JP2008032958A - Lighting inspection device and lighting inspection method for display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting inspection device for a display panel that can inspect the display performance of the display panel, especially color unevenness by removing an influence of a warp of the display panel as much as possible even when the display panel warps. <P>SOLUTION: A spacer 24 is provided so as to be disposed in a region corresponding to a predetermined region of a lower substrate 11, the predetermined region including an electrode part. A probe 32 has a surface part (a surface abutting on the electrode part) which can abut on only the predetermined region including the electrode part on a surface of the lower substrate 11. When the lower substrate 11 warps, a correction range of the warp becomes small even if the probe 32 presses the lower substrate 11 when abutting on the electrode part. Namely, the warp is difficult to correct. When color unevenness is detected, the color unevenness is highly likely to be caused by a failure of a liquid crystal panel 1. Namely, the liquid crystal display panel 1 can exhibit desired performance, and the color unevenness is less likely to be generated owing to correction of warp. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inspection apparatus and an inspection method used for inspection for detecting color unevenness and the like of a display panel, and in particular, a display panel lighting inspection apparatus and a lighting inspection for performing inspection by lighting the display panel Regarding the method.

  As a test signal output device in a lighting inspection device for inspecting a liquid crystal display panel, a drive signal generator for generating a test drive signal to be applied to an electrode terminal (for example, a scan electrode terminal or a signal electrode terminal) of the liquid crystal display panel; There is a probe that transmits a drive signal generated by the drive signal generator, and is configured to supply a drive signal to all the electrode terminals by bringing the probe into contact with the electrode terminals (for example, (See Patent Document 1). Such an inspection is called a full lighting inspection. Hereinafter, the full lighting test is simply referred to as a lighting test.

  Further, as described in Patent Document 2, a liquid crystal display panel to be inspected is placed on a stage, and in this state, the probe in the inspection signal output device is lowered with respect to the electrode terminals of the liquid crystal display panel. When the probe comes into contact with the electrode terminal of the liquid crystal display panel, a drive signal is supplied to the electrode terminal.

Japanese Patent Laying-Open No. 2004-144697 (paragraphs 0028-0029, FIG. 1) JP 2003-166901 A (paragraphs 0012-0015, FIG. 1)

  FIG. 5 and FIG. 6 are explanatory diagrams schematically showing how the liquid crystal display panel is inspected for lighting using the lighting inspection apparatus described in Patent Documents 1 and 2. FIG. FIG. 5B shows the liquid crystal display panel 1 and the lighting inspection device when the liquid crystal display panel 1 and the lighting inspection device are viewed with a viewpoint changed by 90 ° from the case where the liquid crystal display panel 1 and the lighting inspection device are viewed as shown in FIG. It is shown. That is, FIG. 5 (B) shows the liquid crystal display panel 1 and the lighting inspection device as viewed from the right side in FIG. 5 (A). FIG. 6A shows a state where the probe 34 in the inspection signal output device 33 is in contact with the electrode terminal provided on the lower substrate 11.

  The liquid crystal display panel 1 has a configuration in which a lower substrate 11 and an upper substrate 12 face each other, and liquid crystal is sealed between them. The lower substrate 11 has a portion that does not face the upper substrate 12. In this portion, a driving IC for applying a driving signal to the electrodes arranged on the liquid crystal display panel 1 is mounted by COG (Chip On Glass). However, the lighting inspection is performed before the driving IC is mounted.

  The liquid crystal display panel 1 is placed on stages 22 and 23 disposed on the stage 21. In the example shown in FIG. 5, the mounting position of the driving IC (specifically, the back surface of the mounting position) is located on the stage 23, and the opposite side of the driving IC mounting position in the liquid crystal display panel 1 is on the stage 22. The liquid crystal display panel 1 is placed so as to be positioned.

  The inspection signal output device 33 transmits a drive signal from the drive signal generation unit 31 to an electrode terminal provided on the lower substrate 11 and outputs a drive signal instead of the drive IC. And a probe 34 made of a conductive member. Then, in a state where the drive signal is output from the drive signal generation unit 31, the inspection signal output device 33 is lowered toward the electrode terminal provided on the lower substrate 11 by the lifting mechanism (not shown). As shown in FIG. 6A, when the probe 34 comes into contact with the electrode terminal provided on the lower substrate 11, the drive signal from the drive signal generation unit 31 is input to the electrode terminal.

  In the liquid crystal display panel 1, all the pixels of the liquid crystal display panel 1 are lit with the same brightness if no disconnection occurs in the electrodes. When there is an electrode in which a disconnection occurs, a pixel related to the electrode is not lit. Even if no disconnection occurs, all pixels do not have the same brightness as long as a defect that causes color unevenness (such as defective electrode formation) occurs. For example, when the liquid crystal display panel 1 is a panel in which a plurality of scanning electrodes and a plurality of signal electrodes are arranged in a matrix, the inspection signal output device 33 applies the same scanning signal to all the scanning electrodes. A voltage is applied, and the same voltage is applied as an on-voltage to all signal electrodes.

  When the liquid crystal display panel is manufactured, the liquid crystal display panel 1 may be warped. The amount of warpage (for example, in the liquid crystal display panel 1, the height of the most convex portion or the most concave portion in the warped portion when the end portion is used as a reference) is several μm (for example, 5 μm). . The warpage is caused by non-uniform pressure when thermocompression bonding the lower substrate 11 and the upper substrate 12 with a sealing material, non-uniform distribution of spacers interposed between the lower substrate 11 and the upper substrate 12, or the like. Arise. In a single liquid crystal display panel 1, when warping occurs at a plurality of locations, the amount of warping and the direction of warping are different. Further, even between the plurality of liquid crystal display panels 1, the amount of warping and the direction of warping are different.

  As shown in FIG. 6B, when the warping reaches the portion (electrode portion) where the electrode terminal is provided on the lower substrate 11, as shown in FIG. 5 and FIG. When a proper lighting inspection is performed, the warping may be corrected, that is, the lower substrate 11 may become flat, and a drive signal may be input to the electrode portion.

  In particular, when a lighting inspection is performed in which the probe 34 is brought into contact with the electrode portion by hand, the warp tends to be corrected by pressing the inspection signal output device 33. In addition, when the warp is generated as shown in FIG. 6B, the liquid crystal display panel 1 is easily bent in a direction in which the warp disappears when pressed from above, so that a predetermined mechanism can be used without intervention. Even when a lighting inspection is performed in which the probe 34 is automatically brought into contact with the electrode portion, the warp tends to be corrected.

  Even if the liquid crystal display panel 1 is slightly warped, there is often no problem in display performance. On the other hand, when the warpage in the liquid crystal display panel 1 that is stable in the warped state is corrected, the stable state is broken, and thus uneven color or the like is likely to occur. Then, if the color unevenness is detected when the lighting inspection is performed with the warp corrected, whether the color unevenness has occurred due to the malfunction of the liquid crystal display panel 1, or the liquid crystal display panel 1 itself is Although the desired performance can be exhibited, it cannot be determined whether the color unevenness has occurred due to the correction of the warp.

  Therefore, the present invention eliminates the influence as much as possible even if the display panel is warped, and the display performance of the display panel, particularly a display panel lighting inspection device capable of inspecting the presence or absence of color unevenness, and It aims at providing the lighting inspection method.

  A lighting inspection apparatus for a display panel according to the present invention is a lighting inspection apparatus for inspecting a lighting state of a display panel by applying a drive signal to an electrode part formed on a substrate of the display panel, and a holding part for holding the display panel And an inspection signal output device having a drive signal generation unit that outputs a drive signal, and the holding unit has a surface portion that can contact only a region corresponding to a predetermined region including the electrode portion on the back surface of the display panel. The inspection signal output device includes a spacer member, and the inspection signal output device is a member that transmits the drive signal output from the drive signal generation unit to the electrode unit, and can be contacted only with a predetermined region including the electrode unit on the surface of the display panel. It is characterized by including the signal transmission member which has.

  The signal transmission member is preferably formed of a non-silicon elastic member.

  The display panel lighting inspection method according to the present invention uses a holding unit for holding a display panel and an inspection signal output device having a drive signal generation unit for outputting a drive signal, and an electrode unit formed on a substrate of the display panel. A lighting inspection method for inspecting the lighting state of the display panel by supplying a driving signal to the holding portion, wherein the holding portion has a surface portion that can contact only a region corresponding to a predetermined region including the electrode portion on the back surface of the display panel A surface member that is provided with a spacer member and transmits the drive signal output from the drive signal generator to the inspection signal output device to the electrode unit, and can contact only a predetermined region including the electrode unit on the surface of the display panel The signal transmission member is provided, and with the surface portion of the spacer member as a reference, the surface portion of the signal transmission member is located at a position corresponding to the amount obtained by adding a predetermined amount of warpage to the plate thickness of the display panel. After setting the, characterized in that is brought into contact with the signal transmission member to the electrode part.

  According to the present invention, even if the display panel is warped, the display performance such as color unevenness of the display panel itself can be inspected without being affected by the warp.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is an explanatory view schematically showing a state in which a lighting inspection of a liquid crystal display panel is performed using the lighting inspection device according to the first embodiment of the present invention. In FIG. 1B, as shown in FIG. 1A, the liquid crystal display panel 1 and the lighting inspection device when the viewpoint is changed by 90 ° from the case where the liquid crystal display panel 1 and the lighting inspection device are viewed. It is shown.

  The liquid crystal display panel 1 has a configuration in which a lower substrate 11 and an upper substrate 12 face each other, and liquid crystal is sealed between them. The lower substrate 11 has a portion that does not face the upper substrate 12. In this portion, a driving IC for applying a driving signal to the electrodes disposed on the liquid crystal display panel 1 is mounted. In FIG. 1, the polarizing plate 13 provided on the back side of the lower substrate 11 (the side opposite to the side facing the upper substrate 12) and the front side of the upper substrate 12 (side facing the lower substrate 11). The polarizing plate 14 provided on the opposite side) is also shown.

  The liquid crystal display panel 1 is placed on a stage 22 disposed on the stage 21 and a spacer 24 provided on the stage 23. In the example shown in FIG. 1, the liquid crystal display panel 1 is placed so that the electrode portion is located on the spacer 24 and the opposite side of the electrode portion in the liquid crystal display panel 1 is located on the stage 22. The stages 21, 22, and 23 and the spacer 24 correspond to a holding portion that holds the liquid crystal display panel 1, and the spacer 24 can abut only on a region corresponding to a predetermined region including the electrode portion on the back surface of the liquid crystal display panel 1. This corresponds to a spacer member having a smooth surface portion (a contact surface with respect to the back surface of the electrode portion). Since the stages 21, 22, and 23 are formed so that the polarizing plate 13 does not come into contact with any member during inspection, the polarizing plate 13 is prevented from being damaged during inspection.

  The inspection signal output device 30 transmits a drive signal from the drive signal generation unit 31 to the electrode terminal provided on the lower substrate 11 and outputs a drive signal instead of the drive IC. And a probe (signal transmission member) 32 made of a conductive member. While the drive signal is output from the drive signal generator 31, the inspection signal output device 30 is lowered toward the electrode terminal provided on the lower substrate 11 by an elevating mechanism (not shown). When the probe 32 comes into contact with the electrode terminal provided on the lower substrate 11, the drive signal from the drive signal generation unit 31 is input to the electrode terminal.

  As an example, the probe 32 is formed of a non-silicon conductive elastic body (for example, a non-silicon conductive rubber). When the probe 32 made of a non-silicon type conductive elastic body is used, naturally, no silicon type material adheres to the electrode terminal. After the inspection, the driving IC is actually mounted on the mounting portion of the driving IC on the lower substrate 11. At this time, the driving IC is generally mounted via an anisotropic conductive film. When the silicon-based material is attached to the electrode terminal, the anisotropic conductive film is easily peeled off. However, in this embodiment, the possibility of peeling of the anisotropic conductive film is reduced.

  Then, by visually observing the liquid crystal display panel 1, or by imaging the display surface of the liquid crystal display panel 1 with an imaging device and displaying the image on the display device, or performing image processing on the imaging result. Thus, the occurrence of electrode disconnection or color unevenness is detected.

  FIG. 2 is a plan view showing an example of the periphery of the mounting portion of the driving IC on the surface of the lower substrate 11 (the surface facing the upper substrate 12). In the example shown in FIG. 2, a signal input terminal portion 42 is formed on one side of the mounting portion 41 of the driving IC. The signal input terminal unit 42 is a terminal unit for inputting an image signal or the like from the outside of the liquid crystal display panel 1. In addition, an electrode portion 43 including a large number of electrode terminals is provided on the other side of the mounting portion 41 of the driving IC. The electrode terminal is connected to an electrode disposed in the display unit of the liquid crystal display panel 1 and is driven by a driving IC (at the time of lighting inspection, a driving signal from the driving signal generating unit 31 of the inspection signal output device 30). Is supplied to the electrode.

  In this embodiment, the surface portion (upper surface of the spacer 24) is a region corresponding to a predetermined region including the electrode portion 43 in the lower substrate 11 (specifically, the back surface of the predetermined region including the electrode portion 43) in the lighting inspection. A spacer 24 is provided so that is positioned. The cross-sectional area of the spacer 24 is about the area of the electrode portion 43 (preferably slightly larger than the area of the electrode portion 43 with a margin). That is, it is preferable that the predetermined region including the electrode part 43 is slightly wider than the electrode part 43. As an example, a copper film having a thickness of 70 μm and a width of 20 mm was used as the spacer 24. Further, the probe 32 has a surface portion (contact surface with respect to the electrode portion 43) that can contact only a predetermined region including the electrode portion 43 on the surface of the lower substrate 11. The size of the predetermined area where the surface portion of the probe 32 abuts is substantially equal to the size of the predetermined area where the spacer 24 abuts.

  Here, consider a case where the lower substrate 11 is warped. Since the spacer 24 is located only in a region corresponding to the electrode portion 43 in the lower substrate 11, even if the lower substrate 11 is pressed when the probe 32 contacts the electrode portion 43, as shown in FIG. 5. Compared with the case where the stage 23 exists on the back side in a wide range of the lower substrate 11, the correction range of the warp becomes narrower. That is, it becomes difficult to correct the warpage.

  Therefore, when color unevenness is detected, it is highly possible that the color unevenness is caused by a malfunction of the liquid crystal display panel 1. That is, although the liquid crystal display panel 1 itself can exhibit desired performance, the possibility of uneven color due to the correction of the warp is reduced.

  Here, the integrated probe 32 has been described as an example. However, as shown in FIG. 3A, a probe having a plurality of portions 32A, 32B, and 32C may be used. The parts 32A and 32C supply, for example, a drive signal applied to the scan electrode to the electrode terminal, and the part 32B supplies, for example, a drive signal applied to the signal electrode to the electrode terminal. In that case, the driving IC is configured to output a driving signal applied to the scanning electrode and a driving signal applied to the signal electrode from one side. Further, as shown in FIG. 3B, a probe having a larger number of sites may be used.

  Further, as a driving IC, a driving signal applied to the scanning electrode from one side (long side) is supplied to the electrode terminal, and driving is applied to the scanning electrode from two sides (short side) orthogonal to the long side. The present invention can also be applied to the case where a device configured to supply a signal to an electrode terminal is used. In that case, the cross section of the probe 32 is formed in a U-shape.

(Embodiment 2)
In the first embodiment, the inspection signal output device 30 is configured to move in the vertical direction (vertical direction) by an elevating mechanism (not shown). However, when a moving mechanism that can move in the vertical direction and also in the horizontal direction is provided, a lighting test that can obtain further effects can be performed.

  For example, it is assumed that the warp amount α that allows the liquid crystal display panel 1 itself to exhibit desired performance is 5 μm at the maximum although warpage has occurred. In that case, with the surface portion of the spacer 24 as a reference, the inspection signal output device 30 so that the surface portion of the probe 32 (contact surface to the electrode portion 43) reaches the position of [plate thickness + α] of the lower substrate 11. Is lowered. Then, after setting the liquid crystal display panel on the stages 21 and 22 and the spacer 24, the inspection signal output device 30 is translated so that the surface portion of the probe 32 comes to a position corresponding to the electrode portion 43.

  Then, as shown in FIGS. 4A and 4B, if the amount of warpage of the liquid crystal display panel 1 is less than or equal to α, the surface portion of the probe 32 is moved to a position corresponding to the electrode portion. Then, the lighting inspection as described above is performed. However, when the amount of warpage exceeds α, the probe 32 is blocked by the side surface of the liquid crystal display panel 1 and cannot reach the position corresponding to the electrode portion. The surface portion of the probe 32 may be set at the position [plate thickness + α] of the lower substrate 11 with the surface portion of the spacer 24 as a reference, but this is a value having a margin with respect to [plate thickness + α]. It is preferable to set the inspection signal output device 30 at a position of β (α <β)].

  From the above, the inspection signal output device 30 is set so that the surface portion of the probe 32 reaches the position of [plate thickness + α] or [plate thickness + β] of the lower substrate 11 with the surface portion of the spacer 24 as a reference. By doing so, it is possible to detect the liquid crystal display panel 1 having a warp exceeding an allowable amount in the lighting inspection.

  In each of the above embodiments, the liquid crystal display panel is taken as an example of the display panel, but the present invention can also be applied when inspecting other display panels such as an organic EL panel.

  The present invention is suitably applied to an application for performing a lighting inspection to detect color unevenness of the display panel, and is particularly useful when performing a lighting inspection of a display panel that may be warped during manufacturing.

Explanatory drawing which shows typically a mode that a liquid crystal display panel is test | inspected using the lighting test | inspection apparatus of 1st Embodiment. The top view which shows an example of the periphery of the mounting part of driving IC. Explanatory drawing which shows the other example of a probe. Explanatory drawing for demonstrating 1st Embodiment. Explanatory drawing which shows typically a mode that a liquid crystal display panel is test | inspected using the conventional lighting test | inspection apparatus. Explanatory drawing which shows typically a mode that a liquid crystal display panel is test | inspected using the conventional lighting test | inspection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal display panel 11 Lower board | substrate 12 Upper board | substrate 13,14 Polarizing plate 21,22,23 Stage 24 Spacer 30 Inspection signal output device 31 Drive signal generation part 32 Probe 41 Mounting part 42 Signal input terminal part 43 Electrode part

Claims (3)

In a display panel lighting inspection device for inspecting the lighting state of the display panel by applying a drive signal to the electrode part formed on the substrate of the display panel,
A holding unit that holds the display panel, and an inspection signal output device that includes a drive signal generation unit that outputs a drive signal;
The holding portion includes a spacer member having a surface portion that can contact only a region corresponding to a predetermined region including the electrode portion on the back surface of the display panel;
The inspection signal output device is a member that transmits the drive signal output from the drive signal generation unit to the electrode unit, and has a surface part that can contact only a predetermined region including the electrode part on the surface of the display panel. A lighting inspection device comprising a transmission member. The lighting inspection device according to claim 1, wherein the signal transmission member is formed of a non-silicon elastic member. Lighting state of the display panel by applying a driving signal to the electrode part formed on the substrate of the display panel using a holding unit for holding the display panel and an inspection signal output device having a driving signal generating unit for outputting a driving signal In the display panel lighting inspection method for inspecting
The holding portion is provided with a spacer member having a surface portion that can contact only a region corresponding to a predetermined region including the electrode portion on the back surface of the display panel,
A signal that is a member that transmits the drive signal output by the drive signal generation unit to the electrode unit to the inspection signal output device, and that has a surface part that can contact only a predetermined region including the electrode part on the surface of the display panel. A transmission member,
After setting the inspection signal output device so that the surface portion of the signal transmission member is at a position corresponding to the amount obtained by adding a predetermined amount of warpage to the plate thickness of the display panel, with the surface portion of the spacer member as a reference, A display panel lighting inspection method, wherein the signal transmission member is brought into contact with an electrode portion.

Images