KR100958036B1 - Mask device for exposure of alignment film for multi domain photo alignment - Google Patents

Abstract

PURPOSE: A mask device for exposure of an alignment film for multi domain photo alignment is provided to form a multi domain which can keep various alignment directions by one mask, thereby preventing manufacture of an additional mask and simplifying a complex manufacture process. CONSTITUTION: The first substrate comprises a gate line(220), a data line(230), a common bus line(240), a switching element arranged between the gate line and the data line and an exposure area(EA). The exposure area is defined by the gate line and the data line to form a horizontal electric field by the pixel electrode and the common electrode. The exposure area is defined by unit areas in which a horizontal electric field of each different angle is formed to form a multi domain. The angle is different per each unit area based on voltage strength applied to the pixel electrode and the common electrode.

Description

Mask device for exposure of alignment film for multi-domain photo-alignment {MASK DEVICE FOR EXPOSURE OF ALIGNMENT FILM FOR MULTI DOMAIN PHOTO ALIGNMENT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mask device for exposing a photo-alignment film, and more particularly, the mask forms a pixel electrode and a common electrode on the same substrate and uses a transverse electric field generated between the two electrodes to form a single mask. By forming a multi domain that can maintain various alignment directions, it is possible to prevent additional masks and simplify complicated manufacturing processes when using an alignment layer for optical alignment in manufacturing a liquid crystal display. A mask device for exposing an alignment film for multi-domain photo-alignment.

In general, liquid crystal displays (LCDs) are used for terminals or video devices of various information devices in place of cathode ray tubes (CRTs) because they have characteristics such as light weight, thinness, and low power consumption. .

The liquid crystal display (LCD) has a problem in that the viewing angle is narrow due to a large difference in retardation of light depending on the viewing angle used as an anisotropic liquid crystal.

In order to solve this problem, Korean Laid-Open Patent Publication No. 1998-57609 (Method of manufacturing a liquid crystal display device having a wide viewing angle) is a method for forming a multi domain, and a method using patterning of a polarizing plate. Although presenting, there is a lot of difficulty in forming a multi-domain according to the polarization axis formed through the stretching in the polarizing plate manufacturing process.

LCDs can be classified into two types: a transmissive liquid crystal display device using a backlight as a light source and a reflective liquid crystal display device using natural light as a light source. In order to solve the shortcomings, a transflective liquid crystal display device has been proposed. Since the transflective liquid crystal display device can use both a reflection type and a transmission type as needed, it has a relatively low power consumption and can be used even in a dark environment.

In the conventional transflective liquid crystal display, a phase difference of light emitted from the transmissive part and the reflecting part is generated so that a retardation film is applied to the reflecting part to eliminate the phase difference of the transmissive part and the reflecting part. In this case, a process of adding a phase difference film and patterning is added to increase a panel manufacturing process time, and a defect occurs due to the addition of a film coating process and an increase in the number of processes occurring in the patterning process. The possibilities also increase.

In order not to apply such a retardation film, a multi-orientation technique may be applied to vary the alignment directions of the liquid crystals of the transmissive portion and the reflecting portion. Since the mask is exposed two or more times, there is a problem of causing an increase in processing time and an increase in manufacturing cost by additionally manufacturing the mask.

Meanwhile, Korean Patent Application No. 2005-90484 (Liquid Crystal Photomask and Liquid Crystal Photomask Apparatus, Pattern Forming Method, and Flat Panel Display Manufacturing Method) describes the manufacture of a photo mask using a liquid crystal display (LCD). However, this conventional technology is only intended to transmit or opaque light using a liquid crystal display device, which makes it difficult to form various polarization regions.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to form a pixel electrode and a common electrode on the same substrate, and to form a mask using a transverse electric field generated between the two electrodes. By forming a multi domain that can maintain various alignment directions, it is possible to prevent additional masks and simplify complicated manufacturing processes when using an alignment layer for optical alignment in manufacturing a liquid crystal display. The present invention provides a mask device for exposing an alignment film for multi-domain photo-alignment.

In order to achieve the above object, an aspect of the present invention is a mask device for alignment film exposure for optical alignment comprising a first substrate, a second substrate, and a liquid crystal layer interposed between the first substrate and the second substrate. The first substrate may include a gate line and a data line intersecting each other on a substrate, a common bus line spaced in parallel with the gate line, a switching element disposed at an intersection of the gate line and the data line, and the switching element. A pixel electrode electrically connected to receive a signal of the data line, a common electrode electrically connected to the common bus line, and receiving a common signal, and defined as a first region and a second region by the gate line and the data line. And a first exposure area, wherein the first zero area is planarly affected by an electric field formed between the pixel electrode and the common electrode during mask driving. It is to provide a mask device for the alignment film exposure for multi-domain photo-alignment, characterized in that the multi-domain is formed in the exposure area is maintained by the rotation direction of the liquid crystal located in the and the second region at different arbitrary angles. .

Preferably, a light source for photoalignment may be further provided on the mask device.

Preferably, the polarizing plate is further provided between the light source and the multi mask device.

Preferably, a light shielding film may be formed on the second substrate to shield light from the remaining areas except for the exposure area.

Preferably, the pixel electrode and the common electrode may be formed to generate electric fields in different directions in planar directions when driving a mask in the first region and the second region.

Preferably, the pixel electrode and the common electrode may be formed only in one of the first region and the second region.

Preferably, the pixel electrode and the common electrode may be formed at the same height as the cell gap between the first substrate and the second substrate.

The barrier rib may be further formed below the pixel electrode and the common electrode at the same height as the cell gap between the first substrate and the second substrate.

Preferably, the arbitrary angle may be adjusted according to the shape of the pixel electrode and the common electrode and the intensity of the applied voltage.

Preferably, the alignment of the liquid crystal is a horizontal alignment in which the first substrate and the second substrate are oriented in a direction such that they are 180 degrees apart.

As described above, an alignment film exposure mask device for multi-domain optical alignment according to the present invention can be manufactured through a basic manufacturing process of a liquid crystal display (LCD), and the mask forms a pixel electrode and a common electrode on the same substrate. By using a transverse electric field generated between the two electrodes to form a multi-domain that can maintain a variety of alignment directions with a mask (Mask) and to form an alignment film for the optical alignment in the manufacturing of the liquid crystal display device When used, there is an advantage that can effectively prevent the production of additional masks.

In addition, according to the present invention, it is possible to provide ease of mask fabrication, simplify a complicated manufacturing process, and reduce manufacturing cost of a liquid crystal display device through a single mask and a reduction of defect occurrence rate through process simplification. There is an advantage in that it is possible to make a liquid crystal display device with a secure screen quality.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

1 is a plan view schematically illustrating a lower substrate of an alignment layer exposure mask apparatus for multi-domain photo-alignment according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1, and FIG. It is sectional drawing along the line B-B 'of FIG. 1, and FIG. 4 is sectional drawing along the C-C' line of FIG.

1 to 4, an alignment film exposure mask device for multi-domain optical alignment according to an exemplary embodiment of the present invention is similar to a liquid crystal display (LCD). 6) and the second substrate 100 (see FIG. 6) are separated from each other, and the liquid crystal layer 300 (FIG. 6) oriented in one direction between the first substrate 200 and the second substrate 100. Intervening).

Here, the alignment of the liquid crystal is a horizontal alignment in which the first substrate 200 and the second substrate 100 are aligned in a direction different from each other by 180 degrees.

The second substrate 100 may be formed by patterning a light shielding film (for example, a black matrix (BM)) for shielding other areas except for an exposure area (EA), which will be described later. Can be.

The first substrate 200 is arranged such that a gate line 220 and a data line 230 cross each other on the substrate 210, and the gate line 220 and the data line 230 intersect each other. ), A thin film transistor (TFT), which is a switching element, is disposed.

The thin film transistor TFT is switched by a signal of the gate line 220 to transfer a signal of the data line 230 to the pixel electrode 250 which will be described later.

The common bus line 240 is spaced apart from the gate line 220 at regular intervals and formed in parallel with the gate line 220. The common bus line 240 is electrically connected to the common electrode 260 to be described later. Connected to the common signal continuously applied to the common electrode 260.

In addition, an exposure area EA is defined by the gate line 220 and the data line 230, and the exposure area EA may be divided into a first area and a second area.

In addition, the pixel electrode 250 is formed in the first region and the second region of the exposure area EA by being electrically connected to the thin film transistor TFT.

That is, the pixel electrode 250 has a plate-shaped first pixel electrode 250a including slits in the first area of the exposure area EA, and one side edge of the first pixel electrode 250a in the second area. The portion extends toward the common bus line 240 and includes a rod-shaped second pixel electrode 250b formed parallel to the data line 230.

The second pixel electrode 250b has a predetermined height (for example, the same height as the cell gap of the liquid crystal display device) under the second pixel electrode 250b to form a smooth electric field with the common electrode 260 which will be described later. It is preferable that the barrier rib is formed by forming a barrier rib (BR) and depositing a metal film (eg, ITO) having a predetermined thickness thereon.

An insulating layer IL may be further formed between the substrate 210 and the pixel electrode 250. The pixel electrode 250 may be formed of a transparent metal material to facilitate light transmission. It is preferable to form using.

The common electrode 260 is electrically connected to the common bus line 240.

That is, the common electrode 260 is a plate-shaped second common electrode 260b formed with an insulating film under the pixel electrode in the first area of the exposure area EA, and a common bus line in the second area. The rod-shaped first common electrode 260a and the first common electrode 260a extending along the longitudinal direction of the common bus line 240 to be electrically connected to the upper portion of the one side 240 through the contact hole CH. One end of the third common electrode 260c extends toward the gate line 220 and connects the first common electrode 260a and the second common electrode 260b.

The first and third common electrodes 260a and 260c have the same characteristics as the second pixel electrode 250b in order to form a smooth electric field with the pixel electrode 250. A barrier rib (BR) having a predetermined height (for example, the same height as the cell gap of the liquid crystal display device) is formed under the 260c, and a metal film (for example, ITO, etc.) is deposited on the barrier rib.

In addition, when a light source for photoalignment is provided on the mask device, a polarizer 270 (see FIG. 6) may be further provided between the light source and the mask device.

In addition, an insulating layer IL of a predetermined thickness is formed between the common bus line 240, the first common electrode 260a, the substrate 210, and the second and third common electrodes 260b and 260c. Can be further formed.

Meanwhile, in one embodiment of the present invention, although one exposure area EA is implemented in one mask, the present invention is not limited thereto, and a plurality of gate lines 220, data lines 230, and The common bus lines 240 may be arranged to implement an exposure area EA in an array form.

Hereinafter, the operation principle of the alignment film exposure mask device for multi-domain photo-alignment according to an embodiment of the present invention will be described in detail.

FIG. 5 is a conceptual view illustrating a liquid crystal array direction in the initial state of a liquid crystal and a mask driving plane according to an embodiment of the present invention, and FIG. 6 is a view illustrating an initial state of the liquid crystal and a mask driving state according to an embodiment of the present invention. It is a conceptual diagram which shows the liquid crystal orientation and the polarization direction in cross section.

1 to 6, first, light incident from an exposure apparatus (not shown) passes through a polarizing plate 270 attached to the first substrate 200, and is formed with a single axis of polarized light. As the polarization passes through the liquid crystal layer 300, rotation of the polarization axis occurs along the alignment direction of the liquid crystal.

In this case, the liquid crystal positioned in the first region of the exposure area EA is at a predetermined angle (preferably about 0 degrees) due to the influence of the electric field formed between the first pixel electrode 250a and the second common electrode 260b. The liquid crystal array is rotated by), and the light passing through this region is transmitted while the optical axis of incident light is rotated at a predetermined angle along the rotation direction of the liquid crystal.

Similarly, the liquid crystal positioned in the second area of the exposure area EA is formed between one side of the first pixel electrode 250a and between the second pixel electrode 250b and the first and third common electrodes 260a and 260c. Under the influence of the electric field, the liquid crystal array is rotated at a certain angle (preferably, about 45 degrees), and the light passing through this area has a constant angle (about 45 degrees) of the incident light along the rotational direction of the liquid crystal. Permeability).

In this case, the rotation angle of the liquid crystal of the first region and the second region may be controlled by adjusting the restoring force of the liquid crystal or the intensity of the voltage applied to the pixel electrode 250 and the common electrode 260.

Although a preferred embodiment of the mask device for oriented film exposure for multi-domain photo-alignment according to the present invention has been described above, the present invention is not limited thereto, but the scope of the claims and the detailed description of the invention and the accompanying drawings are various. It is possible to carry out the transformation by the branch and this also belongs to this invention.

1 is a plan view schematically illustrating a lower substrate of a mask device for exposing an alignment film for multi-domain photoalignment according to an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG. 1.

3 is a cross-sectional view taken along line BB ′ of FIG. 1.

4 is a cross-sectional view taken along the line CC ′ of FIG. 1.

FIG. 5 is a conceptual view illustrating a liquid crystal array direction in the initial state of the liquid crystal and in driving the mask according to an embodiment of the present invention.

FIG. 6 is a conceptual diagram illustrating the liquid crystal alignment and the polarization direction in the initial state of the liquid crystal and the mask driving according to the exemplary embodiment of the present invention.

Claims (10)

delete delete delete delete In the mask device for the alignment film exposure for optical alignment comprising a first substrate, a second substrate, and a liquid crystal layer interposed between the first substrate and the second substrate, The first substrate, A gate line, a data line and a common bus line intersected on the substrate, a switching element disposed at an intersection of the gate line and the data line, and defined by the gate line and the data line and transversely by the pixel electrode and the common electrode. Including an exposure area where an electric field is formed, The exposure area is defined as a plurality of unit areas in which transverse electric fields of different predetermined angles are formed in plan view, and multi domains are formed. Masking device for the alignment film exposure for multi-domain photo-alignment, characterized in that it is adjusted differently every time. 6. The method of claim 5, When the unit region is two as the first region and the second region, The first region includes a plate-shaped first common electrode and a plate-shaped first pixel electrode including a slit on the first common electrode. The second region is electrically connected to the common bus line through a contact hole, and includes a rod-shaped second common electrode formed along a length direction of the common bus line, one end of the second common electrode, and the first common electrode. A third common electrode having a bar shape formed to be connected to each other, and a second pixel electrode connected to the first pixel electrode to form a bar shape so as to face the third common electrode. Mask apparatus for oriented film exposure. 6. The method of claim 5, And a light shielding film for shielding the remaining areas other than the exposure area on the second substrate. 6. The method of claim 5, A light source for optical alignment is additionally provided, and a polarizing plate is further provided between the light source and the mask device so that a single axis of polarized light is incident on the liquid crystal layer. Device. 6. The method of claim 5, The unit area, A pixel electrode and a common electrode provided to form different transverse electric fields at different angles in each unit region, wherein the pixel electrode and the common electrode in each unit region are electrically connected to each other, and the pixel electrode is the switching element. And the common electrode is electrically connected to the common bus line. The method of claim 9, And a barrier rib having a predetermined height is formed under the pixel electrode and the common electrode of at least some of the pixel electrodes and the common electrodes in the unit region.

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