JPH06105274B2 - Electrode short circuit inspection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] A short circuit between electrodes of a strip electrode that is not short-circuited at every other common electrode cannot be inspected by a method of sweeping while abutting a probe. Therefore, a drive head that generates an induced current and a detection head that detects the induced current are used to enable detection of such a short circuit in the strip electrode.

[Industrial application field]

The present invention relates to manufacturing a display device such as a liquid crystal display panel, and more particularly to a method for inspecting a short circuit between electrodes on an electrode plate.

FIG. 2 shows an example of the structure of a liquid crystal display panel.

In the figure, a transparent strip electrode 12 is formed on the surface of a transparent glass plate 11.
Two substrates 1 formed by forming an alignment film 13 on which an alignment film 13 such as a polyimide resin film or polyvinyl alcohol is formed.
Are made to face each other so that the electrode is formed inside, and the peripheral edge is sealed with the sealing material 2, and the nematic liquid crystal 3 containing the liquid crystal molecules 31 in the space formed by the two substrates 1 and the sealing material 2. Is injecting.

In the densified liquid crystal display panel, the interval between the strip electrodes 12 formed on the surface of the glass plate 11 is extremely small, and etching residue or small metal powder adheres between the strip electrodes 12. Then, there is a problem in that a short circuit occurs between the electrodes and the display quality of the display device is significantly impaired. Therefore, it is desired to realize an inspection method capable of easily detecting such a short circuit between the strip electrodes.

[Conventional technology]

 FIG. 3 is a diagram showing a conventional inspection method.

When inspecting the inter-electrode short circuit of the strip electrodes 12 formed on the surface of the glass plate 11 in FIG. 3 (a), one end of each strip electrode 12 is short-circuited by the common electrode 14 every other one.
The common electrode 14 is connected to a measuring device 4 such as an oscilloscope via a probe 41 that is brought into contact with the common electrode 14. While the other probe 42 connected to the measuring instrument 4 is brought into contact with the strip electrode 12, the glass plate 11 is swept from one end to the other end so that the signal shown in FIG. It is input to the measuring device 4.

That is, when the probe 42 that sweeps from one end to the other end of the glass plate 11 comes into contact with the strip electrode 12A that is short-circuited by the common electrode 14 that is in contact with the probe 41, through the strip electrode 12A and the common electrode 14. Probe 41 and probe 4
Shorted between two. Further, since the strip electrode 12B is not short-circuited by the common electrode 14, if there is no inter-electrode short circuit between the strip electrode 12A or the strip electrode 12C short-circuited by the common electrode 14, the probe 42 to be swept has the strip electrode adjacent thereto. When moving to 12B, the probe 41 and the probe 42 are not short-circuited via the strip electrode 12B. However, if there is an inter-electrode short circuit between the strip electrode 12B and the strip electrode 12A or the strip electrode 12C, the probe 41 and the probe 42 are short-circuited via the short-circuited portion of the strip electrode 12B.

[Problems to be solved by the invention]

When configuring a liquid crystal display panel and connecting it to a drive circuit, it is often the case that all of the strip electrodes 12 formed on the surface of the same glass plate 11 are short-circuited by a common electrode. However, in the conventional inspection method, in order to detect a short circuit between electrodes, it is necessary to short-circuit every other one end of the strip electrode with the common electrode. Further, although the inspection can be performed when the surface of the strip electrode is exposed, there is a problem that the inspection cannot be performed when the surface is covered with an insulating layer such as an alignment film.

[Means for Solving Problems] FIG. 1 is a principle diagram showing an inspection method according to the present invention. Note that the same object is denoted by the same symbol throughout the drawings.

The above problem is caused by the drive head 5 including the annular iron core 52 having the opening 51 and the coil 53 wound around the annular iron core 52.
And an annular iron core 62 having an opening 61, and a detection head 6 including a coil 63 wound around the annular iron core 62, and at least two strip electrodes 12A and 12B are formed in parallel to each other. In the inspection of No. 1, the drive head 5 is arranged on the electrode plate 1 via the insulating layer 7 to generate an induced current in the one strip electrode 12A located in the middle of the opening 51, and at the same time via the insulating layer 7. This is solved by the inter-electrode short-circuit inspection method of the present invention in which the detection head 6 is disposed on the electrode plate 1 and the induced current is detected from the other strip electrode 12B located in the middle of the opening 61.

[Action]

In FIG. 1, the driving head 5 and the detection head 6 are connected to the electrode plate 1.
One strip-shaped electrode disposed above and located in the middle of the opening 51
By generating an induced current in 12A and detecting the induced current from the other strip-shaped electrode 12B located in the middle of the opening 61, if there is an inter-electrode short circuit between the strip-shaped electrode 12A and the strip-shaped electrode 12B, the strip-shaped The induced current generated in the electrode 12A flows to the strip electrode 12B via the short-circuited portion, and the induced current detected by the detection head 6 is amplified and input to a measuring instrument such as an oscilloscope.

According to the inspection method of the present invention based on such a principle,
It is not necessary to short-circuit every other end of the strip electrode with the common electrode for inspection. Even if the surface of the strip electrode is covered with an insulating layer, a short circuit between electrodes can be inspected.

〔Example〕

 An embodiment of the present invention will be described below with reference to FIG.

In the figure, the drive head 5 is an annular iron core 52 having an opening 51.
And a coil 53 wound around it, and a high frequency current output from an oscillator 81 is applied to the coil 53. The detection head 6 comprises an annular iron core 62 having an opening 61 and a coil 63 wound around the iron core 62, and a measuring instrument 83 such as an oscilloscope is connected to the coil 63 via an amplifier 82.

The electrode plate 1 constituting the liquid crystal display panel is a transparent glass plate 11
And a strip electrode 12 formed parallel to the surface of the glass plate 11, and one end of the strip electrode 12 is short-circuited by a common electrode 14. When inspecting an electrode short circuit between the two strip electrodes 12A and 12B, the drive head 5 is disposed on the electrode plate 1 through the insulating layer 7, and one strip electrode positioned in the middle of the opening 51 is provided. Generate an induced current at 12A. Further, the detection head 6 is disposed on the electrode plate 1 via the insulating layer 7, and the induced current is detected from the other strip electrode 12B located in the middle of the opening 61.

That is, in the figure, if there is no inter-electrode short circuit 12D between the strip electrodes 12A and 12B, the circuit composed of the strip electrodes 12A, the common electrode 14, and the strip electrodes 12B is placed on the electrode plate 1 in an open state. Even if a high-frequency current is applied to the coil 53 of the drive head 5, one of the strip electrodes 12 located in the middle of the opening 51
No induced current is generated in A.

However, an electrode-to-electrode short circuit 12 occurs between the strip electrodes 12A and 12B.
With D, strip electrode 12A, common electrode 14, and strip electrode
The circuit composed of 12B is closed by a short circuit between electrodes 12D, and when a high-frequency current is applied to the coil 53 of the drive head 5 arranged on the electrode plate 1, induction is made to one of the strip electrodes 12A located in the middle of the opening 51. Electric current is generated. The induced current flows to the strip electrode 12B via the inter-electrode short circuit 12D as shown by the broken line in the figure, and the induced current detected by the detection head 6 is amplified and input to a measuring instrument such as an oscilloscope.

Further, by sequentially moving the positions of the driving head 5 and the detection head 6 arranged on the electrode plate 1, for all the band-shaped electrodes 12 formed on the electrode plate 1, electrodes between adjacent band-shaped electrodes are formed. It is possible to detect an inter-circuit short circuit.

As described above, according to the inspection method of the present invention, it is not necessary to short-circuit every other one end of the strip electrode with the common electrode for the inspection. Even if the surface of the strip electrode is covered with an insulating layer, a short circuit between electrodes can be inspected.

〔The invention's effect〕

As described above, according to the present invention, there is provided an inter-electrode short circuit inspection method that does not require shorting every other electrode with a common electrode for inspection, and can perform inspection even if the surface is covered with an insulating layer. be able to.

[Brief description of drawings]

 FIG. 1 is a principle diagram showing an inspection method according to the present invention, FIG. 2 is a configuration example of a liquid crystal display panel, and FIG. 3 is a diagram showing a conventional inspection method. In the figure, 1 is an electrode plate, 5 is a driving head, 6 is a detection head, 7 is an insulating layer, 11 is a glass plate, 12, 12A and 12B are strip electrodes, 12D is a short circuit between electrodes, 14 is a common electrode, 51 and 61. Is an opening, 52 and 62 are annular iron cores, 53 and 63 are coils, 81 is an oscillator, 82 is an amplifier, and 83 is a measuring instrument.

Claims (2)

[Claims] 1. A drive head (5) comprising an annular iron core (52) having an opening (51) and a coil (53) wound around the annular iron core (52), and an opening (61). At least two strip-shaped electrodes (12A, 12B) are arranged in parallel by using a detection head (6) including a ring-shaped iron core (62) having a coil and a coil (63) wound around the ring-shaped iron core (62). When inspecting the formed electrode plate (1), the drive head (5) is disposed on the electrode plate (1) through an insulating layer (7),
One of the strip electrodes (12) located in the middle of the opening (51)
In addition to generating an induced current in (A), the detection head (6) is disposed on the electrode plate (1) through the insulating layer (7), and the other one located in the middle of the opening (61). An inter-electrode short-circuit inspection method characterized by detecting an induced current from the strip electrode (12B). 2. The entire strip electrodes (12) formed on the electrode plate (1) by sequentially moving the positions of a driving head (5) and a detection head (6) arranged on the electrode plate (1). The short-circuit inspection method between electrodes of Claim 1 which inspects the short circuit between electrodes.