Display testing device and testing method thereof

Abstract

The application discloses a display testing device and a testing method thereof. The display testing device comprises a display panel and a testing module. The display panel comprises a plurality of light emitting devices and a plurality of testing tracks. The first light emitting device comprises a first electrode, a second electrode and a light emitting layer between the first electrode and the second electrode. The dummy light emitting device comprises the first electrode and the second electrode. The first light emitting group comprises two adjacent first light emitting devices arranged along a first direction, and the dummy light emitting group comprises two adjacent dummy light emitting devices arranged along the first direction. The testing module is connected with the first electrode of the first light emitting group and the first electrode of the dummy light emitting group through the testing tracks, and is used for measuring a first resistance parameter between the two adjacent first light emitting devices and a second resistance parameter between the two adjacent dummy light emitting devices, and detecting whether the first resistance parameter and the second resistance parameter meet the panel manufacturing condition. In the application, the panel testing is realized to improve the production yield.

Description

Technical Field

[0001] This invention relates to the field of display panel technology, and in particular to a display testing device and its testing method. Background Technology

[0002] To meet user needs, the research and development direction of display panels includes improving the display effect, and increasing the resolution of the display panel can effectively improve the display effect.

[0003] However, in high-resolution display panels, the spacing between adjacent sub-pixels becomes increasingly smaller, making manufacturing more difficult. This results in lower yield rates during mass production. Summary of the Invention

[0004] This invention provides a display testing device and method to solve the problem of low yield in existing panel production.

[0005] According to one aspect of the present invention, a display testing apparatus is provided, comprising: a display panel and a testing module; The display panel includes multiple light-emitting devices and multiple test traces. The multiple light-emitting devices include first light-emitting devices and dummy light-emitting devices. The first light-emitting device includes a first electrode, a second electrode, and a light-emitting layer located between the first electrode and the second electrode. The dummy light-emitting device includes the first electrode and the second electrode. The multiple light-emitting devices include a first light-emitting group and a dummy light-emitting group. The first light-emitting group includes two adjacent first light-emitting devices arranged along a first direction, and the dummy light-emitting group includes two adjacent dummy light-emitting devices arranged along the first direction. The test module includes multiple signal terminals, and each signal terminal is connected to a test trace. The test module is connected to the first electrode of the first light-emitting group and the first electrode of the dummy light-emitting group through the test traces, and is used to measure the first resistance parameter between two adjacent first light-emitting devices and the second resistance parameter between two adjacent dummy light-emitting devices, and to detect whether the first resistance parameter and the second resistance parameter meet the panel manufacturing conditions.

[0006] Furthermore, at least one of the two adjacent first light-emitting devices has a first sub-region and a second sub-region as its first electrode, and the test module is connected to the first sub-region and the second sub-region respectively through two test traces; The two adjacent first light-emitting devices satisfy at least one of the following conditions: 1) The test module provides a first current signal to the first sub-region of the first light-emitting device; 2) The test module provides a ground signal to the second sub-region of the second first light-emitting device; 3) The test module measures the first resistance parameter between the second sub-region of the first first light-emitting device and the first sub-region of the second first light-emitting device.

[0007] Furthermore, the first electrode includes a first sub-electrode and a second sub-electrode spaced apart, the first sub-electrode serving as the first sub-region and the second sub-electrode serving as the second sub-region.

[0008] Furthermore, the first sub-electrode and the second sub-electrode in the first electrode are arranged along the first direction; Alternatively, the second sub-electrode surrounds the first sub-electrode; Alternatively, the first sub-electrode may surround the second sub-electrode.

[0009] Furthermore, the first light-emitting group includes a first light-emitting device arranged along the first direction, two adjacent first light-emitting devices, and a second light-emitting device; The test module is used to provide a first current signal to the first light-emitting device and a ground signal to the second light-emitting device.

[0010] Furthermore, at least one of the first light-emitting device and the second light-emitting device is the dummy light-emitting device.

[0011] Furthermore, the panel manufacturing conditions include: -5%≤(R AA -R DA ) / R DA ≤+5%; Among them, R AA Let R be the first resistance parameter. DA This refers to the second resistor parameter; Both the first resistance parameter and the second resistance parameter are resistance values, or both the first resistance parameter and the second resistance parameter are sheet resistance values.

[0012] Furthermore, the display panel includes: Substrate; A first metal layer located on one side of the substrate, the first metal layer including the plurality of test traces; The pixel defining layer is located on the side of the first metal layer opposite to the substrate, and the plurality of light-emitting devices are also present. The pixel defining layer includes a plurality of pixel openings, and the light-emitting devices overlap with the pixel openings in a direction perpendicular to the substrate. The test trace is connected to the corresponding first electrode via a via.

[0013] According to another aspect of the present invention, a test method for a display testing apparatus is provided, applied to the display testing apparatus as described above, the test method comprising: Measure the first resistance parameter between two adjacent first light-emitting devices in the first light-emitting group, and measure the second resistance parameter between two adjacent dummy light-emitting devices in the dummy light-emitting group; If the first resistance parameter and the second resistance parameter are found to meet the panel manufacturing conditions, the corresponding display panel process parameters are determined as the target process parameters.

[0014] Furthermore, the panel manufacturing conditions include: -5%≤(R AA -R DA ) / R DA ≤+5%; Among them, R AA Let R be the first resistance parameter. DA This refers to the second resistor parameter; Both the first resistance parameter and the second resistance parameter are resistance values, or both the first resistance parameter and the second resistance parameter are sheet resistance values.

[0015] In this invention, the test module is connected to the display panel via test traces. It measures the second resistance parameter between dummy light-emitting devices and the first resistance parameter between first light-emitting devices. The second resistance parameter is used as the standard value for the resistance parameter between two adjacent light-emitting devices. The first and second resistance parameters can then be compared. If both meet the panel manufacturing conditions, the display panel has better uniformity and is suitable for mass production. Conversely, if they do not meet the panel manufacturing conditions, the display panel has poorer uniformity and is not suitable for mass production. By reasonably setting the panel manufacturing conditions and testing the display panel, a display panel that meets the manufacturing conditions can be obtained, with its process parameters within a reasonable range. Mass production of the panel based on the process parameters of the display panel that meets the manufacturing conditions will result in the second and first resistance parameters being close, indicating good display uniformity, which can improve production yield and reduce defect rate.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of two adjacent light-emitting devices; Figure 2 This is a schematic diagram of a display testing device provided in an embodiment of the present invention; Figure 3 yes Figure 2 A sectional view along A1-A2; Figure 4 This is a schematic diagram of another display testing device provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of another display testing device provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of a virtual light-emitting group provided in an embodiment of the present invention; Figure 7 yes Figure 6 A schematic diagram of the equivalent circuit; Figure 8 This is a schematic diagram of a first light-emitting group provided in an embodiment of the present invention; Figure 9 This is a schematic diagram of another first light-emitting group provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention; Figure 11 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention; Figure 13 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention; Figure 14 yes Figure 13 A schematic diagram of the first electrodes of two adjacent first light-emitting devices; Figure 15 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention; Figure 16 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention; Figure 17 This is a schematic diagram of a testing method for a display testing device provided in an embodiment of the present invention; Figure 18This is a schematic diagram of a testing device provided in an embodiment of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] To meet user needs, the research and development of display panels focuses on improving display performance, and increasing the resolution of display panels can effectively improve display performance. However, in high-resolution display panels, the spacing between adjacent sub-pixels becomes increasingly smaller, which can easily lead to crosstalk.

[0022] For OLED or micro OLED display panels, lateral leakage current from adjacent sub-pixels can cause crosstalk. During manufacturing, the OLED device layer resistance between sub-pixels is modulated to increase and nearly open-circuit the OLED device layer, thus reducing lateral leakage current and mitigating crosstalk. Here, the OLED device layer resistance refers to the resistance from the anode to the OLED device layer to the cathode.

[0023] Figure 1 This is a schematic diagram of two adjacent light-emitting devices, such as... Figure 1As shown, the light-emitting device 100 includes an OLED device layer 101 and a cathode 102 and an anode 103 disposed on both sides of the OLED device layer 101. The cathode 102 is typically composed of a MgAg alloy layer 102a and a transparent conductive layer 102b, wherein the MgAg alloy layer 102a is located between the transparent conductive layer 102b and the OLED device layer 101. Through an undercut structure, an undercut opening 111 is made in the pixel defining layer 110. Specifically, the undercut opening 111 is made at the ramp position of the pixel opening in the pixel defining layer 110. This allows the vapor-deposited OLED device layer 101 to become thinner at the undercut opening 111 position, thus increasing the resistance of the OLED device layer at the undercut opening 111 position. This reduces lateral leakage current between sub-pixels and improves crosstalk issues. The sub-pixel is the light-emitting device. Clearly, by increasing the depth of the undercut opening 111 along the F3 direction, it can be ensured that the vapor-deposited OLED device layer 101 is disconnected at the undercut opening 111. This increases the resistance of the OLED device layer at the undercut opening 111, making it nearly an open circuit, which further improves the crosstalk problem. It can be understood that adjusting the photolithography parameters of the pixel-defining layer 110 can affect the depth of the undercut opening 111.

[0024] A lower resistance of the cathode 102 on the OLED device layer 101 is more beneficial to display uniformity. However, increasing the depth of the bottom cut opening 111 along the F3 direction may cause the cathode 102 to thin out or even break at the bottom cut opening 111 location. This would increase the resistance of the cathode 102 at the bottom cut opening 111 location, leading to a larger voltage drop across the sub-pixels and reducing display uniformity. In other words, modulating the resistance of the OLED device layer 101 between sub-pixels can sometimes be accompanied by the side effect of increased resistance of the cathode 102, affecting display uniformity. Since there is no way to measure the resistance of the cathode 102 and the OLED device layer 101, the product yield will be reduced to some extent and costs will increase after the display panel is produced.

[0025] Based on the above, this invention provides a display testing device for testing display panels. Specifically, before mass production of display panels, multiple display panel samples are provided. These samples may have different photolithographic parameters for the pixel definition layer, different MgAg alloy layer thicknesses, or different transparent conductive layer thicknesses. The display testing device can test each display panel sample. After testing, the display panel with the best test results can be identified. The process parameters corresponding to this optimal display panel are then used as the target process parameters for subsequent mass production, which helps improve mass production yield. Clearly, the process parameters corresponding to the optimal display panel in a batch of samples are likely to best satisfy the following requirements: the undercut depth ensures that the evaporated OLED device layer is disconnected at the undercut opening; and the undercut depth does not cause the cathode to thin or even disconnect at the undercut opening. Mass production of display panels based on the process parameters corresponding to the optimal display panel can improve product yield.

[0026] Figure 2 This is a schematic diagram of a display testing device provided in an embodiment of the present invention. Figure 3 yes Figure 2 A cross-sectional view along A1-A2. This embodiment is applicable to situations where a display panel is being tested. Figure 2 and Figure 3 As shown, the display testing device includes: a test module 210 and a display panel 220; the display panel 220 includes multiple light-emitting devices 220a and multiple test traces 221, the multiple light-emitting devices 220a include a first light-emitting device 222 and a dummy light-emitting device 223; the first light-emitting device 222 includes a first electrode 224, a second electrode 225 and a light-emitting layer 226 located between the first electrode 224 and the second electrode 225; the dummy light-emitting device 223 includes a first electrode 224 and a second electrode 225; the multiple light-emitting devices 220a include a first light-emitting group 231 and a dummy light-emitting group 232, the first light-emitting group 231 includes a light-emitting layer 226 located between the first electrode 224 and the second electrode 225; the multiple light-emitting devices 220a include a first light-emitting group 231 and a dummy light-emitting group 232, the first light-emitting group 231 including a light-emitting layer 221 located along a first direction. The test module 210 includes multiple signal terminals, each connected to a test trace 221. The test module 210 is connected to the first electrode 224 of the first light-emitting group 231 and the first electrode 224 of the dummy light-emitting group 232 via the test trace 221. This is used to measure the first resistance parameter between two adjacent first light-emitting devices 222 and the second resistance parameter between two adjacent dummy light-emitting devices 223, and to detect whether the first and second resistance parameters meet the panel manufacturing conditions. It is understood that... Figure 2 and Figure 3 The structure of the display panel shown is only a part of the structure of the display panel. Other structures of the display panel will be described in detail in subsequent embodiments.

[0027] The display testing apparatus provided in this embodiment can be used to test display panels. For example, the apparatus can test multiple display panels of the same type, which have identical structures but different process parameters. After testing, the display panel with the best test results can be identified, and the process parameters corresponding to this panel can be set as the target process parameters for subsequent mass production, thus improving mass production yield. The apparatus can also test different types of display panels, facilitating the analysis and processing of relevant panel data based on the test results. The display panel can be an organic light-emitting display panel.

[0028] like Figure 2 As shown, the display testing apparatus includes a test module 210 and a display panel 220. The test module 210 is used to test multiple display panels 220 respectively. The test module 210 includes multiple signal terminals, and the display panel 220 includes multiple test traces 221. The signal terminals of the test module 210 are connected to the test traces 221 of the display panel 220. The test module 210 transmits signals to the display panel 220 through the test traces 221 to achieve the testing of the display panel 220. It can be understood that the test module 210 integrates all the components that realize the testing process, and some of its structure will be described in subsequent embodiments.

[0029] The display panel 220 includes multiple light-emitting devices 220a and multiple test traces 221. Optionally, the multiple light-emitting devices 220a can be arranged along a first direction F1 to form a pixel row, and the multiple pixel rows can be arranged along a second direction F2, with the first direction F1 and the second direction F2 intersecting. The test traces 221 are conductive metal wires and can be used to transmit signals. The pixel arrangement of the multiple light-emitting devices 220a in the display panel 220 can be as follows: Figure 2 The delta pixel arrangement is shown.

[0030] In other embodiments, the pixel arrangement of the multiple light-emitting devices in the display panel can also be a PI pixel arrangement or a matrix pixel arrangement. Figure 4 This is a schematic diagram of another display testing device provided in an embodiment of the present invention, such as... Figure 4 As shown, the pixel arrangement of the multiple light-emitting devices 220a in the display panel is a PI pixel arrangement. Figure 5 This is a schematic diagram of another display testing device provided in an embodiment of the present invention, such as... Figure 5 As shown, the pixel arrangement of the multiple light-emitting devices 220a in the display panel is a matrix pixel arrangement.

[0031] The multiple light-emitting devices 220a include multiple first light-emitting devices 222 and multiple dummy light-emitting devices 223. Each first light-emitting device 222 includes a first electrode 224, a second electrode 225, and a light-emitting layer 226 located between the first electrode 224 and the second electrode 225; each dummy light-emitting device 223 includes a first electrode 224 and a second electrode 225. It can be understood that the first electrode 224 of the light-emitting device 220a can be an anode, and the second electrode 225 of the light-emitting device 220a can be a cathode. The second electrode 225 of the organic light-emitting display panel is a surface electrode, that is, along the third direction F3, the second electrode 225 covers all light-emitting devices 220a. The first electrode 224 of the organic light-emitting display panel is an independent electrode, that is, the first electrodes 224 of two light-emitting devices 220a are independent and insulated from each other. The difference between the first light-emitting devices 222 and the dummy light-emitting devices 223 is that the first electrode 224 and the second electrode 225 are in direct contact in the dummy light-emitting device 223, while the first light-emitting device 222 includes a light-emitting layer 226. In other words, in practical applications, when the display panel is displaying, the first light-emitting device 222 can emit light, while the dummy light-emitting device 223 does not emit light. The F3 direction is perpendicular to both the F1 and F2 directions. The light-emitting layer 226 includes organic light-emitting material, and the multiple light-emitting devices 220a can include multiple first light-emitting devices 222 of different colors. For example, the multiple light-emitting devices 220a can include a first light-emitting device 222 configured to emit red light, a first light-emitting device 222 configured to emit green light, and a first light-emitting device 222 configured to emit blue light. In this embodiment, the emission color of the first light-emitting device 222 is not related to the testing process, therefore... Figure 2 The first light-emitting device 222 and the dummy light-emitting device 223 are distinguished only by different filled lines. Figure 3 The structure of the middle luminescent layer 226 can be related to Figure 1 The structure of the OLED device layer 101 is the same.

[0032] Multiple light-emitting devices 220a include a first light-emitting group 231 and a dummy light-emitting group 232. The first light-emitting group 231 includes two adjacent first light-emitting devices 222 arranged along the first direction F1, and the dummy light-emitting group 232 includes two adjacent dummy light-emitting devices 223 arranged along the first direction F1. It is understood that the position and number of the first light-emitting group 231 and the dummy light-emitting group 232 in the display panel 220 are not specifically limited. Depending on the testing requirements, the first light-emitting group 231 may include two adjacent first light-emitting devices 222 arranged along the F1 direction at any position in the display panel 220, and the dummy light-emitting group 232 may include two adjacent dummy light-emitting devices 223 arranged along the F1 direction at any position in the display panel 220. The test module 210 connects the first electrode 224 of the first light-emitting group 231 and the first electrode 224 of the dummy light-emitting group 232 respectively through test traces 221. In this embodiment, the first light-emitting group 231 and the dummy light-emitting group 232 are designed to be located in the same pixel row. However, in other embodiments, the first light-emitting group 231 and the dummy light-emitting group 232 may be located in different pixel rows.

[0033] It should be noted that the test module 210 is connected to the first electrode 224 of the first light-emitting group 231 and the first electrode 224 of the dummy light-emitting group 232 respectively via test traces 221. Taking the first light-emitting group 231 including two light-emitting devices 220a and the dummy light-emitting group 232 including two light-emitting devices 220a as an example, the test module 210 needs to be electrically connected to the first light-emitting group 231 and the dummy light-emitting group 232 via at least four test traces 221. The first electrode 224 of one light-emitting device 220a is connected to the test module 210 via at least one test trace 221, and each test trace 221 transmits a corresponding signal.

[0034] refer to Figure 3 As shown, the optional display panel includes: a substrate 201; a first metal layer 202 located on one side of the substrate 201, the first metal layer 202 including multiple test traces 221; a pixel defining layer 203 located on the side of the first metal layer 202 opposite to the substrate 201 and multiple light-emitting devices 220a, the pixel defining layer 203 including multiple pixel openings 203a, the light-emitting devices 220a overlapping the pixel openings 203a in a direction perpendicular to the substrate 201; the test traces 221 are connected to the corresponding first electrode 224 through vias 204.

[0035] Test module 210 is connected to the first electrode 224 of the first light-emitting group 231 via test traces 221, allowing measurement of the first resistance parameter between two adjacent first light-emitting devices 222 in the first light-emitting group 231. Test module 210 is also connected to the first electrode 224 of the dummy light-emitting group 232 via test traces 221, allowing measurement of the second resistance parameter between two adjacent dummy light-emitting devices 223 in the dummy light-emitting group 232. The second resistance parameter serves as a standard value for the resistance parameter between two adjacent light-emitting devices 220a. The smaller the difference between the first and second resistance parameters, the better the uniformity of the display panel; conversely, the larger the difference, the worse the uniformity of the display panel. Test module 210 can detect the degree of deviation between the first and second resistance parameters and determine whether this deviation meets the panel manufacturing conditions. Preset panel manufacturing conditions are included in test module 210, such as a deviation range of -5% to +5%.

[0036] Optional panel manufacturing conditions include: -5% ≤ (R AA -R DA ) / R DA ≤+5%; where R AA R is the first resistance parameter. DA The first resistance parameter is the second resistance parameter; both the first and second resistance parameters are resistance values, or both the first and second resistance parameters are sheet resistance values.

[0037] The dummy light-emitting device 223 in the display panel 220 does not include the light-emitting layer 226, so there is no undercut opening 227 in the dummy light-emitting device 223. The second electrode 225 is a surface electrode, so the ramp resistance of the second electrode 225 in the dummy light-emitting device 223 at the pixel opening 203a can be regarded as the standard resistance value of the second electrode 225 at the ramp position. The first light-emitting device 222 includes the light-emitting layer 226, so there is an undercut opening 227 in the first light-emitting device 222. The second electrode 225 in the first light-emitting device 222 starts to extend ramp along the pixel limiting layer 203 from the undercut opening 227 position. The closer the resistance of the second electrode 225 at the undercut opening 227 position is to the standard resistance value of the second electrode 225 in the dummy light-emitting device 223 at the ramp position, the more uniform the voltage drop distribution of the second electrode 225 between two adjacent first light-emitting devices 222 is. Conversely, the greater the deviation of the resistance of the second electrode 225 at the bottom cut opening 227 from the standard resistance value of the second electrode 225 at the ramp position in the dummy light-emitting device 223, the greater the voltage drop of the second electrode 225 between two adjacent first light-emitting devices 222, which affects the uniformity of the display.

[0038] Figure 6 This is a schematic diagram of a virtual light-emitting group provided in an embodiment of the present invention. Figure 6 As shown in the figure, the dummy light-emitting group comprises 4 dummy light-emitting devices 223 sequentially arranged along the direction F1, and first electrodes 224 of the 4 dummy light-emitting devices 223 are sequentially connected to test traces 221a to 221d. A test module (not shown) is connected to the test traces 221a to 221d respectively. The test module comprises a voltmeter 211. The test module provides a first current signal I+ to the first test trace 221a, and provides a ground signal GND to the fourth test trace 221d to ground the same. The voltmeter 211 is connected between the second test trace 221b and the third test trace 221c, and can measure and obtain a resistance value Rc between two adjacent dummy light-emitting devices 223 in the dummy light-emitting group, and optionally, this resistance value is the second resistance parameter. It can be understood that the test module further comprises a current source for providing a current signal to the test traces.

[0039] Figure 7 is Figure 6 a schematic diagram of the equivalent circuit of. In combination with Figure 6 and Figure 7 shown in , the resistance Rc of the second electrode 225 between P1 and P2 can be tested and obtained. Specifically, the process is as follows: 1) The total current between P1 and P2 is I+, I+=Ic+Im, where Ic is the current flowing through the second electrode 225 between P1 and P2, and Im is the current flowing through the voltmeter 211.

[0040] 2) The voltage between P1 and P2 is U P1-P2 , U P1-P2 =Ic*Rc; U P1-P2 =Im*(Rm+2*(Rpad+Rvia+Rpath)), where Rm is the internal resistance of the voltmeter 211, Rpad is an anode resistance, Rvia is a resistance of a line-changing contact hole (refer to via 204 in Figure 3 ), and Rpath is a test trace resistance, wherein Rm is very large and greater than kΩ, Rm>> (Rpad+Rvia+Rpath); Therefore, U P1-P2 =Im*(Rm+2*(Rpad+Rvia+Rpath))≈Im*Rm=Um, where Um is the voltage measurement value of the voltmeter 211.

[0041] 3) Rc<<Rm, based on U P1-P2 =Ic*Rc≈Im*Rm, then Ic>>Im, that is, I+=Ic+Im≈Ic.

[0042] It can be known from this that Rc=U P1-P2 / Ic≈Um / I+, that is, Rc can be obtained by dividing the voltage measurement value Um of the voltmeter 211 by the first current signal I+.

[0043] Similarly, it can be concluded that Figure 8 This is a schematic diagram of a first light-emitting group provided in an embodiment of the present invention. For example... Figure 8 As shown, the first light-emitting group includes four first light-emitting devices 222 arranged sequentially along the F1 direction. The first electrodes 224 of the four first light-emitting devices 222 are respectively connected to test traces 221. A test module (not shown) is connected to the test traces 221. The test module includes a voltmeter 211. The test module provides a first current signal I+ to the first test trace 221 and a ground signal GND to the fourth test trace 221 to ground it. The voltmeter 211 is connected between the second and third test traces 221, and can measure the resistance value Rcaa between two adjacent first light-emitting devices 222 in the first light-emitting group. The current flowing through the resistance Rcaa between two adjacent first light-emitting devices 222 in the first light-emitting group is Icaa, and this resistance value can be selected as the first resistance parameter. Rcaa is equal to the voltage measurement value Umaa of the voltmeter divided by the first current signal I+.

[0044] If (Rcaa-Rc) / Rc>+5%, or (Rcaa-Rc) / Rc<-5%, it indicates that the first and second resistance parameters are significantly offset, meaning that the voltage drop distribution of the second electrode of the display panel is uneven, affecting the display effect.

[0045] -5%≤(Rcaa-Rc) / Rc≤+5% indicates that the deviation between the first and second resistance parameters is small, which means that the voltage drop distribution of the second electrode of the display panel is relatively uniform and the display uniformity is good.

[0046] It's understandable that panel manufacturing conditions can be adjusted. For example, to achieve a more uniform display panel, the manufacturing conditions can be adjusted to have an offset within the range of -0.5% to +0.5%. Relevant personnel can design panel manufacturing conditions appropriately based on product requirements.

[0047] In addition, the test module can also test the test results of multiple display panels. Relevant professionals can select the display panel with the smallest deviation from them. The test result of the display panel is the best, and the uniformity of the display panel is the best among all test samples. Mass production is then carried out based on the process parameters of the display panel.

[0048] In addition, the test module obtains the test results of the display panel. Relevant professionals can analyze the test structure of the display panel and adjust and optimize the process parameters of the display panel, such as adjusting the photolithography parameters of the pixel limiting layer, adjusting the film thickness of the cathode, adjusting the alloy ratio of the cathode alloy layer, etc. By adjusting the process parameters of the display panel and then testing, the display panel with the required offset can be obtained.

[0049] It should be noted that for the dummy light-emitting group, the resistance value Rc between two adjacent dummy light-emitting devices in the dummy light-emitting group is measured, and the sheet resistance of this resistance value can be selected as the second resistance parameter. Correspondingly, for the first light-emitting group, the resistance value Rcaa between two adjacent first light-emitting devices in the first light-emitting group is measured, and the sheet resistance of this resistance value can be selected as the first resistance parameter. If the aspect ratio of the resistance pattern between two adjacent dummy light-emitting devices in the dummy light-emitting group is designed as na:1, then the sheet resistance of Rc is Rc / na. If the aspect ratio of the resistance pattern between two adjacent first light-emitting devices in the first light-emitting group is designed as nb:1, then the sheet resistance of Rcaa is Rcaa / nb.

[0050] It is understandable that the ramp position of the pixel limiting layer of the dummy light-emitting device corresponds to the bottom-cut opening position of the first light-emitting device. The sheet resistance of the second electrode corresponding to the ramp position of the pixel limiting layer of the dummy light-emitting device can be regarded as its standard sheet resistance value Rc / na, which is generally small. Ideally, the sheet resistance Rcaa / nb of the second electrode corresponding to the bottom-cut opening position of the first light-emitting device should be close to Rc / na, and the smaller the offset between the two, the better the uniformity of the display panel. However, the bottom-cut opening depth of the overall display panel may be too large, resulting in an increase in Rcaa. In this case, the increase in Rcaa / nb and the increase in the offset from Rc / na, i.e., Rcaa / nb is greater than Rc / na, will cause the IR DROP (voltage drop) of the second electrode corresponding to the first light-emitting device to increase, thus affecting the display uniformity.

[0051] Based on this ((Rcaa / nb)-(Rc / na)) / (Rc / na)>+5%, or ((Rcaa / nb)-(Rc / na)) / (Rc / na)<-5%, it indicates that the deviation between the first and second resistance parameters is large, meaning that the voltage drop distribution of the second electrode of the display panel is uneven, affecting the display effect. -5%≤((Rcaa / nb)-(Rc / na)) / (Rc / na)≤+5%, it indicates that the deviation between the first and second resistance parameters is small, meaning that the voltage drop distribution of the second electrode of the display panel is relatively uniform, resulting in better display uniformity. It is understandable that panel manufacturing conditions can be adjusted, and relevant personnel can reasonably design panel manufacturing conditions according to product requirements. As mentioned above, by reasonably setting panel manufacturing conditions and testing the display panel, a display panel that meets the panel manufacturing conditions can be obtained. Then, its bottom-cut opening depth Tuc may satisfy: the light-emitting layer is disconnected, and the film thickness of the second electrode becomes thinner at the ramp position. In other words, mass production is carried out based on the process parameters of the display panel that meet the panel manufacturing conditions. Its second resistance parameter is close to the first resistance parameter, resulting in good display uniformity of the display panel and reducing the defect rate.

[0052] In this invention, the test module is connected to the display panel via test traces. It measures the second resistance parameter between dummy light-emitting devices and the first resistance parameter between first light-emitting devices. The second resistance parameter is used as the standard value for the resistance parameter between two adjacent light-emitting devices. The first and second resistance parameters can then be compared. If both meet the panel manufacturing conditions, the display panel has better uniformity and is suitable for mass production. Conversely, if they do not meet the panel manufacturing conditions, the display panel has poor uniformity and is not suitable for mass production. By reasonably setting the panel manufacturing conditions and testing the display panel, a display panel that meets the manufacturing conditions and whose process parameters are within a reasonable range can be obtained. Mass production of the panel based on the process parameters of the display panel that meets the manufacturing conditions will result in a close approximation of the second and first resistance parameters, leading to good display uniformity, improved production yield, and reduced defect rate.

[0053] At least one of two adjacent first light-emitting devices can be selected, and its first electrode includes a first sub-region and a second sub-region. The test module is connected to the first sub-region and the second sub-region respectively through two test lines. Two adjacent first light-emitting devices satisfy at least one of the following conditions: 1) The test module provides a first current signal to the first sub-region of the first light-emitting device; 2) The test module provides a grounding signal to the second sub-region of the second first light-emitting device; 3) The test module measures the first resistance parameter between the second sub-region of the first light-emitting device and the first sub-region of the second light-emitting device.

[0054] Figure 9 This is a schematic diagram of another first light-emitting group provided in an embodiment of the present invention. For example... Figure 9 As shown, the first light-emitting group includes three first light-emitting devices 222a~222c arranged sequentially along the F1 direction. The first electrodes 224 of the three first light-emitting devices 222 are respectively connected to test traces 221. Optionally, the first electrode 224 of the first light-emitting device 222a includes a first sub-region 224a and a second sub-region 224b arranged sequentially along the F1 direction. The test module is connected to the first sub-region 224a through test trace 221e, and to the second sub-region 224b through test trace 221f. The test module is connected to the first electrode 224 of the first light-emitting device 222b through test trace 221g, and to the first electrode 224 of the first light-emitting device 222c through test trace 221h.

[0055] For the first light-emitting group, the test module provides a first current signal I+ to the first sub-region 224a of the first light-emitting device 222a through test trace 221e, and provides a ground signal GND to ground it through test trace 221h. The voltmeter 211 is connected to the second sub-region 224b of the first light-emitting device 222a through test trace 221f, and to the first electrode 224 of the first light-emitting device 222b through test trace 221g. The resistance value Rcaa between the second sub-region 224b of the adjacent first light-emitting device 222a and the first light-emitting device 222b can be measured, where the current flowing through resistor Rcaa is Icaa. This resistance value can be selected as the first resistance parameter. Rcaa is equal to the voltage measurement value Umaa of the voltmeter 211 divided by the first current signal I+.

[0056] Figure 10 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention. Figure 9 The difference is that, Figure 10 The first electrode 224 of the optional first light-emitting device 222c includes a first sub-region 224a and a second sub-region 224b arranged sequentially along the F1 direction. The test module is connected to the first sub-region 224a through test trace 221g, and the test module is connected to the second sub-region 224b through test trace 221h. The test module is connected to the first electrode 224 of the first light-emitting device 222a through test trace 221e, and the test module is connected to the first electrode 224 of the first light-emitting device 222b through test trace 221f.

[0057] For the first light-emitting group, the test module provides a first current signal I+ to the first electrode 224 of the first light-emitting device 222a through test trace 221e, and provides a ground signal GND to the second sub-region 224b of the first light-emitting device 222c through test trace 221h, grounding it. The voltmeter 211 is connected to the first electrode 224 of the first light-emitting device 222b through test trace 221f and to the first sub-region 224a of the first light-emitting device 222c through test trace 221g. The resistance value Rcaa between adjacent first light-emitting devices 222b and the first sub-region 224a of the first light-emitting device 222c can be measured, where the current flowing through resistor Rcaa is Icaa. This resistance value can be selected as the first resistance parameter.

[0058] Figure 11 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention. Figure 9 and Figure 10 The difference lies in that the first light-emitting group includes two first light-emitting devices 222a~222b arranged sequentially along the F1 direction. Optionally, the first electrode 224 of the first light-emitting device 222a includes a first sub-region 224a and a second sub-region 224b arranged sequentially along the F1 direction. The test module connects to the first sub-region 224a via test trace 221e and to the second sub-region 224b via test trace 221f. Optionally, the first electrode 224 of the first light-emitting device 222b includes a first sub-region 224c and a second sub-region 224d arranged sequentially along the F1 direction. The test module connects to the first sub-region 224c via test trace 221g and to the second sub-region 224d via test trace 221h.

[0059] For the first light-emitting group, the test module provides a first current signal I+ to the first sub-region 224a of the first light-emitting device 222a through test trace 221e, and provides a ground signal GND to the second sub-region 224d of the first light-emitting device 222b through test trace 221h, grounding it. The voltmeter 211 is connected to the second sub-region 224b of the first light-emitting device 222a through test trace 221f and to the first sub-region 224c of the first light-emitting device 222b through test trace 221g. The resistance value Rcaa between adjacent second sub-regions 224b and 224c of the first light-emitting device 222a can be measured, where the current flowing through resistor Rcaa is Icaa. This resistance value can be selected as the first resistance parameter. Rcaa is equal to the voltage measurement value Umaa of the voltmeter 211 divided by the first current signal I+.

[0060] The optional first electrode includes a first sub-electrode and a second sub-electrode spaced apart, with the first sub-electrode serving as a first sub-region and the second sub-electrode serving as a second sub-region. The first and second sub-electrodes may be arranged along a first direction; or the second sub-electrode may surround the first sub-electrode; or the first sub-electrode may surround the second sub-electrode. In this embodiment, the reference numerals for the first sub-electrode and the first sub-region are reused, as are the reference numerals for the second sub-electrode and the second sub-region.

[0061] Figure 12 This is a schematic diagram of yet another first light-emitting group provided in an embodiment of the present invention. Figure 11 The difference is, such as Figure 12 As shown, the first sub-region 224a and the second sub-region 224b of the optional first light-emitting device 222a are alternately arranged, and the first sub-electrodes 224a and 224b in the first electrode 224 are arranged along the first direction F1. Alternatively, the first sub-region 224c and the second sub-region 224d of the optional first light-emitting device 222b are alternately arranged, and the first sub-electrodes 224c and 224d in the first electrode 224 are arranged along the first direction F1. However, it is understood that when the display panel is displaying, the first sub-electrodes and the second sub-electrodes in the first electrode receive the same signal. Its testing process is the same as... Figure 11 Similarly, this will not be repeated here. In other embodiments, one of two adjacent first light-emitting devices may have a first sub-region and a second sub-region disposed at an interval.

[0062] Figure 13 This is a schematic diagram of another first light-emitting group provided in an embodiment of the present invention. Figure 14 yes Figure 13 A schematic diagram of the first electrodes of two adjacent first light-emitting devices. Figure 12 The difference is, such as Figure 13 and Figure 14 As shown, the first sub-region 224a and the second sub-region 224b of the optional first light-emitting device 222a are alternately arranged, and the second sub-electrode 224b of the first electrode 224 surrounds the first sub-electrode 224a. Alternatively, the first sub-region 224c and the second sub-region 224d of the optional first light-emitting device 222b are alternately arranged, and the first sub-electrode 224c of the first electrode 224 surrounds the second sub-electrode 224d. However, it is understood that when the display panel is displaying, the first sub-electrode and the second sub-electrode of the first electrode receive the same signal. Its testing process is the same as... Figure 11 Similarly, this will not be repeated here. In other embodiments, one of two adjacent first light-emitting devices may have a first sub-region and a second sub-region disposed at an interval.

[0063] The optional first light-emitting group includes a first light-emitting device arranged along a first direction, two adjacent first light-emitting devices, and a second light-emitting device; the test module is used to provide a first current signal to the first light-emitting device and a ground signal to the second light-emitting device. Optionally, at least one of the first and second light-emitting devices may be a dummy light-emitting device.

[0064] Figure 15 This is a schematic diagram of another first light-emitting group provided in an embodiment of the present invention, as shown below. Figure 15 As shown, the optional first light-emitting group includes four light-emitting devices arranged along the F1 direction. These four light-emitting devices include one dummy light-emitting device 223 and three adjacent first light-emitting devices 222. Combined with... Figure 2 As shown, three adjacent first light-emitting devices 222 can be located in the same pixel row; dummy light-emitting device 223 and first light-emitting device 222 can be located in the same pixel row, or dummy light-emitting device 223 and first light-emitting device 222 can be located in different pixel rows. The first electrode 224 of the light-emitting device is connected to the test module through test trace 221. For the first light-emitting group, along the F1 direction, the dummy light-emitting device 223 can be located at the first position of the four light-emitting devices. For the first light-emitting group, the test module provides a first current signal I+ to the first electrode 224 of the dummy light-emitting device 223 located in the first position, and provides a ground signal GND to the first electrode 224 of the first light-emitting device 222 located in the last position. Then, the resistance value Rcaa between two adjacent first light-emitting devices 222 located in the middle is measured by voltmeter 211, where the current flowing through the resistor Rcaa is Icaa, and Rcaa is equal to the voltage measurement value Umaa of voltmeter 211 divided by the first current signal I+.

[0065] In other embodiments, for the first light-emitting group, along the F1 direction, the dummy light-emitting device can be located at the end of the four light-emitting devices. Then, the test module provides a first current signal to the first electrode of the first light-emitting device located in the first position, and the test module provides a ground signal to the first electrode of the dummy light-emitting device located at the end. The resistance value between the two adjacent first light-emitting devices located in the middle is tested by a voltmeter.

[0066] Figure 16 This is a schematic diagram of another first light-emitting group provided in an embodiment of the present invention, as shown below. Figure 16 As shown, the optional first light-emitting group includes four light-emitting devices arranged along the F1 direction. These four light-emitting devices include two dummy light-emitting devices 223 and two adjacent first light-emitting devices 222. The two dummy light-emitting devices 223 are located on either side of the two adjacent first light-emitting devices 222. (Combined with...) Figure 2As shown, two adjacent first light-emitting devices 222 can be located in the same pixel row; two dummy light-emitting devices 223 are spaced apart and can be located in the same pixel row or in different rows. For the first light-emitting group, along the F1 direction, the two dummy light-emitting devices 223 are located at the first and last positions of the four light-emitting devices, respectively. For the first light-emitting group, the test module provides a first current signal I+ to the first electrode 224 of the dummy light-emitting device 223 located in the first position and a ground signal GND to the first electrode 224 of the dummy light-emitting device 223 located in the last position. Then, the resistance value Rcaa between the two adjacent first light-emitting devices 222 located in the middle is measured by the voltmeter 211, where the current flowing through the resistor Rcaa is Icaa, and Rcaa is equal to the voltage measurement value Umaa of the voltmeter 211 divided by the first current signal I+.

[0067] As described in the above embodiments, the test module can measure the first resistance parameter and the second resistance parameter in various ways. Depending on the product requirements, the test module can also measure the first resistance parameter and the second resistance parameter in other ways, which will not be elaborated further. For example, the test module obtains the first resistance parameter only through two adjacent dummy light-emitting devices.

[0068] Based on the same inventive concept, embodiments of the present invention also provide a testing method for a display testing device, which is applied to the display testing device described in any of the above embodiments. The testing method is applicable to the testing of a display panel. The testing method can be executed by a testing device, which can be implemented in hardware and / or software. The testing device can be configured in the testing module described in any of the above embodiments.

[0069] Figure 17 This is a schematic diagram of a testing method for a display testing device provided in an embodiment of the present invention. Figure 17 As shown, the test method includes: Step 310: Measure the first resistance parameter between two adjacent first light-emitting devices in the first light-emitting group, and measure the second resistance parameter between two adjacent dummy light-emitting devices in the dummy light-emitting group; Step 320: If the first resistance parameter and the second resistance parameter are found to meet the panel manufacturing conditions, the corresponding display panel process parameters are determined as the target process parameters.

[0070] Optional panel manufacturing conditions include: -5%≤(R AA -R DA ) / R DA ≤+5%; Among them, R AA R is the first resistance parameter. DA This is the second resistance parameter; The first resistance parameter and the second resistance parameter are both resistance values, or the first resistance parameter and the second resistance parameter are both sheet resistance values.

[0071] The testing method provided in the embodiments of the present invention can be applied to the testing module provided in any embodiment of the present invention, and has the corresponding beneficial effects during the execution of the testing module.

[0072] Figure 18 This is a schematic diagram of a testing device provided in an embodiment of the present invention. This testing device can be used to perform the testing methods described in any of the above embodiments, and can be configured in the testing module described in any of the above embodiments. Figure 18 As shown, the testing apparatus includes: The measurement module 410 is used to measure the first resistance parameter between two adjacent first light-emitting devices in the first light-emitting group, and to measure the second resistance parameter between two adjacent dummy light-emitting devices in the dummy light-emitting group. The detection module 420 is used to determine the corresponding display panel process parameters as target process parameters if the first resistance parameter and the second resistance parameter are detected to meet the panel manufacturing conditions.

[0073] In this invention, the testing method and apparatus can be applied to the testing process of process parameters in mass production of panels. Specifically, the testing module measures the first resistance parameter between two adjacent first light-emitting devices in the first light-emitting group and the second resistance parameter between two adjacent dummy light-emitting devices in the dummy light-emitting group. If the first and second resistance parameters meet the panel manufacturing conditions, it indicates that the display panel has better uniformity and is suitable for mass production. The corresponding process parameters of the display panel are then determined as the target process parameters for mass production. Conversely, if the first and second resistance parameters do not meet the panel manufacturing conditions, it indicates that the display panel has poor uniformity and is not suitable for mass production. By reasonably setting the panel manufacturing conditions and testing the display panel, a display panel that meets the panel manufacturing conditions can be obtained, with its process parameters within a reasonable range. Mass production of the panel based on the process parameters of the display panel that meets the panel manufacturing conditions results in a second resistance parameter that is close to the first resistance parameter, indicating good display uniformity, which can improve production yield and reduce defect rate.

[0074] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A display testing device, characterized in that, include: Display panel and test module; The display panel includes multiple light-emitting devices and multiple test traces, wherein the multiple light-emitting devices include a first light-emitting device and a dummy light-emitting device; The first light-emitting device includes a first electrode, a second electrode, and a light-emitting layer located between the first electrode and the second electrode; the dummy light-emitting device includes the first electrode and the second electrode; the plurality of light-emitting devices include a first light-emitting group and a dummy light-emitting group, the first light-emitting group includes two adjacent first light-emitting devices arranged along a first direction, and the dummy light-emitting group includes two adjacent dummy light-emitting devices arranged along the first direction; The test module includes multiple signal terminals, and each signal terminal is connected to a test trace. The test module is connected to the first electrode of the first light-emitting group and the first electrode of the dummy light-emitting group through the test traces, and is used to measure the first resistance parameter between two adjacent first light-emitting devices and the second resistance parameter between two adjacent dummy light-emitting devices, and to detect whether the first resistance parameter and the second resistance parameter meet the panel manufacturing conditions. The panel manufacturing condition is that the offset between the first resistance parameter and the second resistance parameter is within a preset range.

2. The display testing device according to claim 1, characterized in that, At least one of the two adjacent first light-emitting devices has a first electrode comprising a first sub-region and a second sub-region, and the test module is connected to the first sub-region and the second sub-region respectively through two test traces; The two adjacent first light-emitting devices satisfy the following condition: 1) The test module provides a first current signal to the first sub-region of the first light-emitting device; 2) The test module provides a ground signal to the second sub-region of the second first light-emitting device; 3) The test module measures the first resistance parameter between the second sub-region of the first first light-emitting device and the first sub-region of the second first light-emitting device.

3. The display testing device according to claim 2, characterized in that, The first electrode includes a first sub-electrode and a second sub-electrode spaced apart, the first sub-electrode serving as the first sub-region and the second sub-electrode serving as the second sub-region.

4. The display testing device according to claim 3, characterized in that, The first sub-electrode and the second sub-electrode in the first electrode are arranged along the first direction; Alternatively, the second sub-electrode surrounds the first sub-electrode; Alternatively, the first sub-electrode may surround the second sub-electrode.

5. The display testing device according to claim 1, characterized in that, The first light-emitting group includes a first light-emitting device arranged along the first direction, two adjacent first light-emitting devices, and a second light-emitting device; The test module is used to provide a first current signal to the first light-emitting device and a ground signal to the second light-emitting device.

6. The display testing device according to claim 5, characterized in that, At least one of the first and second light-emitting devices is the dummy light-emitting device.

7. The display testing device according to claim 1, characterized in that, The panel manufacturing conditions include: -5% < (R AA - R DA ) / R DA ≤ +5%; wherein R AA is the first resistance parameter, R DA is the second resistance parameter; Both the first resistance parameter and the second resistance parameter are resistance values, or both the first resistance parameter and the second resistance parameter are sheet resistance values.

8. The display testing device according to claim 1, characterized in that, The display panel includes: Substrate; A first metal layer located on one side of the substrate, the first metal layer including the plurality of test traces; The pixel defining layer is located on the side of the first metal layer opposite to the substrate, and the plurality of light-emitting devices are also present. The pixel defining layer includes a plurality of pixel openings, and the light-emitting devices overlap with the pixel openings in a direction perpendicular to the substrate. The test trace is connected to the corresponding first electrode via a via.

9. A testing method for a display testing device, characterized in that, Applied to the display testing apparatus as described in any one of claims 1-8, the testing method includes: Measure the first resistance parameter between two adjacent first light-emitting devices in the first light-emitting group, and measure the second resistance parameter between two adjacent dummy light-emitting devices in the dummy light-emitting group; If the first resistance parameter and the second resistance parameter are found to meet the panel manufacturing conditions, the corresponding display panel process parameters are determined as the target process parameters.

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