KR20110064168A - Ips mode transflective liqud crystal display device and manufacturing method thereof - Google Patents

Abstract

PURPOSE: An IPS mode semitransparent type LCD and manufacturing method thereof are provided to have the same transparent area and a reflective area by using an optical hardening. CONSTITUTION: A semitransparent liquid display device includes as follows. A transparent area includes a first liquid cell which is initially arranged to a first direction on a horizontal surface. A reflective area(REF) has a second liquid crystal cell which is initially arranged having an inclination angle about a horizontal surface and a second direction on the horizontal surface. The transparent area and the reflective area has the same cell gap.

Description

IPS mode transflective liquid crystal display and manufacturing method thereof {IPS MODE TRANSFLECTIVE LIQUD CRYSTAL DISPLAY DEVICE AND MANUFACTURING METHOD THEREOF}

The present invention relates to a transflective liquid crystal display device which is driven by an IPS method and a manufacturing method thereof. In particular, the present invention relates to a transflective liquid crystal display device in which the cell gaps of the transmissive part and the reflecting part are driven in the same IPS method, and a manufacturing method thereof.

An active matrix liquid crystal display device displays an image using a thin film transistor (TFT) as a switching element. The liquid crystal display device can be miniaturized compared to a cathode ray tube (CRT), which is applied to a display device in a portable information device, an office device, a computer, and a television, and is rapidly replacing a cathode ray tube.

Since the liquid crystal display is not a self-light emitting device, a separate light source is required. The liquid crystal display may be represented by a transmissive type or a reflective type depending on a light source. In the transmissive liquid crystal display, a backlight unit is installed to face a lower substrate of two upper and lower substrates into which liquid crystal is injected to transmit light incident from the backlight unit toward the projection surface. On the other hand, the reflective liquid crystal display device forms a reflective surface on the lower substrate of the two upper and lower substrates into which the liquid crystal is injected, thereby preventing external light incident to the lower substrate via the upper substrate or a separate auxiliary light. It is reflected toward the display surface.

Recently, research on semi-transmissive liquid crystal display devices, which can have advantages of transmissive and reflective, has been activated.

1 is a schematic view showing a transflective liquid crystal display device according to the prior art. The transflective liquid crystal display is divided into a reflection region REFC and a transmission region TRNC. The lower substrate SUBLC of the reflective region RECC includes the reflective common electrode REFCOMC and the pixel electrode PXLC formed between the insulating layers GIC and PASSIC. The lower alignment layer ALGLC is formed on the entire surface. The lower substrate SUBLC of the transmission area TRNC includes a transparent common electrode TRNCOMC and a pixel electrode PXLC formed between the insulating layers GIC and PASSIC. In addition, a color filter CFC and an upper alignment layer ALGUC are formed on the upper substrate SUBUC of the reflective region REFC. The upper substrate SUBUC and the lower substrate SUBLC are bonded together with the liquid crystal layer LCC interposed therebetween, thereby completing a transflective liquid crystal display panel.

An upper polarizing plate POLUC is attached to an upper surface of the transflective liquid crystal display panel, and a lower polarizing plate POLLC is attached to a lower surface thereof. The lower polarizing plate POLLC has a light transmission axis in a first direction, and the upper polarizing plate POLUC has a light transmission axis in a second direction orthogonal to the first direction. In this structure, the light path for displaying an image in the reflection region REFC and the transmission region TRNC is as follows. In FIG. 1, an arrow indicates a path of light in the reflection area RECC and the transmission area TRNC in the transflective liquid crystal display.

In this state, the light passing through the transmission region TRNC passes through the liquid crystal layer LCC only once, while the light passing through the reflection region RECC passes through the liquid crystal layer LCC twice. Due to this characteristic, the cell gap of the liquid crystal layer LCC is changed to equalize the optical retardation value in the reflection region REFC and the transmission region TRNC. To this end, an insulating layer INS is further formed on the color filter CFC of the reflective region REFC. Since the liquid crystal molecules are the same in optical retardation (ie, d 지연 n), the value of n is the same. On the other hand, the d value in the transmissive region TRNC is D2 which is the same cell gap as the optical path, and the d value in the reflective region REFC is twice as large as the cell gap D1. Therefore, in order to make the value d equal to the reflection region RECC and the transmission region TRNC, the cell gap D1 of the reflection region REFC is equal to 1 / th of the cell gap D2 of the transmission region TRNC. Let it be 2.

As described above, the transflective liquid crystal display device according to the prior art has a problem in that cell gaps are not formed over the entire liquid crystal display device. If the cell gap is not constant, an unexpected problem may occur, resulting in poor reliability of the liquid crystal display. In addition, a process for adjusting the cell gap difference is necessary, which leads to an increase in the complexity and cost of the manufacturing process.

SUMMARY OF THE INVENTION An object of the present invention is to provide a semi-transmissive liquid crystal display device in which the liquid crystal cell gap is the same in both the transmission region and the reflection region. Another object of the present invention is to provide a method of manufacturing a transflective liquid crystal display device in which the liquid crystal cell gap is the same in both the transmission region and the reflection region by a simple method using the photocuring method.

In order to achieve the above object, the transflective liquid crystal display according to the present invention comprises: a transmissive region including a first liquid crystal cell initially oriented in a first direction on a horizontal plane; And a reflective region having a second liquid crystal cell initially oriented in a second direction on the horizontal plane and with respect to the horizontal plane.

The cell gap of the transmission area and the reflection area is the same.

The transmission region further includes a pixel electrode and a transparent common electrode arranged in a horizontal direction to apply a horizontal electric field to the first liquid crystal cell.

The reflective region includes a pixel electrode and a reflective common electrode arranged in a horizontal direction to apply a horizontal electric field to the second liquid crystal cell; And an auxiliary electrode arranged perpendicularly to the reflective common electrode to apply a vertical electric field to the second liquid crystal cell.

A liquid crystal material in the first liquid crystal cell and the second liquid crystal cell; And photocurable monomers.

The first direction is a 45 degree direction; The second direction is a 90 degree direction; The inclination angle is characterized in that 50 to 55 degrees.

A first substrate having a thin film transistor, a pixel electrode connected to the thin film transistor, and a common electrode arranged to form a horizontal electric field with the pixel electrode; And a second substrate on which a color filter is formed, wherein the first and second liquid crystal cells are interposed between the first substrate and the second substrate.

An upper polarizing plate having a first polarization direction; The second substrate further includes a lower polarizer having a second polarization direction perpendicular to the first polarization direction.

Any one of the first polarization direction and the second polarization direction may be parallel to or perpendicular to the first direction.

In addition, the method of manufacturing a transflective liquid crystal display according to the present invention includes the steps of defining a transmission region and a reflection region on the first substrate and the second substrate; Forming a TFT substrate including a transparent common electrode and a pixel electrode in the transmission region of the first substrate, and a reflective common electrode and a pixel electrode in the reflection region of the first substrate; Forming a color filter substrate including a color filter on the entirety of the second substrate and a first auxiliary electrode in the reflective region of the second substrate; Bonding the TFT substrate and the color filter substrate to each other with a liquid crystal cell composed of a liquid crystal and a photocuring monomer mixture therebetween to form a liquid crystal panel; Applying an electric field between the reflective common electrode and the first auxiliary electrode to cause the photocuring monomer interposed therebetween to have an inclination angle with respect to a horizontal plane; Irradiating ultraviolet rays to the liquid crystal panel to cure the photocurable monomer having the inclination angle.

The applying of the electric field between the reflective common electrode and the first auxiliary electrode may include applying the electric field such that the inclination angle is 50 degrees to 55 degrees.

The forming of the TFT substrate further comprises: forming a lower alignment film having a first alignment direction in the transmission region and a second alignment direction in the reflection region; The forming of the color filter substrate may further include forming an upper alignment layer having the first alignment direction in the transmission area and having the second alignment direction in the reflection area.

In the transflective liquid crystal display according to the present invention, the liquid crystal cell gap is the same in both the transmission region and the reflection region. Accordingly, the problem of deterioration of reliability caused by the difference in the liquid crystal cell gap does not occur. In addition, the method of manufacturing the transflective liquid crystal display device according to the present invention prevents the optical phase difference between the transmission region and the reflection region by the photocuring method using the photocurable monomer. Therefore, no separate optical means for retardation compensation is needed. Therefore, the manufacturing method is simple and the manufacturing cost can be reduced.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 2 to 8. 2 is a plan view showing a transflective liquid crystal display device according to the present invention. 3 is a cross-sectional view illustrating a structure of a transflective liquid crystal display according to a first exemplary embodiment of the present invention, which is taken along the line II ′ of FIG. 2.

A transflective liquid crystal display according to Embodiment 1 of the present invention will be described in detail with reference to FIGS. 2 and 3. The transflective liquid crystal display is divided into a reflection area REF and a transmission area TRN. The data line DL that runs in the vertical direction and the gate line GL that runs in the horizontal direction cross each other to define a pixel area of a substantially rectangular shape. The common electrode is formed in the pixel area. In particular, the reflective common electrode REFCOM made of an opaque metal is formed in the reflective region REF and the transparent common electrode TRNCOM is formed of a transparent conductor such as ITO in the reflective region REF.

The gate electrode G, the reflective common electrode REFCOM formed in the reflective region REF, and the transparent common electrode TRNCOM formed in the transmissive region TRN are included on the lower substrate SUBL. A gate insulating layer GI covering the gate electrode G and the common electrodes REFCOM and TRNCOM is coated on the entire surface. The semiconductor layer ACT, a source electrode S on one side of the semiconductor layer ACT, and a drain electrode D are disposed on the other side of the gate insulating layer GI at a portion overlapping with the gate electrode G. The thin film transistor TFT is protected by a passivation layer PASSI. The pixel electrode PXL in contact with the drain electrode D through the contact hole is formed on the passivation layer PASSI to form a horizontal electric field with the common electrodes REFCOM and TRNCOM. The lower alignment layer ALGL is coated on the entire surface of the lower substrate SUBL on which the pixel electrode PXL is formed. In the lower alignment layer ALGL, the reflective region REF and the transparent region TRN are formed to have directions that are 45 degrees apart from each other. For example, the reflective region REF has an alignment direction in the 45 degree direction, and the transmission region TRN has an alignment direction in the 90 degree direction.

The black matrix BM is disposed at a position corresponding to the gate line GL, the data line DL, and the thin film transistor TFT in the upper substrate SUBU. The color filter CF is disposed in a pixel area occupying between the black matrices BM. The color filter CF may be formed to have an RGB arrangement in accordance with the arrangement of the pixels. The auxiliary electrode AUX is disposed in the reflective region REF on the color filter CF. The auxiliary electrode AUX forms a wire to be used when a voltage is separately applied from the outside. The upper alignment layer ALGL is coated on the entire surface of the upper substrate SUBU including the auxiliary electrode AUX and the color filter CF. In the upper alignment layer ALGU, the reflective region REF and the transparent region TRN are formed to have directions that are 45 degrees apart from each other. For example, the reflective region REF has an alignment direction in the 45 degree direction, and the transmission region TRN has an alignment direction in the 90 degree direction.

The upper substrate SUBU and the lower substrate SUBL are bonded to each other while maintaining a constant gap with the liquid crystal layer LC therebetween. The lower polarizer POLL is attached to the lower substrate SUBL, and the upper polarizer POLU is attached to the upper substrate SUBU. The lower polarizing plate POLL has a light transmission axis in a first direction that is parallel or perpendicular to 90 degrees, which is an alignment direction of the alignment layer of the transmission region TRN. The upper polarizing plate POLU has a light transmission axis in a second direction orthogonal to the lower polarizing plate POLL. For example, the light transmission axis of the lower polarizing plate POLL is 90 degrees, and the light transmission axis of the upper polarizing plate POLU may be set to 0 degrees.

Looking at the optical operation state in the transflective liquid crystal display having such a structure is as follows.

In the transmissive region TRN, visible light generated by a backlight unit (not shown) installed inside the liquid crystal display device passes through the liquid crystal layer LC and moves toward the display surface. When the visible light generated by the backlight unit passes through the lower polarizer POLL, the visible light is polarized in the first direction. The liquid crystal layer LC of the transmission region TRN is aligned in a direction in which the initial alignment state is parallel to or perpendicular to the light transmission axis of the lower polarizer POLL. In this state, light polarized in the first direction does not generate optical anisotropy while passing through the liquid crystal layer LC. 4A illustrates a case where polarized light passes through liquid crystal molecules (LCM) arranged in parallel with the polarization direction. 4B illustrates a case where polarized light passes through liquid crystal molecules LMC arranged in a state perpendicular to the polarization direction. In the case of FIG. 4A, only the transmittance ne in the longitudinal direction is present. In addition, in the case of FIG. 4B, only the transmittance no in one direction exists. Therefore, light polarized in the state shown in FIGS. 4A and 4B does not generate transmittance anisotropy due to liquid crystal molecules (LCM). Therefore, the light passing through the liquid crystal molecules LCM reaches the upper polarizing plate POLU while maintaining the polarization state in the first direction. Since the upper polarizing plate POLU has a light transmission axis in a second direction perpendicular to the first direction, light polarized in the first direction passing through the liquid crystal layer LC may not pass. That is, the black color is expressed in the normal state.

When an electric field is formed between the pixel electrode PXL and the transparent common electrode TRNCOM, the arrangement state of the liquid crystal layer LC is changed. For example, it may be changed in a 45 degree direction in a direction parallel or perpendicular to the light transmission axis of the lower polarizer POLL. In this case, the light polarized in the first direction through the lower polarizer POLL is optically anisotropic in the liquid crystal molecules LCM. 4C illustrates a case where the polarized light passes through the liquid crystal molecules (LCM) inclined at 45 degrees with respect to the polarization direction. That is, the polarized light is affected by both the transmittance ne in the long direction and the transmittance no in the unidirectional direction. Moreover, the longitudinal transmission ne and the unidirectional transmission no have different values. Therefore, the polarized state of the polarized light passing through the liquid crystal molecules (LCM) is changed. The light polarized in the first direction passing through the liquid crystal molecule (LCM) inclined at 45 degrees changes the polarization state in the second direction to reach the upper polarizing plate (POLU). Since the upper polarizing plate POLU has a light transmission axis in the second direction, light whose polarization state is changed in the second direction while passing through the liquid crystal layer LC is passed to display an image. That is, it expresses a white tint in an operating state.

In the reflection area REF, an image is displayed using external light. The external light incident on the reflective region REF is reflected by the reflective common electrode REFCOM via the liquid crystal layer LC and is emitted to the outside via the liquid crystal layer LC. However, the reflection filter REF must operate under the same conditions as the transmission region TRN. The external light passing through the upper polarizer POLU is polarized in the second direction. In order to implement normally black, when the light polarized in the second direction passes through the liquid crystal layer LC and is reflected from the reflective common electrode REFCOM, the light is emitted to the upper polarizer POLU again. It must not pass through the upper polarizer (POLU). In the normal state, when the liquid crystal molecules are parallel or orthogonal to the light transmission axis of the upper polarizing plate POLU, the light polarized in the second direction does not have optical anisotropy in the reflection region REF. That is, when the light polarized in the second direction is reflected by the reflective common electrode REFCOM and reaches the upper polarizing plate POLU, the light is transmitted through the upper polarizing plate POLU while maintaining the polarization state in the second direction. Then, you cannot implement normally black. Therefore, in the reflective region REF, the initial direction of the liquid crystal molecules LCM should be different from that of the transmission region TRN. Therefore, as described above, the initial alignment state of the liquid crystal layer LC in the reflection region REF should be 45 degrees different from the initial alignment state of the liquid crystal layer LC in the transmission region TRN.

In the transflective liquid crystal display according to the first embodiment, the cell gaps of the reflection region REF and the transmission region TRN are the same. This causes a difference in the optical path. That is, the optical path in the reflection area REF is 2d, which is twice the cell gap d, and the optical path in the transmission area TRN has the same value d as the cell gap d. Thus, a problem arises because the results of optical retardation (ie, d ㅿ n) are different. That is, the phase delay value in the reflection region REF is twice the phase delay value in the transmission region TRN. In order to reduce the phase delay value in the reflection region REF, characteristics of the liquid crystal material LCM constituting the liquid crystal cell LC are used. That is, the liquid crystal molecules (LCM) is a material that is denser than air having light transmittance. When light passes through dense media, it slows down. In other words, the phase delay value becomes slow. By using this characteristic, the liquid crystal molecules LCM lying in the horizontal state in the reflective region REF are erected so that the light passes through the dense portion in the reflective region REF longer. 5A and 5B are diagrams illustrating differences in liquid crystal molecule passage paths according to liquid crystal states when light passes through liquid crystal molecules. In FIG. 5A, when the liquid crystal molecules LCM lie in the horizontal direction in the planar direction of the liquid crystal panel, light incident on the liquid crystal panel passes through the liquid crystal molecules by the short axis length a of the liquid crystal molecules LCM. In FIG. 5B, when the liquid crystal molecules LCM are erected by an angle with respect to the horizontal direction in the plane direction of the liquid crystal panel, the light path length when the light entering the liquid crystal panel passes through the liquid crystal molecules LCM is shown. That is, in the state where the liquid crystal molecules LMC are standing, the optical path X is represented by the following equation (1).

That is, since cos θ has a value less than 1, X is always greater than a. In other words, the light passing through the reflective region REF is more out of phase than the light passing through the transmission region TRN. At this time, the value of θ is experimentally adjusted so that the light passing through the reflection area REF does not occur in the reflection area REF and the transmission area TRN with respect to the cell gap of the designed liquid crystal display device. Give phase difference. In Example 1, it was most preferable that the value of θ be between 50 and 55 degrees.

In conclusion, the transflective liquid crystal display according to the first exemplary embodiment of the present invention includes a reflective region REF and a transmissive region TRN, and a cell gap of the reflective region REF and the transmissive region TRN is the same. The liquid crystal cell in the reflection area REF is oriented in the 45 degree direction on the horizontal plane and in the direction inclined by 50 to 55 degree with respect to the horizontal plane, and the liquid crystal cell in the transmissive area TRN is in the 90 degree direction on the horizontal plane and in the horizontal plane. It is characterized by being oriented in the phase.

Hereinafter, a method of manufacturing a transflective liquid crystal display device according to Embodiment 1 of the present invention will be described with reference to FIGS. 6A to 6E. 6A through 6E are cross-sectional views illustrating a method of manufacturing a transflective liquid crystal display device according to a first embodiment of the present invention, which is taken along the line II ′ of FIG. 2.

First, the TFT substrate 100 of the transflective liquid crystal display device is completed. On the first transparent substrate SUBL, the gate line GL, the gate electrode G branching from the gate line GL, the reflective common electrode REFCOM made of an opaque metal in the reflective region REF, and the transmissive region TRN ), A transparent common electrode TRNCOM is formed of a transparent conductor such as ITO. The gate insulating film GI is apply | coated whole on it. The semiconductor layer ACT is formed at a position overlapping with the gate electrode G on the gate insulating layer GI. The source electrode S is formed on one side of the semiconductor layer ACT and the drain electrode D is formed on the other side. The source electrode S is branched from the data line DL running in the vertical direction perpendicular to the gate line GL. The passivation layer PASSI is coated on the entire surface of the substrate SUBL on which the thin film transistor TFT is formed. After exposing a part of the drain electrode D, the pixel electrode PXL is formed on the passivation layer using a transparent electrode such as ITO. When the pixel electrode PXL is formed as shown in FIG. 2, a horizontal electric field is formed between the pixel electrode PXL and the common electrodes TRNCOM and REFCOM in the direction of the substrate plane. The lower alignment layer ALGL is formed on the TFT substrate on which the pixel electrode PXL is completed. (FIG. 6A)

Next, the color filter substrate 200 of the transflective liquid crystal display device is completed. The black matrix BM is formed at a position corresponding to the gate line GL, the data line DL, and the thin film transistor TFT on the second transparent substrate SUBU. The color filter CF is formed in the pixel area occupying between the black matrices BM. The color filters CF may be arranged in an RGB form. On the substrate SUBU on which the black matrix BM and the color filter CF are formed, the auxiliary electrode AUX is formed of a transparent conductive material such as ITO only in the reflection region TRN. An alignment layer ALGU is formed on the entire surface of the substrate SUBU. In this case, it is preferable that the alignment layer ALGU is made of an organic material to planarize the level difference between the reflection region REF and the transmission region TRN, which may occur due to the auxiliary electrode AUX. (FIG. 6B)

The TFT substrate 100 and the color filter substrate 200 are bonded to each other via the liquid crystal layer LC. The bottom plate alignment layer ALGL located on the top layer of the TFT substrate 100 is subjected to alignment treatment. At this time, the reflective region REF is aligned so that the initial orientation of the liquid crystal is 45 degrees, and the transmissive region TRN is aligned so that the initial alignment of the liquid crystal is 90 degrees. The TFT substrate and the color filter substrate on which the alignment process is completed are bonded together with the liquid crystal material (LCM) through a liquid crystal layer (LC) to which a photocurable monomer ((Reactive Mesogen) RM) is added. ) And the cell gap of the transmissive region TRN are maintained at the same interval, so that the cell gap has the same 'd' value throughout the substrate (FIG. 6C).

In the state where the TFT substrate 100 and the color filter substrate 200 are bonded together, a voltage is applied between the reflective common electrode REFCOM and the auxiliary electrode AUX to fill the cell gap of the reflective region REF. LCM) and photocuring monomer (RM) is applied a vertical electric field. At this time, the vertical voltage value is adjusted so that the liquid crystal material (LCM) and the photocurable monomer (RM) are erected about 50 to 55 degrees in the horizontal direction. On the other hand, the liquid crystal material LCM and the photocuring monomer RM filled in the cell gap of the transmissive region TRN where the vertical voltage is not taken over maintain the initial alignment state by the upper alignment layer ALGU and the lower alignment layer ALGL. Has one state. In this state, ultraviolet rays are radiated to the entire liquid crystal display panel to cure the photocurable monomer RM. Then, the liquid crystal material LCM of the reflective region REF is erected by the upper alignment layer ALGU and the lower alignment layer ALGL in a state where the liquid crystal material LCM is erected about 50 to 55 degrees in the horizontal direction by the photocuring monomer RM. It is oriented in the 45 degree direction which is a state. On the other hand, the liquid crystal material LCM filled in the cell gap of the transmissive region TRN is in the horizontal state by the photocuring monomer RM, and is 90 degrees which is the initial alignment state by the upper alignment layer ALGU and the lower alignment layer ALGL. Direction is oriented. When the liquid crystal cell is initially oriented by the alignment layers ALGU and ALGL, the liquid crystal cell does not actually have a horizontal state of 0 degrees. In practice, the vertical inclination angles of the alignment films ALGU and ALGL have an inclination angle inclined with respect to the horizontal plane of less than about 2 degrees. However, this degree of inclination is regarded as the same as the horizontal state. (FIG. 6D)

The transflective liquid crystal display panel is completed. An upper polarizing plate POLU is attached to an outer surface of the color filter substrate, and a lower polarizing plate POLL is attached to an outer surface of the TFT substrate. 6E, a further necessary process is performed to complete the transflective liquid crystal display.

In Example 1 described above, an example in which the auxiliary electrode AUX is formed only in the reflective region REF and the initial alignment of the liquid crystal cell LC in the reflective region REF in the vertical direction is described. However, an initial alignment of the liquid crystal cell LC in the transmission region TRN in an inclined state vertically may remove the phase difference generated when the cell gaps of the transmission region TRN and the reflection region REF are the same. . In this case, the auxiliary electrode AUX may be formed only in the transmission region TRN. FIG. 7 is a cross-sectional view of a transflective liquid crystal display according to a second exemplary embodiment of the present invention in which an auxiliary electrode AUX is formed in a transmissive region TRN.

In another embodiment, the liquid crystal cell LC of the reflective region REF or the transmissive region TRN may be selectively inclined in the vertical direction. In this case, the first auxiliary electrode AUX1 may be formed in the reflective region REF and the second auxiliary electrode AUX2 may be formed in the transmission region AUX. The first auxiliary electrode AUX1 and the second auxiliary electrode AUX2 may be electrically separated from each other to input different voltages. This has the advantage that the cell gap can be kept more constant than when the auxiliary electrode AUX is provided only in one region. FIG. 8 is a cross-sectional view of a transflective liquid crystal display device according to a third exemplary embodiment of the present invention in which a reflection region includes a first auxiliary electrode and a transmission region includes a second auxiliary electrode.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

1 is a schematic view showing a transflective liquid crystal display device according to the prior art.

2 is a plan view showing a transflective liquid crystal display device according to the present invention;

3 is a cross-sectional view showing the structure of a transflective liquid crystal display according to a first embodiment of the present invention, which is taken along the line II ′ of FIG. 2.

4A is a diagram illustrating a case where polarized light passes through liquid crystal molecules arranged parallel to the polarization direction.

4B is a diagram illustrating a case where polarized light passes through liquid crystal molecules arranged in a state perpendicular to the polarization direction.

4C is a diagram illustrating a case where polarized light passes through liquid crystal molecules inclined at 45 degrees with respect to the polarization direction.

5A and 5B are diagrams illustrating differences in liquid crystal molecules passing paths according to liquid crystal states when light passes through liquid crystal molecules.

6A through 6E are cross-sectional views illustrating a method of manufacturing a transflective liquid crystal display according to a first embodiment of the present invention, which is taken along the line II ′ of FIG. 2.

FIG. 7 is a cross-sectional view of a transflective liquid crystal display according to a second embodiment of the present invention in which an auxiliary electrode AUX is formed in a transmission region TRN.

FIG. 8 is a cross-sectional view of a transflective liquid crystal display according to a third embodiment of the present invention in which a reflection region includes a first auxiliary electrode and a transmission region includes a second auxiliary electrode. FIG.

Description of the Related Art

SUBLC, SUBL: Lower board SUBUC, SUBU: Upper board

REFCOMC, REFCOM: Reflective Common Electrode TRNCOMC, TRNCOM: Transmissive Common Electrode

GIC, PASSIC, INS: Insulation PASSI: Protective Film

GI: gate insulating film PXLC, PXL: pixel electrode

ALGLC, ALGL: lower alignment layer ALGUC, ALGU: upper alignment layer

POLUC, POLU: Upper polarizer POLLC, POLL: Lower polarizer

LCC, LC: liquid crystal layer BMC, BM: black matrix

CFC, CF: color filter TFT: thin film transistor

G: gate electrode S: source electrode

D: drain electrode DL: data line

GL: Gate Line ACT: Semiconductor Layer

REFC, REF: reflection area TRNC, TRN: transmission area

LCM: liquid crystal molecule (liquid crystal material)

RM: Reactive Mesogen AUX: Auxiliary Electrode

AUX1: first auxiliary electrode AUX2: second auxiliary electrode

Claims (18)

A transmission area including a first liquid crystal cell initially oriented in a first direction on a horizontal plane; And a reflective region having a second liquid crystal cell initially oriented in a second direction on the horizontal plane and having an inclination angle with respect to the horizontal plane. The method of claim 1, And a cell gap of the transmissive area and the reflective area is the same. The method of claim 1, And a pixel electrode and a transparent common electrode arranged in the horizontal direction to apply a horizontal electric field to the first liquid crystal cell in the transmissive region. The method of claim 1, The reflective region includes a pixel electrode and a reflective common electrode arranged in a horizontal direction to apply a horizontal electric field to the second liquid crystal cell; And A semi-transmissive liquid crystal display device further comprising an auxiliary electrode arranged perpendicularly to the reflective common electrode to apply a vertical electric field to the second liquid crystal cell. The method of claim 1, In the first liquid crystal cell and the second liquid crystal cell, Liquid crystal material; And A semi-transmissive liquid crystal display device comprising a photocurable monomer. The method of claim 1, The first direction is a 45 degree direction; The second direction is a 90 degree direction; The inclination angle is a transflective liquid crystal display device, characterized in that 50 to 55 degrees. The method of claim 1, A first substrate having a thin film transistor, a pixel electrode connected to the thin film transistor, and a common electrode arranged to form a horizontal electric field with the pixel electrode; Further comprising a second substrate having a color filter, And the first and second liquid crystal cells are interposed between the first substrate and the second substrate. The method of claim 7, wherein An upper polarizing plate having a first polarization direction; The second substrate further comprises a lower polarizing plate having a second polarization direction perpendicular to the first polarization direction. The method of claim 8, A transflective liquid crystal display device, wherein any one of the first polarization direction and the second polarization direction is parallel or perpendicular to the first direction. Defining a transmission region and a reflection region on the first substrate and the second substrate; Forming a TFT substrate including a transparent common electrode and a pixel electrode in the transmission region of the first substrate, and a reflective common electrode and a pixel electrode in the reflection region of the first substrate; Forming a color filter substrate including a color filter on the entirety of the second substrate and a first auxiliary electrode in the reflective region of the second substrate; Bonding the TFT substrate and the color filter substrate to each other with a liquid crystal cell composed of a liquid crystal and a photocuring monomer mixture therebetween to form a liquid crystal panel; Applying an electric field between the reflective common electrode and the first auxiliary electrode to cause the photocuring monomer interposed therebetween to have an inclination angle with respect to a horizontal plane; And irradiating ultraviolet rays to the liquid crystal panel to cure the photocurable monomer having the inclination angle. 11. The method of claim 10, In the step of forming the liquid crystal panel, a semi-transmissive liquid crystal display device manufacturing method characterized in that the cell gap of the liquid crystal panel is uniformly bonded over the entire surface. 11. The method of claim 10, The applying of the electric field between the reflective common electrode and the first auxiliary electrode may include applying the electric field such that the inclination angle is 50 degrees to 55 degrees. 11. The method of claim 10, The forming of the TFT substrate further comprises: forming a lower alignment film having a first alignment direction in the transmission region and a second alignment direction in the reflection region; The forming of the color filter substrate may further include forming an upper alignment layer having the first alignment direction in the transmission area and having the second alignment direction in the reflection area. 13. The method of claim 12, And the first alignment direction and the second alignment direction have a 45 degree difference. 13. The method of claim 12, And attaching a lower polarizing plate to the outside of the TFT substrate and an upper polarizing plate to the outside of the color filter. The method of claim 15, The lower polarizing plate has a first light transmission axis parallel or perpendicular to the first alignment direction; The upper polarizing plate has a second light transmission axis perpendicular to the first light transmission axis, characterized in that the semi-transmissive liquid crystal display device manufacturing method. 11. The method of claim 10, Forming the color filter substrate, And forming a second auxiliary electrode electrically separated from the first auxiliary electrode in the transmission region of the second substrate. The method of claim 17, And instead of applying the electric field between the reflective common electrode and the first auxiliary electrode, applying the electric field between the transparent common electrode and the second auxiliary electrode.

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