A pixel structure measuring device and method

Abstract

The application discloses a pixel structure measuring device and method. The pixel structure measuring device comprises a test element group, a disconnecting unit and an electrical measuring unit; the test element group is electrically connected with the source, the drain and the gate of a second thin film transistor in a pixel structure to be measured; the disconnecting unit is used for disconnecting the source of a third thin film transistor from a shared voltage dividing wire and disconnecting the drain of the third thin film transistor from the drain of the second thin film transistor; the electrical measuring unit is electrically connected with the test element group and is used for obtaining an electrical characteristic measurement value of the second thin film transistor according to a measurement signal of the test element group. The application can avoid the influence of the shared voltage dividing wire and the voltage dividing effect of the third thin film transistor on the second thin film transistor, let the signal collected by the test element group be the independent and real electrical signal of the second thin film transistor, and make the electrical signal of the second thin film transistor measured by the electrical measuring unit finally be real and accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a pixel structure measuring device and method. BACKGROUND

[0002] In order to improve the color cast phenomenon of LCD display panel, increase the viewing angle and improve the contrast, the 3TFT (three thin film transistors) technology is currently used, that is, three thin film transistors are arranged in a pixel structure to control the pixel electrode, wherein the first TFT is connected with the main area of the pixel unit, the second TFT is connected with the secondary area of the pixel, and the third TFT is connected with the drain of the second TFT.

[0003] The electrical characteristics of TFT have an important influence on the performance of LCD display panel, so it is necessary to measure the electrical characteristics of the three TFTs respectively during the production process. When the electrical characteristics of the second TFT are measured, since the drain of the second TFT is connected with the third TFT, the data measured by the second TFT is not the real electrical characteristics, which further affects the correct evaluation of the electrical characteristics of the pixel structure and the whole display panel. SUMMARY

[0004] Based on the deficiencies and shortcomings of the prior art, the purpose of the present application is to provide a pixel structure measuring device and method, which can effectively measure the real electrical characteristics of the pixel structure.

[0005] To achieve the above-mentioned purpose, the present application first provides a pixel structure measuring device, comprising:

[0006] A test element group is electrically connected with the source, drain and gate of the second thin film transistor in the pixel structure to be measured; the pixel structure further comprises a main pixel area, a secondary pixel area, a first thin film transistor and a third thin film transistor; the source and drain of the first thin film transistor are connected with a data line and a main pixel electrode of the main pixel area, respectively; the source and drain of the second thin film transistor are connected with a data line and a secondary pixel electrode of the secondary pixel area, respectively; the source and drain of the third thin film transistor are connected with a shared voltage dividing trace and the drain of the second thin film transistor, respectively;

[0007] A disconnecting unit is used to disconnect the source of the third thin film transistor from the shared voltage dividing trace, and disconnect the third thin film transistor from the drain of the second thin film transistor;

[0008] An electrical measuring unit is electrically connected with the test element group, and is used to obtain the electrical characteristic measurement value of the second thin film transistor according to the measurement signal of the test element group.

[0009] Optionally, the second thin film transistor is formed with a via hole, a metal trace is arranged in the via hole, and the third thin film transistor is connected with the drain of the second thin film transistor through the metal trace; and the disconnecting unit is configured to disconnect the metal trace in the via hole.

[0010] Optionally, the test element group comprises a first electrode, a second electrode and a third electrode; and during the measurement, the first electrode, the second electrode and the third electrode are electrically connected with the source, the drain and the gate of the second thin film transistor, respectively.

[0011] Optionally, the pixel structure further comprises a temperature adjusting unit configured to adjust the ambient temperature of the pixel structure to a range of 10-35 DEG C.

[0012] Optionally, the pixel structure further comprises a brightness adjusting unit configured to adjust the backlight brightness of a display panel on which the pixel structure is located to a range of 4000-5000 nits.

[0013] Optionally, the pixel structure further comprises a control unit communicatively connected with the disconnecting unit, the temperature adjusting unit and the brightness adjusting unit.

[0014] The application also provides a pixel structure measurement method, comprising:

[0015] providing a test element group, a disconnecting unit and an electrical measurement unit;

[0016] electrically connecting the test element group with the source, the drain and the gate of the second thin film transistor in the pixel structure to be measured; the pixel structure further comprises a main pixel area, a sub-pixel area, a first thin film transistor and a third thin film transistor; the source and the drain of the first thin film transistor are connected with a data line and a main pixel electrode of the main pixel area, respectively; the source and the drain of the second thin film transistor are connected with a data line and a sub-pixel electrode of the sub-pixel area, respectively; and the source and the drain of the third thin film transistor are connected with a shared voltage dividing trace and the drain of the second thin film transistor, respectively.

[0017] disconnecting the source of the third thin film transistor from the shared voltage dividing trace and disconnecting the third thin film transistor from the drain of the second thin film transistor through the disconnecting unit;

[0018] receiving a measurement signal of the test element group through the electrical measurement unit, and obtaining an electrical characteristic measurement value of the second thin film transistor according to the measurement signal.

[0019] Optionally, the second thin film transistor is formed with a via hole, a metal trace is arranged in the via hole, and the third thin film transistor is connected with the drain of the second thin film transistor through the metal trace; and the step of disconnecting the third thin film transistor from the drain of the second thin film transistor further comprises:

[0020] The metal trace in the via is disconnected by the disconnecting unit, so that the third thin film transistor is disconnected from the drain of the second thin film transistor.

[0021] Optionally, the step of electrically connecting the test element group to the source, drain and gate of the second thin film transistor in the pixel structure to be measured further comprises:

[0022] The ambient temperature of the pixel structure is controlled to be between 10 DEG C and 35 DEG C.

[0023] Optionally, the step of electrically connecting the test element group to the source, drain and gate of the second thin film transistor in the pixel structure to be measured further comprises:

[0024] The backlight brightness of the display panel in which the pixel structure is located is adjusted to be between 4000 nits and 5000 nits.

[0025] Compared with the prior art, the pixel structure measuring device has the following advantages: the pixel structure measuring device comprises a test element group, a disconnecting unit and an electrical measuring unit; the test element group is electrically connected to the source, drain and gate of the second thin film transistor in the pixel structure to be measured; the disconnecting unit is used for disconnecting the source of the third thin film transistor from the shared voltage dividing trace and disconnecting the drain of the third thin film transistor from the drain of the second thin film transistor; the electrical measuring unit is electrically connected to the test element group and is used for obtaining the electrical characteristic measurement value of the second thin film transistor according to the measurement signal of the test element group. The source of the third thin film transistor is disconnected from the shared voltage dividing trace, and the drain of the third thin film transistor is disconnected from the drain of the second thin film transistor, so that the second thin film transistor is not affected by the shared voltage dividing trace and the voltage dividing effect of the third thin film transistor, the signal collected by the test element group is the independent and true electrical signal of the second thin film transistor, and the electrical signal of the second thin film transistor measured by the electrical measuring unit is true and accurate. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only show some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without any creative effort.

[0027] Figure 1 is a plan view of the pixel structure of the embodiment of the present application;

[0028] Figure 2 is an architecture diagram of the pixel structure measuring device of the embodiment of the present application;

[0029] Figure 3is a schematic diagram of a cut position of a third thin film transistor of an embodiment of the present application;

[0030] Figure 4 is a structural schematic diagram of a test element group of an embodiment of the present application;

[0031] Figure 5 is a step flow chart of a pixel structure measurement method of an embodiment of the present application. DETAILED DESCRIPTION

[0032] The following description of the embodiments is provided as an example to illustrate the specific embodiments that the present application can be used to implement. In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms “mounting”, “connection”, “connecting” should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral connection; can be mechanical connection, can also be electrical connection or can communicate with each other; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication of two elements or interaction relationship between two elements. At the same time, the terms “first”, “second” in the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features with “first”, “second” can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of “multiple” is two or more, unless otherwise explicitly specified and limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0033] The embodiment of the present application provides a pixel structure measurement device for detecting the electrical characteristics of the pixel structure on the array substrate of the display panel. Wherein, the array substrate includes a bottom plate, pixel structures, data lines L1, scan lines (gate lines) and shared voltage division traces L2 (share bars) arranged in an array on the bottom plate.

[0034] Specifically, as Figure 1As shown, the pixel structure includes a main pixel region 1, a sub-pixel region 2, a first thin-film transistor T1, a second thin-film transistor T2, and a third thin-film transistor T3. The source T11 and drain T12 of the first thin-film transistor T1 are connected to the data line L1 and the main pixel electrode (not shown) of the main pixel region 1, respectively. The source T21 and drain T22 of the second thin-film transistor T2 are connected to the data line L1 and the sub-pixel electrode (not shown) of the sub-pixel region 2, respectively. The source T31 and drain T32 of the third thin-film transistor T3 are connected to the shared voltage divider line L2 and the drain T22 of the second thin-film transistor T2, respectively. The gates of the first thin-film transistor T1, the second thin-film transistor T2, and the third thin-film transistor T3 are interconnected and connected to the gate line (not shown). The drains of the second thin-film transistor T2 and the third thin-film transistor T3 are simultaneously connected to the sub-pixel electrode.

[0035] The first thin-film transistor T1 controls the charging and discharging of the main pixel area 1, the second thin-film transistor T2 controls the charging and discharging of the sub-pixel area 2, and the third thin-film transistor T3 pulls down the voltage of the sub-pixel area 2. During operation, the voltage on the scan line turns on the first thin-film transistor T1, the second thin-film transistor T2, and the third thin-film transistor T3. The shared voltage divider line L2 acts as a voltage divider, making the voltage of the sub-pixel area 2 lower than the voltage of the main pixel area 1. This results in a difference in brightness between the main pixel area 1 and the sub-pixel area 2, preventing the sub-pixel area 2 from becoming too bright and affecting the overall display effect.

[0036] Therefore, when measuring the electrical characteristics of the second thin-film transistor T2, the final measured value is not the true electrical characteristics of the second thin-film transistor T2 due to the influence of the third thin-film transistor T3 and the shared voltage divider line L2.

[0037] Based on this, such as Figure 2 As shown, the pixel structure measurement device in this embodiment includes a Test Element Group (TEG) 100, a disconnection unit 200, and an electrical measurement unit 300; wherein:

[0038] The test element group 100 is electrically connected to the source T21, drain and gate of the second thin film transistor T2 in the pixel structure to be measured;

[0039] The disconnection unit 200 is used to disconnect the source of the third thin-film transistor T3 from the shared voltage divider line L2, and to disconnect the drain T32 of the third thin-film transistor T3 from the drain T22 of the second thin-film transistor T2; wherein, as Figure 3As shown, the disconnection between the source T31 of the third thin film transistor T3 and the shared voltage dividing wire L2 is marked by a dashed line X1, and the disconnection between the drain T32 of the third thin film transistor T3 and the drain T22 of the second thin film transistor T2 is marked by a dashed line X2.

[0040] The electrical measurement unit 300 is electrically connected to the test element group 100, and is configured to obtain the electrical characteristic measurement value of the second thin film transistor T2 according to a measurement signal of the test element group 100.

[0041] In this embodiment, the pixel structure measurement device is used to disconnect the source T31 of the third thin film transistor T3 from the shared voltage dividing wire L2, and to disconnect the drain T32 of the third thin film transistor T3 from the drain T22 of the second thin film transistor T2, so as to avoid the second thin film transistor T2 being affected by the voltage dividing effect of the shared voltage dividing wire L2 and the third thin film transistor T3. The signal collected by the test element group 100 is the independent and true electrical signal of the second thin film transistor T2, and the electrical signal of the second thin film transistor T2 measured by the electrical measurement unit 300 is true and accurate.

[0042] In this embodiment, the electrical characteristic measurement value can be represented by an Id-Vg curve (transfer characteristic curve).

[0043] In this embodiment, the second thin film transistor T2 is formed with a via (not shown), and a metal wire M is arranged in the via. The third thin film transistor T3 is connected to the second thin film transistor T2 through the metal wire, and the disconnection unit 200 is configured to disconnect the metal wire M in the via. In this embodiment, the disconnection unit 200 can be a laser, which emits laser to disconnect the metal wire M in the via, and the metal wire connected between the third thin film transistor T3 and the shared voltage dividing wire L2 is also cut by the laser. In this way, the influence of the third thin film transistor T3 on the electrical measurement of the second thin film transistor T2 can be eliminated.

[0044] In this embodiment, as shown in FIG. 4, the disconnection unit 200 is arranged on the substrate 1, and is configured to disconnect the metal wire M in the via. Figure 4As shown, the test element group 100 includes a first electrode 101, a second electrode 102 and a third electrode 103; during measurement, the first electrode 101, the second electrode 102 and the third electrode 103 are electrically connected to the source T21, the drain T22 and the gate of the second thin film transistor T2 respectively. When measuring the thin film transistor, if the thin film transistor is directly measured by an electrical measuring device, there is a risk of damaging the thin film transistor. Therefore, in the embodiment, the test element group 100 is arranged on the non-display area of the array substrate, and the test element group 100 is also a thin film transistor, which has the same structure and electrical characteristics as the thin film transistor in the display area of the array substrate. In this way, the measurement of the thin film transistor in the pixel structure can be transferred to the test element group 100, avoiding the risk of damaging the thin film transistor during measurement.

[0045] In the embodiment, the pixel structure measuring device further includes a temperature adjusting unit 400, which is used to adjust the ambient temperature of the pixel structure to between 10°C and 35°C. The temperature adjusting unit 400 can be an air conditioner or a heat exchange device. Specifically, the ambient temperature can be adjusted to a conventional temperature, for example, about 25 degrees. The electrical characteristics of the pixel structure under normal temperature conditions are measured.

[0046] In the embodiment, the pixel structure measuring device further includes a brightness adjusting unit 500, which is used to adjust the backlight brightness of the display panel on which the pixel structure is located to between 4000 nits and 5000 nits. Specifically, the backlight brightness can be adjusted to 4200 nits, which is a backlight brightness interval during normal operation of the display panel, so as to measure the electrical characteristics of the pixel structure under conventional backlight brightness.

[0047] In the embodiment, the pixel structure measuring device further includes a control unit 600, which is in communication connection with the disconnecting unit 200, the temperature adjusting unit 400 and the brightness adjusting unit 500. The measurement temperature, backlight brightness and other parameters can be set in the control unit 600, so that the control unit 600 sends control instructions to the temperature adjusting unit 400 and the brightness adjusting unit 500 to adjust to the set ambient temperature and backlight brightness, and also sends working instructions to the disconnecting unit 200 to start or stop emitting laser. Through the control unit 600, automatic measurement can be realized, reducing the risk of errors caused by manual operation.

[0048] The embodiment of the present application provides a pixel structure measurement method, which is used for the pixel structure measurement device provided by the above embodiment, and the pixel structure to be measured comprises a main pixel area 1, a sub-pixel area 2, a first thin film transistor T1, a second thin film transistor T2 and a third thin film transistor T3; the source T11 and the drain T12 of the first thin film transistor T1 are connected with a data line L1 and a main pixel electrode (not shown) of the main pixel area 1 respectively; the source T21 and the drain T22 of the second thin film transistor T2 are connected with the data line L1 and a sub-pixel electrode (not shown) of the sub-pixel area 2 respectively; the source T31 and the drain T32 of the third thin film transistor T3 are connected with a shared voltage division wire L2 and the drain T22 of the second thin film transistor T2 respectively; the gate of the first thin film transistor T1, the gate of the second thin film transistor T2 and the gate of the third thin film transistor T3 are connected with each other and connected with a gate line (not shown), and the drains of the second thin film transistor T2 and the third thin film transistor T3 are connected with the sub-pixel electrode simultaneously.

[0049] As shown in the figure, the pixel structure measurement method comprises steps S1, S2, S3 and S4. Figure 5

[0050] Specifically, the following is:

[0051] In step S1, a test element group 100, a disconnecting unit 200 and an electrical measurement unit 300 are provided.

[0052] In step S2, the test element group 100 is electrically connected with the source T21, the drain and the gate of the second thin film transistor T2 in the pixel structure to be measured.

[0053] In step S3, the source T31 of the third thin film transistor T3 is disconnected from the shared voltage division wire L2, and the third thin film transistor T3 is disconnected from the drain T22 of the second thin film transistor T2 by the disconnecting unit 200.

[0054] In step S4, the measurement signal of the test element group 100 is received by the electrical measurement unit 300, and the electrical characteristic measurement value of the second thin film transistor T2 is obtained according to the measurement signal.

[0055] In the embodiment, the source T31 of the third thin film transistor T3 is disconnected from the shared voltage division wire L2, and the drain T32 of the third thin film transistor T3 is disconnected from the drain T22 of the second thin film transistor T2, so that the second thin film transistor T2 is not affected by the voltage division effect of the shared voltage division wire L2 and the third thin film transistor T3, the signal collected by the test element group 100 is the independent and true electrical signal of the second thin film transistor T2, and the electrical signal of the second thin film transistor T2 measured by the electrical measurement unit 300 is true and accurate.​

[0056] In the embodiment, the second thin film transistor T2 is formed with a via hole, and a metal trace M is arranged in the via hole, and the drain of the third thin film transistor T3 is connected to the drain of the second thin film transistor T2 through the metal trace M; the step of disconnecting the drain of the third thin film transistor T3 from the drain T22 of the second thin film transistor T2 further comprises:

[0057] The metal trace M in the via hole is disconnected by the disconnecting unit 200, so that the drain T32 of the third thin film transistor T3 is disconnected from the drain T22 of the second thin film transistor T2. In this way, the influence of the third thin film transistor T3 on the electrical measurement of the second thin film transistor T2 can be eliminated.

[0058] In the embodiment, the step of electrically connecting the test element group 100 to the source T21, the drain T22 and the gate of the second thin film transistor T2 in the pixel structure to be measured further comprises:

[0059] The ambient temperature of the pixel structure is controlled to be between 10 DEG C and 35 DEG C. Specifically, the ambient temperature can be controlled to be about 25 DEG C.

[0060] In the embodiment, the step of electrically connecting the test element group 100 to the source T21, the drain T22 and the gate of the second thin film transistor T2 in the pixel structure to be measured further comprises:

[0061] The backlight brightness of the display panel in which the pixel structure is located is adjusted to be between 4000 nits and 5000 nits. Specifically, the backlight brightness can be adjusted to be 4200 nits.

[0062] In the embodiment, the source T31 of the third thin film transistor T3 is disconnected from the shared voltage dividing trace L2, and the drain T32 of the third thin film transistor T3 is disconnected from the drain T22 of the second thin film transistor T2, so that the second thin film transistor T2 is not affected by the voltage dividing effect of the shared voltage dividing trace L2 and the third thin film transistor T3. The signal collected by the test element group 100 is the independent and true electrical signal of the second thin film transistor T2, and the electrical signal of the second thin film transistor T2 measured by the electrical measurement unit 300 is true and accurate.

[0063] The above description is only a preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any changes or replacements within the technical range disclosed by the present application can be easily thought of by those skilled in the art, and should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A pixel structure measuring apparatus characterized by comprising: The test element group is electrically connected with the source electrode, the drain electrode and the gate electrode of the second thin film transistor in the pixel structure to be measured; the pixel structure further comprises a main pixel area, a sub-pixel area, a first thin film transistor and a third thin film transistor; the source electrode and the drain electrode of the first thin film transistor are connected with a data line and a main pixel electrode of the main pixel area, respectively; the source electrode and the drain electrode of the second thin film transistor are connected with the data line and a sub-pixel electrode of the sub-pixel area, respectively; the source electrode and the drain electrode of the third thin film transistor are connected with a shared voltage dividing trace and the drain electrode of the second thin film transistor, respectively; the test element group comprises a first electrode, a second electrode and a third electrode, and during measurement, the first electrode, the second electrode and the third electrode are electrically connected with the source electrode, the drain electrode and the gate electrode of the second thin film transistor, respectively, and the first electrode, the second electrode and the third electrode constitute a thin film transistor; The disconnecting unit is used for disconnecting the source electrode of the third thin film transistor from the shared voltage dividing trace and disconnecting the third thin film transistor from the drain electrode of the second thin film transistor; The electrical measurement unit is electrically connected with the test element group and is used for obtaining an electrical characteristic measurement value of the second thin film transistor according to a measurement signal of the test element group. The second thin film transistor is formed with a via hole, a metal trace is arranged in the via hole, and the third thin film transistor is connected with the drain electrode of the second thin film transistor through the metal trace; the disconnecting unit is used for disconnecting the metal trace in the via hole.

2. The pixel structure measuring apparatus according to claim 1, characterized by The temperature adjusting unit is further used for adjusting an ambient temperature of the pixel structure to be between 10 DEG C and 35 DEG C.

3. The pixel structure measuring apparatus according to claim 1, wherein The brightness adjusting unit is further used for adjusting a backlight brightness of a display panel on which the pixel structure is located to be between 4000 nits and 5000 nits.

4. The pixel structure measuring apparatus according to claim 1, characterized by The control unit is in communication connection with the disconnecting unit, the temperature adjusting unit and the brightness adjusting unit, respectively.

5. The pixel structure measuring apparatus according to any one of claims 1 to 4, characterized by The test element group is electrically connected with the source electrode, the drain electrode and the gate electrode of the second thin film transistor in the pixel structure to be measured; the pixel structure further comprises a main pixel area, a sub-pixel area, a first thin film transistor and a third thin film transistor; the source electrode and the drain electrode of the first thin film transistor are connected with a data line and a main pixel electrode of the main pixel area, respectively; the source electrode and the drain electrode of the second thin film transistor are connected with the data line and a sub-pixel electrode of the sub-pixel area, respectively; the source electrode and the drain electrode of the third thin film transistor are connected with a shared voltage dividing trace and the drain electrode of the second thin film transistor, respectively; the test element group comprises a first electrode, a second electrode and a third electrode, and during measurement, the first electrode, the second electrode and the third electrode are electrically connected with the source electrode, the drain electrode and the gate electrode of the second thin film transistor, respectively, and the first electrode, the second electrode and the third electrode constitute a thin film transistor; 6. A pixel structure measurement method characterized by, ​ ​ ​ The third thin film transistor is disconnected from the drain of the second thin film transistor by the disconnecting unit; The electrical characteristic measurement value of the second thin film transistor is obtained according to the measurement signal received by the electrical measurement unit.

7. The pixel structure measurement method according to claim 6, wherein The second thin film transistor is formed with a via hole in which a metal trace is arranged, and the third thin film transistor is connected to the drain of the second thin film transistor through the metal trace; the step of disconnecting the third thin film transistor from the drain of the second thin film transistor further comprises: The metal trace in the via hole is disconnected by the disconnecting unit, so that the third thin film transistor is disconnected from the drain of the second thin film transistor.

8. The pixel structure measurement method according to claim 6, wherein The step of electrically connecting the test element group to the source, drain and gate of the second thin film transistor in the pixel structure to be measured further comprises: The ambient temperature of the pixel structure is controlled to be between 10 DEG C and 35 DEG C.

9. The pixel structure measurement method according to claim 6, wherein The step of electrically connecting the test element group to the source, drain and gate of the second thin film transistor in the pixel structure to be measured further comprises: The backlight brightness of the display panel in which the pixel structure is located is adjusted to between 4000 nits and 5000 nits.

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