KR101365771B1 - optical member and method of fabricating the same, liquid crystal display device having the optical member and method of fabricating the same - Google Patents

Abstract

The present invention relates to an optical member and a method of manufacturing the same, a liquid crystal display device having the optical member, and a method of manufacturing the same.

A liquid crystal display according to the present invention includes: signal lines including gate wirings and data wirings intersecting on a first substrate to define a pixel region having a transmissive region and a reflective region; A thin film transistor connected to the gate line and the data line; A reflection plate formed in the reflection area; A first electrode formed in the pixel region and connected to the thin film transistor; A second electrode alternately disposed with the first electrode; A second substrate facing the first substrate; A liquid crystal layer interposed between the first substrate and the second substrate, having a λ / 4 phase delay corresponding to the reflective region and having a λ / 2 phase delay corresponding to the transmission region; And a phase retardation member having a phase retardation portion corresponding to the reflection area on the second substrate.

As a result, the present invention has a second effect that is robust against process variations because the color contrast ratio does not decrease even when a variation occurs in the cell gaps of the reflective and transmissive regions due to the process variation.

Phase delay member

Description

Optical member and manufacturing method thereof, liquid crystal display device having optical member, and manufacturing method therefor {optical member and method of fabricating the same, liquid crystal display device having the optical member and method of fabricating the same}

1 is a cross-sectional view showing one pixel of a conventional reflective transmissive liquid crystal display device.

2 is a graph showing black luminance according to cell gap variation in a conventional transflective liquid crystal display device;

3 is a cross-sectional view illustrating one pixel of a transflective liquid crystal display according to an exemplary embodiment of the present invention.

4A is a cross-sectional view (off state) showing a state change of light along a path of light in a reflection area of a reflective liquid crystal display according to the present invention.

4B is a cross-sectional view (off state) showing a state change of light along a path of light in a transmissive region of the reflective liquid crystal display according to the present invention.

5A is a cross-sectional view (on state) showing a state change of light along a path of light in a reflection area of a reflective liquid crystal display according to the present invention.

5B is a cross-sectional view illustrating a state change of light along a path of light in a transmissive region of the reflective transmissive liquid crystal display according to the present invention (on state).

6A to 6D are cross-sectional views showing a method of manufacturing a phase delay member as a first embodiment according to the present invention.

7A to 7D are cross-sectional views showing a method of manufacturing a phase delay member as a second embodiment according to the present invention.

8A to 8F are cross-sectional views showing a method of manufacturing a phase delay member as a third embodiment according to the present invention.

9 is a plan view showing a phase delay member according to the present invention.

Description of the Related Art [0002]

200: reflection-transmissive liquid crystal display panel 210: first substrate

211: insulation pattern 213: reflective electrode

215: common electrode 217: pixel electrode

219: liquid crystal layer 220: second substrate

230: first phase delay member 230a: phase delay unit

230b: non-phase delay unit 241: first polarizing plate

242: second polarizing plate

The present invention relates to an optical member and a method of manufacturing the same, a liquid crystal display device having the optical member, and a method of manufacturing the same.

As the information society develops, the demand for display devices is increasing in various forms. In response, liquid crystal display devices (LCDs), plasma display panels (PDPs), and electroluminescent displays have been recently developed. Various flat panel display devices such as Electro Luminescent Display Device (VFD) and Vacuum Fluorescent Display Device (VFD) have been studied, and some of them are already used as display devices in various devices.

Among them, liquid crystal displays are being widely used as a substitute for the CRT (Cathode Ray Tube) for mobile image display devices due to the advantages of excellent image quality, light weight, thinness, and low power consumption. Various monitors are developed.

A general liquid crystal display device may be broadly divided into a liquid crystal panel displaying an image and a driving unit for applying a driving signal to the liquid crystal panel, wherein the liquid crystal panel includes first and second substrates bonded to each other with a predetermined space, and It consists of the liquid crystal layer injected between the 1st, 2nd board | substrate.

Hereinafter, a conventional liquid crystal display and a method of manufacturing the same will be described with reference to the accompanying drawings.

1 is a cross-sectional view illustrating one pixel of a conventional reflective transmissive liquid crystal display device.

FIG. 1 is a diagram illustrating an arrangement relationship of components in order to clearly show a difference between a reflecting portion and a transmitting portion of a conventional reflective transmissive liquid crystal display.

Conventional reflection-transmissive liquid crystal display devices have various driving methods, but are shown as transverse electric field liquid crystal display devices.

In the conventional reflective liquid crystal display panel, the first substrate 110 and the second substrate 120 are disposed to face each other, and the liquid crystal layer 119 is interposed between the first substrate 110 and the second substrate 120. It is.

The first phase delay member 131 and the first polarization member 141 are disposed below the first substrate 110.

The second phase delay member 132 and the second polarization member 142 are disposed on the second substrate 120.

Although not shown, a backlight unit is provided on the rear surface of the first substrate 110 as a light source, and the light provided from the backlight unit passes through the first polarizing member 141 and enters the liquid crystal display panel.

The liquid crystal display panel 100 defines a reflective area RA and a transparent area TA. A reflective electrode 113 is formed on the first substrate 110 to correspond to the reflective area RA. The reflective electrode 113 serves to improve the light efficiency by reflecting the external light source to the front.

In the reflective liquid crystal display, since the optical paths in the reflective area RA and the transparent area TA are different, the cell gap d1 of the transparent area TA is the cell gap d1 of the reflective area RA. Is about twice that of

In order to have such a dual cell gap structure, a thick insulating pattern 111 is further formed only in the reflective region RA.

The common electrode 115 and the pixel electrode 117 are alternately disposed in the reflection area RA and the transmission area TA, and are disposed in the transverse electric field between the common electrode 115 and the pixel electrode 117. The liquid crystal layer 119 is driven by this.

The conventional reflective transmissive liquid crystal display device having the above configuration includes a first phase retardation member 131 and a second phase retardation member 132, and may further include an optical film.

In the conventional transflective liquid crystal display device, in particular, the transverse electric field type liquid crystal display device, the screen should be in a dark state when no voltage is applied to the common electrode 115 and the pixel electrode 117.

However, in the conventional reflection-transmissive liquid crystal display device, the relation between the optical axes of the first and second phase delay members 131 and 132 and the optical axes of the liquid crystal layer 119 is defined by the reflection area RA and the transmission area TA. Sensitive to cell gap variation. Thus, when cell gap fluctuation occurs during the manufacturing process, black luminance increases rapidly and the liquid crystal layer 119 is not driven so that the screen is dark even though the screen is dark.

2 is a graph showing black luminance according to a cell gap variation in a conventional transflective liquid crystal display.

As shown in FIG. 2, the conventional transflective liquid crystal display device has a cell gap d2 of a reflective area RA and a cell gap d1 of a transmissive area TA originally designed according to various process conditions during a liquid crystal display panel manufacturing process. When the variation occurs, the larger the cell gap variation is, the higher the black luminance value is.

In a transverse electric field type liquid crystal display, when a voltage is not applied to the common electrode 115 and the pixel electrode 117, the screen becomes dark, and a voltage is applied to the common electrode 115 and the pixel electrode 117. When the screen is bright when not applied, the color contrast ratio is excellent and the picture quality is clear.

However, the conventional reflection-transmissive liquid crystal display device having the above-described configuration is vulnerable to cell gap variation, and when the cell gap variation becomes large, there is a problem in that image quality deteriorates and the image quality deteriorates.

A first object of the present invention is to provide an optical member having a phase retardation unit selectively and a method of manufacturing the same.

The present invention provides a reflective liquid crystal display device having excellent image quality even when a cell gap is changed due to process variation by arranging an optical member having a phase retardation unit selectively corresponding to the reflecting portion outside the liquid crystal display panel in the reflective liquid crystal display device, and the manufacture thereof. It is a second object to provide a method.

In order to achieve the first object described above, the optical member includes a substrate; And at least one phase delay unit disposed on the substrate at regular intervals.

In addition, the manufacturing method of the optical member according to the present invention in order to achieve the above first object, comprising the steps of: preparing a substrate; And forming at least one phase delay unit disposed at regular intervals on the substrate.

According to an aspect of the present invention, there is provided a liquid crystal display device including: signal lines including gate wirings and data wirings defining a pixel region having a transmissive region and a reflective region crossing on a first substrate; A thin film transistor connected to the gate line and the data line; A reflection plate formed in the reflection area; A first electrode formed in the pixel region and connected to the thin film transistor; A second electrode alternately disposed with the first electrode; A second substrate facing the first substrate; A liquid crystal layer interposed between the first substrate and the second substrate, having a λ / 4 phase delay corresponding to the reflective region and having a λ / 2 phase delay corresponding to the transmission region; And a phase retardation member having a phase retardation portion corresponding to the reflection area on the second substrate.

In addition, in order to achieve the above-described second object, a method of manufacturing a liquid crystal display device according to the present invention includes a gate wiring and a data wiring defining a pixel region having a transmissive region and a reflective region intersecting on a first substrate; Forming an array element including a wiring and a thin film transistor connected to the data wiring; Forming a reflecting plate in the reflecting region; Forming a first electrode connected to the thin film transistor and a second electrode alternately disposed with the first electrode in the pixel region; Joining a second substrate facing the first substrate, having a λ / 4 phase delay corresponding to the reflective region between the first substrate and the second substrate and having a λ / 2 phase delay corresponding to the transmissive region Forming a liquid crystal layer having a; Providing a phase delay member having a phase delay portion corresponding to the reflection area; And disposing the phase delay member on an outer surface of the second substrate.

According to the exemplary embodiments of the present invention, the image quality is improved by applying an optical member having a phase delay value to the outside of the reflective liquid crystal display panel.

In addition, the present invention according to the embodiments described above is robust to process variation because the color contrast ratio does not decrease even when the cell gap between the reflective region and the transmissive region occurs due to the process variation in manufacturing the reflective transmissive liquid crystal display device.

In the present invention, when the reflective liquid crystal display device is manufactured by the transverse electric field method, since the alignment direction of the alignment layer of the reflective region and the transparent region is the same, the process is simple and no manufacturing process is required, thereby improving manufacturing yield.

Hereinafter, an optical member and a reflective liquid crystal display having the same according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view showing one pixel of a reflective liquid crystal display according to an exemplary embodiment of the present invention.

Although the reflection type liquid crystal display device according to the present invention has various driving methods, it will be described as a transverse electric field type liquid crystal display device.

Although not specifically illustrated, the liquid crystal display according to the present invention has signal lines including gate wirings and data wirings intersecting on a first substrate to define a pixel region having a transmissive region and a reflective region.

A thin film transistor connected to the gate line and the data line is formed on the first substrate.

In addition, a reflective electrode having good reflection characteristics is formed in the reflective region to use an external light source.

In the pixel area, a first electrode connected to the thin film transistor and a second electrode alternately disposed with the first electrode are formed.

When the voltage is applied to the first electrode and the second electrode, a transverse electric field is formed between the first electrode and the second electrode.

Further, a liquid crystal layer having a λ / 4 phase delay corresponding to the reflective region and having a λ / 2 phase delay corresponding to the transmissive region is interposed between the second substrates facing the first substrate.

As illustrated in FIG. 3, in the reflective liquid crystal display panel 200, a first substrate 210 and a second substrate 220 are disposed to face each other, and the first substrate 210 and the second substrate 220 are disposed. The liquid crystal layer 219 is interposed therebetween.

The reflection type liquid crystal display panel 200 defines a reflection area RA and a transmission area TA.

The first polarizing member 241 is disposed below the first substrate 210.

The phase delay member 230 and the second polarization member 242 having the phase delay unit 230a are selectively disposed on the second substrate 220.

The phase delay unit 230a of the phase delay member 230 is formed to correspond to the reflection area RA.

The non-phase retardation unit 230b of the phase retardation member 230 is formed to correspond to an area other than the reflective area RA (including the transmission area TA).

The phase delay member 230 has a predetermined phase delay value in the phase delay unit 230a, and the non-phase delay unit 230b has a phase delay value of zero.

The material of the phase retardation unit 230a of the phase retardation member 230 may be made of a material that causes phase retardation of light, for example, a polymer material including polycarbonate.

The material of the phase delay unit 230a of the phase delay member 230 may be made of a material that causes phase retardation of light, for example, a liquid crystal material including reactive liquid crystal molecules.

The material of the non-phase delay unit 230b of the phase delay member 230 may be formed of, for example, a liquid crystal material having an isotropic phase.

 The material of the non-phase delay unit 230b of the phase delay member 230 may be made of, for example, a transparent insulating material.

In addition, the non-phase delay unit 230b of the phase delay member 230 may be an empty space.

Although not shown, a backlight unit is provided as a light source on a rear surface of the first substrate 210, and the light provided from the backlight unit passes through the first polarizing member 241 to transmit the reflective liquid crystal display panel 200. Enter into.

An insulating pattern 211 for a dual cell gap structure is formed on the first substrate 210 corresponding to the reflective area RA, and the insulating pattern 211 has an optical path and the light path in the reflective area RA. This is for matching the optical path in the transmission area TA.

The cell gap d1 of the transmission area TA is about twice the cell gap d1 of the reflection area RA.

The reflective electrode 213 is formed on the insulating pattern 211 to correspond to the reflective region RA.

The reflective electrode 213 reflects an external light source to the front to improve light efficiency.

An uneven pattern may be further formed between the insulating pattern 211 and the reflective electrode 213.

An upper surface of the insulating pattern 211 may have an uneven structure.

The insulating pattern 211 may be formed on the second substrate 220 corresponding to the reflective area RA.

The common electrode 215 and the pixel electrode 217 are alternately disposed in the reflection area RA and the transmission area TA, and a transverse electric field is formed between the common electrode 215 and the pixel electrode 217. As a result, the liquid crystal molecules of the liquid crystal layer 219 are rotated and driven horizontally.

In general, the average angle rotated by the transverse electric field of the liquid crystal molecules is 45 degrees.

In particular, in the transflective liquid crystal display device according to the present invention, the transverse electric field type liquid crystal display device has a normally black mode in which a screen becomes dark when no voltage is applied to the common electrode 215 and the pixel electrode 217. Black mode).

4A is a cross-sectional view illustrating a state change of light along a path of light in a reflection area of a transflective liquid crystal display according to the present invention, and FIG. 4B is a state of light along a path of light in a transmissive area of a reflective liquid crystal display according to the present invention. It is a cross section showing the change.

4A and 4B are views illustrating a state change of light when no transverse electric field is generated in the liquid crystal layer 219 because no voltage is applied to the common electrode 215 and the pixel electrode 217. State '.

4A is a cross-sectional view taken along the optical path in the reflective region, and thus, both the path when the light is incident and the path when the light is reflected from the reflective electrode 213 and are emitted.

It is preferable that the first transmission axis of the first polarizing plate 241 and the second transmission axis of the second polarizing plate 242 are perpendicular to each other.

When the angle is 0 ° based on the second transmission axis of the second polarizing plate 242, the first transmission axis of the first polarizing plate 241 is 90 °.

The phase delay value of the phase delay unit 230a of the phase delay member 230 may be λ / 2, and the optical axis may have, for example, 15 °.

The optical axis of the liquid crystal molecules between the first substrate 210 and the second substrate 220 is aligned to form 75 ° with the second transmission axis of the second polarizing plate 242.

The cell gap d2 of the reflection area RA is about 1/2 of the cell gap d1 of the transmission area TA, and the phase delay value is 'λ / 4' in the off state. That is, when passing through the liquid crystal layer 219 of the reflective region RA, the linearly polarized light is changed into circularly polarized light, and the circularly polarized light is changed into linearly polarized light.

In the transmission area TA, the phase delay value is 'λ / 2' in the off state. That is, when passing through the liquid crystal layer 219 of the transmission area TA, the linearly polarized light is changed into linearly polarized light whose polarization direction is symmetrical.

Hereinafter, the process of changing the polarization state along the path of light in the reflection area RA will be described.

First, light provided from an external light source enters the second polarizing plate 242.

The second polarizing plate 242 passes only the light having the same optical axis as the second transmission axis with respect to the incident light.

Therefore, the light passing through the second polarizing plate 242 becomes the first light ① linearly polarized on the second transmission axis.

Hereinafter, for convenience of explanation and understanding, the second transmission axis of the second polarizing plate 242 is referred to as 0 ° and the state change of light will be described based on this.

The first light ① passing through the second transmission axis of the second polarizing plate 242 passes through the phase delay unit 230a of the phase delay member 230 and is delayed in phase so that the second light ② is passed. Becomes

Here, the phase retardation value of the phase retardation unit 230a of the phase retardation member 230 is λ / 2, and the optical axis is tilted by 15 ° with respect to the second transmission axis.

Accordingly, the second light ② passing through the phase delay unit 230a of the phase delay member 230 is delayed by λ / 2 so that the second light ② is optically aligned with the first light ①. This is a linearly polarized light having a 30 ° tilted optical axis.

Thereafter, the second light ② passes through the liquid crystal layer 219 having a phase retardation value of λ / 4 and changes to a third light ③.

Since the phase retardation value of the liquid crystal layer 219 is λ / 4, the third light ③ becomes right circularly polarized light.

The third light ③ is reflected by the reflective electrode 213 and enters the liquid crystal layer 219 as a fourth light ④ that is circularly polarized in the same manner as the third light ③.

Here, the right polarized light is reflected from the reflective electrode 213 to the right polarized light because it is in the same polarization state when the light travels along the path of the light, and when the light reflected from the front is seen. The right circularly polarized light should be viewed as left circularly polarized light.

The reflected fourth light ④ passes through the liquid crystal layer 219 having a phase retardation value of λ / 4 and is changed into a fifth light ⑤.

The fifth light ⑤ is linearly polarized light because the phase retardation value of the liquid crystal layer 219 is λ / 4.

In this case, the fifth light ⑤ is the light passing through the liquid crystal layer 219 having the phase delay value λ / 4 twice.

That is, the fifth light ⑤ is a linearly polarized light in which the optical axis is tilted by 120 ° because it is rotated by 90 ° with respect to the optical axis of the second light ②.

Thereafter, the fifth light ⑤ passes through the phase delay unit 230a of the phase delay member 230 to become the sixth light ⑥.

Here, the phase retardation unit 230a of the phase retardation member 230 has a phase retardation value of λ / 2, and the optical axis is tilted by 15 °. Therefore, the phase retardation unit 230a of the phase retardation member 230 is changed. The sixth light ⑥ passed through is rotated by 30 ° to become linearly polarized light perpendicular to the second transmission axis of the second polarizing plate 242.

Therefore, the sixth light ⑥ does not pass through the second polarizing plate 242, so that the light transmittance is 'black level'.

Accordingly, light incident on the second polarizing plate 242 of the reflective region RA passes through the phase delay member 230 and the liquid crystal layer 219 of the reflective region RA and is reflected by the reflective electrode 213. After passing through the liquid crystal layer 219 and the phase delay member 230 of the reflective region RA, the second polarizer 242 is blocked.

Hereinafter, as illustrated in FIG. 4B, a process of changing the polarization state along the path of light in the transmission area TA will be described.

First, light provided from the backlight light source is incident on the first polarizer 241.

The first polarizing plate 241 passes only the light having the same optical axis as the first transmission axis with respect to the incident light.

Therefore, the light passing through the first polarizing plate 241 becomes the first light ① linearly polarized with the first transmission axis.

Since the second transmission axis of the second polarizing plate 242 is referred to as 0 ° and the state change of light is described based on this, the first light ① becomes linearly polarized light having a 90 ° optical axis.

The first light ① passing through the first transmission axis of the first polarizing plate 241 passes through the liquid crystal layer 219 having a phase retardation value of λ / 2 and is converted into a second light ②.

Since the phase retardation value of the liquid crystal layer 219 is λ / 2, the second light ② becomes linearly polarized light having the opposite polarization direction.

The second light ② passes through the non-phase delay unit 230b of the phase delay member 230 as it is.

Accordingly, since the second light ② passing through the liquid crystal layer 219 becomes linearly polarized light perpendicular to the second transmission axis of the second polarizing plate 242, the second light ② is the second light. All of the polarization plate 242 is blocked so that the light transmittance is 'black level' (Black level).

Therefore, light incident on the first polarizing plate 241 of the transmission area TA passes through the liquid crystal layer 219 of the transmission area TA and is blocked by the second polarizing plate 242.

Since the reflective liquid crystal display according to the present invention is driven in a normally black mode, when a proper voltage is applied to the common electrode 215 and the pixel electrode 217, the screen is bright, that is, a white display is displayed. Done.

5A is a cross-sectional view illustrating a state change of light along a path of light in a reflection area of a transflective liquid crystal display according to the present invention, and FIG. 5B is a state of light along a path of light in a transmissive area of a reflective liquid crystal display according to the present invention. It is a cross section showing the change.

5A and 5B are views illustrating a state change of light when a transverse electric field is generated in the liquid crystal layer 219 by applying a white voltage to the common electrode 215 and the pixel electrode 217. It is called.

5A is a cross-sectional view taken along the optical path in the reflection area RA, and thus, both the path when the light is incident and the path when the light is reflected from the reflective electrode 213 and are emitted.

It is preferable that the first transmission axis of the first polarizing plate 241 and the second transmission axis of the second polarizing plate 242 are perpendicular to each other.

When the angle is 0 ° based on the second transmission axis of the second polarizing plate 242, the first transmission axis of the first polarizing plate 241 is 90 °.

In addition, the phase delay value of the phase delay unit 230a of the phase delay member 230 may be 'λ / 2', and the optical axis may have, for example, 15 °.

The optical axis of the liquid crystal molecules between the first substrate 210 and the second substrate 220 is aligned to form 75 ° with the second transmission axis of the second polarizing plate 242.

The cell gap d2 of the reflection area RA is about 1/2 of the cell gap d1 of the transmission area TA, and the phase delay value is 'λ / 4' in the off state. That is, when passing through the liquid crystal layer 219 of the reflective region RA, linearly polarized light is changed into circularly polarized light, and circularly polarized light is changed into linearly polarized light.

In the transmission area TA, the phase delay value is 'λ / 2' in the off state. That is, when passing through the liquid crystal layer 219 of the transmission area TA, the linearly polarized light is changed into linearly polarized light whose polarization direction is symmetrical.

Hereinafter, a process of changing the polarization state along the path of light in the reflection area RA will be described with reference to FIG. 5A.

First, light provided from an external light source enters the second polarizing plate 242.

The second polarizing plate 242 passes only the light having the same optical axis as the second transmission axis with respect to the incident light.

Accordingly, the light passing through the second polarizing plate 242 becomes the first light ① linearly polarized with the second transmission axis.

Hereinafter, for convenience of explanation and understanding, the second transmission axis of the second polarizing plate 242 is referred to as 0 ° and the state change of light will be described based on this.

The first light ① passing through the second transmission axis of the second polarizing plate 242 passes through the phase delay unit 230a of the phase delay member 230 and is delayed in phase so that the second light ② is do.

Here, the phase retardation value of the phase retardation unit 230a of the phase retardation member 230 is λ / 2, and the optical axis is tilted 15 ° with respect to the second transmission axis.

Accordingly, the second light ② passing through the phase delay unit 230a of the phase delay member 230 is delayed by λ / 2 so that the second light ② is optically aligned with the first light ①. This is a linearly polarized light having a 30 ° tilted optical axis.

Thereafter, the second light ② passes through the liquid crystal layer 219 having a phase delay value of 0 and changes to a third light ③.

When an electric field is generated, the liquid crystal molecules of the liquid crystal layer 219 rotate up to 45 ° horizontally, so that the average alignment axis of the liquid crystal molecules of the liquid crystal layer 219 is equal to the first polarization axis 241 of the first polarizing plate 241. The second polarization plate 242 is tilted at 45 ° with respect to the second polarization axis.

Therefore, since the light passing through the liquid crystal layer 219 has no phase delay, the third light ③ becomes linearly polarized light in the same manner as the second light ②.

Accordingly, the third light ③ becomes linearly polarized light having an optical axis in which the optical axis is inclined by 30 °.

 Thereafter, the third light ③ is reflected by the reflective electrode 213 and is incident on the liquid crystal layer 219 as the fourth light ④ linearly polarized with the third light ③.

Here, the linearly polarized light is reflected by the linearly polarized light from the reflective electrode 213 because it is in the same polarization state when it follows the path of light in the traveling direction of the light, and when the light reflected from the front is seen The third light (4) and the fourth light (4) should be considered that the polarization direction is symmetrically changed.

Accordingly, the fourth light ④ becomes linearly polarized light having an optical axis in which the optical axis is inclined by 30 °.

The reflected fourth light ④ passes through the liquid crystal layer 219 having a phase delay value of 0 as it is and is converted into a linearly polarized fifth light ⑤.

Thus, the fifth light ⑤ becomes linearly polarized light having an optical axis in which the optical axis is inclined by 30 ° with the first light ①.

Thereafter, the fifth light ⑤ passes through the phase delay unit 230a of the phase delay member 230 to become the sixth light ⑥.

Here, the phase retardation unit 230a of the phase retardation member 230 has a phase retardation value of λ / 2, and the optical axis is tilted by 15 °. Therefore, the phase retardation unit 230a of the phase retardation member 230 is changed. The sixth light ⑥ passed through is rotated 30 ° to become linearly polarized light parallel to the second transmission axis of the second polarizing plate 242.

That is, the sixth light ⑥ is linearly polarized light having a polarization direction parallel to the first light ①.

Therefore, since the sixth light ⑥ passes through the second polarizing plate 242 as it is, light transmittance becomes “white level”.

Accordingly, light incident on the second polarizing plate 242 of the reflective region RA passes through the phase delay member 230 and the liquid crystal layer 219 of the reflective region RA and is reflected by the reflective electrode 213. After passing through the liquid crystal layer 219 and the phase delay member 230 of the reflective region RA, all of the light is transmitted from the second polarizing plate 242.

Hereinafter, as illustrated in FIG. 5B, a process of changing the polarization state along the path of light in the transmission area TA will be described.

First, light provided from the backlight light source is incident on the first polarizer 241.

The first polarizing plate 241 passes only the light having the same optical axis as the first transmission axis with respect to the incident light.

Therefore, the light passing through the first polarizing plate 241 becomes the first light ① linearly polarized with the first transmission axis.

Since the second transmission axis of the second polarizing plate 242 is referred to as 0 ° and the state change of light is described based on this, the first light ① becomes linearly polarized light having a 90 ° optical axis.

The first light ① passing through the first transmission axis of the first polarizing plate 241 passes through the liquid crystal layer 219 having a phase delay value of 0 and changes to a second light ②.

Since the phase retardation value of the liquid crystal layer 219 is 0, the second light ② becomes linearly polarized light parallel to the second transmission axis of the second polarizing plate 242. Through all of the second polarizing plate 242, the light transmittance is 'white level'.

According to the present invention, the phase delay member 230 includes a phase delay unit 230a and a non-phase delay unit 230b, and the phase delay unit 230a corresponds to the reflection region RA, and the non-phase The delay unit 230b corresponds to the remaining area of the liquid crystal display except for the reflective area RA.

The phase delay member 230 may be in the form of a film, may be in the form of a plate, or may be formed on one surface of the first substrate 210 or the second substrate 220.

The phase delay unit 230a of the phase delay member 230 serves as a half wave plate (HWP) because the phase delay value is λ / 2, and the optical axis is designed to have 15 ° with the transmission axis of the adjacent polarizing plate. It may be, but is not limited thereto.

The optical axis of the phase delay unit 230a, the first transmission axis of the first polarizing plate 241, the second transmission axis of the second polarizing plate 242, and the alignment axis of the liquid crystal layer 219 are mutually optically disposed. There may be many things to consider.

According to an exemplary embodiment of the present invention, a phase delay member 230 having a phase delay value is selectively applied to an exterior of the reflective transmissive liquid crystal display panel 200 so that variations in the cell gap between the reflective area RA and the transmission area TA may be caused by process variations. Even if it occurs, the black luminance does not increase, so the color contrast ratio is improved.

In addition, the present invention improves the manufacturing yield since the alignment direction of the alignment layer of the reflective region RA and the transmissive region TA is the same when the reflective transmissive liquid crystal display device is manufactured by the transverse electric field method. .

Hereinafter, a method of manufacturing a phase delay member according to the present invention will be described with reference to embodiments.

6A to 6D are cross-sectional views showing a method of manufacturing a phase delay member as a first embodiment according to the present invention.

Here, the material of the phase retardation unit 330a of the phase retardation member 330 may be made of a material that causes phase retardation of light, such as the liquid crystal material 360 including the reactive liquid crystal molecules 361.

As shown in FIG. 6A, an alignment layer 353 is coated on the base substrate 351, and the alignment layer 353 is aligned.

The alignment process of the alignment layer 353 may include a rubbing method and a non-rubbing method such as UV irradiation or ion beam irradiation.

A photoreactive liquid crystal material is coated on the alignment layer 353 to form a photoreactive liquid crystal layer 360.

The photoreactive liquid crystal material may include a UV curable reactive mesogen, a binder monomer, a liquid crystal (LC), a solvent, a photo initiator, and an additive.

The liquid crystal may be a nematic liquid crystal.

In the photoreactive liquid crystal layer 360, the liquid crystal molecules 361 are aligned with the pretilt by the alignment layer 353 on the base substrate 351 to have a predetermined phase delay value.

The phase delay value δ is

δ = Δnd

(δ: phase retardation value of liquid crystal, Δn: difference between normal refractive index and abnormal refractive index of liquid crystal, d: thickness)

Accordingly, the phase delay value may be determined by adjusting the thickness of the liquid crystal material used and the photoreactive liquid crystal layer 360.

Here, the phase retardation value of the photoreactive liquid crystal layer 360 may be λ / 2.

The base substrate 351 may be made of a flexible material or may be made of a hard material.

Preferably, the base substrate 351 is a transparent substrate.

The base substrate 351 may be a first substrate or a second substrate of the reflective liquid crystal display.

As shown in FIG. 6B, the photoreactive liquid crystal layer 360 formed on the alignment layer 353 is covered with a mask 365 and irradiated with light to selectively cure the photoreactive liquid crystal layer 360.

Thereafter, the mask 365 is removed.

As shown in FIG. 6C, the uncured photoreactive liquid crystal material is removed from the base substrate 351 to form a photoreactive liquid crystal layer pattern 360a.

The region where the photoreactive liquid crystal layer 360 remains is a portion corresponding to the reflective region RA of the reflective liquid crystal display, and the region where the photoreactive liquid crystal material has been removed is reflected by the reflective liquid crystal display. Except the region RA, the portion corresponds to the region including the transmission region TA.

As shown in FIG. 6D, the phase retardation member 330 is completed by covering the protective film 352 on the base substrate 351 on which the photoreactive liquid crystal layer pattern 360a is formed.

The phase retardation member 330 may include a phase retardation portion 330a, that is, a portion where the photoreactive liquid crystal layer pattern 360a is formed and a non-phase retardation portion 360b, that is, the photoreactive liquid crystal layer 360. Contains the removed part.

The phase delay unit 330a of the phase delay member 330 is formed to correspond to the reflection area RA.

The non-phase delay unit 330b of the phase delay member 330 is formed to correspond to an area other than the reflection area RA.

The method of forming the photoreactive liquid crystal layer pattern 360a of the phase retardation member 330 may use a photo lithography process.

Specifically, the light is cured by irradiating the entire surface of the photoreactive liquid crystal material without applying a mask on the photoreactive liquid crystal material t formed on the base substrate.

Thereafter, a photoresist pattern may be formed on the cured photoreactive liquid crystal layer, and the photoreactive liquid crystal layer may be etched using the photoresist pattern as a mask to form a photoreactive liquid crystal layer pattern.

7A to 7D are cross-sectional views illustrating a method of manufacturing the phase delay member 430 as a second embodiment according to the present invention.

Here, the material of the phase retardation unit 430a of the phase retardation member 430 may be made of a material that causes phase retardation of light, such as a liquid crystal material including the reactive liquid crystal molecules 461.

As shown in FIG. 7A, an alignment film 453 is coated on the base substrate 451 and the alignment film 453 is oriented.

The alignment treatment of the alignment layer 453 may include a rubbing method and a non-rubbing method such as UV irradiation or ion beam irradiation.

A photoreactive liquid crystal material is coated on the alignment layer 453 to form a photoreactive liquid crystal layer 460.

The photoreactive liquid crystal material may include a UV curable reactive mesogen, a binder monomer, a liquid crystal (LC), a solvent, a photo initiator, and an additive.

The liquid crystal may be a nematic liquid crystal.

As shown in FIG. 7B, a mask 465 is placed on the photoreactive liquid crystal layer 460 formed on the alignment layer 453, and light is irradiated to selectively cure the photoreactive liquid crystal layer 460. .

Thereafter, the mask 465 is removed.

As shown in FIG. 7C, the base substrate 451 on which the cured photoreactive liquid crystal layer 460a and the uncured photoreactive liquid crystal layer 460b are formed is subjected to a predetermined heat treatment process. The liquid crystal molecules 461 of the layer 460b have an isotropic phase.

The cured photoreactive liquid crystal layer 460a has an anisotropic phase.

When the photoreactive liquid crystal layer 460 is heated above Tni (the temperature at which the nematic liquid crystal phase transitions to an isotropic phase), the uncured photoreactive liquid crystal layer 460b phase transitions into an isotropic phase to obtain a phase retardation value. Don't have

In the heat treatment process, the cured photoreactive liquid crystal layer 460a is cured and does not undergo a phase transition even when heated to a temperature above the Tni.

The heat treatment process may be performed at a temperature of 50 ℃ ~ 150 ℃.

After the liquid crystal molecules 461 of the uncured photoreactive liquid crystal layer 460b are phase-transferred to an isotropic phase, the photoreactive liquid crystal layer 460 is irradiated with light (UV) to photoreactive to have the isotropic phase. The liquid crystal layer 460b is also cured.

 Here, the photoreactive liquid crystal layer 460b in which the liquid crystal molecules have an isotropic phase and is cured is a portion corresponding to the remaining regions except for the reflective region RA in the reflective transmissive liquid crystal display, and the liquid crystal molecules 461 are anisotropic phase. The cured photoreactive liquid crystal layer 460a is a portion corresponding to the reflective region RA in the reflective liquid crystal display.

As shown in FIG. 7D, a protective film 452 is formed on the base substrate 451 on which the photoreactive liquid crystal layer 460b pattern having the isotropic phase and the photoreactive liquid crystal layer 460a pattern having the anisotropic phase are formed. The phase delay member 430 is completed.

The phase retardation member 430 as described above includes a phase retardation portion 430a, that is, a portion in which a photoreactive liquid crystal layer 460a pattern in which the liquid crystal molecules 461 have an anisotropic phase is formed and a non-phase retardation portion 430b. That is, the liquid crystal molecules 461 include a portion where the photoreactive liquid crystal layer 460b pattern having an isotropic phase is formed.

The phase delay unit 430a of the phase delay member 430 is formed to correspond to the reflection area RA.

The non-phase retardation unit 430b of the phase retardation member 430 is formed to correspond to the area including the transmission area TA except for the reflection area RA.

8A to 8F are cross-sectional views illustrating a method of manufacturing a phase delay member as a third embodiment according to the present invention.

Here, the material of the phase delay unit 530a of the phase delay member 530 may be made of a material that causes phase retardation of light, such as a liquid crystal material including the reactive liquid crystal molecules 561.

As shown in FIG. 8A, an alignment film 553 is coated on the base substrate 551 and the alignment film 553 is oriented.

The alignment treatment of the alignment layer 553 may include a rubbing method and a non-rubbing method such as UV irradiation or ion beam irradiation.

A photoreactive liquid crystal material is coated on the alignment layer 553 to form a photoreactive liquid crystal layer 560.

The photoreactive liquid crystal material may include a photocurable reactive mesogen, a binder monomer, a liquid crystal (LC), a solvent, a photoinitiator, and an additive.

The liquid crystal may be a nematic liquid crystal.

As shown in FIG. 8B, a mask 565 is applied to the photoreactive liquid crystal layer 560 formed on the alignment layer 553 and irradiated with light (UV) to selectively cure the photoreactive liquid crystal layer 560. .

Thereafter, the mask 565 is removed.

As shown in FIG. 8C, an uncured photoreactive liquid crystal material is removed from the base substrate 551 to form a photoreactive liquid crystal layer pattern 560a.

The region where the photoreactive liquid crystal layer 560 remains is a portion corresponding to the reflective region RA of the reflective liquid crystal display, and the region where the photoreactive liquid crystal material is removed is a reflective region in the reflective liquid crystal display. Except for RA, the portion corresponds to an area including the transmission area TA.

The method of forming the photoreactive liquid crystal layer pattern 560a may use a photolithography process.

Specifically, the photoreactive liquid crystal material formed on the base substrate 551 is cured by irradiating light on the entire surface of the photoreactive liquid crystal material without covering the mask.

Thereafter, a photoresist pattern may be formed on the cured photoreactive liquid crystal layer, and the photoreactive liquid crystal layer may be etched using the photoresist pattern as a mask to form a photoreactive liquid crystal layer pattern.

As illustrated in FIG. 8D, an overcoat layer 567 is formed by covering a transparent insulating material on the base substrate 551 on which the photoreactive liquid crystal layer pattern 560a is formed.

The overcoat layer 567 is formed to be substantially equal to the thickness of the photoreactive liquid crystal layer pattern 560a.

Thereafter, as shown in FIG. 8E, a photoresist pattern 569 is formed on the overcoat layer 567.

The photoresist pattern 569 covers a portion where the photoreactive liquid crystal layer pattern 560a is not formed.

Thereafter, the overcoat layer 567 is etched using the photoresist pattern 569 as an etch mask to form the overcoat layer pattern 567a.

Accordingly, a portion where the photoreactive liquid crystal layer pattern 560a is formed is formed in a portion corresponding to the reflective region RA in the reflective transmissive liquid crystal display, and a portion where the overcoat layer pattern 567a is formed is the reflective liquid crystal display. The portion corresponding to the remaining area of the device except the reflective area RA.

As shown in FIG. 8F, a phase retardation member 530 is completed by covering a protective film 552 on the base substrate 551 on which the photoreactive liquid crystal layer pattern 560a and the overcoat layer pattern 567a are formed. do.

The phase retardation member 530 described above includes a phase retardation portion 530a, that is, a portion where the photoreactive liquid crystal layer pattern 560a is formed, and a non-phase retardation portion 530b, that is, an overcoat layer pattern 567a. Include the part.

The phase delay unit 530a of the phase delay member 530 is formed to correspond to the reflection area RA.

The non-phase delay unit 530b of the phase delay member 530 is formed to correspond to an area other than the reflection area RA.

9 is a plan view showing a phase delay member according to the present invention.

The phase delay member 530 according to the present invention may be attached on the first substrate or the second substrate of the reflective liquid crystal display.

In addition, the substrate may be directly formed on the first substrate or the second substrate, and the base substrate may be the first substrate or the second substrate.

As illustrated in FIG. 9, the phase delay member 530 includes a phase delay unit 530a having a phase delay value corresponding to the reflection area RA, and the remaining area except for the reflection area RA. Corresponding to the non-phase delay unit 530b having no phase delay value.

The phase delay member 530 having the phase delay unit 530a and the non-phase delay unit 530b may be manufactured by the above-described embodiments.

According to the present invention, a phase retardation member having a phase retardation value is selectively applied to an exterior of a transflective liquid crystal display panel, so that black luminance does not increase even when a variation occurs in the cell gap between the reflection region and the transmission region due to process variation, thereby improving color contrast ratio. .

In addition, the present invention improves the production yield since the direction of alignment of the alignment layer of the reflective region and the transparent region is the same when the reflective liquid crystal display device is manufactured by the transverse electric field method.

As described above, the optical member, the manufacturing method thereof, the liquid crystal display device having the optical member, and the manufacturing method thereof according to the present invention are not limited to the above-mentioned embodiments, and the technical features of the present invention It will be apparent to those skilled in the art that modifications and / or modified embodiments are included in the scope of the present invention.

The present invention has a first effect of improving image quality by applying an optical member having a phase retardation value to the outside of the reflective liquid crystal display panel.

According to the present invention, even when a variation occurs in the cell gap between the reflection region and the transmission region due to the process variation, the color contrast ratio is not lowered, thereby having a second effect that is robust to the process variation.

In addition, in the present invention, when the reflective liquid crystal display device is manufactured by the transverse electric field method, since the alignment direction of the alignment layer of the reflection region and the transmission region is the same, a third process is simple and the manufacturing yield is improved without requiring a separate division alignment process. Has the effect of.

Claims (27)

Board; And A phase delay member having at least one phase delay portion disposed on the substrate at regular intervals, The phase retardation member includes a base substrate, an alignment film formed on the base substrate, a liquid crystal layer including photoreactive liquid crystal molecules formed on the alignment film, and a protective film formed on the liquid crystal layer. absence. delete delete The method according to claim 1, And the phase retardation value of the phase retarder is λ / 2. The method according to claim 1, The liquid crystal layer pattern having an isotropic phase is formed around the phase delay unit. The method according to claim 1, The optical member, characterized in that formed in the periphery of the phase delay portion is a transmission pattern for transmitting the phase of light as it is. delete Preparing a substrate; Forming a phase retardation member having at least one phase retardation portion disposed at regular intervals on the substrate, Forming the phase delay member, Forming an alignment layer on the base substrate; Aligning the alignment layer; Forming a liquid crystal layer including photoreactive liquid crystal molecules on the alignment layer; Covering a mask exposing a region corresponding to the phase delay unit on the liquid crystal layer; Irradiating light onto the mask to cure the liquid crystal layer corresponding to the phase delay unit; Removing the liquid crystal layer under the mask to leave the cured liquid crystal layer pattern; And Forming a protective film on the substrate having the liquid crystal layer pattern formed thereon. Preparing a substrate; Forming a phase retardation member having at least one phase retardation portion disposed at regular intervals on the substrate, Forming the phase delay member, Forming an alignment layer on the base substrate; Aligning the alignment layer; Forming a liquid crystal layer including photoreactive liquid crystal molecules on the alignment layer; Covering a mask exposing a region corresponding to the phase delay unit on the liquid crystal layer; Irradiating light onto the mask to cure the liquid crystal layer corresponding to the phase delay unit; Removing the mask and heat treating the liquid crystal layer to phase-transfer the liquid crystal layer below the mask to an isotropic phase; And Photocuring the liquid crystal layer. Preparing a substrate; Forming a phase retardation member having at least one phase retardation portion disposed at regular intervals on the substrate, Forming the phase delay member, Forming an alignment layer on the base substrate; Aligning the alignment layer; Forming a liquid crystal layer including photoreactive liquid crystal molecules on the alignment layer; Covering a mask exposing a region corresponding to the phase delay unit on the liquid crystal layer; Irradiating light onto the mask to cure the liquid crystal layer corresponding to the phase delay unit; Removing the liquid crystal layer under the mask to leave the cured liquid crystal layer pattern; Forming a transmissive layer through which a phase of light passes through the front surface of the substrate on which the liquid crystal layer pattern is formed; Forming a photoresist pattern exposing a region corresponding to the phase delay part on the transmission layer; And etching the transmission layer using the photoresist pattern as an etch mask to form a transmission pattern around the phase delay unit. Signal lines including gate lines and data lines intersecting on the first substrate to define a pixel region having a transmissive region and a reflective region; A thin film transistor connected to the gate line and the data line; A reflection plate formed in the reflection area; A first electrode formed in the pixel region and connected to the thin film transistor; A second electrode alternately disposed with the first electrode; A second substrate facing the first substrate; A liquid crystal layer interposed between the first substrate and the second substrate, having a λ / 4 phase delay corresponding to the reflective region and having a λ / 2 phase delay corresponding to the transmission region; And At least one phase delay unit disposed on the second substrate at regular intervals, And the phase delay unit includes an alignment film formed on the substrate, a liquid crystal layer including photoreactive liquid crystal molecules formed on the alignment film, and a protective film formed on the liquid crystal layer. 12. The method of claim 11, A first polarizing member disposed on an outer surface of the first substrate; And And a second polarizing member disposed on an outer surface of the second substrate. delete delete 12. The method of claim 11, And a phase delay value of the phase delay unit is lambda / 2. 12. The method of claim 11, And a liquid crystal layer pattern having an isotropic phase is formed around the phase delay unit. 12. The method of claim 11, And a transmission pattern formed around the phase delay unit to transmit the phase of light as it is. 13. The method of claim 12, The first transmission axis of the first polarizing member and the second transmission axis of the second polarizing member are perpendicular to each other. 12. The method of claim 11, And a cell gap compensation pattern is further formed in the reflective region such that the cell gap of the transmission region is twice the cell gap of the reflective region. 12. The method of claim 11, And an alignment layer in which the alignment direction of the reflective region is the same as that of the transmission region. delete delete Forming an array element including a gate wiring and a data wiring crossing the first substrate and defining a pixel region having a transmissive region and a reflective region, and a thin film transistor connected to the gate wiring and the data wiring; Forming a reflecting plate in the reflecting region; Forming a first electrode connected to the thin film transistor and a second electrode alternately disposed with the first electrode in the pixel region; Attaching a second substrate facing the first substrate, and having a λ / 4 phase delay corresponding to the reflective region between the first substrate and the second substrate and a λ / 2 phase delay corresponding to the transmissive region; Forming a liquid crystal layer having; Providing a phase delay member having a phase delay portion corresponding to the reflection area; And Disposing the phase retardation member on an outer surface of the second substrate; Providing the phase delay member, Forming an alignment layer on the base substrate; Aligning the alignment layer; Forming a liquid crystal layer including photoreactive liquid crystal molecules on the alignment layer; Covering a mask exposing a region corresponding to the phase delay unit on the liquid crystal layer; Irradiating light onto the mask to cure the liquid crystal layer corresponding to the phase delay unit; Removing the liquid crystal layer under the mask to leave the cured liquid crystal layer pattern; And Forming a protective film on the substrate having the liquid crystal layer pattern formed thereon. Forming an array element including a gate wiring and a data wiring crossing the first substrate and defining a pixel region having a transmissive region and a reflective region, and a thin film transistor connected to the gate wiring and the data wiring; Forming a reflecting plate in the reflecting region; Forming a first electrode connected to the thin film transistor and a second electrode alternately disposed with the first electrode in the pixel region; Attaching a second substrate facing the first substrate, and having a λ / 4 phase delay corresponding to the reflective region between the first substrate and the second substrate and a λ / 2 phase delay corresponding to the transmissive region; Forming a liquid crystal layer having; Providing a phase delay member having a phase delay portion corresponding to the reflection area; And Disposing the phase retardation member on an outer surface of the second substrate; Providing the phase delay member, Forming an alignment layer on the base substrate; Aligning the alignment layer; Forming a liquid crystal layer including photoreactive liquid crystal molecules on the alignment layer; Covering a mask exposing a region corresponding to the phase delay unit on the liquid crystal layer; Irradiating light onto the mask to cure the liquid crystal layer corresponding to the phase delay unit; Removing the mask and heat treating the liquid crystal layer to phase-transfer the liquid crystal layer below the mask to an isotropic phase; And Photocuring the liquid crystal layer: a method of manufacturing a liquid crystal display device, characterized in that it comprises a. Forming an array element including a gate wiring and a data wiring crossing the first substrate and defining a pixel region having a transmissive region and a reflective region, and a thin film transistor connected to the gate wiring and the data wiring; Forming a reflecting plate in the reflecting region; Forming a first electrode connected to the thin film transistor and a second electrode alternately disposed with the first electrode in the pixel region; Attaching a second substrate facing the first substrate, and having a λ / 4 phase delay corresponding to the reflective region between the first substrate and the second substrate and a λ / 2 phase delay corresponding to the transmissive region; Forming a liquid crystal layer having; Providing a phase delay member having a phase delay portion corresponding to the reflection area; And Disposing the phase retardation member on an outer surface of the second substrate; Providing the phase delay member, Forming an alignment layer on the base substrate; Aligning the alignment layer; Forming a liquid crystal layer including photoreactive liquid crystal molecules on the alignment layer; Covering a mask exposing a region corresponding to the phase delay unit on the liquid crystal layer; Irradiating light onto the mask to cure the liquid crystal layer corresponding to the phase delay unit; Removing the liquid crystal layer under the mask to leave the cured liquid crystal layer pattern; Forming a transmissive layer through which a phase of light passes through the base substrate on which the liquid crystal layer pattern is formed; Forming a photoresist pattern exposing a region corresponding to the phase delay part on the transmission layer; And etching the transmission layer using the photoresist pattern as an etch mask to form a transmission pattern around the phase delay unit. 26. The method according to any one of claims 23 to 25, After forming the first electrode and the second electrode, And forming an alignment layer on the entire surface of the first substrate, the alignment layer having the same alignment direction as that of the reflective region and the transmission region. 26. The method according to any one of claims 23 to 25, The first transmission axis of the first polarizing member and the second transmission axis of the second polarizing member are perpendicular to each other.

Images