An OLED test structure and its preparation method, test device, and test method

Abstract

The present application discloses an OLED test structure and a preparation method, a test device, and a test method thereof, including a test area, wherein the test area includes: a plurality of sub-pixels, wherein the plurality of sub-pixels form a plurality of pixel columns arranged in an array, and the sub-pixels in each pixel column are arranged in parallel; a first test terminal, wherein the first test terminal includes an electrode ring, wherein the electrode ring is arranged around the test area, and the electrode ring is a semi-closed structure; and further includes a second test terminal or a third test terminal, wherein the second test terminal is connected to each of the pixel columns; the third test terminal includes an odd column connection terminal and an even column connection terminal, wherein the odd column connection terminal is connected to the odd pixel column, and the even column connection terminal is connected to the even pixel column.

Description

Technical Field

[0001] The present application generally relates to the field of display technology, and specifically relates to an OLED test structure and a preparation method, a test device, and a test method thereof. Background Art

[0002] OLED (Organic Light-Emitting Diode) displays, due to their thinness, vibrant colors, and flexibility, have become the preferred choice for high-end mobile phones, televisions, watches, and other electronic devices. However, with the development of OLED technology, the demand for display quality is also becoming increasingly stringent. OLED display devices have many performance specifications, including power consumption, brightness, and color coordinates, with color shift being a key parameter.

[0003] To cause a given pixel in an OLED display to emit light, a voltage is applied to the anode of that pixel. Ideally, the anode of that pixel would not affect any adjacent pixels. However, the conductivity of the OLED layer at the anode allows lateral conduction from the anode of a given pixel to the anode of an adjacent pixel. This can cause pixel crosstalk, where adjacent pixels emit light due to leakage current from the given pixel. Pixel crosstalk can cause color shift, affecting the display.

[0004] However, existing leakage tests generally measure the brightness of the display panel to approximately reflect the leakage of the display panel, making it impossible to evaluate the leakage level of a single pixel. Testing the leakage level can also provide a reference for subsequent OLED design and process preparation. Summary of the Invention

[0005] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide an OLED test structure and a preparation method thereof, a test device, and a test method, which can test the leakage condition in the display panel.

[0006] In a first aspect, the present application provides an OLED test structure, comprising a test area, wherein the test area includes:

[0007] A plurality of sub-pixels, wherein the plurality of sub-pixels form a plurality of pixel columns arranged in an array, and the sub-pixels in each pixel column are arranged in parallel;

[0008] a first test terminal, wherein the first test terminal includes an electrode ring, the electrode ring is arranged around the test area, and the electrode ring has a semi-enclosed structure;

[0009] Also includes a second test terminal or a third test terminal, wherein,

[0010] The second test terminal is connected to each of the pixel columns;

[0011] The third test terminals include odd column connection terminals and even column connection terminals. The odd column connection terminals are connected to odd pixel columns, and the even column connection terminals are connected to even pixel columns.

[0012] Optionally, the sub-pixel includes a light-emitting element and an anode and a cathode located on both sides of the light-emitting element, the cathode of the light-emitting element is connected to the first test terminal, and the anode of the light-emitting element is connected to the second test terminal or the third test terminal.

[0013] Optionally, the test area includes a first test area, and the second test terminal and the first test terminal are provided on the first test area; the first test terminal and the second test terminal are provided on the same layer in the first test area.

[0014] Optionally, the first test terminal surrounds the first test area, a first cathode pad is provided on the first test terminal, and an anode pad is provided on the second test terminal.

[0015] Optionally, the electrode ring surrounds three sides of the four sides of the first test area, and the cathode pad and the anode pad are located on another side of the four sides of the test area.

[0016] Optionally, the second test terminal further includes a plurality of first connection lines connected to the anode pad, and each first connection line is connected to one of the pixel columns.

[0017] Optionally, the test area includes a second test area, the third test terminal and the first test terminal are provided on the second test area, and the first test terminal and the third test terminal are provided on the same layer in the second test area.

[0018] Optionally, the first test terminal surrounds the second test area, a second cathode pad is provided on the first test area, and the third test terminal includes an odd-numbered column pad and an even-numbered column pad.

[0019] Optionally, the electrode ring surrounds three of the four sides of the second test area, one of the odd-numbered column pads and the even-numbered column pads is located on another of the four sides of the test area, and the other of the odd-numbered column pads and the even-numbered column pads is located on the same side as the cathode pad.

[0020] Optionally, the third test terminal also includes a plurality of second connection lines connected to the odd column pads, and one of the second connection lines is connected to an odd pixel column respectively. The third test terminal also includes a plurality of third connection lines connected to the even column pads, and one of the third connection lines is connected to an even pixel column.

[0021] In a second aspect, the present application provides a method for preparing an OLED test structure, for preparing any of the above-described OLED test structures, the method comprising:

[0022] providing a substrate;

[0023] forming a first anode layer on the base substrate and patterning the anode layer to form a sub-pixel;

[0024] forming a second anode layer on the base substrate, and patterning the first test terminal and one of the second test terminal and the third test terminal;

[0025] forming a pixel defining layer on the second anode layer, and patterning the layer to form a sub-pixel region and a via region;

[0026] A light emitting element, a cathode and a via hole of the sub-pixel are formed on the pixel defining layer.

[0027] In a third aspect, the present application provides an OLED testing device, which adopts any of the above-described test structures and includes a first test unit or a second test unit, wherein:

[0028] The first test unit includes a first signal sending module and a first signal detection module, the first signal sending module is used to send a test signal to the first detection terminal and the second detection terminal; the first signal detection module is used to detect the current on the second detection terminal;

[0029] The second test unit includes a second signal sending module and a second signal detection module. The second signal sending module is used to send a test signal to the first detection terminal and the third detection terminal; the second signal detection module is used to detect the current on the third detection terminal.

[0030] In a fourth aspect, the present application provides an OLED testing method, using the OLED testing device as described above, the method comprising performing one or more of the following:

[0031] inputting a cathode potential through the first test terminal and an anode potential through the second test terminal to obtain a first current value on the second test terminal;

[0032] inputting a cathode potential through the first test terminal, inputting an anode potential through the odd-numbered connection terminals in the third test terminal, and inputting a zero potential through the even-numbered connection terminals, to obtain a second current value on the even-numbered connection terminals;

[0033] inputting a cathode potential through the first test terminal, inputting an anode potential through the even-numbered connection terminals in the third test terminal, and inputting a zero potential through the odd-numbered connection terminals, to obtain a third current value on the odd-numbered connection terminals;

[0034] A cathode potential is input through the first test terminal, and the same anode potential is input through the odd-numbered column connection terminal and the even-numbered column connection terminal in the third test terminal to obtain a fourth current value on the odd-numbered column connection terminal, or to obtain a fifth current value on the even-numbered column connection terminal.

[0035] Optionally, the leakage level of the test area is characterized by at least one of the following:

[0036] The first leakage level of the test area is equal to the first current value / the total number of sub-pixels in the test area;

[0037] The second leakage level of the test area is equal to the second current value / the total number of sub-pixels in the even-numbered pixel columns in the test area;

[0038] The second leakage level of the test area is equal to the third current value / the total number of sub-pixels in the odd-numbered pixel columns in the test area;

[0039] The first leakage level of the test area is equal to the fourth current value / the total number of sub-pixels in the test area;

[0040] The first leakage level of the test area is equal to the fifth current value / the total number of sub-pixels in the test area.

[0041] The technical solutions provided by the embodiments of the present application may have the following beneficial effects:

[0042] The OLED test structure provided in the embodiment of the present application is simple to prepare by being arranged on the anode layer of the display panel, and can realize the test of the leakage situation of the OLED. When used, various test structures can be arranged according to the test requirements to realize the test of different leakage levels; it is convenient to provide a reference for subsequent OLED design and process preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0044] Figure 1 This is a schematic structural diagram of an OLED display panel in the prior art;

[0045] Figure 2 A schematic structural diagram of an OLED test structure provided in an embodiment of the present application;

[0046] Figure 3 A schematic structural diagram of another OLED test structure provided in an embodiment of the present application;

[0047] Figure 4 A flow chart of a method for preparing an OLED test structure provided in Example 1 of the present application;

[0048] Figure 5 for Figure 2 Schematic diagram of the cross section at AA in the middle;

[0049] Figure 6 A schematic structural diagram of an OLED testing device provided in Example 1 of the present application;

[0050] Figure 7 A flow chart of an OLED testing method provided in Example 1 of the present application;

[0051] Figure 8 A flow chart of a method for preparing an OLED test structure provided in Example 2 of the present application;

[0052] Figure 9 for Figure 3 Schematic diagram of the cross section at the middle BB;

[0053] Figure 10 A schematic structural diagram of an OLED testing device provided in Example 2 of the present application;

[0054] Figure 11 A flow chart of an OLED testing method provided in Example 2 of the present application; DETAILED DESCRIPTION

[0055] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0056] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0057] When the OLED needs to emit light, an electrical signal is supplied to the anode 100 and cathode 200 of the OLED. Due to the voltage difference between the anode 100 and cathode 200, holes generated by the anode 100 are injected into the luminescent layer 300, and electrons generated by the cathode 200 are also injected into the luminescent layer 300. The electrons and holes recombine in the luminescent layer 300 to generate excitons, which then radiatively transition from an excited state to a ground state, causing the luminescent layer 300 to emit light of the corresponding color. When the OLED does not need to emit light, the voltage difference between the anode 100 and cathode 200 of the OLED is zero. Carriers, including electrons and holes, do not move from the anode 100 and cathode 200 to the luminescent layer 300. Consequently, no excitons are generated in the luminescent layer 300, and the luminescent layer 300 does not emit light.

[0058] At present, in order to improve the migration and recombination efficiency of carriers, such as Figure 1 As shown, a hole injection layer 301 (Hole Inject Layer; HIL) and a hole transport layer 302 (Hole Transport Layer; HTL) are usually set between the anode 100 and the light-emitting layer 300, and an electron injection layer 303 (Electron Inject Layer; EIL) and an electron transport layer 304 (Electron Transport Layer; ETL) are set between the cathode 200 and the light-emitting layer 300.

[0059] However, since the functional layers including the hole injection layer HIL 301, the hole transport layer HTL 302, the electron injection layer EIL 303, and the electron transport layer ETL 304 are generally planar structures covering each organic light-emitting device, if, at a certain moment, a certain sub-pixel needs to be in an emitting state and the second organic light-emitting device needs to be in a non-emitting state, then at that moment, the anode 100 and cathode 200 included in the certain sub-pixel receive an electrical signal, while the anode 100 and cathode 200 included in the adjacent sub-pixel do not receive an electrical signal. Carriers pass through the hole injection layer HIL 301, the hole transport layer HTL 302, the electron injection layer 303 EIL, and the electron transport layer ETL 304 corresponding to the certain sub-pixel and migrate to the light-emitting layer 300 included in the certain sub-pixel.

[0060] However, since the common film layers such as the hole injection layer 301, the hole transport layer 302, the electron injection layer 303 and the electron transport layer 304 between a certain sub-pixel and an adjacent sub-pixel are interconnected, carriers will migrate from a certain sub-pixel to an adjacent sub-pixel through the above-mentioned common film layers, causing an adjacent sub-pixel that should not emit light to emit light, that is, causing a problem of mutual crosstalk between a certain sub-pixel and an adjacent sub-pixel.

[0061] Because the subpixels on the display panel are arranged in an array, forming pixel columns along a first direction and pixel rows along a second direction, when all subpixels on the display panel emit light, they affect each other. The first leakage level is used to evaluate the leakage between individual subpixels. When a subpixel emits light, it affects adjacent, non-emitting subpixels. This is considered lateral leakage, and the second leakage level is used to evaluate the lateral leakage of the subpixels.

[0062] Please see Figure 2-3 The present application provides an OLED test structure, comprising a test area, wherein the test area includes:

[0063] A plurality of sub-pixels 2, wherein the plurality of sub-pixels 2 form a plurality of pixel columns arranged in an array, and the sub-pixels 2 in each pixel column are arranged in parallel;

[0064] A first test terminal 3, comprising an electrode ring 31, the electrode ring 31 being disposed around the test area and having a semi-enclosed structure;

[0065] It also includes a second test terminal 4 or a third test terminal 5, wherein,

[0066] The second test terminal 4 is connected to each of the pixel columns;

[0067] The third test terminal 5 includes an odd column connection terminal 51 and an even column connection terminal 52 . The odd column connection terminal 51 is connected to odd pixel columns, and the even column connection terminal 52 is connected to even pixel columns.

[0068] It should be noted that in the embodiments of this application, pixel columns are used as an example for description. Since the first direction and the second direction can be perpendicular to each other or nearly perpendicular, this application does not limit the specific directions of the first direction and the second direction. Of course, in other embodiments, the first direction and the second direction can be interchangeable, such that the first direction can be the direction of pixel column arrangement and the second direction can be the direction of pixel row arrangement.

[0069] In the embodiments of the present application, the pixel columns can be arranged in the first direction or in the second direction. The present application does not limit the arrangement direction of the sub-pixels 2 in the pixel columns. Therefore, the "pixel columns" described in the embodiments of the present application can also be referred to as "pixel rows."

[0070] It is also worth noting that since the pixel leakage rating in the embodiment of the present application is divided into two types, when setting, the first test terminal 3 is freely combined with the second test terminal 4 or the third test terminal 5. In the embodiment of the present application, the combination of the first test terminal 3 and the second test terminal 4 or the first test terminal 3 and the third test terminal 5 is used in the test area, and the present application does not limit this. In the embodiment of the present application, the first test area 11 is described as a combination of the first test terminal 3 and the second test terminal 4, and the second first test area 11 is described as a combination of the first test terminal 3 and the third test terminal 5.

[0071] In the embodiment of the present application, the sub-pixel 2 includes a light-emitting element and an anode 100 and a cathode 200 located on both sides of the light-emitting element. The cathode 200 of the light-emitting element is connected to the first test terminal 3, and the anode 100 of the light-emitting element is connected to the second test terminal 4 or the third test terminal 5.

[0072] In the embodiments of the present application, the sub-pixel 20 can adopt various structures known in the prior art, and the present application is not limited thereto. For example, in addition to including a hole injection layer HIL 301, a hole transport layer HTL 302, an emitting layer 300 (Emitting Layer; EML), an electron transport layer ETL 304, and an electron injection layer EIL 303, the light-emitting element may also include a luminescence adjustment layer (Emitting Prime Layer), a hole blocking layer (HBL), etc.

[0073] In the embodiment of the present application, the sub-pixels 2 include a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B arranged in an array. Although each pixel is described as including an R sub-pixel unit, a G sub-pixel unit, and a B sub-pixel unit, the present invention is not limited thereto. The colors of the sub-pixels 2 can also be described as a first color, a second color, and a third color, and the first color, second color, and third color can also be cyan, magenta, and yellow. In addition, the pixel can include a white sub-pixel 2.

[0074] In the embodiment of the present application, the arrangement of the sub-pixels 20 in each pixel unit is not limited, and the sub-pixels 20 may be arranged in a stripe shape, an island shape, a mosaic shape, or a herringbone shape.

[0075] It should be noted that the embodiment of the present invention only uses the hexagonal shape of each sub-pixel 20 as an example. Optionally, the shape of each sub-pixel 20 can also be non-polygonal, such as the shape of the sub-pixel 20 can be circular or elliptical, and the embodiment of the present invention does not limit this. The shape of each sub-pixel 20 can be any one of a triangle, a quadrilateral, a pentagon, a hexagon, or an octagon. In actual applications, the shape can be flexibly set according to actual conditions such as the application of the display panel or the display effect requirements.

[0076] Example 1

[0077] like Figure 2 As shown, the test area includes a first test area 11 , on which the second test terminal 4 and the first test terminal 3 are disposed; in the first test area 11 , the first test terminal 3 and the second test terminal 4 are disposed on the same layer.

[0078] During configuration, the first test terminal 3 surrounds the first test area 11, and a first cathode pad is provided on the first test terminal 3, while an anode pad 41 is provided on the second test terminal 4. The electrode ring 31 on the first test terminal 3 surrounds three of the four sides of the first test area 11, and the cathode pad 32 and the anode pad 41 are located on the other side of the four sides of the test area. The second test terminal 4 also includes a plurality of first connecting wires 42 connected to the anode pad 41, with each first connecting wire 42 being connected to one of the pixel columns.

[0079] It should be noted that in the embodiment of the present application, the first test terminal 3 is a semi-annular electrode ring 31, which is arranged on the same layer as the anode 100 of the sub-pixel 2. The electrode ring 31 is connected to the cathode 200 of the sub-pixel 2 and is used to provide a cathode 200 potential to the cathode 200 of the sub-pixel 2. In the embodiment of the present application, the cathode 200 can be in the form of a common layer. When provided, one or more vias 600 can be provided between the cathode 200 and the electrode ring 31. The position and number of the vias 600 are not limited in the present application.

[0080] In the embodiment of the present application, the second test terminal 4 is used to connect to the anode 100 of the sub-pixel 2, so as to form a parallel arrangement of the sub-pixels 2 in each pixel row. In the embodiment of the present application, the second test terminal 4 is arranged in the same layer as the anode 100 of the sub-pixel 2, so the second test terminal 4 can be a strip electrode connected to each anode 100 in the pixel row. Of course, in other embodiments, each strip electrode in the second test terminal 4 can directly replace the anode 100 of the sub-pixel 2, or a strip electrode connected to each anode 100 can be used, and this application is not limited thereto.

[0081] like Figure 4 and Figure 5 As shown, the present application provides a method for preparing an OLED test structure, which is used to prepare any of the above-mentioned OLED test structures, and the method comprises:

[0082] S02: Provide a base substrate 10.

[0083] It should be noted that the base substrate 10 described in the present invention can be a glass substrate 10 or a flexible substrate 10, and the base substrate 10 has a pixel electrode pattern. The pixel electrode pattern area is used to make pixel electrodes. When the OLED display panel is a PM panel (passive panel), it does not have a driving TFT array. When the OLED display panel is an AM panel (active panel), the substrate 10 has a driving TFT array.

[0084] S04 , forming a first anode layer 101 on the base substrate 10 , and patterning the anode 100 of the sub-pixel 2 .

[0085] S06 , forming a second anode layer 102 on the base substrate 10 , and patterning the first test terminal 3 and the second test terminal 4 .

[0086] In the embodiment of the present application, the anode 100 can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the anode 100 is a transmissive electrode, the anode 100 can be formed using a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO). When the anode 100 is a semi-transmissive electrode or a reflective electrode, the anode 100 can include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a metal mixture.

[0087] It should be noted that, in the embodiment of the present application, the anode 100 structure of the sub-pixel 2 includes a first portion formed by the first anode layer 101101 and a second portion formed by the second anode layer 102102. The first test terminal 3 and the second test terminal 4 are formed by the second anode layer 102102. Because the anode 100 structure has its own shape, in the embodiment of the present application, the shapes of the anode 100, the first test terminal 3, and the second test terminal 4 are formed through two masking processes.

[0088] S08 , forming a pixel defining layer 500 on the second anode layer 102 , and patterning the layer to form a sub-pixel 2 region and a via hole 600 region.

[0089] In the embodiment of the present application, the material of the pixel defining layer 500 can be an organic material or an inorganic material, such as hybrid resin materials such as polysiloxane and polysilazane called spin-on glass (SOG), and inorganic materials such as silicon nitride, silicon oxide, and aluminum oxide.

[0090] S10 , forming the light-emitting element, cathode 200 and via 600 of the sub-pixel 2 on the pixel definition layer 500 .

[0091] In the embodiment of the present application, the cathode 200 can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the cathode 200 is a transmissive electrode, the cathode 200 can be formed using a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO). When the cathode 200 is a semi-transmissive electrode or a reflective electrode, the cathode 200 can include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a metal mixture.

[0092] In addition to the hole injection layer HIL 301, the hole transport layer HTL 302, the emitting layer 300 (Emitting Layer; EML), the electron transport layer ETL 304, and the electron injection layer EIL 303, the light emitting element may also include an emitting prime layer (Emitting Prime Layer), a hole blocking layer (HBL), etc.

[0093] It is worth noting that in the embodiments of the present application, the structural arrangement of the sub-pixel 2 is not limited. In some embodiments, except for the anode 100 and the light-emitting layer 300, which are independently arranged in the sub-pixel 2, the other layers are common layers. Of course, in the present application, there is no limit on the number of common layers, and the provision of common layers can save costs, etc. In the present application, the structure of the light-emitting element using common layers or independent layers can be tested.

[0094] It should be noted that in the embodiments of the present disclosure, "same layer" refers to a layer structure formed by using the same film-forming process to form a film layer for forming a specific pattern, and then using the same mask through a single patterning process. In the field of display technology, the patterning process described in this application may include only a photolithography process, or may include a photolithography process and an etching step, and may also include other processes such as printing and inkjet for forming a predetermined pattern; a photolithography process refers to a process that uses photoresist, a mask, an exposure machine, etc. to form a pattern, including film formation, exposure, and development processes. The corresponding patterning process can be selected based on the structure formed in the present invention.

[0095] like Figure 6 As shown, the present application also provides an OLED testing device, which adopts any of the test structures described above, including a first testing unit 1000, wherein the first testing unit 1000 includes a first signal sending module 1001 and a first signal detection module 1002. The first signal sending module 1001 is used to send a test signal to the first detection terminal and the second detection terminal. The first signal detection module 1002 is used to detect the current on the second detection terminal.

[0096] In the embodiment of the present application, the first test unit 1000 is bonded to the cathode pad 32 on the first test terminal 3 and the anode pad 41 on the second test terminal 4 through an IC or an FPC to send a test signal to the first test area 11 and receive a test result.

[0097] In an embodiment of the present application, a voltage output control circuit is provided on the first test unit 1000 for inputting a test voltage to the first test area 11. The first test unit 1000 is also provided with a current acquisition power supply for acquiring the current conditions on the display panel during the test.

[0098] The first test unit 1000 communicates with the computer in real time. The computer control system sends commands to the test unit, providing a user-friendly human-machine interface for parameter settings. The voltage output mode, current acquisition mode, voltage step value, and current step value can be set. The collected data is sent to the computer, which stores the data in a database. Data analysis includes calculating voltage and current values, plotting voltage-current characteristics, and leakage level characteristics. The test process status can also be monitored at any time through the interface, demonstrating the simplicity of the test system.

[0099] like Figure 7 As shown, an embodiment of the present application provides an OLED testing method, using the OLED testing device as described above, the method includes executing the following methods:

[0100] A cathode potential is input through the first test terminal 3 , and an anode potential is input through the second test terminal 4 , so as to obtain a first current value on the second test terminal 4 .

[0101] The first leakage level of the test area is equal to the first current value / the total number of sub-pixels 2 in the test area, L1=I1 / M 总 Where L1 is the first leakage level, I1 is the first current value, M 总 is the total number of sub-pixels 2 in the first test area 11 .

[0102] In the embodiment of the present application, the anode potential is input through the second test terminal 4 and the cathode potential is input through the first test terminal 3 in the first test area 11, so that each sub-pixel 2 can be lit up at the same time. The current data on the second test terminal 4 is collected through the current collection device. Of course, the current data on the first test terminal 3 can also be collected. This application does not limit this.

[0103] Example 2

[0104] like Figure 3 As shown, the test area includes a second test area 12 , on which the third test terminal 5 and the first test terminal 3 are disposed. In the second test area 12 , the first test terminal 3 and the third test terminal 5 are disposed on the same layer.

[0105] The first test terminal 3 surrounds the second test area 12, and a second cathode pad is provided on the second test area 12. The third test terminal 5 includes odd-numbered pads 51 and even-numbered pads 52. The electrode ring 31 on the first test terminal 3 surrounds three of the four sides of the second test area 12. One of the odd-numbered pads 51 and the even-numbered pads 52 is located on the other of the four sides of the test area, and the other of the odd-numbered pads 51 and the even-numbered pads 52 is located on the same side as the cathode pad 32.

[0106] In addition, the third test terminal also includes a plurality of second connection lines 53 connected to the odd column pads 51, and each of the second connection lines 53 is connected to an odd pixel column. The third test terminal also includes a plurality of third connection lines 54 connected to the even column pads 52, and one of the third connection lines 54 is connected to an even pixel column.

[0107] It should be noted that in the embodiment of the present application, the first test terminal 3 is a semi-annular electrode ring 31, which is arranged on the same layer as the anode 100 of the sub-pixel 2. The electrode ring 31 is connected to the cathode 200 of the sub-pixel 2 and is used to provide a cathode potential to the cathode 200 of the sub-pixel 2. In the embodiment of the present application, the cathode 200 can be in the form of a common layer. When provided, one or more vias 600 can be provided between the cathode 200 and the electrode ring 31. The position and number of the vias 600 are not limited in the present application.

[0108] In an embodiment of the present application, the third test terminal 5 is used to be connected to the anode 100 of the sub-pixel 2, and is used to apply different voltages to the odd pixel columns and the even pixel columns, respectively. In an embodiment of the present application, the method can be to apply the anode 100 voltage to the even pixel column to make the even pixel column emit light, and ground the odd pixel column, and not apply voltage to the odd pixel column, that is, the odd pixel column does not actively emit light, and emit light through the even pixel column, and test the current value on the odd column to obtain the lateral leakage condition of the sub-pixel 2; or the method can be to apply the anode 100 voltage to the odd pixel column to make the odd column emit light, and ground the even pixel column, and not apply voltage to the even pixel column, that is, the even pixel column does not actively emit light, and emit light through the odd pixel column, and test the current value on the even column to obtain the lateral leakage condition of the sub-pixel 2.

[0109] In the embodiment of the present application, the third test terminal 5 is provided in the same layer as the anode 100 of the sub-pixel 2. Therefore, the third test terminal 5 can be a strip electrode connected to each anode 100 in the pixel row. Of course, in other embodiments, each strip electrode in the third test terminal 5 can directly replace the anode 100 of the sub-pixel 2, or a strip electrode connected to each anode 100 can be used, and this application is not limited thereto.

[0110] like Figure 8-9 As shown, the present application provides a method for preparing an OLED test structure, which is used to prepare any of the above-mentioned OLED test structures, and the method comprises:

[0111] ST02: Provide a base substrate 10.

[0112] It should be noted that the base substrate 10 described in the present invention can be a glass substrate 10 or a flexible substrate 10, and the base substrate 10 has a pixel electrode pattern. The pixel electrode pattern area is used to make pixel electrodes. When the OLED display panel is a PM panel (passive panel), it does not have a driving TFT array. When the OLED display panel is an AM panel (active panel), the substrate 10 has a driving TFT array.

[0113] ST04 , forming a first anode layer 101 on the base substrate 10 , and patterning the anode 100 of the sub-pixel 2 .

[0114] ST06 , forming a second anode layer 102 on the base substrate 10 , and patterning the first test terminal 3 and the third test terminal 5 .

[0115] In the embodiment of the present application, the anode 100 can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the anode 100 is a transmissive electrode, the anode 100 can be formed using a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO). When the anode 100 is a semi-transmissive electrode or a reflective electrode, the anode 100 can include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a metal mixture.

[0116] It should be noted that, in the embodiment of the present application, the anode 100 structure of the sub-pixel 2 includes a first portion formed by the first anode layer 101101 and a second portion formed by the second anode layer 102102. The structures of the first test terminal 3 and the third test terminal 5 are formed by the second anode layer 102102. Because the anode 100 structure has its own shape, in the embodiment of the present application, the shapes of the anode 100, the first test terminal 3, and the third test terminal 5 are formed through two mask processes.

[0117] ST08 , forming a pixel defining layer 500 on the second anode layer 102 , and patterning the layer to form a sub-pixel 2 region and a via hole 600 region.

[0118] In the embodiment of the present application, the material of the pixel defining layer 500 can be an organic material or an inorganic material, such as hybrid resin materials such as polysiloxane and polysilazane called spin-on glass (SOG), and inorganic materials such as silicon nitride, silicon oxide, and aluminum oxide.

[0119] ST10 , forming the light-emitting element, cathode 200 and via hole 600 of the sub-pixel 2 on the pixel definition layer 500 .

[0120] In the embodiment of the present application, the cathode 200 can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the cathode 200 is a transmissive electrode, the cathode 200 can be formed using a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO). When the cathode 200 is a semi-transmissive electrode or a reflective electrode, the cathode 200 can include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a metal mixture.

[0121] In addition to the hole injection layer HIL 301, the hole transport layer HTL 302, the emitting layer 300 (Emitting Layer; EML), the electron transport layer ETL 304, and the electron injection layer EIL 303, the light emitting element may also include an emitting prime layer (Emitting Prime Layer), a hole blocking layer (HBL), etc.

[0122] It is worth noting that in the embodiments of the present application, the structural arrangement of the sub-pixel 2 is not limited. In some embodiments, except for the anode 100 and the light-emitting layer 300, which are independently arranged in the sub-pixel 2, the other layers are common layers. Of course, in the present application, there is no limit on the number of common layers, and the provision of common layers can save costs, etc. In the present application, the structure of the light-emitting element using common layers or independent layers can be tested.

[0123] like Figure 10 As shown, an embodiment of the present application further provides an OLED testing device, which adopts any of the test structures described above and includes a second testing unit 2000, wherein the second testing unit 2000 includes a second signal sending module 2001 and a second signal detection module 2002. The second signal sending module 2001 is used to send a test signal to the first detection terminal and the third detection terminal. The second signal detection module 2002 is used to detect the current on the third detection terminal.

[0124] In the embodiment of the present application, the second test unit 2000 is bonded to the cathode pad 32 on the first test terminal 3, the even column pad 52, and the odd column pad 51 on the third test terminal 5 through an IC or an FPC, thereby sending a test signal to the second test area 12 and receiving the test results.

[0125] In an embodiment of the present application, the second test unit 2000 is provided with a voltage output control circuit for inputting a test voltage to the second test area 12. The second test unit 2000 is also provided with a current acquisition power supply for collecting the current conditions on the display panel during the test.

[0126] The second test unit 2000 communicates with the computer in real time. The computer control system sends commands to the test unit, providing a user-friendly human-machine interface for parameter settings. The voltage output mode, current acquisition mode, voltage step value, and current step value can be set. The collected data is sent to the computer, which stores the data in a database. Data analysis includes calculating voltage and current values, plotting voltage-current characteristics, and leakage level characteristics. The test process status can also be monitored at any time through the interface, demonstrating the simplicity of the test system.

[0127] like Figure 11 As shown, an embodiment of the present application provides an OLED testing method, using the OLED testing device as described above, the method includes performing one or more of the following methods:

[0128] A cathode potential is input through the first test terminal 3 , an anode potential is input through the odd-numbered column connection terminal 51 in the third test terminal 5 , and a zero potential is input through the even-numbered column connection terminal 52 to obtain a second current value on the even-numbered column connection terminal 52 .

[0129] The second leakage level of the test area is equal to the second current value / the total number of sub-pixels 2 in the even pixel columns in the test area. L2 = I2 / M 偶总2 Where L2 is the second leakage level, I2 is the second current value, M 偶总2 is the total number of sub-pixels 2 in the even-numbered pixel columns in the second test area 12 .

[0130] A cathode potential is input through the first test terminal 3 , an anode potential is input through the even-numbered column connection terminal 52 in the third test terminal 5 , and a zero potential is input through the odd-numbered column connection terminal 51 to obtain a third current value on the odd-numbered column connection terminal 51 .

[0131] The second leakage level of the test area is equal to the third current value / the total number of sub-pixels 2 in the odd pixel columns in the test area. L2 = I3 / M 奇总2 Where L2 is the second leakage level, I3 is the third current value, and M 奇总2 is the total number of sub-pixels 2 in the odd-numbered pixel columns in the second test area 12 .

[0132] A cathode potential is input through the first test terminal 3, and the same anode potential is input through the odd column connection terminal 51 and the even column connection terminal 52 in the third test terminal 5 to obtain a fourth current value on the odd column connection terminal 51, or a fifth current value on the even column connection terminal 52.

[0133] The first leakage level of the test area is equal to the fourth current value / the total number of sub-pixels 2 in the test area. L1=I4 / M 总2 Where L1 is the first leakage level, I4 is the fourth current value, M 总2 is the total number of sub-pixels 2 in the second test area 12 .

[0134] Alternatively, the first leakage level of the test area is equal to the fifth current value / the total number of sub-pixels 2 in the test area. L1=I5 / M 总2 Where L1 is the first leakage level, I5 is the fifth current value, M 总2 is the total number of sub-pixels 2 in the second test area 12 .

[0135] It should be noted that in the embodiment of the present application, when the odd pixel columns and the even pixel columns are both connected to the same anode potential, the sub-pixels 2 in the odd pixel columns and the even pixel columns are all illuminated. When the current value at one end is tested, the first leakage level is obtained. The principle is the same as in Example 1 and will not be repeated in this embodiment; when one of the pads is connected to the anode potential and the other is grounded, the second leakage level is measured. In application, any choice can be made and this application does not limit this. When the number of odd and even columns is the same, the test results of the odd and even columns are the same. When there are more odd columns than even columns, it is preferred that the odd columns emit light and the even columns are tested.

[0136] It should be noted that in the embodiment of the present application, when calculating the second leakage level, when the even pixel columns are collected, the right side of the equation is the total number of sub-pixels 2 in the even pixel columns, and when the odd pixel columns are collected, the right side of the equation is the total number of sub-pixels 2 in the odd pixel columns.

[0137] It should also be noted that the second test area 12 can be used to test the first leakage level or the second leakage level, and this application does not limit this. It is also worth noting that the first test area 11 and the second test area 12 can be set in different areas on the same display panel, or can be set on different display panels, and this application does not limit this.

[0138] The OLED test structure provided in the embodiment of the present application is arranged on the anode 100 layer of the display panel, is simple to prepare, and can be used to test the leakage of the OLED. When used, various test structures can be arranged according to the test requirements to achieve tests for different leakage levels; this provides a convenient reference for subsequent OLED design and process preparation.

[0139] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0140] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0141] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art in the art of the present invention. The terms used herein are only for describing specific implementation purposes and are not intended to limit the present invention. Terms such as "setting" appearing in this article can mean that one component is directly attached to another component, or that one component is attached to another component through an intermediate component. Features described in this article in one embodiment can be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or otherwise specified.

[0142] The present invention has been described through the above embodiments, but it should be understood that the above embodiments are for illustrative and illustrative purposes only and are not intended to limit the present invention to the described embodiments. Those skilled in the art will appreciate that various variations and modifications may be made based on the teachings of the present invention, and such variations and modifications fall within the scope of protection claimed in the present invention.

Claims

1. An OLED test structure, characterized in that: The method comprises a test area, wherein the test area comprises a first test area and a second test area, wherein the test area comprises: A plurality of sub-pixels, the plurality of sub-pixels forming a plurality of pixel columns arranged in an array, the sub-pixels in each pixel column being arranged in parallel, the sub-pixels comprising a light-emitting element and an anode and a cathode located on both sides of the light-emitting element; a first test terminal, wherein the first test terminal includes an electrode ring, the electrode ring is arranged around the test area, and the electrode ring has a semi-enclosed structure; It also includes a second test terminal or a third test terminal, wherein the second test terminal is suitable for the first test area, and the third test terminal is suitable for the second test area; Wherein, the second test terminal is connected to each of the pixel columns; The third test terminal includes an odd column connection terminal and an even column connection terminal, the odd column connection terminal is connected to the odd pixel column, and the even column connection terminal is connected to the even pixel column; The anode of the light emitting element is connected to the second test terminal or the third test terminal; inputting a cathode potential through the first test terminal and an anode potential through the second test terminal to obtain a first current value on the second test terminal; inputting a cathode potential through the first test terminal, inputting an anode potential through the odd-numbered connection terminals in the third test terminal, and inputting a zero potential through the even-numbered connection terminals, to obtain a second current value on the even-numbered connection terminals; inputting a cathode potential through the first test terminal, inputting an anode potential through the even-numbered connection terminals in the third test terminal, and inputting a zero potential through the odd-numbered connection terminals, to obtain a third current value on the odd-numbered connection terminals; Inputting a cathode potential through the first test terminal, inputting the same anode potential through the odd-numbered column connection terminals and the even-numbered column connection terminals of the third test terminal, and obtaining a fourth current value on the odd-numbered column connection terminals, or obtaining a fifth current value on the even-numbered column connection terminals; Among them, the first current value, the fourth current value and the fifth current value are used to evaluate the first leakage level, the first leakage level is used to evaluate the leakage situation between single sub-pixels, the second current value and the third current value are used to evaluate the second leakage level, and the second leakage level is used to evaluate the lateral leakage situation of sub-pixels.

2. The OLED test structure according to claim 1, wherein: The test area includes a first test area, and the second test terminal and the first test terminal are arranged on the first test area; the first test terminal and the second test terminal are arranged on the same layer in the first test area.

3. The OLED test structure according to claim 2, wherein: The first test terminal surrounds the first test area. A first cathode pad is provided on the first test terminal, and an anode pad is provided on the second test terminal.

4. The OLED test structure according to claim 3, wherein: The electrode ring surrounds three sides of the first test area, and the cathode pad and the anode pad are located on the other side of the four sides of the test area.

5. The OLED test structure according to claim 3, wherein: The second test terminal further includes a plurality of first connection lines connected to the anode pad, and each of the first connection lines is connected to one of the pixel columns.

6. The OLED test structure according to claim 1, wherein: The test area includes a second test area, the third test terminal and the first test terminal are arranged on the second test area, and the first test terminal and the third test terminal are arranged on the same layer in the second test area.

7. The OLED test structure according to claim 6, wherein: The first test terminal surrounds the second test area. A second cathode pad is provided on the first test area. The third test terminal includes an odd-numbered column pad and an even-numbered column pad.

8. The OLED test structure according to claim 7, wherein: The electrode ring surrounds three of the four sides of the second test area, one of the odd-numbered column pads and the even-numbered column pads is located on the other of the four sides of the test area, and the other of the odd-numbered column pads and the even-numbered column pads is located on the same side as the cathode pad.

9. The OLED test structure according to claim 7, wherein: The third test terminal also includes a plurality of second connection lines connected to the odd column pads, and each of the second connection lines is connected to an odd pixel column. The third test terminal also includes a plurality of third connection lines connected to the even column pads, and one of the third connection lines is connected to an even pixel column.

10. A method for preparing an OLED test structure, characterized in that: For preparing the OLED test structure according to any one of claims 1 to 9, the method comprises: providing a substrate; forming a first anode layer on the base substrate and patterning the anode layer to form a sub-pixel; forming a second anode layer on the base substrate, and patterning the first test terminal and one of the second test terminal and the third test terminal; forming a pixel defining layer on the second anode layer, and patterning the layer to form a sub-pixel region and a via region; A light emitting element, a cathode and a via hole of the sub-pixel are formed on the pixel defining layer.

11. An OLED testing device, characterized in that: The test structure according to any one of claims 1 to 9 includes a first test unit or a second test unit, wherein: The first test unit includes a first signal sending module and a first signal detection module, the first signal sending module is used to send a test signal to the first detection terminal and the second detection terminal; the first signal detection module is used to detect the current on the second detection terminal; The second test unit includes a second signal sending module and a second signal detection module. The second signal sending module is used to send a test signal to the first detection terminal and the third detection terminal; the second signal detection module is used to detect the current on the third detection terminal.

12. An OLED testing method, characterized in that: Using the OLED testing device according to claim 11, the method includes performing one or more of the following: inputting a cathode potential through the first test terminal and an anode potential through the second test terminal to obtain a first current value on the second test terminal; inputting a cathode potential through the first test terminal, inputting an anode potential through the odd-numbered connection terminals in the third test terminal, and inputting a zero potential through the even-numbered connection terminals, to obtain a second current value on the even-numbered connection terminals; inputting a cathode potential through the first test terminal, inputting an anode potential through the even-numbered connection terminals in the third test terminal, and inputting a zero potential through the odd-numbered connection terminals, to obtain a third current value on the odd-numbered connection terminals; A cathode potential is input through the first test terminal, and the same anode potential is input through the odd-numbered column connection terminal and the even-numbered column connection terminal in the third test terminal to obtain a fourth current value on the odd-numbered column connection terminal, or to obtain a fifth current value on the even-numbered column connection terminal.

13. The OLED testing method according to claim 12, wherein: The leakage level of the test area is characterized by at least one of the following: The first leakage level of the test area is equal to the first current value / the total number of sub-pixels in the test area; The second leakage level of the test area is equal to the second current value / the total number of sub-pixels in the even-numbered pixel columns in the test area; The second leakage level of the test area is equal to the third current value / the total number of sub-pixels in the odd-numbered pixel columns in the test area; The first leakage level of the test area is equal to the fourth current value / the total number of sub-pixels in the test area; The first leakage level of the test area is equal to the fifth current value / the total number of sub-pixels in the test area.

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