details regarding the first, second, and third regions, please refer to the aforementioned embodiments of the organic electroluminescent device; they will not be repeated here.

[0095] In some embodiments, a first electrode layer having the aforementioned preset pattern can be formed on a substrate using screen printing.

[0096] Step 1002: Set the sensing unit on the substrate.

[0097] In this sensor unit, one end is connected to the first electrode corresponding to the second region, and the other end is connected to the first electrode corresponding to the third region. Current is transmitted between the first electrodes of the second and third regions through the sensor unit, and the conductivity of the sensor unit changes when it deforms.

[0098] In some embodiments, the sensing unit may include multiple silicon nanowires, and setting the sensing unit on a predetermined area of ​​the substrate includes: setting multiple silicon nanowires on the substrate; and covering the multiple silicon nanowires with optical adhesive.

[0099] For example, silicon nanowires can be fabricated and then arranged between a second region and a first region. For instance, tweezers or automated equipment can be used to arrange the silicon nanowires on a substrate between the second and first regions.

[0100] One method for preparing silicon nanowires is temperature gradient assisted growth, which can produce nanowires up to 2 cm in length. Of course, other feasible methods can also be used to prepare silicon nanowires, and the length of the nanowires is not limited.

[0101] The longer the silicon nanowire, the more accurate the assessment of the bending degree of the organic electroluminescent device. When the length of the silicon nanowire is close to the single-side dimension of the organic light-emitting layer, the deformation of the silicon nanowire is timely and more accurate when the organic electroluminescent device is bent.

[0102] In the embodiments of this application, step 1001 can be performed first and then step 1002, or step 1002 can be performed first and then step 1001, or steps 1001 and 1002 can be performed simultaneously. There is no limitation on this. As long as the first electrode layer and the sensing unit are formed on the substrate, and the two ends of the sensing unit are respectively connected to the first electrode corresponding to the second region and the first electrode corresponding to the third region.

[0103] In some possible implementations, after steps 1001 and 1002, the above preparation method may further include: curing the first electrode layer and the sensing unit together.

[0104] For example, after forming a first electrode layer on a substrate, a sensing unit is placed on the substrate before the first electrode layer has cured. Then, the first electrode layer and the sensing unit are cured together.

[0105] If the first electrode layer is made of PEDOT, the first electrode layer and the sensing unit are cured according to the first preset conditions; wherein the first preset conditions are: 110℃~130℃, 30 minutes. If the first electrode layer is made of CNT, or a composite material of AgNWs and resin, the first electrode layer and the sensing unit are cured according to the second preset conditions; wherein the second preset conditions are: 90℃~110℃, 30 minutes.

[0106] In some other possible implementations, after step 1001, the above preparation method may further include: curing the first electrode layer. Then, step 1002 is performed to further cure the sensing unit.

[0107] In some other possible implementations, after step 1002, the above preparation method may further include: curing the sensing unit. Then, step 1001 is performed to further cure the first electrode layer.

[0108] Step 1003: An organic light-emitting layer is formed on the first electrode corresponding to the first region and the second region.

[0109] For example, an organic light-emitting layer can be obtained by vapor deposition of an organic material on the first electrode corresponding to the first region and the second region. The organic light-emitting layer does not cover the lower portion of the first region, such as... Figure 4 As shown.

[0110] The shape of the first light-emitting region can be the same as the shape of the first region, and the shape of the second light-emitting region can be the same as the shape of the second region. Moreover, in the portion corresponding to the second electrode layer, the first light-emitting region can be slightly larger than the first region, and the second light-emitting region can be slightly larger than the second region. Therefore, when forming the second electrode layer, it is possible to better prevent the first electrode layer from contacting the second electrode layer and causing a short circuit.

[0111] Alternatively, the current flowing through the sensing unit can be set according to the formula B*S=I*η, such that the brightness of the second emitting region is higher than, lower than, or equal to the brightness of the first emitting region, where B is the brightness, S is the area, I is the current, and η is the current efficiency. If the current of the organic electroluminescent device is I1 and the emitting area is S1, then the relationship between the emitting area S2 of the second emitting region and the current I2 is S2 / I2=S1 / I1. That is, when the emitting area S2 of the second emitting region and the current I2 satisfy the relationship S2 / I2=S1 / I1, the brightness of the second emitting region is the same as the brightness of the first emitting region.

[0112] Step 1004: Form a second electrode layer on the organic light-emitting layer.

[0113] In this step, a second electrode layer can be deposited on the organic light-emitting layer. For example... Figure 1As shown, the second electrode layer can cover the entire organic light-emitting layer and the sensing unit. The second electrode layer can provide a certain degree of fixation for the sensing unit. The pattern of the second electrode layer differs from that of the first region; it can be a rectangle covering the areas corresponding to the first region, the second region, and the sensing unit, and the second electrode layer does not contact the first electrode corresponding to the third region.

[0114] Optionally, after step 1004, the above-mentioned method for fabricating the organic electroluminescent device may further include: encapsulating the organic electroluminescent device after the formation of the second electrode layer. For example... Figure 8 and Figure 9 As shown, a portion of the first region, a portion of the fourth region, and a portion of the third region are located outside the encapsulation structure, serving as three external electrodes for the organic electroluminescent device, through which the organic electroluminescent device is powered.

[0115] For example, an organic electroluminescent device after the formation of the second electrode layer can be encapsulated using aluminum foil.

[0116] In this embodiment, after the organic electroluminescent device is energized, the current can be transmitted through a first transmission path and a second transmission path. The first transmission path consists of a first electrode corresponding to a first region, an organic light-emitting layer corresponding to a second region, and a second electrode layer. The second transmission path consists of a first electrode corresponding to a third region, a sensing unit, a first electrode corresponding to a second region, and an organic light-emitting layer corresponding to a second region. Therefore, the organic light-emitting layer also has a first light-emitting region and a second light-emitting region. The first light-emitting region is the region of the organic light-emitting layer corresponding to the first region, and the second light-emitting region is the region of the organic light-emitting layer corresponding to the second region.

[0117] During the operation of an organic light-emitting device (OLED), if the OLED is bent, the sensing unit will deform accordingly, and the conductivity of the sensing unit will change. This causes the current in the first transmission path to differ from the current in the second transmission path, resulting in different light emission patterns in the first and second light-emitting regions. As the degree of bending of the OLED increases, the conductivity of the sensing unit changes with the deformation, further causing the light emission pattern of the second light-emitting region to change with the degree of bending. Therefore, the degree of bending of the OLED can be determined based on the light emission pattern of the second light-emitting region.

[0118] This application also provides an electronic device, including the above-mentioned organic electroluminescent device, which has the advantages of the above-mentioned organic electroluminescent device, and will not be repeated here.

[0119] For example, the above-mentioned electronic devices can be wearable devices, mobile phones, tablets, personal digital assistants (PDAs), portable devices (e.g., portable computers) and other devices with foldable display screens. The specific type of electronic device is not limited in the embodiments of this application.

[0120] In some embodiments, the electronic device may further include a control unit for sending control commands to a power supply unit that powers the organic electroluminescent device. The control commands instruct the power supply unit to supply power to the first electrode corresponding to the first region according to first power supply parameters, and to supply power to the first electrode corresponding to the third region according to second power supply parameters, wherein the first and second power supply parameters are different.

[0121] In this embodiment, the first region and the third region can be powered according to different power supply parameters, making it easier for users to distinguish between the first light-emitting region and the second light-emitting region, thereby improving the effect of the second light-emitting region in showing the user the bending degree of the organic electroluminescent device.

[0122] In one scenario, the first power supply parameter may include a first voltage parameter and a first current parameter, and the second power supply parameter may include a second voltage parameter and a second current parameter. The first power supply parameter and the second power supply parameter may differ in that the first voltage parameter and the second voltage parameter are different, and / or, the first current parameter and the second current parameter are different.

[0123] For example, the initial brightness of the second light-emitting area is higher than that of the first light-emitting area. As the organic light-emitting device is bent, the resistance of the sensing unit gradually increases, causing the second light-emitting area to gradually dim. During the user's bending of the organic light-emitting device, the brightness of the second light-emitting area changes from higher than that of the first light-emitting area to much lower than that of the first light-emitting area. The user can easily distinguish between the first and second light-emitting areas, improving the demonstration of the bending degree of the organic light-emitting device and allowing the user to promptly detect the change in brightness of the second light-emitting area, thus preventing damage to the screen.

[0124] For example, if the initial brightness of the second light-emitting area is lower than that of the first light-emitting area, as the organic light-emitting device is bent, the resistance of the sensing unit gradually increases, causing the second light-emitting area to become increasingly dim. As the user bends the organic light-emitting device, the brightness of the second light-emitting area changes from being lower than that of the first light-emitting area to being significantly lower. This allows the user to easily distinguish between the first and second light-emitting areas, improving the demonstration of the bending degree of the organic light-emitting device and enabling the user to promptly detect the change in brightness of the second light-emitting area, thus preventing damage to the screen.

[0125] In another scenario, the first power supply parameter may include a current parameter with a first duty cycle, and the second power supply parameter may include a current parameter with a second duty cycle, wherein the first duty cycle is different from the second duty cycle.

[0126] For example, when an organic electroluminescent device is designed to be used as a screen for a bent electronic product, PWM (Pulse Width Modulation) technology can be used to control the flashing of a second light-emitting area to alert the user to the degree of bending of the screen.

[0127] Specifically, different duty cycles of current square waves can be delivered to the first electrode corresponding to the first region and the first electrode corresponding to the third region via the chip of the electronic device. For example, a current square wave with a first duty cycle can be delivered to the first electrode corresponding to the first region, and a current square wave with a second duty cycle can be delivered to the first electrode corresponding to the third region. The first duty cycle can be the duty cycle that the human eye cannot detect screen flickering, and the second duty cycle is smaller than the first duty cycle.

[0128] When the screen of an electronic product is powered on, the first luminous area shows no flicker, while the second luminous area flickers. Users can easily distinguish between the two areas. However, as the screen is bent, the resistance of the sensing unit increases, the current flowing through the second luminous area decreases, and the flickering becomes increasingly difficult to observe until it disappears. Therefore, users can promptly detect the disappearance of the flickering, thus preventing damage to the screen.

[0129] Optionally, the aforementioned electronic device can also collect the current flowing through the third external electrode. When this current is less than a current threshold, the electronic device can generate a screen bending warning message to better remind the user to prevent the screen from being broken. This current threshold can be determined based on experimental data, and different electronic devices and different screens may have different current thresholds.

[0130] Optionally, the aforementioned electronic device can also collect the current flowing through the third external electrode. When the variation range of this current exceeds a preset variation threshold, the electronic device can generate a screen bending warning message to better remind the user to prevent the screen from being broken. The preset variation threshold can be determined based on experimental data, and different electronic devices and different screens may have different preset variation thresholds.

[0131] For example, the aforementioned screen bending warning information can be implemented in at least one of the following ways: emitting a specific sound, displaying text / images in the second luminous area, and the second luminous area flashing.

[0132] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0133] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An organic electroluminescent device, characterized in that, include: Base; A first electrode layer having a preset pattern is formed on the substrate; wherein the preset pattern includes a first region, a second region, and a third region that are not interconnected, and the areas of the second region and the third region are both smaller than the area of ​​the first region; A sensing unit is disposed on the substrate, with one end connected to a first electrode corresponding to the second region and the other end connected to a first electrode corresponding to the third region; wherein current is transmitted through the sensing unit between the first electrode corresponding to the second region and the first electrode corresponding to the third region, and the conductivity of the sensing unit changes when deformation occurs; the sensing unit includes silicon nanowires. An organic light-emitting layer is formed on the first electrode corresponding to the first region and the second region; A second electrode layer is formed on the organic light-emitting layer; The organic light-emitting layer includes a first light-emitting region and a second light-emitting region, wherein the first light-emitting region is the region of the organic light-emitting layer corresponding to the first region, and the second light-emitting region is the region of the organic light-emitting layer corresponding to the second region; The luminescence of the second luminescent region can vary with the degree of bending of the organic electroluminescent device.

2. The organic electroluminescent device according to claim 1, characterized in that, Multiple silicon nanowires are disposed between the second region and the third region, and the first electrode corresponding to the second region and the first electrode corresponding to the third region are electrically connected through the multiple silicon nanowires.

3. The organic electroluminescent device according to claim 2, characterized in that, The multiple silicon nanowires are coated with optical adhesive.

4. The organic electroluminescent device according to claim 1, characterized in that, The first electrode layer is made of PEDOT or CNT, and / or the substrate is a glass substrate with a thickness less than a threshold.

5. The organic electroluminescent device according to claim 1, characterized in that, The preset pattern also includes a fourth region, and the second electrode layer further covers the fourth region.

6. The organic electroluminescent device according to claim 1, characterized in that, The second region and the third region are located in the middle or at the edge of the substrate.

7. A method for fabricating an organic electroluminescent device, characterized in that, include: A first electrode layer with a preset pattern is formed on a substrate. The preset pattern includes a first region, a second region, and a third region that are not interconnected. The area of ​​the second region and the area of ​​the third region are both smaller than the area of ​​the first region. A sensing unit is disposed on a substrate, one end of which is connected to a first electrode corresponding to the second region, and the other end of which is connected to a first electrode corresponding to the third region; wherein, current is transmitted through the sensing unit between the first electrode corresponding to the second region and the first electrode corresponding to the third region, and the conductivity of the sensing unit changes when deformation occurs; the sensing unit includes silicon nanowires. An organic light-emitting layer is formed on the first electrode corresponding to the first region and the second region; A second electrode layer is formed on the organic light-emitting layer; The organic light-emitting layer includes a first light-emitting region and a second light-emitting region, wherein the first light-emitting region is the region of the organic light-emitting layer corresponding to the first region, and the second light-emitting region is the region of the organic light-emitting layer corresponding to the second region; The luminescence of the second luminescent region can vary with the degree of bending of the organic electroluminescent device.

8. The method for preparing the organic electroluminescent device according to claim 7, characterized in that, The step of setting the sensing unit on a preset area of ​​the substrate includes: Multiple silicon nanowires are disposed on a predetermined region of the substrate; Optical adhesive is coated onto the multiple silicon nanowires.

9. The method for preparing the organic electroluminescent device according to claim 7, characterized in that, The preparation method further includes: The first electrode layer and the sensing unit are cured together.

10. The method for preparing the organic electroluminescent device according to claim 9, characterized in that, If the material of the first electrode layer is PEDOT, then the first electrode layer and the sensing unit are cured according to the first preset conditions; wherein, the first preset conditions are: 110℃~130℃, 30 minutes; If the material of the first electrode layer is CNT, or a composite material of AgNWs and resin, then the first electrode layer and the sensing unit are cured according to the second preset conditions; wherein, the second preset conditions are: 90℃~110℃, 30 minutes.

11. The method for fabricating an organic electroluminescent device according to claim 8, characterized in that, The preset pattern also includes a fourth region, and the second electrode layer further covers the first electrode corresponding to the fourth region.

12. An electronic device, characterized in that, Including the organic electroluminescent device as described in any one of claims 1 to 6.

13. The electronic device according to claim 12, characterized in that, The electronic device further includes a control unit, which is used to send control commands to the power supply unit that powers the organic electroluminescent device; The control command is used to instruct the power supply unit to supply power to the first electrode corresponding to the first region according to the first power supply parameters, and to supply power to the first electrode corresponding to the third region according to the second power supply parameters, wherein the first power supply parameters are different from the second power supply parameters.

14. The electronic device according to claim 13, characterized in that, The first power supply parameter includes a first voltage parameter and a first current parameter, and the second power supply parameter includes a second voltage parameter and a second current parameter; The first power supply parameter differs from the second power supply parameter in that: the first voltage parameter differs from the second voltage parameter, and / or the first current parameter differs from the second current parameter.

15. The electronic device according to claim 13, characterized in that, The first power supply parameter includes a current parameter with a first duty cycle, and the second power supply parameter includes a current parameter with a second duty cycle, wherein the first duty cycle and the second duty cycle are different.

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