JPH09258155A - Production of liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiency control the light transmittance in a liquid crystal display device to a desired light transmittance by forming the one spot of an energy ray to a specific or smaller spot diameter parting from another spot adjacent in a scanning direction. SOLUTION: A YAG laser is made incident on a counter substrate 301 side from an array substrate 301 in such a manner that its spot diameter (ϕ) of 3μm is focused just before the array substrate 201. The spot diameter (ϕa) on the oriented film 411 on the array substrate 201 side is 5μm and the spot diameter (ϕb) on the oriented film 413 on the counter substrate 301 side is 8μm. From the ends of pixel electrodes 251 to the other ends are scanned in parallel with the end sides of the pixel electrodes 251 along the longitudinal direction of the scanning lines and the scanning direction at the other end is turned back, by which the pixel electrodes are successively scanned and irradiated with the laser approximately in parallel. More specifically, the ends where the scanning is started is set at the positions apart respectively by 7μm in the distance from the opening end sides determined by light shielding layers 311.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid crystal display device, and more particularly to a method of manufacturing a liquid crystal display device which adjusts the light transmittance of display pixels to improve display quality.

[0002]

2. Description of the Related Art Liquid crystal display devices are widely used because of their features such as thinness, light weight and low power consumption. For example, it is used as a display device in various fields such as a computer, a car navigation system or a television display system.

In recent years, such a liquid crystal display device is particularly required to have a large display screen or a high definition, and a large screen display having a diagonal size of more than 14 inches or 100
Research and development such as those having a fine display pixel pitch of μm or less are under way.

[0004]

In a liquid crystal display device having a large screen or a high-definition display screen as described above, it goes without saying that a display pixel having a voltage-light transmittance characteristic different from that of a normal pixel in the display screen, that is, There is a problem that the ratio of defective pixels increases.

The occurrence rate of defective pixels has been reduced to some extent by devising the design or manufacturing process of the liquid crystal display device, but has not been completely eliminated.
For this reason, it has been proposed, for example, to provide a liquid crystal display device with redundancy. It is also considered to repair defective pixels by adding a repair function,
There is a problem that various defects cannot be dealt with and a sufficient repair rate cannot be obtained.

In particular, as a defect pixel mode that significantly impairs the display quality of a liquid crystal display device, there is a bright spot defect. This bright spot defect is caused by various causes. Here, the bright spot defect is a so-called normally-occurring structure which has a maximum light transmittance when the potential difference between a pair of electrodes sandwiching the liquid crystal composition is a potential equal to or lower than the threshold voltage of the liquid crystal layer.
In a white mode liquid crystal display device, it is a defective pixel in which the light transmittance does not decrease even if a potential difference is applied between a pair of electrodes. Further, when the potential difference between the pair of electrodes sandwiching the liquid crystal composition is equal to or lower than the threshold voltage of the liquid crystal layer as described above, the so-called normally
In a black mode liquid crystal display device, a defective pixel in which the light transmittance does not decrease even though the potential difference between the pair of electrodes is equal to or less than the threshold voltage of the liquid crystal layer is collectively referred to.

Such a bright spot defect is a fatal defect pixel which impairs the commercial value as a liquid crystal display device even if it exists even in one place in the display screen. Therefore, countermeasures against it are urgent.

As a method for dealing with the defective pixel mode represented by such a bright spot defect, there is a method proposed in JP-A-60-243635. This method is a method of collectively irradiating defective pixels with a laser beam to burn out the alignment film and the pixel electrode itself, thereby eliminating the alignment property with respect to the liquid crystal composition. Such a technique is intended to make the abnormal light transmittance observed as a defect of various defective pixels including a bright spot defect inconspicuous.

However, in the method of irradiating the alignment film and the pixel electrode itself with laser light by the method disclosed in Japanese Patent Laid-Open No. 60-243635, the effect of making the bright spot defect a dark spot is actually obtained. Wasn't as expected. In the method of irradiating the alignment film and the pixel electrode itself by collectively irradiating the laser light as described above, the alignment film and the pixel electrode themselves are uniformly removed over a large area, and the region where the alignment film and the pixel electrode themselves are removed. Unexpectedly, the effect on the liquid crystal molecules is small enough to control the alignment, and the surface becomes rather flat. Therefore, in the region where the alignment film and the pixel electrode itself are removed, the liquid crystal molecules constituting the liquid crystal layer are uniformly realigned,
It is considered that the linearly polarized incident light that has entered the liquid crystal layer in that region is elliptically polarized and causes light leakage.

Therefore, the applicant proposed in Japanese Patent Application No. 6-200403 a method of controlling the light transmittance in a bright spot defect or the like. This does not mean that the alignment film or the pixel electrode itself is uniformly removed over a large area, but the alignment surface in contact with the liquid crystal molecules is roughened to an appropriate degree of roughness, and the alignment film or the pixel electrode remaining in the alignment surface in contact with the liquid crystal molecules is roughened. The light transmittance is controlled by controlling a substantially random alignment state, a vertical alignment state, a horizontal alignment state, a scattering state in which small domains are formed, or a mixed phase state thereof along the alignment planes such as.

Under such circumstances, as a result of further sincerity research, the applicant further copes with various defective pixel modes such as a bright spot defect and can efficiently control the liquid crystal to a desired light transmittance. The present invention was found by finding a method for manufacturing a display device.

It is an object of the present invention to provide a method of manufacturing a liquid crystal display device capable of efficiently controlling a desired light transmittance for various defect pixel modes such as a bright spot defect.

[0013]

According to a first aspect of the invention, a first electrode substrate having at least a first electrode and a first alignment film formed on a first substrate, and at least a second substrate on the second substrate are provided. A second electrode substrate on which a second electrode and a second alignment film facing the first substrate are formed, and the second electrode substrate is held between the first electrode substrate and the second electrode substrate. A liquid crystal layer containing liquid crystal molecules arranged in a predetermined direction based on the orientation provided to the second alignment film, and transmitting light according to a potential difference between the first electrode and the second electrode. In the method for manufacturing a liquid crystal display device, which comprises a plurality of display pixels of which the rate is changed, and which comprises a light transmittance adjusting step of adjusting the light transmittance by irradiating one display pixel which should have a different light transmittance with an energy ray, The light transmissivity adjustment process causes energy to be applied to the one display pixel. For irradiating a line intermittently and scanning in a plurality of substantially parallel thin lines, wherein one spot of the energy beam on the first alignment film is separated from other spots adjacent in the scanning direction by at least 20 μm. The spot diameter is as follows, which is a method for manufacturing a liquid crystal display device.

According to a second aspect of the present invention, in the method of manufacturing a liquid crystal display device according to the first aspect, the diameter of the spot of the energy rays on the first alignment film is φa, and the irradiation pitch in the scanning direction is P. Then, (P-φ
a) is in the range of 2 to 30 μm, which is a method for manufacturing a liquid crystal display device.

According to a third aspect of the present invention, in the method of manufacturing the liquid crystal display device according to the first aspect, the diameter (φa) of the spot of the energy rays on the first alignment film is
A method for manufacturing a liquid crystal display device is characterized in that the thickness is in the range of 2 to 10 μm.

The invention described in claim 4 is the method for manufacturing a liquid crystal display device according to claim 1, wherein the energy rays are laser beams.

According to a fifth aspect of the present invention, in the method of manufacturing a liquid crystal display device according to the first aspect, the method includes a step of detecting a defective display pixel from among the plurality of display pixels. In the method for manufacturing a liquid crystal display device, the light transmittance adjusting step is performed.

According to a sixth aspect of the present invention, a first electrode substrate having at least a first electrode and a first alignment film formed on a first substrate, and at least a first electrode substrate facing the first substrate on the second substrate. And a second electrode substrate on which a second electrode and a second alignment film are formed, and held between the first electrode substrate and the second electrode substrate, and applied to the first alignment film and the second alignment film. A liquid crystal layer including liquid crystal molecules arranged in a predetermined direction based on the aligned orientation, and a light transmittance of which varies according to a potential difference between the first electrode and the second electrode. In the method for manufacturing a liquid crystal display device, which comprises a plurality of, including a light transmittance adjusting step of irradiating an energy ray to one display pixel which should have a different light transmittance, and adjusting the light transmittance, wherein the light transmittance adjusting step is , Intermittently irradiating the one display pixel with energy rays A plurality of substantially parallel fine lines are scanned, and one spot of the energy beam on the first alignment film has a spot diameter of at least 20 μm or less that separates it from the spots of other adjacent fine lines. And a method for manufacturing a liquid crystal display device.

According to a seventh aspect of the present invention, in the method of manufacturing a liquid crystal display device according to the sixth aspect, when the diameter of the spot of the energy rays on the first alignment film is φa and the fine line pitch is Q, (Q-φa) is in the range of 2 to 30 μm in the method of manufacturing a liquid crystal display device.

According to an eighth aspect of the present invention, in the method of manufacturing a liquid crystal display device according to the sixth aspect, the spot diameter (φa) of the energy ray on the first alignment film is
A method of manufacturing a liquid crystal display device is characterized in that the thickness is in the range of 2 to 10 μm.

The invention described in claim 9 is the method for manufacturing a liquid crystal display device according to claim 6, wherein the energy beam is a laser beam.

The invention described in claim 10 is claim 6
In the method for manufacturing a liquid crystal display device described above, including a step of detecting a defective display pixel from among the plurality of display pixels,
A method of manufacturing a liquid crystal display device is characterized in that the light transmittance adjusting step is performed on the defective display pixel.

In the method of burning the alignment film and the pixel electrode itself by simply irradiating the bright spot defect pixels with the laser light all at once,
The reason why sufficient dark dots are not achieved is as described above, and by roughening the alignment surface in contact with the liquid crystal molecules to an appropriate degree of roughness, the liquid crystal molecules in this region are not uniformly re-aligned. , A substantially random alignment state, a vertical alignment state, a horizontal alignment state, a scattering state in which small domains are formed, or a mixed phase state thereof along the alignment surface of the alignment film or the pixel electrode remaining on the alignment surface in contact with the liquid crystal molecules. Therefore, the light transmittance is successfully controlled.

In order to obtain such a liquid crystal display device, it is effective to scan the energy rays into a plurality of substantially parallel thin lines. This is because the above configuration can be obtained relatively easily by scanning the energy rays in the form of multiple parallel thin lines and by buffering the energy rays, and the trajectory of the energy ray irradiation is reflected in the display state. This is because the uniform control of the light transmittance can be achieved within one display pixel.

The characteristic feature of the present invention is that
The spot diameter is set to be at least 20 μm or less in which one spot of the energy beam is separated from another spot adjacent to the scanning direction or one spot is separated from the spot of another thin line adjacent to the one spot.

When scanning is performed by overlapping adjacent spots, the larger the overlap area, the better the alignment surface in contact with the liquid crystal molecules can be roughened, and the transmittance can be greatly changed. Time is needed. On the other hand, by setting the spot diameter to at least 20 μm or less and performing scanning so that adjacent spots do not overlap with each other, it can be seen that the transmittance can be largely changed in the same manner as when the spots are sufficiently overlapped with each other. (See FIG. 6).

Further, in particular, in the relation between the spot diameter (φa) of the energy ray and the irradiation pitch (P), (P-
φa) is controlled to fall within the range of 2 to 30 μm,
Or in relation to the fine wire pitch (Q) (Q-φ
It was found that a particular effect can be obtained by controlling a) so that it falls within the range of 2 to 30 μm.

The reason why the light transmittance can be controlled in the same manner as in the case where the energy ray spots are scanned so that the energy ray spots do not overlap is probably because the thermal and liquid crystal molecules are controlled. The film surface is directly roughened in the area irradiated with energy rays due to physical damage such as sudden flow, and the surface condition of the film surface is indirectly modified in the peripheral area. This is considered to be due to a substantially random alignment state, a vertical alignment state, a horizontal alignment state, a scattering state in which small domains are formed, or a mixed phase state of these.

Further, as in the present invention, the processing is performed by scanning so that one spot of the energy beam is separated from another spot adjacent in the scanning direction or one spot is separated from the spot of another thin line adjacent thereto. Not only the time is shortened, but probably the alignment state of the liquid crystal molecules is not only the surface roughness of the film surface but also a stable predetermined alignment state according to the modified surface state. It was confirmed that even if some variations in the intensity occur, the effect on the light transmittance is small, and thus high reproducibility can be obtained.

It is preferable to irradiate the energy beam by controlling the focal position so as to be located at a depth outside the array substrate and the counter substrate, and thereby the alignment film or the electrode itself is deadly burned and removed. Without the above, the above-mentioned moderate surface roughness and surface modification are effectively formed on the alignment surface in contact with the liquid crystal layer.

In particular, in the case of a liquid crystal display device including an optical filter having a plurality of regions having different light transmission wavelengths such as a color filter, the energy rays are irradiated so that the substrate side where the optical filter is not arranged has a focal point. Is desirable.

A laser beam is preferably used as the energy beam, and a YAG laser and an excimer laser can be used, but a YAG laser is preferable. And YA
As a G laser, about several kHz, preferably 1 to 2
A pulse laser having a frequency of about 1 kHz and a power of about 1 to 20 mW is preferably used. The pulse laser frequency of 1 to 2 kHz is to prevent mutual overlap by controlling the scanning speed and to enable scanning in a short time. If the power is too large, the alignment film itself will be removed uniformly. 1-10m because it may be
W is preferred.

The area of the spot of the energy ray on the alignment film is 1/25 or less of the area of one display pixel in order to secure an appropriate surface roughness and to leave an unirradiated portion of the energy ray. It is preferable that the spot diameter is set to about 2 to 10 μm.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION A method for manufacturing a liquid crystal display device according to the present invention will be described below in a normally white mode.
An example of a light transmissive liquid crystal display device having a diagonal display area of 5 inches will be described.

As shown in FIGS. 1 and 2, the liquid crystal display device 101 includes an array substrate 201 and a counter substrate 301.
The twisted nematic liquid crystal composition 421 is applied to the substrates 201 and 301 via the alignment films 411 and 413, respectively.
They are opposed to each other so that they can be twisted by 90 ° and are held by a sealant (not shown). Polarizing plates 431 and 433 are arranged on the outer surfaces of the substrates 201 and 301 so that their polarization axes are orthogonal to each other.

The array substrate 201 is a transparent glass substrate 2
00, 640 × 3 video signal lines 203 and 480 scanning lines 205 are arranged substantially orthogonal to each other. Pixel electrodes 251 are arranged near the intersections of the respective video signal lines 203 and the respective scanning lines 205 via the TFTs 221. The pixel electrode 251 is connected to the video signal line 203.
Is formed with a side of 80 μm and the side with the scanning line 205 is formed of 60 μm, and such pixel electrodes 25 are arranged at a pitch of 100 μm.

In the TFT 221, the scanning line 205 itself is used as a gate electrode, and an insulating film 213 formed by laminating silicon oxide and silicon nitride is arranged on the scanning line 205, and a-Si: H is formed on the insulating film 213. The film is arranged as a semiconductor film 215. Further, on the semiconductor film 215,
A channel protective film 217 self-aligned with the scan line 205 and formed using silicon nitride is arranged. The semiconductor film 215 is electrically connected to each pixel electrode 251 through the n + -type a-Si: H film arranged as the low resistance semiconductor film 219 and the source electrode 231. The semiconductor film 215 is the low resistance semiconductor film 219.
+ Type a-Si: H film and signal line 2 arranged as
03 is electrically connected to the signal line 203 via the drain electrode 204 extended from 03.

Further, an auxiliary capacitance line 261 arranged substantially parallel to the scanning line 205 and having a region overlapping with the pixel electrode 251 is provided, and the pixel electrode 251 and the auxiliary capacitance line 2 are provided.
An auxiliary capacitance (Cs) is formed by 61. The auxiliary capacitance line 261 is set to have substantially the same potential as the counter electrode 341.

The counter substrate 301 is a transparent glass substrate 30.
0, the TFT 221 formed on the array substrate 201.
In order to shield the gap between the video signal line 203 and the pixel electrode 251, and the gap between the scanning line 205 and the pixel electrode 251, from a laminated body of a matrix of chromium (Cr) oxide film and chromium (Cr). The light shielding layer 311 is formed.

In each lattice pattern of the light shielding layer 311, red (R), green (G), for realizing color display,
In such a normally white mode liquid crystal display device 101, color portions 321 each composed of three primary colors of blue (B) are provided, and a counter electrode 341 made of ITO is arranged through an organic protective film 331. Operation Figure 3
This will be described with reference to FIG.

As shown in FIG. 3A, the pixel electrode 251
When the potential difference between the counter electrode 341 and the counter electrode 341 is less than or equal to the threshold voltage of the liquid crystal layer to almost 0, the incident light is linearly polarized along the transmission axis of the polarizing plate 431, and the transmission axis of the polarizing plate 433 opposite to the incident light. As shown in FIG. 5, a white (bright) display is observed by rotating the liquid crystal layer 421 about 90 ° along the alignment direction of the liquid crystal molecules and emitting the light to the screen on the display side.

On the other hand, as shown in FIG. 6B, the potential difference between the pixel electrode 251 and the counter electrode 341 is the liquid crystal layer 421.
If it is sufficient to excite the liquid crystal molecules that make up the liquid crystal molecules, the liquid crystal molecules are aligned along the electric field. Therefore, the incident light is linearly polarized along the transmission axis of the polarizing plate 431, and the liquid crystal layer 421
Pass through. However, since the linearly polarized light that passes through the liquid crystal layer 421 is linearly polarized light that is substantially orthogonal to the light transmission axis of the polarizing plate 433, black (dark) display is observed.

In the normally white mode liquid crystal display device 101 as described above, a conductive foreign substance is present between the pixel electrode 251 and the counter electrode 341 during manufacture,
The pixel electrode 251 has substantially the same potential as the counter electrode 341, or the pixel electrode 251 and the auxiliary capacitance line 261 (see FIG. 2).
Is short-circuited due to a defect in the insulating film 203, and the pixel electrode 251 is close to the potential of the counter electrode 341 in the auxiliary capacitance line 26.
For example, the potential difference between the pixel electrode 251 and the counter electrode 341 may be a bright spot defect exhibiting a high light transmittance substantially equal to substantially 0 because the potential is the same as 1.

Therefore, in this embodiment, first, the bright spot defective pixel is detected as follows. That is, the liquid crystal display device 1
To the video signal line 203 of 01, for example, a voltage that is positively inverted to +5 V and −5 V with respect to the center voltage in each field period is applied, and to the counter electrode 341 and the auxiliary capacitance line 261.
A voltage of 5 V is applied and a scanning pulse is sequentially supplied to each scanning line 205 to display black (dark).

Next, any one of the periphery and center of the display screen
The display brightness of 00 display pixels is detected and the average value thereof is stored as a reference black level. After that, the display screen is sequentially scanned to detect a pixel having a display brightness of 30% or more from the reference black level, and the pixel is stored as the bright spot defect pixel.

The bright spot defective pixel thus detected was irradiated with a laser beam as an energy ray to control the light transmittance of the bright spot defective pixel. Hereinafter, an example of this light transmittance adjusting step will be described. AO YAG laser
After adjusting with the -Q switch to make pulsed output light with a high peak value, and further expanding this with a collimator,
The light was reflected by the dichroic mirror and focused on the object to be processed by the condensing lens system, and the bright spot defect pixel which is the object to be processed was scanned as follows. In each of the following experimental examples and comparative examples, the pixel electrode 251 and the auxiliary capacitance line 261 are short-circuited, and the pixel electrode 251 and the counter electrode 34 are
The light transmittance of a normal pixel when the potential difference from 1 is almost 0 is 1
If it is set to 00%, even if a potential difference of not less than the threshold voltage of the liquid crystal layer is applied between the pixel electrode 251 and the counter electrode 341, a light transmittance close to 100% is detected, which is the most severe defect mode. The light transmittance of each of the red (R) display pixel, the green (G) display pixel, and the blue (B) display pixel, which are point defect pixels, was controlled as follows.

(Specific Example 1) First, pulse cycle: 1 k
As shown in FIG. 4, a YAG laser of Hz and power: 6 mW is incident from the array substrate 201 side to the counter substrate 301 side so that the spot diameter (φ) of 3 μm is focused in front of the array substrate 201. Here, the laser light is emitted from the array substrate 201 side because the counter substrate 301 realizes color display in red (R), green (G), and blue (B).
The counter substrate 30 including the color portion 321 composed of the three primary colors
This is because if the laser is irradiated from the 1st side, the utilization efficiency of the laser light is lowered, and variation is caused for each color. The spot diameter (φa) on the alignment film 411 on the array substrate 201 side is 5 μm, and the alignment film 41 on the counter substrate 301 side.
The spot diameter (φb) on No. 3 was 8 μm.

Then, as shown in FIG. 5, from the end (point a in the figure) of the pixel electrode 251 to the other end (point b in the figure) along the longitudinal direction of the scanning line 205, the end side of the pixel electrode 251. The scanning direction was turned back at the other end (point b in the drawing), and the upper part of the drawing was scanned substantially in parallel and irradiated.

More specifically, the ends (point a in the figure) at which the scanning is started are positioned at a distance (L) of 7 μm from the edge of the opening determined by the light-shielding layer 311. Then, the point a in the drawing is set as the scanning start position, and scanning is performed at a pulse cycle and a scanning speed set so that the spots of the laser pulses do not overlap each other. That is, while the spot diameter (φa) is 5 μm, the irradiation pitch (P
1) is 15 μm, and (P−φa) is set to 10 μm.

After the first scan is performed in this way, the scanning direction is reversed at the folded end of the scan (point b in the figure),
A second scan that is substantially parallel to the first scan is performed. Also at the folded-back end (point b in the figure), the distance (L) from the edge of the opening determined by the light-shielding layer 311 is located at 7 μm. Also, the fine line pitch (P2) between the first scan and the second scan
Is 15 μm in which the spot of the laser pulse of the first scanning and the spot of the laser pulse of the second scanning do not overlap each other, and (Q−φa) is set to 10 μm.

Scanning by such a pulse laser was sequentially performed as shown in FIG. As a result, at least in the case of scanning with overlapping spots of laser pulses,
Even though it took about 30 seconds, in this example, it was very short, about 3 seconds.

The alignment film 411 thus treated,
In addition to the irregularities formed by laser irradiation, the surface of 413 has alignment films 411, 4 in the laser non-irradiated portion.
13 It was confirmed that the surface was modified.

Further, according to the verification by the present inventors, it was confirmed that this region is a mixed phase including a randomly oriented state and a state in which small domains are formed. And 65
A backlight having an illuminance of 00 [lx] is used as the array substrate 20.
The counter electrode voltage (Vcom) and the video signal voltage (Vsig) are selected so that the potential difference between the counter electrode 341 and the pixel electrode 251 is 0V, and the scan pulse (Vg ) Is applied for white (bright) display, and when the light transmittance of normal pixels is 100%,
A sufficient deduction was achieved within the range of at least 15% for each color pixel.

In addition, when the laser pulse spots were overlapped and scanned, an increase in transmittance was observed when operated for 200 hours in a dry environment at 85 ° C. The variation of the transmittance is 2% for the displayed pixels.
It was suppressed to below, and a stable score was achieved.

As described above, according to this embodiment, the adjacent scanning line or video signal line is broken by irradiating the bright spot defect with the pulse laser having a fine spot diameter of at least 20 μm or less. Without incident,
In a short time, it was possible to make a score with good yield.

In the above-mentioned embodiment, the reason why the laser beam is not irradiated near the opening end is that the metal material forming the light-shielding film 311 may be scattered to cause display failure.

Further, in the above-mentioned embodiment, the array substrate 2
Although the pulse laser is incident from the 01 side to the counter substrate 301 side so that the focal position is in front of the array substrate 201, even if the focal position is set outside the counter substrate 301, that is, at a position deeper than the counter substrate 301. good. On the contrary, a pulse laser is incident from the counter substrate 301 side to the array substrate 201 side so that the focus thereof is present in front of the counter substrate 301, or the focus position is outside the array substrate 201, that is, at a position deeper than the array substrate 201. It may be set to.

In the above-mentioned embodiments, the laser light was scanned linearly, but it is not always linear and may be wavy as long as they are substantially parallel to each other. In addition to scanning along the opening edge of each pixel, scanning may be performed along a diagonal line, but scanning is preferably performed along the long side of the pixel electrode in consideration of reduction in processing time.

In each of the above embodiments, the case of dealing with the dark spot of the bright spot defective pixel has been described as an example, but the present invention is also effective for other bright spot defect modes. . For example, abnormal operation of the TFT due to electrostatic breakdown or mixing of conductive metallic foreign matter, short circuit of electrodes and its wiring system due to damage of interlayer insulating film, missing or missing of pixel electrode, abnormal alignment, mixing of transparent conductive foreign matter. The present invention is also effective for defect display pixels other than the bright spot defect caused by the above reasons.

Further, in the above embodiments, the light transmission type liquid crystal display device has been described as an example, but the present invention can be applied to a reflection type liquid crystal display device. Further, the present invention is a liquid crystal display operating in a normally white mode in which a twisted nematic liquid crystal having a twist of about 90 ° as in the above-mentioned embodiment and a polarizing plate arranged so that the polarization axis directions thereof are orthogonal to each other are combined. Besides the device, almost 90
It is also applicable to a twisted nematic liquid crystal with a twist and a liquid crystal display device operating in a normally black mode in which the polarization axis directions of polarizing plates are parallel to each other.

In addition to the active matrix type liquid crystal display device having a TFT as a switching element for each display pixel as in the above-described embodiment, the present invention also has, for example, an active matrix type liquid crystal display device having an MIM element. The present invention can also be applied to a device or a simple matrix type liquid crystal display device in which electrode substrates provided with stripe-shaped electrodes are arranged orthogonally.

[0062]

As described above, according to the manufacturing method of the present invention, various defect pixel modes such as a bright spot defect are dealt with, and desired light transmittance is controlled in a short time and with a high yield. I was able to.

[Brief description of drawings]

FIG. 1 is a partial schematic front view of an array substrate of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a partial schematic cross-sectional view of the liquid crystal display device taken along the line AA ′ in FIG.

FIG. 3 is a diagram for explaining the operation of the liquid crystal display device according to the embodiment of the present invention.

FIG. 4 is a partial schematic cross-sectional view for explaining a light transmittance control step according to an embodiment of the present invention.

FIG. 5 is a partial schematic front view for explaining the light transmittance control step of the embodiment of the present invention.

FIG. 6 is a diagram showing the overlap length dependence of the light transmittance (%), where the vertical axis represents the light transmittance (%) in the light transmittance control step and the horizontal axis represents the overlap length of the pulse laser. is there.

[Explanation of symbols]

 101 ... Liquid crystal display device 201 ... Array substrate 301 ... Counter substrate

Claims (10)

[Claims] 1. A first electrode substrate having at least a first electrode and a first alignment film formed on a first substrate, and a second electrode and a second alignment at least facing the first substrate on the second substrate. A second electrode substrate on which a film is formed, and a second electrode substrate, which is held between the first electrode substrate and the second electrode substrate, and which is predetermined based on the orientation provided to the first alignment film and the second alignment film. A plurality of display pixels each having a liquid crystal layer including liquid crystal molecules aligned in a direction, the light transmittance of which varies according to a potential difference between the first electrode and the second electrode. In a method of manufacturing a liquid crystal display device, which includes a light transmittance adjusting step of irradiating an energy ray to one display pixel to be made different, and adjusting a light transmittance, the light transmittance adjusting step comprises: Irradiate intermittently with a plurality of parallel thin wires Of the liquid crystal display device, wherein one spot of the energy beam on the first alignment film has a spot diameter of at least 20 μm or less spaced from another spot adjacent in the scanning direction. Production method. 2. The method of manufacturing a liquid crystal display device according to claim 1, wherein when the diameter of the spot of the energy rays on the first alignment film is φa and the irradiation pitch in the scanning direction is P, (P−φa ) Is in the range of 2 to 30 μm. 3. The liquid crystal display device manufacturing method according to claim 1, wherein a diameter (φa) of a spot of the energy ray on the first alignment film is within a range of 2 to 10 μm. Manufacturing method of display device. 4. The method of manufacturing a liquid crystal display device according to claim 1, wherein the energy ray is a laser beam. 5. The method of manufacturing a liquid crystal display device according to claim 1, further comprising the step of detecting a defective display pixel from the plurality of display pixels, and the light transmittance adjusting step for the defective display pixel. A method for manufacturing a liquid crystal display device, which is characterized by carrying out. 6. A first electrode substrate having at least a first electrode and a first alignment film formed on a first substrate, and a second electrode and a second alignment at least facing the first substrate on the second substrate. A second electrode substrate on which a film is formed, and a second electrode substrate, which is held between the first electrode substrate and the second electrode substrate, and which is predetermined based on the orientation provided to the first alignment film and the second alignment film. A plurality of display pixels each having a liquid crystal layer including liquid crystal molecules aligned in a direction, the light transmittance of which varies according to a potential difference between the first electrode and the second electrode. In a method of manufacturing a liquid crystal display device, which includes a light transmittance adjusting step of irradiating an energy ray to one display pixel to be made different, and adjusting a light transmittance, the light transmittance adjusting step comprises: Irradiate intermittently with a plurality of parallel thin wires And a spot diameter of at least 20 μm in which one spot of the energy beam on the first alignment film is separated from a spot of another thin line adjacent to the first alignment film. Method. 7. The method of manufacturing a liquid crystal display device according to claim 6, wherein a diameter of a spot of the energy beam on the first alignment film is φa, and a fine line pitch is Q.
-Φa) is in the range of 2 to 30 μm. 8. The liquid crystal display device manufacturing method according to claim 6, wherein the diameter (φa) of the spot of the energy rays on the first alignment film is in the range of 2 to 10 μm. Manufacturing method of display device. 9. The method of manufacturing a liquid crystal display device according to claim 6, wherein the energy rays are laser beams. 10. The method of manufacturing a liquid crystal display device according to claim 6, including a step of detecting a defective display pixel from a plurality of the display pixels, and performing the light transmittance adjusting step for the defective display pixel. A method for manufacturing a liquid crystal display device, which is characterized by carrying out.