KR101433107B1 - A liquid crystal display device including a liquid crystal lens - Google Patents

Abstract

The present invention relates to an image display apparatus including a liquid crystal lens formed using a liquid crystal layer.

Specifically, the present invention provides a liquid crystal display comprising: a first substrate; A second substrate facing the first substrate and spaced apart from the first substrate; A first electrode formed on the inner surface of the first substrate; A plurality of second electrodes repeatedly formed on the inner surface of the second substrate, each of the second electrodes having a first opening each having a width corresponding to the first distance; A first liquid crystal layer formed between the first electrode and the plurality of second electrodes; A third substrate disposed under the first substrate; A fourth substrate spaced apart from and facing the third substrate and in contact with the first substrate; A pixel electrode formed on the inner surface of the third substrate; A fourth substrate; A second liquid crystal layer formed between the third substrate and the fourth substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate.

A liquid crystal display, a liquid crystal lens,

Description

[0001] The present invention relates to a liquid crystal display (LCD)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device including a liquid crystal lens, and more particularly, to a liquid crystal lens for driving a liquid crystal layer using three electrodes and a liquid crystal display device including the same.

Generally, a liquid crystal display device is composed of two opposing electrodes and a liquid crystal layer formed therebetween. The liquid crystal molecules of the liquid crystal layer are driven by an electric field generated by applying a voltage to the two electrodes. The liquid crystal molecules have a polarization property and an optical anisotropy. The polarization property means that when the liquid crystal molecules are placed in the electric field, the charges in the liquid crystal molecules collide with both sides of the liquid crystal molecules, and the molecular alignment direction changes according to the electric field. Refers to changing the path of the emitted light and the polarization state differently depending on the incident direction or polarization state of the incident light due to the elongated structure of the liquid crystal molecules and the aforementioned molecular arrangement direction.

Accordingly, the liquid crystal layer exhibits a difference in transmittance due to the voltage applied to the two electrodes, and the image can be displayed by varying the difference between the pixels.

Recently, a liquid crystal lens has been proposed in which the liquid crystal layer serves as a lens by taking advantage of the properties of such liquid crystal molecules.

That is, the lens controls the path of the incident light by using the refractive index difference between the material constituting the lens and the air, and positions the liquid crystal layer in different electric fields by applying different voltages to the liquid crystal layers The incident light incident on the liquid crystal layer experiences a different phase change according to the position, and as a result, the liquid crystal layer can control the path of the incident light like an actual lens.

Such a liquid crystal lens will be described with reference to the drawings.

1A and 1B are a perspective view and a cross-sectional view of a general liquid crystal lens, respectively.

1A and 1B, a general liquid crystal lens 10 includes a liquid crystal layer 40 (see FIG. 1) formed between first and second substrates 20 and 30 facing each other and a first and a second substrates 20 and 30, ). A first electrode 22 is formed on the entire inner surface of the first substrate 20 and a second electrode 32 spaced apart from the inner surface of the second substrate 30 by a distance d.

When a voltage is applied to the first and second electrodes 22 and 32, an electric field is formed between the two electrodes 22 and 32. When the second electrode 32 contacts the entire outer surface of the second substrate 30 The first and second substrates 20 and 30 are separated from each other so that a complete vertical electric field is not formed and a region substantially perpendicular to the first and second substrates 20 and 30 is formed in a region distant from the separation region 32a of the second electrode 32 An electric field is generated in the first and second substrates 20 and 30 in an area close to the separation section 32a of the second electrode 32. [

Accordingly, the electric field generated by the first and second electrodes 22 and 32 changes in intensity and direction according to the distance from the separation section 32a of the second electrode 32, and as a result, (40) also changes the phase of the incident light differently according to the distance from the separation section (32a) of the first and second electrodes (22, 32).

FIG. 2 is a graph showing the phase change of incident light when light passes through the liquid crystal lens of FIGS. 1A and 1B. FIG. 2 also shows the phase change when light passes through an actual lens for comparison.

2, the first, second, and third curves 40a, 40b, and 40c are curves showing the phase changes of light passing through the liquid crystal lenses of different configurations, and the fourth curve 40d is a curve It is a curve showing the phase change of the light passing through the lens. As can be seen from the first, second and third curves 40a, 40b and 40c, the phase change of the light passing through the liquid crystal lens is different from the phase difference of the second electrode (32 in Figs. 1A and 1B) Symmetrically about the center 32a of FIG.

For example, the first, second, and third curved lines 40a, 40b, and 40c are curved lines that gradually change the separation distance (d in FIGS. 1A and 1B) of the second electrode Even if the separation distance (Figs. 1A and 1B, d) is appropriately adjusted, there is a limit, so that the same result as the actual lens can not be obtained. That is, the first and second curved lines 40a and 40b have less phase change than the fourth curve 40d as a whole, while the third curve 40c has a larger phase change than the fourth curve 40d as a whole.

This result is attributable to the fact that the phase change control variable of the liquid crystal lens is small. The reason why the phase change can be controlled in the liquid crystal lens is that the distance between the second electrode (32 in Figs. 1A and 1B) d) and the second electrode (32 in Figs. 1A and 1B), it is difficult to obtain the same curvature as the phase change in the actual lens even if it is properly adjusted.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a liquid crystal lens and a liquid crystal display device including the same that can more freely control a phase change by driving a liquid crystal layer using three electrodes have.

The present invention also provides a liquid crystal display device including a liquid crystal lens capable of switching display of a two-dimensional plane image and a three-dimensional stereoscopic image under a reduced resolution by reducing the distance between the liquid crystal lens and the liquid crystal display panel There is a purpose.

According to an aspect of the present invention, there is provided a plasma display panel comprising: a first substrate; A second substrate facing the first substrate and spaced apart from the first substrate; A first electrode formed on the inner surface of the first substrate; A plurality of second electrodes repeatedly formed on the inner surface of the second substrate, each of the second electrodes having a first opening each having a width corresponding to the first distance; A first liquid crystal layer formed between the first electrode and the plurality of second electrodes; A third substrate disposed under the first substrate; A fourth substrate spaced apart from and facing the third substrate and in contact with the first substrate; A pixel electrode formed on the inner surface of the third substrate; A fourth substrate; A second liquid crystal layer formed between the third substrate and the fourth substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate.

On the other hand, the present invention provides a liquid crystal display comprising: a first substrate; Second and third substrates facing each other with the first substrate interposed therebetween; A first electrode formed on one surface of the first substrate facing the second substrate; A plurality of second electrodes repeatedly formed on the inner surface of the second substrate, each of the second electrodes having a first opening each having a width corresponding to the first distance; A first liquid crystal layer formed between the first electrode and the plurality of second electrodes; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the first substrate and the third substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate.

The liquid crystal display device of the present invention may further include a plurality of third electrodes repeatedly formed between the second electrode and the first liquid crystal layer and having second openings each having a width corresponding to the second distance .

At this time, the plurality of second electrodes and the plurality of third electrodes may be integrally formed into a rod shape.

Dimensional stereoscopic image when voltage is applied to the first electrode, the plurality of second electrodes, and the plurality of third electrodes, and displays the three-dimensional image on the first electrode, the plurality of second electrodes, Dimensional image when the voltage is not applied to the third substrate, the pixel electrodes are formed on the inner surface of the third substrate to be spaced apart from each other to define a plurality of image pixels, and the liquid crystal display device displays the three- The plurality of image pixels alternately display the first and second images.

Also, when the liquid crystal display displays the three-dimensional image, the first liquid crystal layer changes the optical path for the selected one polarized light and does not change the optical path for the other polarized light.

A liquid crystal display device includes a first alignment layer formed between the first electrode and the liquid crystal layer; A second alignment layer formed between the third electrode and the liquid crystal layer; And an insulating layer formed between the second electrode and the third electrode.

A first voltage, a second voltage, and a third voltage are applied to the first electrode, the plurality of second electrodes, and the plurality of third electrodes, respectively, and at least one of the first, second, In particular, the first voltage may be a direct current voltage, and the second and third voltages may be alternating voltages having the same magnitude and different magnitude.

The first distance may be smaller than the second distance.

According to another embodiment of the present invention, there is provided a plasma display panel comprising: a first substrate; A second substrate facing the first substrate and spaced apart from the first substrate; A first electrode formed on the inner surface of the first substrate; A second electrode formed on the inner surface of the second substrate; An insulating layer formed on the second electrode and having a semi-cylindrical recessed concave portion; A first liquid crystal layer formed between the first electrode and the insulating layer to fill the concave portion; A third substrate disposed under the first substrate; A fourth substrate spaced apart from and facing the third substrate and in contact with the first substrate; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the third substrate and the fourth substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate.

According to another embodiment of the present invention, there is provided a plasma display panel comprising: a first substrate; A second substrate spaced apart from and facing the first substrate above the first substrate; A first electrode in the form of a plate formed on an upper surface of the first substrate; A second electrode in the form of a plate formed on a lower surface of the second substrate; An insulating layer formed on the second electrode and having a semi-cylindrical recessed concave portion; A first liquid crystal layer formed between the first electrode and the insulating layer to fill the concave portion; A third substrate spaced apart from and facing the first substrate and contacting the first substrate; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the first substrate and the third substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate.

In this case, the insulating layer has a refractive index equal to a long axis refractive index of the liquid crystal molecules constituting the first liquid crystal layer, and the liquid crystal constituting the first liquid crystal layer has a vertical orientation or a horizontal orientation characteristic .

A first alignment layer may be formed between the first electrode and the first liquid crystal layer, and a second alignment layer may be further formed between the insulating layer having the recess and the first alignment layer.

And the first electrode and the second electrode are formed on the entire surface of the first substrate and the second substrate, respectively, in the form of a plate.

In the case of including four substrates among all the liquid crystal display devices according to the present invention, a common electrode may be further formed on the inner surface of the fourth substrate, and the second liquid crystal layer may be formed between the pixel electrode and the common electrode .

In the case of including three substrates among all the liquid crystal display devices according to the present invention, a common electrode is further formed on one surface of the first substrate facing the third substrate, And may be formed between the common electrodes.

The liquid crystal lens according to the present invention is a liquid crystal display device in which an electric field is generated by using three electrodes and the liquid crystal layer is driven by the electric field or an insulating layer having two plate electrodes and semi-cylindrical recesses and a liquid crystal layer And an electric field is generated by the plate-shaped electrode to drive the semi-cylindrical liquid crystal layer. Thus, a liquid crystal lens substantially identical to the optical lens can be realized. In the liquid crystal display device according to the present invention including such a liquid crystal lens, Dimensional image and a three-dimensional image by switching the voltage applied to the liquid crystal lens.

In addition, the distance between the liquid crystal lens and the liquid crystal display panel can be minimized, and the three-dimensional stereoscopic image can be smoothly displayed under high resolution.

The first and second polarizing plates are disposed on the outer surface of the substrate located at the outermost periphery of the liquid crystal display panel and the liquid crystal lens, respectively, so that the path of the light incident on the liquid crystal lens by the diffusion action of the polarizing plate is shifted to the outside of the display region There is an effect of preventing display quality deterioration that occurs due to the above.

Further, the manufacturing cost can be reduced by manufacturing the liquid crystal lens and the liquid crystal display panel using three substrates in total.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

≪ Embodiment 1 >

3 is a cross-sectional view schematically showing a liquid crystal lens according to a first embodiment of the present invention.

3, the liquid crystal lens 110 according to the first embodiment of the present invention includes first and second substrates 120 and 130 and first and second substrates 120 and 130 (Not shown). A first electrode 122 is formed on the inner surface of the first substrate 120 and a first alignment layer 124 is formed on the first electrode 122.

A second electrode 132 having a first opening with a width corresponding to the first distance d1 is formed on the inner surface of the second substrate 130 with the center of the second substrate 130 as a center, An insulating film 134 is formed under the electrode 132. A third electrode 136 having a second opening portion having a width corresponding to the second distance d2 is formed on the lower portion of the insulating layer 134 with the center of the second substrate 130 as a center, A second alignment film 138 is formed. The second and third electrodes 132 and 136 are electrically insulated from each other by the insulating film 134, and are disposed so as to partially overlap each other. Although not shown, the second and third electrodes 132 and 136 may be connected to each other at the ends of the first and second openings in plan view.

A liquid crystal layer 140 is formed between the first and second alignment layers 124 and 138. In a particular case, the first and second alignment layers 124 and 138 may be omitted. In this embodiment, the second alignment layer 138 is formed in contact with the third electrode 136, but in other embodiments, a protective layer of an insulating material may be formed between the third electrode 136 and the second alignment layer 138 have. Also, the first, second, and third electrodes 122, 132, and 136 may be made of a transparent conductive material.

In the liquid crystal lens 110 having such a structure, an electric field is generated by the first, second and third voltages respectively applied to the first, second and third electrodes 122, 132 and 136, Is driven. The generated electric field is controlled by the magnitude of the first, second and third voltages and the magnitude and direction of the first and second distances d1 and d2. Can be generated more finely.

The diversity of the size and direction of the generated electric field according to the position means a variety of phase change curves in the liquid crystal layer 140. The first, second and third voltages and the first and second distances d1 and d2 are appropriately adjusted Thereby realizing substantially the same phase change curve as in the actual lens. That is, in the liquid crystal lens 110 according to the first embodiment of the present invention, the refractive index of the liquid crystal layer 140 is finely adjusted by the generated electric field, and accordingly, The phase change exhibits the same light path changing effect as that of the actual lens.

The first, second, and third voltages applied to the first, second, and third electrodes may be voltages having different sizes, and may be a direct current (DC) voltage or alternating current (AC) Lt; / RTI > When the electric field of the DC voltage is continuously applied to the liquid crystal layer 140, the liquid crystal layer 140 may be deteriorated due to accumulation of charges in one direction. Therefore, at least one of the first, second, It is preferable that it is an AC voltage. For example, a DC voltage may be applied to the first electrode 122 and an AC voltage of a different magnitude may be applied to the second and third electrodes 132 and 136 at the same frequency.

In this embodiment, the first distance d1 is smaller than the second distance d2, but in other embodiments, the first distance d1 may be greater than or equal to the second distance d2 as necessary.

Since the liquid crystal lens functions as a lens or acts as a simple transmission layer depending on the presence or absence of a voltage applied to the electrodes, the liquid crystal lens can be applied to a liquid crystal display panel so that a two-dimensional plane image and a three- .

≪ Embodiment 2 >

4 is a cross-sectional view of a liquid crystal display device including a liquid crystal lens according to a second embodiment of the present invention. The liquid crystal lens of Fig. 4 will not be described in the same manner as the liquid crystal lens of Fig.

4, the liquid crystal display device 201 according to the second embodiment of the present invention includes a liquid crystal lens 210 and a liquid crystal display panel 250 formed below the liquid crystal lens 210. As shown in FIG.

The liquid crystal lens 210 includes first and second substrates 220 and 230 spaced apart from each other and a first liquid crystal layer 240 formed between the first and second substrates 220 and 230. A first electrode 222 is formed on the inner surface of the first substrate 220 and a first alignment layer 224 is formed on the first electrode 222.

A plurality of second electrodes 232 having a first opening with a width corresponding to the first distance d1 are repeatedly formed on the inner surface of the second substrate 230 and a plurality of second electrodes 232 are repeatedly formed, And an insulating film 234 is formed on the bottom. A plurality of third electrodes 236 are repeatedly formed under the insulating layer 234 and each having a second opening having a width corresponding to the second distance d2. (Not shown). The plurality of second electrodes and the plurality of third electrodes 232 and 236 are electrically insulated from each other by the insulating film 234, and are arranged to partially overlap each other. Although not shown, the second electrode 232 and the third electrode 236 formed in one unit liquid crystal lens (ULL) may be in the form of a rod extending in a direction perpendicular to the drawing in plan view, And may be connected at the ends of the second openings.

3, the liquid crystal lens 210 functions as a single lens by applying a voltage to each electrode. The liquid crystal lens 210 includes a first electrode 222, a pair of second electrodes 232, (236) constitute one unit liquid crystal lens (ULL). In other words, by applying first, second, and third voltages to the first electrode 222, the pair of second electrodes 232, and the pair of third electrodes 236, the unit liquid crystal lens ULL is divided into one cylindrical lens and the entire liquid crystal lens 210 functions as a plurality of connected cylindrical lenses.

Although the second and third electrodes 232 and 236 are shown as being separated by each unit liquid crystal lens ULL in FIG. 4, if the unit liquid crystal lens ULL is designed to have the same optical characteristics such as a refractive index, Since the same voltage is applied to each of the second and third electrodes 232 and 236 of the unit liquid crystal lens ULL, the second and third electrodes 232 and 236 of the adjacent unit liquid crystal lens ULL are integrally formed .

An electric field is generated by the first, second, and third voltages applied to the first, second, and third electrodes 222, 232, and 236, respectively, and the first liquid crystal layer 240 is driven by the generated electric field. The generated electric field is adjusted in magnitude and direction according to the magnitude of the first, second and third voltages and the first and second distances d1 and d2. As a result, the phase change curve in the first liquid crystal layer 240 The shape is adjusted.

The first, second and third voltages may be voltages having different sizes and may be a direct current (DC) voltage or an alternating current (AC) voltage, and at least one of the first, second and third voltages is an alternating voltage desirable. For example, a DC voltage may be applied to the first electrode 222 and an AC voltage of a different magnitude may be applied to the second and third electrodes 232 and 236 at the same frequency.

The liquid crystal display panel 250 includes third and fourth substrates 260 and 270 spaced apart from each other and a second liquid crystal layer 280 formed between the third and fourth substrates 260 and 270. A pixel electrode 262 is formed on the inner surface of the third substrate 260 in correspondence with each of the image pixels P 1 and P 2 and a common electrode 272 is formed on the inner surface of the second substrate 270. The second liquid crystal layer 280 is formed between the pixel electrode 262 and the common electrode 272 and changes the polarization state and transmittance of the incident light according to the voltage applied to the pixel electrode 262 and the common electrode 272 Display the image.

Accordingly, first and second polarizers 292 and 294 are formed on the outer surfaces of the third and fourth substrates 260 and 270, respectively. The polarizing axes of the first and second polarizing plates 292 and 294 may be orthogonal to each other and the polarizing state of the incident light incident on the first polarizing plate 292 may be changed according to the voltage applied to the second liquid crystal layer 280 And determines whether the second polarizing plate 292 has passed or not, thereby displaying an image.

The first and second image pixels P1 and P2 are sequentially and repeatedly arranged on the liquid crystal display panel 250 to display the first and second images IM1 and IM2, respectively.

When the first, second, and third voltages are applied to the first, second, and third electrodes 222, 232, and 236 so that the liquid crystal lens 210 functions as an optical lens, The two images IM1 and IM2 are transmitted to the first and second viewing zones VZ1 and VZ2 by the liquid crystal lens 210, respectively. If the distance between the first and second viewing zones VZ1 and VZ2 is designed to be a distance between two eyes of a person, the user can select the first and second images VZ1 and VZ2 respectively transmitted to the first and second viewing zones VZ1 and VZ2 IM1, and IM2) are synthesized to recognize a stereoscopic 3D image.

If the first, second, and third voltages are not applied to the first, second, and third electrodes 222, 232, and 236 so that the liquid crystal lens 210 functions as a simple transparent layer, And the second images IM1 and IM2 pass through the liquid crystal lens 210 without refraction. Accordingly, the first and second images IM1 and IM2 are transmitted to the user as they are without any time-of-sight, and the user recognizes the two-dimensional image.

 Consequently, the liquid crystal display device including the liquid crystal lens according to the second embodiment of the present invention can switch the two-dimensional plane image and the three-dimensional image according to the presence or absence of the voltage applied to each electrode of the liquid crystal lens.

Although not shown in FIG. 4, the liquid crystal display panel 250 includes a gate wiring and a data wiring crossing each other between the third substrate 260 and the pixel electrode 262, and a thin film transistor connected to the gate wiring and the data wiring are formed And the thin film transistor may be connected to the pixel electrode 262 to switch the voltage applied to the pixel electrode. Between the fourth substrate 270 and the common electrode 272, a black matrix corresponding to the gate wiring and the data wiring, and a color filter layer below the black matrix may be formed. Third and fourth alignment layers may be formed between the pixel electrode 262 and the second liquid crystal layer 280 and between the common electrode 272 and the second liquid crystal layer 280.

However, since the pixels of the liquid crystal display panel are reduced in size in accordance with the trend of higher resolution, the first and second image pixels P1 and P2, which respectively represent the first and second images IM1 and IM2, ), That is, the pitch of image pixels is also reduced. However, since the binocular parallax of a human being is constant at about 65 mm, in order to smoothly display a three-dimensional stereoscopic image with a liquid crystal display having a distance between the reduced first and second image pixels P1 and P2, (L1: distance between the center plane of the first liquid crystal layer and the center plane of the second liquid crystal layer) between the liquid crystal display panels 250 must also be reduced.

The first distance L1 between the liquid crystal lens 210 and the liquid crystal display panel 250 should be about 0.5 mm when the pitch of the image pixels of the liquid crystal display panel 250 is about 50 m, 2 images (IM1, IM2) can be smoothly separated and a three-dimensional stereoscopic image can be displayed.

The main factors determining the first distance L1 between the liquid crystal lens 210 and the liquid crystal display panel 250 are the thickness of the first substrate 220, the second polarizer 294, and the fourth substrate 270 Even if the thickness of each substrate is reduced, a polarizing plate having a thickness of about 2 mm can be a stumbling block.

Hereinafter, a liquid crystal display device provided by the present invention will be described in order to solve such a problem.

≪ Third Embodiment >

5 is a cross-sectional view of a liquid crystal display device including a liquid crystal lens according to a third embodiment of the present invention. The description of the same components as those of the liquid crystal lens of Fig. 3 with respect to the liquid crystal lens of Fig. 5 is omitted.

5, the liquid crystal display device 360 according to the third embodiment of the present invention is composed of a liquid crystal lens 310 and a liquid crystal display panel 350 which is disposed in contact with the liquid crystal lens 310 at a lower portion thereof .

The liquid crystal lens 310 includes first and second substrates 320 and 330 spaced apart from each other and a first liquid crystal layer 340 formed between the first and second substrates 320 and 330. A first electrode 322 is formed on the inner surface of the first substrate 320 and a first alignment layer 324 is formed on the first electrode 322.

A plurality of second electrodes 332 are repeatedly formed on the inner surface of the second substrate 330 and each have a first opening having a width corresponding to the first distance d1. And an insulating film 334 is formed on the bottom. A plurality of third electrodes 336 are repeatedly formed under the insulating layer 334 and each having a second opening having a width corresponding to the second distance d2. (Not shown). The plurality of second electrodes and the plurality of third electrodes 332 and 336 are electrically insulated from each other by the insulating film 334 and are arranged so as to partially overlap each other. Although not shown, the second electrode 332 and the third electrode 336 may have a rod shape extending in a direction perpendicular to the drawing, and may be connected to the ends of the first and second openings, respectively.

3, the liquid crystal lens 310 functions as a single lens by applying a voltage to each electrode. The liquid crystal lens 310 includes a first electrode 322, a pair of second electrodes 332, (336) constitute one unit liquid crystal lens (ULL). The unit liquid crystal lens ULL is formed by applying the first, second, and third voltages to the first electrode 322, the pair of second electrodes 332, and the pair of third electrodes 336, and the entire liquid crystal lens 310 functions as a plurality of connected cylindrical lenses.

Although the second and third electrodes 332 and 336 are shown as being separated for each unit liquid crystal lens ULL in FIG. 5, if the unit liquid crystal lenses ULL are designed to have the same optical characteristics such as the refractive index Since the same voltage is applied to the second and third electrodes 332 and 336 of each unit liquid crystal lens ULL, the second and third electrodes 332 and 336 of the adjacent unit liquid crystal lens ULL are integrally connected .

An electric field is generated by the first, second, and third voltages applied to the first, second, and third electrodes 322, 332, and 336, respectively, and the first liquid crystal layer 340 is driven by the generated electric field. The generated electric field is adjusted in magnitude and direction according to the magnitude of the first, second and third voltages and the first and second distances d1 and d2. As a result, the phase change curve in the first liquid crystal layer 340 The shape is adjusted.

The first, second and third voltages may be voltages having different sizes and may be a direct current (DC) voltage or an alternating current (AC) voltage, and at least one of the first, second and third voltages is an alternating voltage desirable. For example, a DC voltage may be applied to the first electrode 322 and an AC voltage of a different magnitude may be applied to the second and third electrodes 332 and 336 at the same frequency.

The liquid crystal display panel 350 includes third and fourth substrates 360 and 370 spaced apart from each other and a second liquid crystal layer 380 formed between the third and fourth substrates 360 and 370. A pixel electrode 362 is formed on the inner surface of the third substrate 360 and a common electrode 372 is formed on the inner surface of the fourth substrate 370. The second liquid crystal layer 380 is formed between the pixel electrode 362 and the common electrode 372 and changes the polarization state and transmittance of the incident light according to the voltage applied to the pixel electrode 362 and the common electrode 372 Display the image.

The first substrate 320 of the liquid crystal lens 310 and the fourth substrate 370 of the liquid crystal display panel 350 are brought into contact with each other to minimize the distance between the liquid crystal lens 310 and the liquid crystal display panel 350 And the first and second polarizing plates 392 and 394 necessary for image display of the liquid crystal display panel 350 are formed on the outer surfaces of the third and second substrates 360 and 330, respectively.

As a result, the second spacing distance L2 between the liquid crystal lens 310 and the liquid crystal display panel 350 of the liquid crystal display device 360 according to the third embodiment of the present invention, (L1 in Fig. 4) between the liquid crystal lens (210 in Fig. 4) and the liquid crystal display panel (250 in Fig. 4) of the display device ), It is possible to smoothly express the three-dimensional stereoscopic image.

The polarizing axes of the first and second polarizing plates 392 and 394 may be orthogonal to each other and the polarizing state of the incident light incident on the first polarizing plate 392 may be changed depending on the applied voltage And determines whether the second polarizing plate 392 has passed or not, thereby displaying an image.

The liquid crystal display panel 350 sequentially and repeatedly arranges the first and second image pixels P1 and P2 for displaying the first and second images, respectively.

When the first, second, and third voltages are applied to the first, second, and third electrodes 322, 332, and 336 so that the liquid crystal lens 310 functions as an optical lens, 2 images are transmitted to the first and second view areas respectively by the liquid crystal lens 310 and the distance between the first and second view areas is designed as a distance between two eyes of a person, And the first and second images, which are respectively transmitted, are synthesized to recognize a stereoscopic three-dimensional image.

If the first, second, and third voltages are not applied to the first, second, and third electrodes 322, 332, and 336 so that the liquid crystal lens 310 functions as a simple transparent layer, And the second image passes through the liquid crystal lens 310 as it is without refraction, and is transmitted to the user as it is without distinction of view area, and the user recognizes the two-dimensional image.

 As a result, the liquid crystal display device including the liquid crystal lens according to the third embodiment of the present invention can switch between two-dimensional plane images and three-dimensional stereoscopic images according to the presence or absence of a voltage applied to each electrode of the liquid crystal lens.

Although not shown in FIG. 5, the liquid crystal display panel 350 includes a gate wiring and a data wiring crossing each other between the third substrate 360 and the pixel electrode 362, and a thin film transistor connected to the gate wiring and the data wiring are formed And the thin film transistor may be connected to the pixel electrode 362 to switch the voltage applied to the pixel electrode. Between the fourth substrate 370 and the common electrode 372, a black matrix corresponding to the gate wiring and the data wiring and a color filter layer under the black matrix can be formed. The third and fourth alignment layers may be formed between the pixel electrode 362 and the second liquid crystal layer 380 and between the common electrode 372 and the second liquid crystal layer 380.

Next, a liquid crystal display device provided by the present invention which can more smoothly display a three-dimensional stereoscopic image in response to an increased resolution will be described.

<Fourth Embodiment>

6 is a cross-sectional view of a liquid crystal display device including a liquid crystal lens according to a fourth embodiment of the present invention. The liquid crystal lens of Fig. 6 is omitted from the description of the same parts as those of the liquid crystal lens of Fig.

6, the liquid crystal display device 460 according to the fourth embodiment of the present invention is constituted by a liquid crystal lens 410 and a liquid crystal display panel 450 constituted integrally with the liquid crystal lens 410 at the lower part thereof do. That is, the liquid crystal display device 460 includes a first substrate 420, second and third substrates 430 and 460 facing each other with the first substrate 420 interposed therebetween, A first liquid crystal layer 440 between the first and third substrates 420 and 430 and a second liquid crystal layer 480 between the first and third substrates 420 and 460, 410 and the liquid crystal display panel 450 as well.

The liquid crystal lens 410 includes first and second substrates 420 and 430 spaced apart from each other and a first liquid crystal layer 440 formed between the first and second substrates 420 and 430. A first electrode 422 is formed on the entire surface between the first substrate 420 and the first liquid crystal layer 440 and a first alignment layer 424 is formed on the first electrode 422.

A plurality of second electrodes 432 are repeatedly formed on the inner surface of the second substrate 430 and each have a first opening having a width corresponding to the first distance d1. And an insulating film 434 is formed on the bottom. A plurality of third electrodes 436 are repeatedly formed under the insulating layer 434 and each having a second opening having a width corresponding to the second distance d2. (Not shown). The plurality of second electrodes and the plurality of third electrodes 432 and 436 are electrically insulated from each other by the insulating film 434, and are arranged to partially overlap each other. Although not shown, the second electrode 432 and the third electrode 436 may have a rod shape extending in a direction perpendicular to the drawing, and may be connected to the ends of the first and second openings, respectively.

3, the liquid crystal lens 410 functions as a single lens by applying a voltage to each electrode. The liquid crystal lens 410 includes a first electrode 422, a pair of second electrodes 4332, (436) constitute one unit liquid crystal lens (ULL). The unit liquid crystal lens ULL is formed by applying the first, second, and third voltages to the first electrode 422, the pair of second electrodes 432, and the pair of third electrodes 436, and the entire liquid crystal lens 410 functions as a plurality of connected cylindrical lenses.

Although the second and third electrodes 432 and 436 are shown as being separated by each unit liquid crystal lens ULL in FIG. 5, the unit liquid crystal lenses ULL are designed such that the optical characteristics such as the refractive index of the unit liquid crystal lenses ULL are the same The same voltage is applied to the second and third electrodes 432 and 436 of each unit liquid crystal lens ULL so that the second and third electrodes 432 and 436 of the adjacent unit liquid crystal lens ULL are connected to each other As shown in FIG.

An electric field is generated by the first, second, and third voltages applied to the first, second, and third electrodes 422, 432, and 436, respectively, and the first liquid crystal layer 440 is driven by the generated electric field. The generated electric field is adjusted in magnitude and direction according to the magnitude of the first, second and third voltages and the first and second distances d1 and d2. As a result, the phase change curve in the first liquid crystal layer 440 The shape is adjusted.

The first, second and third voltages may be voltages having different sizes and may be a direct current (DC) voltage or an alternating current (AC) voltage, and at least one of the first, second and third voltages is an alternating voltage desirable. For example, a DC voltage may be applied to the first electrode 422 and an AC voltage of a different magnitude may be applied to the second and third electrodes 432 and 436 at the same frequency.

The liquid crystal display panel 450 includes third and fourth substrates 460 and 420 spaced apart from each other and a second liquid crystal layer 480 formed between the third and first substrates 460 and 420. A pixel electrode 462 is formed on the inner surface of the third substrate 460 in correspondence with each of the image pixels P1 and P2 and a common electrode 472 is formed between the first substrate 420 and the second liquid crystal layer 480, Respectively. The second liquid crystal layer 480 is formed between the pixel electrode 462 and the common electrode 472 and changes the polarization state and transmittance of the incident light according to the voltage applied to the pixel electrode 462 and the common electrode 472 Display the image.

In order to minimize the distance between the liquid crystal lens 410 and the liquid crystal display panel 450, the first substrate 420 is a component of the liquid crystal lens 410 and a component of the liquid crystal display panel 450, The first and second polarizing plates 492 and 494 necessary for image display of the panel 450 are formed on the outer surfaces of the third and fourth substrates 460 and 430, respectively.

As a result, the third distance L3 between the liquid crystal lens 410 and the liquid crystal display panel 450 of the liquid crystal display device 460 according to the fourth embodiment of the present invention is smaller than the third distance L3 between the liquid crystal display device 460 and the liquid crystal display panel 450, 5) of the display device (301 in Fig. 5) and the liquid crystal display panel (350 in Fig. 5) of the liquid crystal display panel Three-dimensional images can be displayed more smoothly.

The polarizing axes of the first and second polarizing plates 492 and 494 may be orthogonal to each other and the polarizing state of the incident light incident on the first polarizing plate 492 may be changed depending on the applied voltage And determines whether the second polarizing plate 492 has passed or not, thereby displaying an image.

The first and second image pixels P1 and P2, which respectively display the first and second images, are sequentially and repeatedly arranged on the liquid crystal display panel 450. [

When the first, second and third voltages are applied to the first, second and third electrodes 422, 432 and 436 and the liquid crystal lens 410 functions as an optical lens, 2 images are transmitted to the first and second view areas respectively by the liquid crystal lens 410 and the distance between the first and second view areas is designed as a distance between two eyes of a person, The first and second images, which are respectively transmitted, are synthesized to recognize a stereoscopic 3D image.

When the first, second, and third voltages are not applied to the first, second, and third electrodes 422, 432, and 436 so that the liquid crystal lens 410 functions as a simple transparent layer, And the second image passes through the liquid crystal lens 410 without being refracted, and is transmitted to the user without any distinction of view area, and the user recognizes the two-dimensional image.

 Consequently, the liquid crystal display device including the liquid crystal lens according to the fourth embodiment of the present invention can switch between a two-dimensional plane image and a three-dimensional image according to the presence or absence of a voltage applied to each electrode of the liquid crystal lens.

Although not shown in FIG. 6, the liquid crystal display panel 450 has gate lines and data lines crossing each other between the third substrate 460 and the pixel electrodes 462, and thin film transistors connected to the gate lines and the data lines are formed And the thin film transistor may be connected to the pixel electrode 462 to switch the voltage applied to the pixel electrode. Between the first substrate 420 and the common electrode 472, a black matrix corresponding to the gate wiring and the data wiring, and a color filter layer under the black matrix may be formed. Third and fourth alignment layers may be formed between the pixel electrode 462 and the second liquid crystal layer 480 and between the common electrode 472 and the second liquid crystal layer 480.

Next, the operation of the liquid crystal display device including the liquid crystal lens according to the fourth embodiment of the present invention will be described with reference to the polarization state of incident light.

FIGS. 7A and 7B are schematic views showing the optical path and polarization state of incident light when the liquid crystal lens of the liquid crystal display device according to the fourth embodiment of the present invention is in the off-state and the on-state, respectively. 7A and 7B show only the polarizing plate and the liquid crystal layer, which are optical elements that affect the optical path and polarization state of the incident light among the components of the liquid crystal display device.

7A and 7B, the off-state of the liquid crystal lens (410 in Fig. 6) (the case where the liquid crystal lens functions as a simple transparent layer is in an off state, and the case in which the liquid crystal lens functions as an optical lens is defined as an on state) The incident light emitted from a backlight (not shown) under the liquid crystal display panel 450 of FIG. 6 passes through the first polarizing plate 492 and becomes a first polarized light and enters the second liquid crystal layer 480 do.

The polarized state of the first polarized light (ⓧ) passes through the second liquid crystal layer 480 and changes in accordance with the off and on states of the liquid crystal display panel (450 in FIG. 6). The liquid crystal display panel 450 When no voltage is applied to the pixel electrode (462 in FIG. 6) and the common electrode (472 in FIG. 6) in the normally black mode, a black image is displayed, 6, 462) and the common electrode (472 of FIG. 6), a white image is displayed.

That is, when the incident light which is the first polarized light passes through the second liquid crystal layer 480 corresponding to the image pixel for displaying the black image, the first polarized light (ⓧ) is outputted as it is without changing the polarization state, And the second polarized light (?) Is emitted when the polarized light passes through the second liquid crystal layer 480 corresponding to the image pixel representing the first polarized light.

In addition, since the outgoing light of the backlight does not change in the optical path while passing through the first polarizer 492 and the second liquid crystal layer 480, the outgoing light of the backlight goes straight and passes through the second liquid crystal layer 480 .

The outgoing light of the liquid crystal display panel (450 of FIG. 6) then passes through the first liquid crystal layer 440 and the second polarizing plate 494 of the liquid crystal lens (410 of FIG. 6) (410 in Fig. 6), which are different from each other depending on the off-state and the on-state of the lens (410 in Fig. 6).

As shown in FIG. 7A, when the liquid crystal lens (410 in FIG. 6) is in an off state, the first liquid crystal layer 440 simply functions as a transparent layer with respect to incident light in all polarization states, The first and second polarized lights (x, y) emitted from the second liquid crystal layer 480 of the first liquid crystal layer 480 pass through the first liquid crystal layer 440 without changing the optical path and the polarization state and reach the second polarizer plate 494 do.

Since the second polarizing plate 494 has a polarization axis different from that of the first polarizing plate 492, the first polarized light among the outgoing light of the first liquid crystal layer 440 of the liquid crystal lens (410 of FIG. 6) And the second polarized light (?) Passes through the second polarizer 494 to display a white image. At this time, since the first and second polarized lights do not change the optical path, they can not generate separate viewing areas. Therefore, when the liquid crystal lens (461 in Fig. 6) is in the off state, the liquid crystal display The image is displayed.

On the other hand, as shown in FIG. 7B, when the liquid crystal lens (410 in FIG. 6) is in the ON state, the first liquid crystal layer 440 serves as an optical lens according to the polarization state of the incident light.

Namely, the polarized light selected from the incident light of the liquid crystal lens (410 in FIG. 6) serves as an optical lens for changing the optical path and serves as a simple transparent layer which does not change the optical path for the other polarized light.

Here, the incident light of the liquid crystal lens (410 in FIG. 6) serves as an optical lens for the second polarized light and serves as a simple transparent layer for the other polarized light. However, in other embodiments, the first liquid crystal layer 440) can be designed.

Accordingly, the first polarized light (ⓧ) passes through the first liquid crystal layer 440 without changing the optical path and the polarization state, and reaches the second polarizing plate 494 as it is, while the polarized state of the second polarized light (↔) But the light path is changed to reach the second polarizing plate 494.

Since the second polarizing plate 494 has a polarization axis different from that of the first polarizing plate 492, the first polarized light among the outgoing light of the first liquid crystal layer 440 of the liquid crystal lens (410 of FIG. 6) The second polarized light (↔) having the changed optical path passes through the second polarizer 494 to display a white image. At this time, the first polarized light (ⓧ) is a component that does not contribute to the field of view because the optical path is not changed, but is blocked by the second polarizer 494, so that it does not interfere with the three-dimensional image display of the liquid crystal display device, When the liquid crystal lens (461 in FIG. 6) is in an on state, the liquid crystal display (460 in FIG. 6) is in a state of being in a three-dimensional solid state The image is displayed.

Although the liquid crystal display panel (450 in FIG. 6) is described as being in the normally black mode in the above embodiment, even when the liquid crystal display panel (450 in FIG. 6) is in the normally white mode The liquid crystal display device (460 of FIG. 6) switches the two-dimensional flat image and the three-dimensional stereoscopic image and displays the two-dimensional flat image and the three-dimensional stereoscopic image by the same operation except that the luminance of the displayed image and whether or not the voltage is applied is opposite to the normally black mode. can do.

The liquid crystal display device 301 shown in Fig. 5 is formed by forming the liquid crystal lens 310 and the liquid crystal display panel 350 and then attaching the first and fourth substrates 320 and 370 using an adhesive or the like The liquid crystal display device 401 shown in FIG. 6 may have first and second electrodes 422 and 472 formed on both sides of the first substrate 420 and a second and a third electrode 432 The third substrate 460 on which the pixel electrode 462 is formed after the second substrate 430 on which the first liquid crystal layer 436 is formed is bonded to the first substrate 420 through the first liquid crystal layer 440, (480), or the second and third substrates (430, 460) can be formed in a different order.

<Fifth Embodiment>

8 is a cross-sectional view of a liquid crystal display device including a liquid crystal lens according to a fifth embodiment of the present invention.

First, the liquid crystal lens used in the fifth embodiment of the present invention will be described.

The liquid crystal lens 510 used in the liquid crystal display device 501 according to the fifth embodiment of the present invention is not required to constitute a plurality of spaced electrodes as in the first to fourth embodiments, A plurality of semicylindrical first liquid crystal layers 540 exposed to the vertical electric field are formed by forming first and second electrodes 522 and 537 and applying a voltage to the two electrodes 522 and 537 to form a vertical electric field, And it functions as a lenticular lens having a simple semi-cylindrical convex portion.

That is, in the liquid crystal lens according to the first to fourth embodiments, the liquid crystal layer forming the lens has a plate shape, and the plate-shaped liquid crystal layer is formed by a plurality of electrodes having a predetermined spacing therebetween at the upper portion or the lower portion. The liquid crystal lens 510 according to the fifth embodiment of the present invention has a plurality of semicylindrical concave portions made of a transparent material as the first liquid crystal layer 540 itself serving as a lens The upper surface of the first substrate 520 positioned below the upper surface of the first substrate 520 is flat and the upper surface of the first substrate 520 is covered with a plurality of convex semi- . The refractive index of the insulating layer 539 having a plurality of semicylindrical concave portions has the same value as the refractive index in the major axis direction of the liquid crystal molecules constituting the first liquid crystal layer 540.

At this time, a first alignment layer 524 in the form of a flat plate is formed on the lower portion of the first liquid crystal layer 540 having a plurality of semicylindrical shapes, and a plurality of semi- And a second alignment film 538 is further formed in a cylindrical shape.
Here, the ends of each of the plurality of recesses are brought into contact with the first alignment film 524 (E).

A first electrode 522 is formed on the entire surface of the first alignment layer 524 to have a plate shape and a transparent electrode 522 is formed on the entire surface of the first alignment layer 524. The upper portion of the insulation layer 539 having the concave portion corresponds to the first electrode 522 And a second electrode 537 in the form of a plate is formed on the entire surface in the same manner as the first electrode 522.

A first substrate 520 is formed of a transparent material and a second substrate 530 is formed of a transparent material on the second electrode 537 under the first electrode 522.

The liquid crystal lens 510 used in the liquid crystal display device according to the fifth embodiment of the present invention includes the first substrate 510 between the first substrate 520 and the second substrate 530 facing each other, A first alignment layer 524 in the form of a plate, a first liquid crystal layer 540 having a plurality of semicylindrical shapes, and a plurality of second alignment layers 524 for capturing the first liquid crystal layer An insulating layer 539 having a semi-cylindrical concave portion and having a specific refractive index (a refractive index in the major axis direction of the liquid crystal molecules constituting the first liquid crystal layer 540), a plurality of semi-cylindrical shaped second orientation films 538 And a second electrode 537 in the form of a plate are stacked.

The operation of the liquid crystal lens 510 according to the fifth embodiment having such a configuration will be described with reference to Figs. 9A and 9B showing the change of the first liquid crystal layer when the power is turned on / off . In this case, when the first and second electrodes 522 and 537 are not applied with voltage, the liquid crystal that constitutes the first liquid crystal layer 540 has a horizontal alignment in which the long axes thereof are arranged parallel to the first alignment layer 540 Or a liquid crystal having a vertical alignment characteristic in which the major axis of the first alignment layer 540 is vertically aligned with respect to the first alignment layer 540.

In the drawing, a horizontally aligned liquid crystal having a characteristic in which long axes thereof are arranged in parallel with the first alignment layer 540 when no voltage is applied is used, and the insulating layer 539 having the plurality of semi- And a material having a refractive index value of the same magnitude as the refractive index value in the major axis direction of the liquid crystal molecule 541 having the orientation characteristic.

9A, different voltages are applied to the first and second electrodes 522 and 537 of the liquid crystal lens 510 so that a sufficient vertical electric field is generated between the first and second electrodes 522 and 537 The liquid crystal molecules 541 in the first liquid crystal layer 540 having a plurality of semicylindrical shapes are aligned in parallel with the vertical electric field by the vertical electric field between the first and second electrodes 522 and 537 .

On the other hand, the light emitted from the lower backlight unit passes through the first liquid crystal layer 540 having a state in which the liquid crystal molecules as described above are vertically arranged by the application of a vertical electric field, In this case, the light has a refractive index (referred to as n _e ) in the major axis direction of the liquid crystal molecules 541.

In this case, the insulating layer 539 having a plurality of semicylindrical concave portions has the same refractive index value as the refractive index of the liquid crystal molecules 541 forming the first liquid crystal layer 540 in the major axis direction, The first liquid crystal layer 540 passes through the first liquid crystal layer 540 and goes straight as the light advances without being refracted when the liquid crystal layer 540 is incident on the insulating layer 539. Accordingly, Lens).

9B, if no voltage is applied to the first and second electrodes 522 and 537, a vertical electric field is not generated between the first and second electrodes 522 and 537, The liquid crystal molecules 541 in the first liquid crystal layer 540 having a semicylindrical shape are brought into a state in which the major axis thereof is parallel to the first alignment layer 540. In this state, when the light emitted from the lower backlight unit is incident on the first liquid crystal layer 540, the light experiences a refractive index (referred to as n _o ) in the direction of the short axis of the liquid crystal molecules 541, The light having passed through the first liquid crystal layer 540 having the refractive index n _{o in} the minor axis direction has a refractive index equal to the refractive index n _{e in} the major axis direction of the liquid crystal molecules 541, The refractive index n _e of the liquid crystal molecules 541 in the long axis direction is smaller than the refractive index n _o of the short axis direction, The first liquid crystal layer 540 serves as a lenticular lens because the first liquid crystal layer 540 is refracted with a larger angle based on the normal at the point where the light is incident.

As a comparative example, when the refractive index of the insulating layer having the semicylindrical concave portion has a refractive index in the uniaxial direction of the liquid crystal molecules of the first liquid crystal layer, the liquid crystal molecules in the first liquid crystal layer, The first liquid crystal layer passes through the first liquid crystal layer from the bottom to the top of the first liquid crystal layer and is reflected by the first alignment layer. And passes through the insulating layer as it is. On the other hand, when a voltage is applied to the first and second electrodes in the same state, the long axes of the liquid crystal molecules are aligned perpendicular to the first and second alignment layers. In this case, The refractive index in the major axis direction is felt. In this state, if light passing through the first liquid crystal layer is incident on the insulating layer having a refractive index in the direction of the short axis of the liquid crystal, refraction occurs at the boundary due to the difference in refractive index. However, the liquid crystal having the horizontal orientation characteristic is characterized in that the refractive index in the short axis direction of the liquid crystal molecule has a larger value than the refractive index in the long axis direction. In the case where light is incident on a substance having a high refractive index from a substance having a low refractive index, With a refraction angle smaller than the incident angle. Therefore, in this case, the light having passed through the first liquid crystal layer is incident on the insulating layer, and the light has a shape spreading as if passing through the scattering layer. Even if it acts as a diffusion lens for diffusing light But the first liquid crystal layer does not function as a lenticular lens.

Therefore, in order for the first liquid crystal layer 540 to function as a semi-cylindrical lens or a lenticular lens, the insulating layer 539 having a plurality of semicylindrical concave portions is formed on the liquid crystal molecules 541 in the major axis direction (N _e ) of the same size as the refractive index n _e .

A description will be given of a case where a semi-cylindrical first liquid crystal layer is formed by using a liquid crystal having a property that its long axis is vertically aligned with respect to an alignment film as a modification of the fifth embodiment. In this case as well, the insulating layer having the recesses of the semi-cylindrical shape is configured to have a refractive index value equal in magnitude to the refractive index in the longitudinal direction of the vertically aligned liquid crystal.

In the liquid crystal lens according to the modified example of the fifth embodiment, when voltage is applied to the first and second electrodes, the liquid crystal molecules in the first liquid crystal layer are horizontally aligned with respect to the first and second alignment layers, The first liquid crystal layer functions as a semi-cylindrical lens (lenticular lens) because the refractive index difference between the liquid crystal layer and the insulating layer is greater than the refractive index of the insulating layer.

On the other hand, when no voltage is applied to the liquid crystal lens according to the modified example of the fifth embodiment, the liquid crystal molecules having the vertical alignment characteristic have the liquid crystal molecules in the semi-cylindrical first liquid crystal layer, In this case, the light passing through the first liquid crystal layer senses the refractive index in the major axis direction of the liquid crystal, which is equal to the refractive index of the insulating layer having the semi-cylindrical recess, The light is not refracted but travels straight ahead, and the semi-cylindrical first liquid crystal layer does not serve as a lens.

Therefore, the liquid crystal lens provided in the liquid crystal display according to the fifth embodiment and the modified embodiment also functions as a lens or simply acts as a transparent layer depending on whether a voltage is applied to the liquid crystal lens, It is also possible to view 3D or 2D images.

Hereinafter, the overall configuration of the liquid crystal display according to the fifth embodiment of the present invention constituting the liquid crystal lens having the above-described configuration with reference to FIG. 8 will be described.

The liquid crystal display device 501 according to the fifth embodiment of the present invention includes a liquid crystal lens 540 including a first liquid crystal layer 540 having a plurality of semi-cylindrical shapes and an insulating layer 539 having a plurality of semi- And a liquid crystal display panel 550 formed integrally with the liquid crystal lens 510 at a lower portion thereof.

The liquid crystal lens 510 having the plurality of semicylindrical first liquid crystal layers 540 has the same structure as described above. The liquid crystal display panel 550, which is disposed under the liquid crystal lens 510, And a second liquid crystal layer 580 formed between the third and fourth substrates 560 and 570. The third and fourth substrates 560 and 570 are spaced apart from each other. At the inner surface (upper surface) of the third substrate 560, pixel electrodes 562 are formed corresponding to the image pixels P1 and P2. And an electrode 572 is formed on the entire surface. Although not shown in the drawing, the initial arrangement of the liquid crystal molecules in the second liquid crystal layer 580 located between the two electrodes 562 and 572 is formed in the upper portion of the pixel electrode 562 and the lower portion of the common electrode 572, Third and fourth alignment layers (not shown) are further formed to keep the alignment layers uniform. At this time, the second liquid crystal layer 580 is formed between the pixel electrode 562 and the common electrode 572, more precisely between the third and fourth alignment films (not shown) 572 by varying the polarization state and transmittance of the incident light.

The first substrate 520 of the liquid crystal lens 510 and the fourth substrate 570 of the liquid crystal display panel 550 may be formed to have a predetermined width And the first and second polarizing plates 592 and 594 necessary for image display of the liquid crystal display panel 550 are disposed on the third substrate 560 as one substrate of the liquid crystal display panel 550, And the outer surface of the second substrate 530, which is one substrate of the liquid crystal lens 510, respectively. At this time, the polarization axes of the first and second polarizing plates 592 and 594 are configured to be orthogonal to each other.

The first polarizing plate 592 and the second polarizing plate 594 are respectively formed on the outer surfaces of the liquid crystal lens 510 and the substrates 530 and 560 located at the outermost sides of the liquid crystal display panel 510, The display quality deterioration due to the path diffusion of light which may occur when the polarizing plate 594 is positioned between the liquid crystal display panel 550 and the liquid crystal lens 510 is prevented.

10 is a view schematically showing a light path for one pixel region located at an outermost position of a display region in a liquid crystal display device in which a polarizing plate is placed between a liquid crystal display panel and a liquid crystal lens as another comparative example of the fifth embodiment . In this case, only the constituent elements which simplify the components and affect the light path are shown, and the same reference numerals are given to the fifth embodiment.

The polarizing plates 592 and 594 themselves have a characteristic of diffusing light transmitted through the polarizing plates 592 and 594 themselves (in particular, for realizing a wide viewing angle), and the polarizing plates 592 and 594 having such characteristics are disposed on the third And the fourth substrate 560 and 570, light having a specific path from the light incident on the liquid crystal lens 510 by the light diffusion function of the polarizers 592 and 594 The light incident on the outermost side of the first liquid crystal layer 540 having the shape of the first liquid crystal layer 540 and the light of the first path of the first liquid crystal layer 540 are normal to the front side of the liquid crystal lens 510 viewed from the front side of the liquid crystal lens 510 The light of the path (the second path) that travels to the side of the liquid crystal display device 501 after passing through the liquid crystal lens 510 due to the diffusion phenomenon of the second polarizing plate 594, .

The first and second polarizing plates 592 and 594 and the first and second polarizing plates 592 and 594 are disposed on the opposite sides of the liquid crystal display panel 550 and the liquid crystal lens 510 to prevent light leakage caused by the polarizing plate 594 being positioned between the liquid crystal display panel 550 and the liquid crystal lens 510, More specifically, the second polarizing plate 594 is formed on the outer surface of the second substrate 530 constituting the liquid crystal lens 510.

Although not shown in the drawing, the liquid crystal display panel 550 includes a gate line and a data line crossing each other between the third substrate 560 and the pixel electrode 562, and a thin film transistor connected to the gate line and the data line are formed And the thin film transistor may be connected to the pixel electrode 562 to switch a voltage applied to the pixel electrode 562. Between the first substrate 520 and the common electrode 572, a black matrix corresponding to the gate wiring and the data wiring, and a color filter layer under the black matrix can be formed.

<Sixth Embodiment>

 11 is a cross-sectional view of a liquid crystal display device including a liquid crystal lens according to a sixth embodiment of the present invention.

The liquid crystal display device 601 according to the sixth embodiment of the present invention also includes a first liquid crystal layer 640 having a plurality of semicylindrical shapes in the same manner as the liquid crystal lens configured in the liquid crystal display device according to the fifth embodiment, And a liquid crystal lens 610 and an LCD panel 650 including an insulating layer 639 having a structure having a semi-cylindrical recess to capture the first liquid crystal layer. The point is that a total of three substrates are used. The other constituent elements have the same configuration as that of the above-described fifth embodiment, and the same constituent elements are given the reference numerals added to the fifth embodiment by adding 100 to them.

8) of the first and second substrates (520 and 530 in Fig. 8) provided in the liquid crystal lens (510 in Fig. 8) shown in the fifth embodiment, respectively, in the sixth embodiment of the present invention, 520) is replaced with a fourth substrate (570 in Fig. 8) constituting the upper substrate of the liquid crystal display panel (550 in Fig. 8).

That is, in the sixth embodiment of the present invention, the fourth substrate 670 is a substrate constituting the liquid crystal display panel 650 and a substrate constituting the liquid crystal lens 610 disposed thereon .

In this case, after the liquid crystal display panel 650 and the liquid crystal lens 610 are manufactured and attached, the liquid crystal display panel 650 is first manufactured using the third and fourth substrates 660 and 670, A first alignment layer 622 is formed on the outer surface of the fourth substrate 670 constituting the upper substrate of the display panel 650 and a plurality of the alignment layers 622 are formed on the second substrate 630, And then forming a first liquid crystal layer 640 having a semicylindrical shape in the plurality of recesses by injecting or dropping liquid crystals to form an insulating layer 639 having a semicylindrical concave portion of the semi- . Here, the ends of each of the plurality of recesses are brought into contact with the first alignment film 622 (E).

In this case, the liquid crystal display device 601 including the liquid crystal lens 610 is formed of three substrates (second, third, and fourth substrates 630, 660, and 670) .

Other components are the same as those of the fifth embodiment described above, and a description thereof will be omitted.

On the other hand, in the liquid crystal display device according to the second to sixth embodiments described above, in the case of the liquid crystal display panel as the constituent element, the pixel electrode and the common electrode face each other with the liquid crystal layer interposed therebetween, The liquid crystal display panel is not limited to this configuration and may be variously changed according to the driving mode of the liquid crystal display panel. For example, when driven by a transverse electric field system, common electrodes may be formed on the same substrate on which the pixel electrodes are formed, alternating with the pixel electrodes.

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

1A and 1B are a perspective view and a cross-sectional view of a typical liquid crystal lens, respectively.

FIG. 2 is a graph showing a phase change of an incident light when light passes through the liquid crystal lens of FIGS. 1A and 1B. FIG.

3 is a cross-sectional view schematically showing a liquid crystal lens according to a first embodiment of the present invention.

4 is a sectional view of a liquid crystal display device including a liquid crystal lens according to a second embodiment of the present invention.

5 is a sectional view of a liquid crystal display device including a liquid crystal lens according to a third embodiment of the present invention.

6 is a sectional view of a liquid crystal display device including a liquid crystal lens according to a fourth embodiment of the present invention.

7A and 7B are schematic views showing an optical path and a polarization state of incident light of a liquid crystal display device including a liquid crystal lens according to a fourth embodiment of the present invention;

8 is a cross-sectional view of a liquid crystal display device including a liquid crystal lens according to a fifth embodiment of the present invention.

9A and 9B are diagrams showing changes in the first liquid crystal layer when the power is turned on / off with respect to the operation of the liquid crystal lens 510 according to the fifth embodiment.

10 is a view schematically showing a light path for one pixel region located at an outermost position of a display region in a liquid crystal display device which is positioned between a liquid crystal display panel and a liquid crystal lens as another comparative example of the fifth embodiment,

 11 is a sectional view of a liquid crystal display device including a liquid crystal lens according to a sixth embodiment of the present invention.

Description of the Related Art

410: liquid crystal lens 420: first substrate

422: first electrode 424: first alignment film

430: second substrate 432: second electrode

434: insulating layer 436: third electrode

438: second orientation film 440: first liquid crystal layer

450: liquid crystal display panel 460: third substrate

480: second liquid crystal layer 462: pixel electrode

472: common electrode 492: first polarizer plate

494: Second polarizer plate

Claims (20)

A first substrate; A second substrate facing the first substrate and spaced apart from the first substrate; A first electrode formed on the inner surface of the first substrate; A plurality of second electrodes repeatedly formed on the inner surface of the second substrate, each of the second electrodes having a first opening each having a width corresponding to the first distance; A first liquid crystal layer formed between the first electrode and the plurality of second electrodes; A plurality of third electrodes repeatedly formed between the second electrode and the first liquid crystal layer, each having a second opening each having a width corresponding to the second distance; A third substrate disposed under the first substrate; A fourth substrate spaced apart from and facing the third substrate and in contact with the first substrate; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the third substrate and the fourth substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate, And the liquid crystal display device. A first substrate; Second and third substrates facing each other with the first substrate interposed therebetween; A first electrode formed on one surface of the first substrate facing the second substrate; A plurality of second electrodes repeatedly formed on the inner surface of the second substrate, each of the second electrodes having a first opening each having a width corresponding to the first distance; A first liquid crystal layer formed between the first electrode and the plurality of second electrodes; A plurality of third electrodes repeatedly formed between the second electrode and the first liquid crystal layer, each having a second opening each having a width corresponding to the second distance; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the first substrate and the third substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate, And the liquid crystal display device. delete 3. The method according to claim 1 or 2, Wherein the plurality of second electrodes and the plurality of third electrodes are bar-shaped. 3. The method according to claim 1 or 2, Wherein the plurality of second electrodes and the plurality of third electrodes are integrally formed. 3. The method according to claim 1 or 2, Dimensional stereoscopic image when voltage is applied to the first electrode, the plurality of second electrodes, and the plurality of third electrodes, and displays the three-dimensional image on the first electrode, the plurality of second electrodes, Dimensional plane image when no voltage is applied to the liquid crystal display panel. The method according to claim 6, Wherein the pixel electrodes are formed on the inner surface of the third substrate to be spaced apart from each other to define a plurality of image pixels, and when the liquid crystal display device displays the three-dimensional image, A liquid crystal display device for displaying two images alternately. The method according to claim 6, Wherein when the liquid crystal display displays the three-dimensional stereoscopic image, the first liquid crystal layer changes the optical path for the selected one polarized light and does not change the optical path for the other polarized light. 3. The method according to claim 1 or 2, A first alignment layer formed between the first electrode and the first liquid crystal layer; A second alignment layer formed between the third electrode and the first liquid crystal layer; An insulating film formed between the second electrode and the third electrode, The liquid crystal display device further comprising: 3. The method according to claim 1 or 2, A first voltage, a second voltage and a third voltage are applied to the first electrode, the plurality of second electrodes and the plurality of third electrodes, respectively, and at least one of the first to third voltages is an AC voltage, Display device. 11. The method of claim 10, Wherein the first voltage is a DC voltage and the second and third voltages are AC voltages having different magnitudes from the same frequency. 3. The method according to claim 1 or 2, Wherein the first distance is smaller than the second distance. A first substrate; A second substrate facing the first substrate and spaced apart from the first substrate; A first electrode formed on the inner surface of the first substrate; A first alignment layer in the form of a plate formed on the first electrode; A second electrode formed on the inner surface of the second substrate; An insulating layer formed on the lower portion of the second electrode, the insulating layer having a plurality of semi-cylindrical concave depressions; A second alignment layer formed along the interior of each of the plurality of recesses under the insulating layer; A first liquid crystal layer formed between the first alignment layer and the second alignment layer to fill the plurality of recesses; A third substrate disposed under the first substrate; A fourth substrate spaced apart from and facing the third substrate and in contact with the first substrate; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the third substrate and the fourth substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate, Wherein the plurality of recesses are connected to each other and the respective ends thereof are in contact with the first alignment layer. A first substrate; A second substrate spaced apart from and facing the first substrate above the first substrate; A first electrode in the form of a plate formed on an upper surface of the first substrate; A first alignment layer in the form of a plate formed on the first electrode; A second electrode in the form of a plate formed on a lower surface of the second substrate; An insulating layer formed on the lower portion of the second electrode, the insulating layer having a plurality of semi-cylindrical concave depressions; A second alignment layer formed along the interior of each of the plurality of recesses under the insulating layer; A first liquid crystal layer formed between the first alignment layer and the second alignment layer to fill the plurality of recesses; A third substrate spaced apart from and facing the first substrate and contacting the first substrate; A pixel electrode formed on the inner surface of the third substrate; A second liquid crystal layer formed between the first substrate and the third substrate; A first polarizer formed on an outer surface of the third substrate; And a second polarizer formed on an outer surface of the second substrate, Wherein the plurality of recesses are connected to each other and the respective ends thereof are in contact with the first alignment layer. The method according to claim 13 or 14, Wherein the insulating layer has a refractive index equal to a long axis refractive index of the liquid crystal molecules constituting the first liquid crystal layer. The method according to claim 13 or 14, Wherein the liquid crystal constituting the first liquid crystal layer has a vertical alignment or a horizontal alignment characteristic. delete The method according to claim 13 or 14, Wherein the first electrode and the second electrode are formed in a plate shape on the first substrate and the second substrate, respectively. The method according to claim 1 or 13, A common electrode is further formed on the inner surface of the fourth substrate, and the second liquid crystal layer is formed between the pixel electrode and the common electrode. The method according to claim 2 or 14, A common electrode is further formed on one surface of the first substrate facing the third substrate, and the second liquid crystal layer is formed between the pixel electrode and the common electrode.

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