JP2008015073A - Method for correcting defect of color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for correcting a defect without causing clogging at an ejection port by using irradiation light from a light source for transmission illumination and a light source for reflection illumination when correction using a UV curing type correction liquid and a micro dispenser is carried out. <P>SOLUTION: Correction is made by using the UV curing type correction liquid and the micro dispenser 22 and using a halogen lamp as the light source 11 for transmission illumination and the light source 13 for reflection illumination while always irradiating the ejection port 21 with the irradiation light from the light source for transmission illumination and irradiating the ejection port with the irradiation light from the light source for reflection illumination at the time of correction. At that time, UV ray absorption filters 1A, 1B and IR ray absorption filters 2A, 2B are provided to the light source for transmission illumination and the light source for reflection illumination to prevent photocuring of the correction liquid staying at the ejection port. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to color filter defect correction, and in particular, a color filter defect correction method capable of correcting a defect without causing clogging of a discharge port when performing correction using a microdispenser. About.

In a display device, it is a useful means to use a color filter for purposes such as color display, reflectance reduction, contrast improvement, and spectral characteristic control.
In many cases, the color filter used in the display device is formed as a pixel. A photolithography method is widely used as a method of forming pixels of a color filter used in this display device.

FIG. 5 is a plan view schematically showing an example of a color filter used in the liquid crystal display device. FIG. 6 is a cross-sectional view taken along the line XX ′ of the color filter shown in FIG.
As shown in FIGS. 5 and 6, in the color filter used in the liquid crystal display device, a black matrix (41), a colored pixel (42), and a transparent conductive film (43) are sequentially formed on a glass substrate (40). It has been done.
5 and 6 schematically show a color filter, and 12 colored pixels (42) are represented. In an actual color filter, for example, several hundreds of pixels are displayed on a 17-inch diagonal screen. A large number of colored pixels of about μm are arranged.

As a method of manufacturing a color filter having the above structure, which is used in many liquid crystal display devices, first, a black matrix is formed on a glass substrate, and then a colored pixel is aligned with this black matrix pattern. A method of forming a transparent conductive film and aligning a transparent conductive film is widely used.
The black matrix (41) is a matrix having light shielding properties, the colored pixels (42) have, for example, red, green, and blue filter functions, and the transparent conductive film (43) is transparent. Provided as a simple electrode.

  The black matrix (41) is composed of a matrix portion (41A) between the colored pixels (42) and a frame portion (41B) surrounding the peripheral portion of the region (display portion) where the colored pixels (42) are formed. Yes. The black matrix determines the position of the colored pixels of the color filter, makes the size uniform, and shields unwanted light when used in a display device, making the image of the display device uniform and uniform. In addition, it has a function of making an image with improved contrast.

  The black matrix is formed on the glass substrate by, for example, providing a coating film on the glass substrate (40) using a black photoresist for forming a black matrix, and exposing and developing the coating film to form a black matrix (41). ) Is used.

In addition, the colored pixel (42) is formed by providing a coating film on a glass substrate on which the black matrix is formed using, for example, a negative coloring photoresist in which a pigment or other pigment is dispersed. A method of forming colored pixels by exposure to light and development is used. In addition, the transparent conductive film (43) is formed on a glass substrate on which a black matrix and colored pixels are formed by, for example, forming a transparent conductive film by sputtering using ITO (Indium Tin Oxide). ing.
That is, a color filter used in a liquid crystal display device shown as an example is formed as a pixel (pattern) by a photolithography method except for a transparent conductive film.

When the black matrix (41) or the colored pixel (42) is formed, the pixel (pattern) may be defective. The pixel (pattern) defect is mainly classified into a white defect in which a part of the pixel is missing and a black defect due to adhesion of foreign matter.
The white defect is, for example, a missing portion of a pixel, that is, a pinhole caused by flipping of the photoresist on the surface of the glass substrate, bubbles in the photoresist, peeling of the film accompanying the removal of foreign matter on the pixel, or the like. When a color filter having a pinhole is incorporated in a liquid crystal display device, it is viewed as a white spot, which impairs display quality.

In addition, black defects are particles that are generated in the process, dust that is floating in the work place, and the like, and often become protrusions on the pixel. If the height of the projection is high enough to come into contact with the counter substrate of the liquid crystal display device, a short circuit is caused and display quality is impaired.
Accordingly, correction is applied to pixel (pattern) defects such as white defects and black defects generated when the black matrix (41) or the colored pixels (42) are formed.

1A to 1D are explanatory diagrams of an example of a method for correcting a white defect (pinhole). This correction method is a correction method for correcting a white defect by applying a correction liquid to a white defect portion using a correction needle.
FIG. 1A shows a state in which white defects (D1) are generated in the colored pixels (42) when the black matrix (41) and the colored pixels (42) are sequentially formed on the glass substrate (40). It is a representation. The size (a × b) of the colored pixel (42) is about 300 μm × 100 μm, and the film thickness is about 1.0 μm. The white defect (D1) having a size (c) of about 20 μm to 70 μm is to be corrected.

  FIG. 1B shows a stage in which the correction opening (S1) is formed in the white defect (D1) portion of the colored pixel (42). Since the planar shape of the white defect (D1) is indeterminate, a simple shape, for example, a square shape around the white defect (D1) as shown in FIG. This is one in which colored pixels are removed. For removal of the colored pixels, for example, the portion is volatilized using a laser.

FIG. 1C shows a stage where the correction port (S1) in the colored pixel (42) has been corrected and the correction film (45) has been formed. Moreover, FIG.1 (d) is sectional drawing in the XX line in FIG.1 (c). For the correction opening (S1), the correction liquid is attached to the tip of the correction needle, and the correction liquid is deposited on the correction opening (S1), that is, the glass substrate surface exposed from the correction opening (S1).
The coating of the correction liquid on the glass substrate surface is cured by, for example, UV irradiation or heat treatment in accordance with the composition of the correction liquid to form a correction film (45) to correct white defects (pinholes). Complete.

However, in the method for correcting a white defect using such a correction needle, as shown in FIGS. 1C and 1D, it is necessary to perform correction around the corrected correction port (S1). The correction liquid may be deposited on the normal coloring pixels (42) that are not present, and a protrusion (44) made of the correction liquid may be formed around the correction port (S1).
When the correction opening (S1) is increased, the size (g) of the projection (44) is increased in accordance with this size, and the colored pixel (42) has a color unevenness of the size (g) of the projection (44). It will be watched.

Therefore, in order to avoid color unevenness caused by such correction, there is a problem that the size (c) of the white defect (D1) to be corrected is naturally restricted. Further, when a color filter having protrusions (44) formed around the correction opening (S1) is used in a liquid crystal display device, the protrusions may hinder the alignment of liquid crystals.
Alternatively, if the height of the protrusion is high enough to be in contact with the counter substrate of the liquid crystal display device, there is a problem that a short circuit occurs and display quality is impaired.

  Although the above describes the method for correcting the white defect (D1) using the correction needle, the method for correcting the black defect is the same. In the case of a black defect, a black defect (not shown) and surrounding colored pixels are volatilized by a laser, a correction port having a simple shape is provided, and a correction liquid is applied and cured.

On the other hand, as for a correction method that solves the problems in the pixel defect correction method using the correction needle described above and a correction liquid, for example, JP 2004-67777 A uses a dispenser instead of the correction needle. A method for correcting a defect is disclosed.
This correction method is a correction method in which a correction liquid is filled in a glass dispenser, the correction liquid is discharged by pressurization with air, and the correction liquid is deposited on the correction port. A small dispenser called a microdispenser having a main body inner diameter of about 1 mmφ and a tip discharge port inner diameter of about 5 to 10 μmφ is used, but is characterized in that the amount of correction liquid discharged from the tip discharge port can be adjusted.

  For example, if the volume of the correction port (S1) is 1.5 μm for the color pixel and the area of the correction port (S1) is 50 μm □, the volume of the correction port (S1) is about 4 pl. It is in the range of 400 pl / sec and can be precisely adjusted.

By using such a micro-dispenser that can precisely adjust the discharge amount of the correction liquid, there is a problem when the correction needle is used, for example, on a normal colored pixel (42) that does not need to be corrected. The problem that the correction liquid is applied and color unevenness is observed is solved.
Thereby, it is possible to correct the larger white defect (D1) than before, and the size of the white defect (D1) to be corrected is enlarged.

In addition, the problem of using the correction needle, for example, the problem that the protrusion (44) by the correction liquid is formed around the correction port (S1) and the liquid crystal alignment is hindered is solved.
In addition, the correction method using the microdispenser requires a shorter time than the correction method using the correction needle, so that when there are a plurality of white defects in one color filter, or adjacent colored pixels Even when there are white defects straddling, the corresponding time required for correction is shortened.

  FIG. 2 is an explanatory diagram showing an outline of an example of a color filter defect correcting apparatus using a microdispenser. As shown in FIG. 2, the defect correcting apparatus includes a stage (10), a transmission illumination light source (11), an objective lens (12), a reflected illumination light source (13), an observation camera (14), and a curing light source. (15), a trimming light source (16), and a coating mechanism (20). A color filter (30) to be corrected is placed on the stage (10).

An example of a procedure for correcting a defect of a color filter using this defect correction apparatus is as follows. First, a defective portion is guided into the field of view of the observation camera (14) by an XY coordinate positioning mechanism (not shown). Irradiation light (L2) from the vertical illumination from the reflected illumination light source (13) is irradiated onto the defect portion from above, and the position of the defect portion on the optical axis is determined using a monitor screen attached to the observation camera (14). Set it accurately. For example, a halogen lamp is used as the reflected illumination light source (13).

Next, irradiation light (L4) from the light source for trimming (16) is applied to the defective portion from above, and a correction opening is formed in the defective portion and its peripheral portion (see FIG. 1B).
Since the planar shape of the defective portion is indefinite, it is made a simple shape, for example, a square, for easy correction. In addition, this correction port intentionally increases the area (volume) of the correction port in consideration of the discharge amount of the microdispenser.
As the trimming light source (16), for example, a second harmonic of a YAG laser is used.

Next, the irradiation light (L2) from the reflected illumination light source (13) is irradiated to the correction port, and the correction is made from the discharge port at the tip of the microdispenser while observing the monitor screen imaged by the observation camera (14). The liquid is discharged to the correction port and the correction liquid is applied.
Subsequently, the irradiation light (L3) from the curing light source (15) is applied to the coating from above to cure the coating and complete the correction. As the curing light source (15), for example, an ultra-high pressure mercury lamp is used when the correction liquid is an ultraviolet curing correction liquid.

3 and 4 are explanatory views showing, in an enlarged manner, portions of the objective lens (12) and the coating mechanism (20) of the defect correcting apparatus shown in FIG. As shown in FIGS. 3 and 4, the coating mechanism (20) includes a micro dispenser (22) and a four-axis moving means (23), for example, a rectangular coordinate robot.
FIG. 3 shows a state in which the microdispenser (22) is waiting at the standby position. FIG. 4 shows a state in which the discharge port (21) at the tip of the microdispenser (22) is close to the correction port and is in a correction position for discharging correction liquid to the correction port. The microdispenser (22) is moved between the standby position and the correction position by the four-axis moving means (23).

The correction work for applying the correction liquid to the correction port is performed by observing the monitor screen by positioning the discharge port (21) of the microdispenser (22) directly below the objective lens (12), that is, immediately above the correction port. While doing.
Thus, the discharge can be finely adjusted while observing the position of the discharge port (21) and the behavior of the correction liquid, and a precise and accurate correction operation can be performed.

However, in such a correction method, when the correction liquid is an ultraviolet curable correction liquid, the discharge port (21) of the microdispenser (22) is likely to be clogged, and the correction work is hindered. is there.
This is because during the correction work such as the position adjustment of the discharge port (21) and the discharge of the correction liquid while finely adjusting the discharge, as shown in FIG. 4, the irradiation light (L2) from the light source for reflection illumination (13) ) Irradiates the discharge port (21) of the micro-dispenser (22) directly under the objective lens (12). Therefore, the correction liquid starts to be photocured by photopolymerization and the fluidity is deteriorated.
Finally, the discharge port is clogged, and the correction liquid cannot be discharged even if the pressure is increased.

As shown in FIG. 2, a transmission illumination light source (11) is provided below the stage (10) on which the color filter (30) is placed. This transmitted illumination light source (11) is for observing the entire color filter (30) placed on the stage (10), and is always lit during the correction work. For example, a halogen lamp is often used as the light source for transmission illumination (11).
Therefore, as shown in FIG. 4, not only when the microdispenser (22) is in the correction position, but also when the microdispenser (22) is in the standby position as shown in FIG. Receives irradiation light (L1) of the transmission illumination light source (11) from below.

That is, the clogging of the discharge port (21) of the microdispenser (22) is promoted by the irradiation light (L1) from the light source for transmission illumination (11).
JP 2004-67777 A JP 2006-7126 A JP 2006-13343 A

  The present invention has been made to solve the above-described problem, and in correcting pixel (pattern) defects such as white defects and black defects of a color filter in which a black matrix and colored pixels are sequentially formed on a glass substrate. When using a UV curable correction liquid as the correction liquid and using a micro-dispenser as a jig for discharging the correction liquid, irradiation light from the transmitted illumination light source and reflected illumination light source of the defect correction apparatus Accordingly, it is an object of the present invention to provide a color filter defect correcting method capable of correcting color filter defects without causing clogging of the discharge port of the microdispenser.

The present invention relates to a defect correction method for a color filter in which a black matrix and colored pixels are formed on a glass substrate.
1) Use UV curable correction liquid as correction liquid,
2) A micro-dispenser is used as a jig for discharging the correction liquid to the correction port.
3) A halogen lamp is used as a light source for transmitted illumination for observing the color filter by transmitted illumination.
4) A halogen lamp is used as a light source for reflected illumination for observing the correction port on the color filter by epi-illumination.
5) While always irradiating the light emitted from the light source for transmitted illumination to the discharge port of the color filter and the microdispenser, the light emitted from the light source for reflected illumination is corrected and immediately above the correction port. When making corrections by applying correction liquid to the correction port while irradiating the discharge port of the micro dispenser,
The light source for transmitted illumination and the light source for reflected illumination are provided with an ultraviolet absorption filter and an infrared absorption filter to prevent photocuring of the correction liquid staying at the discharge port of the microdispenser, and the correction port without causing clogging of the discharge port The color filter defect correction method is characterized in that correction is performed by applying a correction liquid to the color filter.

  According to the present invention, in the defect correction method for a color filter according to the present invention, a means for measuring the irradiation time of the irradiation light from the light source for transmitted illumination is provided, and when the irradiation time reaches a preset time. A defect correction method for a color filter, wherein the light source for transmitted illumination is turned off.

The present invention uses 1) a UV curable correction solution, 2) a microdispenser, 3) a halogen lamp as a light source for transmitted illumination for observing the color filter by transmitted illumination, and 4) on the color filter. A halogen lamp is used as a light source for reflection illumination for observing the correction opening of the light source. 5) While always irradiating light emitted from the light source for transmission illumination to the discharge port of the color filter and the microdispenser, and for reflection illumination. When irradiating light from the light source to the correction port and the discharge port of the micro-dispenser immediately above the correction port at the time of correction, the correction light is applied to the correction port and correction is performed. A defect correction device is provided with an ultraviolet absorption filter and an infrared absorption filter in the light source for preventing the photocuring of the correction liquid staying at the discharge port of the microdispenser. With irradiated light from the transmitted illumination light source and reflected illumination light source, without clogging the discharge port of the microdispenser, the defect correction method for a color filter which can correct the defect of the color filter.

Hereinafter, the present invention will be described in detail based on embodiments.
FIG. 7 is an explanatory diagram showing an outline of an example of a color filter defect correcting apparatus used in the color filter defect correcting method according to the present invention. As shown in FIG. 7, the defect correcting apparatus includes a stage (10), a transmission illumination light source (11), an ultraviolet absorption filter (1A), an infrared absorption filter (2A), an objective lens (12), and a reflected illumination light source. (13), an ultraviolet absorption filter (1B), an infrared absorption filter (2B), an observation camera (14), a curing light source (15), a trimming light source (16), and a coating mechanism (20). . A color filter (30) to be corrected is placed on the stage (10).

  A halogen lamp is used as the light source for transmitted illumination (11). A halogen lamp is used as the reflected illumination light source (13). In contrast to the color filter defect correcting apparatus shown in FIG. 2, in the defect correcting apparatus shown in FIG. 7, an ultraviolet absorbing filter (1A) and an infrared absorbing filter are provided between the transmitted illumination light source (11) and the stage (10). (2A) is provided, and an ultraviolet absorption filter (1B) and an infrared absorption filter (2B) are provided between the reflection illumination light source (13) and the objective lens (12).

  Accordingly, the irradiation light (L1 ′) that has passed through the ultraviolet absorption filter (1A) and the infrared absorption filter (2A) from the transmission illumination light source (11) is an irradiation light from which the ultraviolet component and infrared rays have been cut. Similarly, the irradiation light (L2 ′) that has passed through the ultraviolet absorption filter (1B) and the infrared absorption filter (2B) from the reflected illumination light source (13) is an irradiation light from which the ultraviolet component and infrared rays have been cut. ing.

  Thereby, in the defect correction method of the color filter according to the present invention, in the defect correction, the ultraviolet curable correction liquid is used as the correction liquid, and the micro dispenser is used as the jig for discharging the correction liquid. However, the defect of the color filter can be corrected without causing clogging of the discharge port of the microdispenser by the irradiation light from the light source for transmitted illumination and the light source for reflected illumination of the defect correcting device.

  In order to obtain such an effect, it is easily considered to use, for example, a yellow lamp as a light source instead of the ultraviolet absorption filter. However, when a yellow lamp is used as a light source, when the colored pixels and the coating film of the correction liquid are observed, the yellow color of the yellow lamp affects the colored pixels and the coating film of the correction liquid, and the correction work is viewed in different hues. This is not preferable because it causes troubles.

  The ultraviolet absorption characteristics required for the ultraviolet absorption filter (1A) and the ultraviolet absorption filter (1B) vary depending on the spectral intensity of the halogen lamp and the color sensitivity of the ultraviolet curable correction liquid, but generally absorb wavelengths of 440 nm or less. I just want to be able to do it. At this time, the visible region of 440 nm or less is absorbed, but there is no large hue fluctuation as in the yellow lamp, and if this is the case, the correction work is not hindered.

In the present invention, although the ultraviolet light absorption filter (1A) is provided in the transmitted illumination light source (11), in order to further prevent photocuring of the correction liquid, the invention according to claim 2 When the set time is reached, the light source for transmission illumination (11) is turned off. This preset time is, for example, about 30 seconds.

  Examples of the transmission illumination light source (11) in the present invention include PDL-T-XXXX (model number) manufactured by Nippon P.I. Co., Ltd., and halogen lamps used for the transmission illumination light source (11) include, for example, Ushio. Electric Co., Ltd. product: JCR15V150WB (product number) is mentioned. The reflective illumination light source (13) is, for example, manufactured by Moritex Corporation: MHF-D-100LR-516 (model number), and the halogen lamp used for the reflective illumination light source (13) is, for example, Moritex Corporation. ) Product: LM-100 (product number).

Moreover, as an ultraviolet absorption filter (1A) provided in the light source for transmitted illumination (11), for example, Melles Grio Co., Ltd. product: 03FCG063 (product number) is used. Product: 43p (product number) is mentioned.
Moreover, as an ultraviolet absorption filter (2A) provided in the light source for reflected illumination (13), for example, Meles Griot Co., Ltd. product: 03FCG063 (product number), for example, as an infrared absorption filter (2B), manufactured by Moritex Co., Ltd. : FM-150 (product number).

(A)-(d) is explanatory drawing of an example of the method of correcting a white defect (pinhole). It is explanatory drawing which shows the outline of an example of the defect correction apparatus of the color filter using a micro dispenser. It is explanatory drawing showing the state which the microdispenser is waiting in a standby position. It is explanatory drawing showing the state which the discharge port of the front-end | tip of a microdispenser is in the correction position which approaches a correction port and discharges correction liquid to a correction port. It is the top view which showed typically an example of the color filter used for a liquid crystal display device. It is sectional drawing in the X-X 'line | wire of the color filter shown in FIG. It is explanatory drawing which shows the outline of an example of the defect correction apparatus of the color filter used in the defect correction method of the color filter by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1A, 1B ... Ultraviolet absorption filter 2A, 2B ... Ultraviolet absorption filter 10 ... Stage 11 ... Light source for transmitted illumination 12 ... Objective lens 13 ... Light source for reflected illumination 14 ... Observation Camera 15 ... Curing light source 16 ... Trimming light source 20 ... Coating mechanism 21 ... Discharge port 22 at the tip of the micro dispenser ... Micro dispenser 23 ... 4-axis moving means 30 ... -Color filter 40 ... Glass substrate 41 ... Black matrix 42 ... Colored pixel 43 ... Transparent conductive film 44 ... Projection 45 ... Correction film D1 ... White defect L1 ... Transmission Irradiation light L2 from the illumination light source ... Irradiation light L3 from the reflection illumination light source L3 ... Irradiation light L4 from the curing light source ... Irradiation light L1 'from the trimming light source ... Transmission light source from Irradiation light L2 'that has passed through the ultraviolet absorption filter and infrared absorption filter ... Irradiation light S1 that has passed through the ultraviolet absorption filter and infrared absorption filter from the reflected illumination light source ... Correction port

Claims (2)

In a defect correction method for a color filter in which a black matrix and colored pixels are formed on a glass substrate,
1) Use UV curable correction liquid as correction liquid,
2) A micro-dispenser is used as a jig for discharging the correction liquid to the correction port.
3) A halogen lamp is used as a light source for transmitted illumination for observing the color filter by transmitted illumination.
4) A halogen lamp is used as a light source for reflected illumination for observing the correction port on the color filter by epi-illumination.
5) While always irradiating the light emitted from the light source for transmitted illumination to the discharge port of the color filter and the microdispenser, the light emitted from the light source for reflected illumination is corrected and immediately above the correction port. When making corrections by applying correction liquid to the correction port while irradiating the discharge port of the micro dispenser,
The light source for transmitted illumination and the light source for reflected illumination are provided with an ultraviolet absorption filter and an infrared absorption filter to prevent photocuring of the correction liquid staying at the discharge port of the microdispenser, and the correction port without causing clogging of the discharge port A method for correcting a defect in a color filter, characterized in that the correction is performed by applying a correction liquid onto the color filter.   The means for measuring the irradiation time of the irradiation light from the light source for transmitted illumination is provided, and the light source for transmitted illumination is turned off when the irradiation time reaches a preset time. Color filter defect correction method.

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