Wire grid polarizer, liquid crystal display having the same and method of manufacturing the same

A wire grid polarizer includes a substrate, a first layer and a second layer disposed on the first layer, in which a first region and a second region are defined in the first layer, the first layer includes: a first wire grid including a plurality of first wires and disposed in the first region, where the first wires are spaced apart from each other, and no wire grid is disposed in the second region; and a first protection layer which covers the first wire grid, a third region and a fourth region are defined in the second layer, and the second layer includes a second wire grid including a plurality of second wires and disposed in the third region, where the second wires are spaced apart from each other, and no wire grid is disposed in the fourth region.

RELATED APPLICATIONS

This application claims priority to Korean Patent Application No. 10-2014-0054433, filed on May 7, 2014, and all the benefits accruing therefrom under 35 U.S.C. §119, the content of which in its entirety is herein incorporated by reference.

BACKGROUND

The disclosure relates to a wire grid polarizer having a large area, a liquid crystal display including the wire grid polarizer, and a method of manufacturing the wire grid polarizer.

2. Description of the Related Art

Light emitted from a light source may be controlled using polarization characteristics thereof. For example, in a liquid crystal display including a liquid crystal panel, the liquid crystal panel functions as a shutter for blocking or transmitting light by varying the polarization direction of linearly polarized light passing therethrough using liquid crystals. A liquid crystal display may include first and second polarizing plates having polarization directions that are perpendicular to each other, a liquid crystal layer between the first and second polarizing plates, and a thin film transistor (“TFT”) in each pixel. A voltage is selectively applied to each pixel according to the switching operation of the TFT. In such a liquid crystal display, when a voltage is applied to a pixel, liquid crystal molecules may be aligned in a line such that incident light may pass through the liquid crystal layer without a change in the polarization direction thereof, and the light is blocked by the second polarizing plate. In such a liquid crystal display, when the voltage is not applied to the pixel, the liquid crystal molecules may be arranged in a twisted manner such that incident light passes through the liquid crystal layer while the polarization direction thereof is changed according to the arrangement of the liquid crystal molecules, and the light passes through the second polarizing plate. Accordingly, when liquid crystal is in a twisted state, a pixel may be shown as white, and when liquid crystal is not in a twisted state, the pixel may be shown as black. However, since the optical efficiency of a polarizing plate is typically low, a liquid crystal display using a polarizing plate may have a low optical efficiency.

Furthermore, a large liquid crystal display may include a large-sized polarizing plate.

SUMMARY

Provided are embodiments of a wire grid polarizer that may be effectively and efficiently manufactured to have a large size.

Provided are embodiments of a liquid crystal display including a wire grid polarizer that may be effectively and efficiently manufactured to have a large size.

Provided are embodiments of a method of manufacturing a large-size wire grid polarizer.

According to an embodiment of the invention, a liquid crystal display includes: a light source unit; a first substrate disposed on the light source unit; an electrode layer disposed on the first substrate; a second substrate separate from the electrode layer; a polarizing plate disposed on the second substrate; a liquid crystal layer disposed between the electrode layer and the second substrate; and a wire grid polarizer disposed between the light source and the first substrate, where the wire grid polarizer includes: a first layer, in which a first region and a second region are defined, where a first wire grid including a plurality of first wires is disposed in the first region, the first wires are spaced apart from each other, and no wire grid is disposed in the second region; and a second layer disposed on the first layer and in which a third region and a fourth region are defined, where a second wire grid including a plurality of second wires is disposed in the third region, the second wires are spaced apart from each other, and no wire grid is disposed in the fourth region.

In an embodiment, the first region and the third region may not overlap each other, and the second region and the fourth region may not overlap each other.

In an embodiment, the first to fourth regions may be arranged in such a manner that the first wires and the second wires may be arranged at regular intervals when viewed from a top plan view.

In an embodiment, the fourth region may be disposed to correspond to the first region and the third region may be disposed to correspond to the second region such that the first wires and the second wires may be arranged at regular intervals when viewed from a top plan view.

In an embodiment, each of the first wires and the second wires may include a metal.

In an embodiment, the metal of each of the first wires and the second wires may include aluminum (Al), silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt) or a combination thereof.

In an embodiment, the second layer may further include a second protection layer which covers the third region and the fourth region.

In an embodiment, the liquid crystal display may further include a third layer disposed on the second protection layer, where a fifth region and a six region are defined in the third layer, a third wire grid including a plurality of third wires is disposed in the fifth region, the third wires are spaced apart from each other, and no wire grid is disposed in the sixth region.

In an embodiment, the first region, the third region and the fifth region may not overlap each other, and the second region, the fourth region and the sixth region may not overlap each other.

In an embodiment, the first region, the third region and the fifth region may partially overlap each other, and the second region, the fourth region and the sixth region may partially overlap each other, where only two of the first wires, the second wires and the third wires may be arranged to overlap each other across the first layer, the second layer and the third layer.

According to another embodiment of the invention, a wire grid polarizer includes: a substrate; a first layer disposed on the substrate, where a first region and a second region are defined in the first layer, and the first layer includes a first wire grid including a plurality of first wires and disposed in the first region, where the first wires are spaced apart from each other, and no wire grid is disposed in the second region, and a first protection layer which covers the first and second regions; and a second layer disposed on the first layer, where a third region and a fourth region are defined in the second layer, and the second layer includes a second wire grid including a plurality of second wires and disposed in the third region, where the second wires are spaced apart from each other, and no wire grid is disposed in the fourth region.

In an embodiment, the first region and the third region may not overlap each other, and the second region and the fourth region may not overlap each other.

In an embodiment, a plurality of first wire grids and a plurality of second wire grids are disposed along the first layer and the second layer, respectively.

In an embodiment, the fourth region may be disposed to correspond to the first region and the third region may be disposed to correspond to the second region such that the first wires and the second wires may be arranged at regular intervals when viewed from a top plan view.

In an embodiment, each of the first wires and the second wires may include a metal.

In an embodiment, the metal of each of the first wires and the second wires may include aluminum (Al), silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt) or a combination thereof.

In an embodiment, the second layer may further include a second protection layer covering the third region and the fourth region.

In an embodiment, the wire grid polarizer may further include a third layer disposed on the second protection layer, where a fifth region and a six region are defined in the third layer, a third wire grid including a plurality of third wires is disposed in the fifth region, the third wires are spaced apart from each other, and no wire grid is disposed in the sixth region.

In an embodiment, the first region, the third region and the fifth region may not overlap each other, and the second region, the fourth region and the sixth region may not overlap each other.

In an embodiment, The first region, the third region and the fifth region may partially overlap each other, and the second region, the fourth region and the sixth region may partially overlap each other, where only two of the first wires, the second wires and the third wires may be arranged to over overlap each other across the first layer, the second layer and the third layer.

According to another embodiment of the invention, a method of manufacturing a wire grid polarizer includes: providing a first layer on a substrate; providing a first mask on the first layer; providing a first region, in which a first wire grid is provided, and a second region, in which no wire grid is provided, by patterning and etching the first layer based on a pattern of the first mask; providing the first wire grid in the first region through a nanoimprinting process; providing a first protection layer on the first region and the second region; providing a second layer on the first protection layer; providing a second mask on the second layer; providing a third region, in which a second wire grid is provided, and a fourth region, in which no wire grid is provided, by patterning and etching the second layer based on a pattern of the second mask; and providing the second wire grid in the third region through a nanoimprinting process.

According to another embodiment of the invention, a method of manufacturing a wire grid polarizer includes: providing a first layer on a substrate; providing a first mask on the first layer; defining a first region and a second region on the substrate by etching the first layer based on a pattern of the first mask; providing the first wire grid on the first region through a nanoimprinting process; providing a first protection layer on the first region and the second region; providing a second mask pattern on the second layer; etching a region of the first protection layer corresponding to the second region using the second mask; providing a second layer on the second region; and providing a second wire grid on the second region through a nanoimprinting process.

DETAILED DESCRIPTION

Hereinafter, embodiments of a wire grid polarizer, a liquid crystal display including the wire grid polarizer, and a method of manufacturing the wire grid polarizer will be described in detail with reference to the accompanying drawings.

FIG. 1is a perspective view of an embodiment of a wire grid polarizer1according to the invention, andFIGS. 2 and 3are a front view and a plan view of the wire grid polarizer1ofFIG. 1, respectively.

Referring toFIGS. 1 to 3, an embodiment of the wire grid polarizer1may include a substrate10, a first layer20on the substrate10, and a second layer30on the first layer20. The substrate10may be a transparent substrate that transmits light. In one embodiment, for example, the substrate10may be a glass substrate or a transparent plastic substrate.

The first layer20may include first wire grids25. The first layer20may include first regions20A in which the first wire grids25are disposed and second regions20B in which no wire grid is disposed. The second regions20B may be defined as a portion between neighboring first wire grids25. Each of the first wire grids25may include a plurality of first wires25athat are separate, e.g., spaced apart, from each other. In one embodiment, for example, in each of the first wire grids25, the first wires25amay be arranged substantially parallel to each other at regular intervals, e.g., constant intervals. First grooves25bmay be formed or defined between the first wires25a. The pitch of the first wires25amay be less than a predetermined wavelength of light, e.g., the wavelength of light to be used. In one embodiment, for example, the pitch between the first wires25amay be about ¼ or less times the predetermined wavelength of light. In one embodiment, for example, the pitch between the first wires25amay be greater than about zero (0) nanometer (nm) and equal to or less than about 200 nm. In one embodiment, for example, the first wires25amay have a fill factor that is equal to or greater than about 0.3 and less than about 1. The fill factor refers to a sectional area ratio of the first wires25aand the first grooves25b. The height of the first wires25amay be about 100 nm or greater, for example, and the aspect ratio of the first wires25amay be about 1 or greater, for example.

The first wires25amay include a metal. In one embodiment, for example, the first wires25amay include aluminum (Al), silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt) or a combination thereof.

In such an embodiment, the second regions20B do not include a wire grid. The second regions20B may buffer the effects of errors that may occur in neighboring regions when the first wires25aare formed. In an embodiment, the second regions20B may be arranged to allow the first regions20A to meet each other in small areas, to thereby reduce errors.

The first regions20A and the second regions20B may be alternately arranged with each other in the first layer20. The first regions20A and the second regions20B may be arranged in various manners. The first regions20A and the second regions20B may be arranged in a predetermined arrangement, e.g., a first arrangement. In one embodiment, for example, as shown inFIG. 1, the first regions20A and the second regions20B are arranged in the form of a go board, but the arrangement of the first regions20A and the second regions20B are not limited thereto. In an alternative embodiment, the first regions20A and the second regions20B may be arranged in another manner. In an embodiment, where the first regions20A and the second regions20B are arranged in the form of a go board, neighboring first regions20A may meet each other only at corners thereof, and thus areas in which the first regions20A meet each other may be effectively minimized.

The first layer20may further include a first protection layer27. The first protection layer27may include or be formed of a transparent material. The first protection layer27may cover the first regions20A and the second regions20B. In one embodiment, for example, the first wire grids25may be disposed in the first protection layer27. However, the first protection layer27is not limited thereto. In one embodiment, for example, the first protection layer27may be disposed on the first wire grids25.

The second layer30may include second wire grids35. The second layer30includes third regions30A in which the second wire grids35are disposed, and fourth regions30B in which no wire grid is disposed. Each of the second wire grids35may include a plurality of second wires35athat are separate from each other. In one embodiment, for example, in each of the second wire grids35, the second wires35amay be arranged substantially parallel to each other at regular intervals. Second grooves35bmay be defined or formed between the second wires35a. The pitch of the second wires35amay be less than the predetermined wavelength of light. In one embodiment, for example, the pitch between the second wires35amay be about ¼ or less times the predetermined wavelength of light. In one embodiment, for example, the pitch between the second wires35amay be greater than about zero (0) nm and equal to or less than about 200 nm. In one embodiment, for example, the second wires35amay have a fill factor that is equal to or greater than about 0.3 and less than about 1. The second wires35amay have an aspect ratio equal to or greater than about 1. The second wire grids35may be substantially the same as the first wire grids25.

The second wires35amay include a metal. In one embodiment, for example, the second wires35amay aluminum (Al), silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt) or a combination thereof.

The fourth regions30B do not include a wire grid. The fourth regions30B may buffer the effects of errors that may occur in neighboring regions when the second wires35aof the third regions30A are formed.

The third regions30A and the fourth regions30B may be alternately arranged with each other in the second layer30. The third regions30A and the fourth regions30B may be arranged in various manners. The third regions30A and the fourth regions30B may be arranged in a predetermined arrangement, e.g., a second arrangement. In one embodiment, for example, as shown inFIG. 1, the third regions30A and the fourth regions30B are arranged in the form of a go board. However, the third regions30A and the fourth regions30B are not limited thereto. In an alternative embodiment, the third regions30A and the fourth regions30B may be arranged in another manner or form.

The first regions20A, the second regions20B, the third regions30A and the fourth regions30B may be arranged in relation to each other. As shown inFIG. 3, the first regions20A, the second regions20B, the third regions30A and the fourth regions30B may be arranged to allow the first wires25aand the second wires35ato be alternately arranged with each other at regular intervals when viewed from a top plan view. In such an embodiment, when viewed from a top plan view, as a whole, the first wires25aand the second wires35amay be arranged at regular intervals corresponding to pitches between the first wires25aor the second wires35a, and thereby define a single grid.

In one embodiment, for example, the first regions20A, the second regions20B, the third regions30A and the fourth regions30B may be arranged in such a manner that the first regions20A do not overlap the third regions30A and the second regions20B do not overlap the fourth regions30B. In an embodiment, the fourth regions30B may be disposed to correspond to, e.g., on top of, the first regions20A, and the third regions30A may be disposed to correspond to the second regions20B. In such an embodiment, the first regions20A may overlap the fourth regions30B, and the second regions20B may overlap the third regions30A. Therefore, when the first layer20and the second layer30of the wire grid polarizer1are viewed from a top plan view as a whole, an optical effect substantially the same as that of the first wire grids25and the second wire grids35arranged in a single layer may be obtained.

When the pitch of wires is less than the wavelength of incident light, light polarized substantially parallel to the wires may be reflected and light polarized perpendicular to the wires may pass through the wires. Accordingly, based on such an optical property, the wire grid polarizer1may transmit only first polarized light and may reflect second polarized light. The first polarized light may be p-polarized light, and the second polarized light may be s-polarized light. The width, thickness and pitch of the first and second wires25aand35amay determine the transmissivity and reflectivity of the wire grid polarizer1.

In such an embodiment, where the wire grid polarizer1transmits first polarized light and reflects second polarized light for reusing the second polarized light, the optical efficiency of the wire grid polarizer1may be high.

FIG. 4is a view of an embodiment of the wire grid polarizer further including a second protection layer. Referring toFIG. 4, in an embodiment, the second layer30may further include a second protection layer37for protecting the second wire grids35. The second protection layer37may include or be formed of a transparent material. The second protection layer37may cover the third regions30A and the fourth regions30B. In one embodiment, for example, the second protection layer37may be disposed in the second wire grids35. However, the second protection layer37is not limited thereto. In one embodiment, for example, the second protection layer37may be disposed on the second wire grids35.

FIG. 5illustrates the arrangement of the first regions20A, the second regions20B, the third regions30A and the fourth regions30B in an alternative embodiment of the wire grid polarizer. Referring toFIG. 5, the first regions20A and the second regions20B may have a diamond shape and may be alternately arranged with each other, and the third regions30A and the fourth regions30B may have a diamond shape and may be alternately arranged with each other.FIG. 6illustrates the arrangement of the first regions20A, the second regions20B, the third regions30A and the fourth regions30B in another alternative embodiment of the wire grid polarizer. Referring toFIG. 6, the first regions20A and the second regions20B may have a triangular shape and may be alternately arranged with each other, and the third regions30A and the fourth regions30B may have a triangular shape and may be alternately arranged with each other. The first regions20A and the third regions30A do not overlap each other, and the second regions20B and the fourth regions30B do not overlap each other. In such an embodiment, the first regions20A, the second regions20B, the third regions30A and the fourth regions30B may be arranged in various manners to allow the first wires25aand the second wires35ato be arranged at regular intervals when the first regions20A, the second regions20B, the third regions30A and the fourth regions30B are viewed from a top plan view.

FIG. 7illustrates another embodiment of a wire grid polarizer100according to the invention.

The wire grid polarizer100may include a substrate110, a first layer120on the substrate110, a second layer130on the first layer120, and a third layer140on the second layer130. The substrate110may be a transparent substrate that transmits light. In one embodiment, for example, the substrate110may be a glass substrate or a transparent plastic substrate.

The first layer120may include first regions120A including first wire grids125and second regions120B not including a wire grid. Each of the first wire grids125may include a plurality of first wires125athat are separate from each other. First grooves125bmay be defined or formed between the first wires125a.

The second regions120B do not include a wire grid, and the first regions120A and the second regions120B may be alternately arranged with each other. The first regions120A and the second regions120B may be arranged in various manners. The first regions120A and the second regions120B may be arranged in a predetermined arrangement, e.g., a first arrangement. In one embodiment, for example, as shown inFIG. 7, the second regions120B may be larger than the first regions120A.

The first layer120may further include a first protection layer127. The first protection layer127may include or be formed of a transparent material. The second layer130may include third regions130A including wire grids135and fourth regions130B not including a wire grid. Each of the second wire grids135may include a plurality of second wires135athat are separate from each other. Second grooves135bmay be defined or formed between the second wires135a.

The fourth regions130B do not include a wire grid, and the third regions130A and the fourth regions130B may be alternately arranged with each other. The third regions130A and the fourth regions130B may be arranged in various manners. The third regions130A and the fourth regions130B may be arranged in a predetermined arrangement, e.g., a second arrangement. The third regions130A may be smaller than the fourth regions130B.

The second layer130may further include a second protection layer137. The second protection layer137may include or be formed of a transparent material. The third layer140may include fifth regions140A in which third wire grids145are disposed, and sixth regions140B in which no wire grid is disposed. Each of the third wire grids145may include a plurality of third wires145athat are separate from each other. Third grooves145bmay be defined or formed between the third wires145a.

The sixth regions140B do not include a wire grid, and the fifth regions140A and the sixth regions140B may be alternately arranged with each other. The fifth regions140A and the sixth regions140B may be arranged in various manners. The fifth regions140A and the sixth regions140B may be arranged in a predetermined arrangement, e.g., a third arrangement. The fifth regions140A may be smaller than the sixth regions140B.

In an embodiment shown inFIG. 7, the first wire grids125, the second wire grids135and the third wire grids145have substantially the same structures and functions as those of the first wire grids25and the second wire grids35of an embodiment described above with reference toFIGS. 1 to 3, and any repetitive detailed descriptions thereof will be omitted.

The first regions120A, the second regions120B, the third regions130A, the fourth regions130B, the fifth regions140A and the sixth regions140B may be arranged in relation to each other. In an embodiment, when the first regions120A, the second regions120B, the third regions130A, the fourth regions130B, the fifth regions140A and the sixth regions140B are viewed from a plan view, the first wires125a, the second wires135aand the third wires145amay be arranged at regular intervals. In such an embodiment, when the wire grid polarizer100is viewed from a plan view, as a whole, the first wires125a, the second wires135aand the third wires145amay be arranged at regular intervals and may be shown as wire grids in a single layer.

In one embodiment, for example, the first regions120A, the third regions130A and the fifth regions140A may not overlap each other when viewed from a plan view such that the first wires125a, the second wires135aand the third wires145amay be arranged at regular intervals with each other. The second regions120B and the fourth regions130B may partially overlap each other, and the fourth regions130B and the sixth regions140B may partially overlap each other. Therefore, when the first layer120, the second layer130and the third layer140of the wire grid polarizer1are viewed as a whole, an optical effect substantially the same as an optical effect by wires arranged in a single layer may be obtained. The third layer140may further include a third protection layer147.

The number of layers of the wire grid polarizer100, regions of the layers including wire grids, and regions of the layers not including a wire grid may be variously adjusted as long as wires of the wire grid polarizer100are arranged at regular intervals when the wire grid polarizer100is viewed on a plan view.

FIG. 8illustrates another embodiment of a wire grid polarizer200according to the invention. The wire grid polarizer200may include a substrate210, a first layer220on the substrate210, a second layer230on the first layer220and a third layer240on the second layer230. The substrate210may be a transparent substrate that transmits light. In one embodiment, for example, the substrate210may be a glass substrate or a transparent plastic substrate.

The first layer220may include first regions220A, in which first wire grids225are disposed, and second regions220B in which no wire grid is disposed. Each of the first wire grids225may include a plurality of first wires225athat are separate from each other. First grooves125bmay be defined or formed between the first wires225a.

The second regions220B do not include a wire grid, and the first regions220A and the second regions220B may be alternately arranged with each other. The first regions220A and the second regions220B may be arranged in various manners. The first regions220A and the second regions220B may be arranged in a predetermined arrangement, e.g., a first arrangement. In one embodiment, for example, the first regions220A may be larger than the second regions220B.

The first layer220may further include a first protection layer227. The first protection layer227may include or be formed of a transparent material. The second layer230may include third regions230A, in which second wire grids235are disposed, and fourth regions230B in which no wire grid is disposed. Each of the second wire grids235may include a plurality of second wires235athat are separate from each other. Second grooves235bmay be defined or formed between the second wires235a.

The fourth regions230B do not include a wire grid, and the third regions230A and the fourth regions230B may be alternately arranged with each other. The third regions230A and the fourth regions230B may be arranged in various manners. The third regions230A and the fourth regions230B may be arranged in a predetermined arrangement, e.g., a second arrangement. The third regions230A may be larger than the fourth regions230B.

The second layer230may further include a second protection layer237. The second protection layer237may be formed of a transparent material. The third layer240may include fifth regions240A including third wire grids245and sixth regions240B not including a wire grid. Each of the third wire grids245may include a plurality of third wires245athat are separate from each other. Third grooves245bmay be formed between the third wires245a.

The sixth regions240B do not include a wire grid, and the fifth regions240A and the sixth regions240B may be alternately arranged. The fifth regions240A and the sixth regions240B may be arranged in various manners. The fifth regions240A and the sixth regions240B may be arranged in a predetermined arrangement, e.g., a third arrangement. The fifth regions240A may be larger than the sixth regions240B.

The first wire grids225, the second wire grids235, and the third wire grids245have substantially the same structures and functions as those of the first wire grids25and the second wire grids35described with reference toFIGS. 1 to 3, and thus detailed descriptions thereof will not be repeated.

The first regions220A, the second regions220B, the third regions230A, the fourth regions230B, the fifth regions240A and the sixth regions240B may be arranged in relation to each other. The first regions220A, the second regions220B, the third regions230A, the fourth regions230B, the fifth regions240A and the sixth regions240B may be arranged in such a manner that two of the first wires225a, the second wires235aand the third wires245aare arranged to overlap each other across the first layer220, the second layer230and the third layer240, that is, in a thickness direction of the first layer220, the second layer230and the third layer240. In one embodiment, for example, as a whole, the first wires225a, the second wires235aand the third wires245aare arranged in two layers. In such an embodiment, when the wire grid polarizer200is viewed as a whole, the wire grid polarizer200may have two wire grid layers.

In such an embodiment, when the first layer220, the second layer230and the third layer240of the wire grid polarizer1are viewed as a whole, an optical effect may be substantially the same as an optical effect by wires uniformly arranged in two layers may be obtained. The light transmitting efficiency of a wire grid polarizer may vary depending on the depth, thickness and pitch of wires. In one embodiment, for example, the wires may have an aspect ratio of about 1 or greater. When the depth of wires is larger than the width of the wires, a high light transmitting efficiency may be obtained. However, if the size of wires is less than the wavelength of incident light, it is difficult to form the wires to have a large depth. In an embodiment, wire grids may be stacked in a plurality of layers as shown inFIG. 8, such that the effect of increasing the depth of wires may be obtained.

The third layer240may further include a third protection layer247.

FIG. 9illustrates an alternative embodiment where the first regions220A, the second regions220B, the third regions230A, the fourth regions230B, the fifth regions240A and the sixth regions240B illustrated inFIG. 8arranged in a different manner. As shown inFIG. 9, the number of layers, regions of the layers including wire grids, and regions of the layers not including a wire grid may be variously adjusted to allow wires to be arranged at regular intervals in at least one layer when the wire grid polarizer200is viewed as a whole in cross-section.

FIG. 10is schematic view of an embodiment of a liquid crystal display250according to the invention. The liquid crystal display250may include a light source unit265and a wire grid polarizer WGP. The wire grid polarizer WGP may reflect a portion of light emitted from the light source unit265and may transmit a non-reflected portion of the light.

A first substrate270is disposed on the wire grid polarizer WGP, and an electrode layer275is disposed on the substrate. The electrode layer275and a second substrate285that are separate from each other are on the wire grid polarizer WGP. A liquid crystal layer280may be disposed between the electrode layer275and the second substrate285. A polarizing plate290may be disposed above, e.g., on a side of, the second substrate285.

In an embodiment, a reflection plate260may be disposed under the light source unit265.

The light source unit265may be a direct light-type or edge light-type light source unit. The direct light-type light source unit may be disposed under an in-cell polarizer (“IP”) to emit light directly to a liquid crystal display, and the edge light-type light source unit may emit light to a wire grid polarizer through a light guide plate (not shown). The direct light-type light source unit or the edge light-type light source unit may be applied to the liquid crystal display250in an embodiment of the invention. The light source unit265may include a light source such as a light-emitting diode (“LED”), an organic light-emitting diode (“OLED”), and a cold cathode fluorescent light (“CCFL”), for example. However, the light source unit265is not limited thereto.

The wire grid polarizer WGP may be an embodiment of the wire grid polarizers1,100or200described above with reference toFIGS. 1 to 9. The wire grid polarizer WGP may be manufactured to have a large size to be provided in a large liquid crystal display.

Next, an embodiment of a method of manufacturing a wire grid polarizer according to the invention will be described with reference toFIGS. 11 to 22.

Referring toFIG. 11, in an embodiment, a first layer320is disposed on a substrate310, and a first mask M1is disposed on the first layer320. The substrate310may be a transparent substrate that transmits light. In one embodiment, for example, the substrate310may be a glass substrate or a transparent plastic substrate.

Referring toFIG. 12, the first layer320may be patterned and etched based on a pattern of the first mask M1having a pattern corresponding to first regions320A and second regions320B. In such an embodiment, wire grids may be provided, e.g., formed, in the first regions320A, and wire grids may not be provided in the second regions320B. In such an embodiment, the first regions320A, in which wire grids are subsequently formed, and the second regions320B, in which no wire grid is subsequently formed, may be defined by a patterning process using the first mask M1. In one embodiment, for example, the patterning process may be performed by photolithography.

Next, wire grids may be formed in the first regions320A through a nanoimprinting process. In an embodiment, as shown inFIG. 13, in the nanoimprinting process, a first resin layer R1may be formed on the first mask M1. Then, the first resin layer R1is patterned using a first stamp S1. The first stamp S1may have a first pattern P1, and the first pattern P1may be transferred to the first resin layer R1to form a second pattern P2in the first resin layer R1. The second pattern P2may be sequentially formed in other regions of the first resin layer R1using the first stamp S1. Referring toFIG. 15, first wire grids325may be formed in the first regions320A by etching the first layer320using the second pattern P2and removing the first resin layer R1and the first mask M1. In such a process, when the first pattern P1of the first stamp S1is transferred to the first resin layer R1, lateral portions of the first resin layer R1may be pushed away, and thus the second pattern P2may be deformed. If the first regions320A are directly stamped using the first stamp S1in a state where the second regions320B is not provided between the first regions320A, e.g., in a state where the first regions320A are disposed adjacent to each other, the second pattern P2may be further deformed due to an adjacent second pattern P2. In an embodiment of the present invention, however, the second regions320B, in which no wire grid is formed, are provided adjacent to the first regions320A, and thus, deformation of the second pattern P2may be suppressed. In such an embodiment, the first wire grids325are formed in the first regions320A using the less-deformed second pattern P2of the first resin layer R1, such that defects caused by deformation of the first wire grids325may be reduced. In such an embodiment, since the second pattern P2is formed in the first resin layer R1corresponding to the first regions320A through a simple process using the first stamp S1, the first wire grids325may be rapidly formed in the first regions320A throughout a large area. In such a process, connection portions between the first regions320A may be deformed. However, according to an embodiment of the invention, the first regions320A are discontinuously arranged, such that the connection portions between the first regions320A may be minimized. Thus, when a wire grid polarizer having a large area is manufactured using such an embodiment of a method, defects caused by deformation may be substantially reduced.

Referring toFIG. 16, a first protection layer327may be formed on the first regions320A and the second regions320B. A second layer330may be formed on the first protection layer327. A second mask M2is disposed on the second layer330.

Referring toFIGS. 17 and 18, the second layer330may be patterned and etched based on a pattern of the second mask M2to form third regions330A and fourth regions330B. In such an embodiment, wire grids may be subsequently formed in the third regions330A, and no wire grid may be subsequently formed in the fourth regions330B. In such an embodiment, the third regions330A, in which wire grids are formed, and the fourth regions330B, in which no wire grid is formed, may be defined by a patterning process using the second mask M2. In one embodiment, for example, the patterning process may be performed by photolithography.

Next, wire grids may be formed in the third regions330A through a nanoimprinting process. As shown inFIG. 19, in the nanoimprinting process, a second resin layer R2may be formed on the second mask M2. Then, the second resin layer R2is patterned using a second stamp S2. The second stamp S2may have a third pattern P3, and the third pattern P3may be transferred to the second resin layer R2to form a fourth pattern P4in the second resin layer R2. The fourth pattern P4may be sequentially formed in other regions of the second resin layer R2using the second stamp S2. Referring toFIG. 21, second wire grids335may be formed in the third regions330A by etching the second layer330using the fourth pattern P4and removing the second resin layer R2and the second mask M1. In such a process, when the third pattern P3of the second stamp S2is transferred to the second resin layer R2, lateral portions of the second resin layer R2may be pushed away, and thus the fourth pattern P4may be deformed. If the third regions330A are directly stamped using the second stamp S2in a state where the fourth regions330B is not provided between the third regions330A, the fourth pattern P4may be further deformed due to an adjacent fourth pattern P4. In an embodiment of the invention, however, the fourth regions330B, in which wire grids are formed, are provided adjacent to the third regions330A, and thus, deformation of the fourth pattern P4may be suppressed. In an embodiment, the second wire grids335are formed in the third regions330A using the less-deformed fourth pattern P4, such that defects caused by deformation of the second wire grids335may be reduced. In such an embodiment, the fourth pattern P4is formed in the second resin layer R2corresponding to the third regions330A through a simple process using the second stamp S2, such that the second wire grids335may be rapidly formed in the third regions330A throughout a large area. In such a process, connection portions between the third regions330A may be deformed. However, according to an embodiment of the invention, the third regions330A are discontinuously arranged, such that the connection portions between the third regions330A may be minimized. Thus, when a wire grid polarizer having a large area is manufactured using such an embodiment of a method, defects caused by deformation may be reduced.

In an embodiment of the invention, as described above, the first regions320A and the second regions320B are defined or formed in the first layer320by patterning, and then the first wire grids325are discontinuously formed only in the first regions320A, thus suppressing deformation that may occur when the first wire grids325are formed in the first regions320A through a nanoimprinting process. In such an embodiment, the third regions330A and the fourth regions330B are defined or formed in the second layer330by patterning, and then the second wire grids335are discontinuously formed only in the third regions330A, thus suppressing deformation that may occur when the second wire grids335are formed in the third region330A through a nanoimprinting process. As described above, in such an embodiment, a first nanoimprinting process for discontinuously forming the first wire grids325and a second nanoimprinting process for discontinuously forming the second wire grids335may be separately performed, such that deformation caused by a nanoimprinting process may be reduced, and thus a wire grid polarizer having a large area may be effectively and efficiently manufactured.

An embodiment of the wire grid polarizers100and200illustrated inFIGS. 7 to 9, which have a three layer structure, may be manufactured through the nanoimprinting process described above with reference toFIGS. 14 to 22by forming an additional layer of wire grids thereon.

Next, another embodiment of a method of manufacturing a wire grid polarizer according to the invention will be described with reference toFIGS. 23 to 31.

Referring toFIG. 23, a first layer420is provided, e.g., disposed, on a substrate410, and a first mask M1is provided on the first layer420. The substrate410may be a transparent substrate that transmits light. In one embodiment, for example, the substrate410may be a glass substrate or a transparent plastic substrate. The first layer420may include or be formed of a metal. In one embodiment, for example, the first layer420may include aluminum (Al), silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt) or a combination thereof.

Referring toFIG. 24, the first layer420may be patterned and etched based on a pattern of the first mask M1to define first regions420A (refer toFIG. 25) and second regions EA on the substrate410. Subsequently, wire grids may be formed in the first regions420A, and no wire grid may be formed in the second regions EA. In such an embodiment, the first regions420A, in which wire grids are formed, and the second regions EA, in which no wire grid is formed, may be defined by a patterning process using the first mask M1. In one embodiment, for example, the patterning process may be performed by photolithography.

Next, referring toFIGS. 24 and 25, first wire grids425may be formed in the first regions420A through a nanoimprinting process. The nanoimprinting process is substantially the same as that described above with reference toFIGS. 13 and 14, and any repetitive detailed description thereof will be omitted.

In an embodiment, the first wire grids425are discontinuously formed by the nanoimprinting process, as described above, connection portions between the first wire grids425may be less deformed than a case where the first wire grids425are continuously formed.

Next, referring toFIG. 26, a first protection layer427may be formed on the first layer420. Thereafter, referring toFIGS. 26 and 27, the first protection layer427may be patterned using a mask M to form third regions EA2between the first regions420A. The third regions EA2may be substantially the same as the second regions EA. In such an embodiment, the first regions420A may be protected by the first protection layer427, and a portion of the substrate410corresponding to the third regions EA2may be exposed through the third regions EA2.

In such an embodiment, the first wire grids425are discontinuously formed, such that deformation that may occur when the first wire grids425are formed through the nanoimprinting process may be reduced.

Next, referring toFIG. 28, a second layer430is provided, e.g., disposed, on the third regions EA2. The second layer430may be disposed only on the third regions EA2using a mask M. The second layer430may include a metal. In one embodiment, for example, the second layer420may include aluminum (Al), silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt) or a combination thereof.

A second mask M2is disposed on the second layer430. Referring toFIG. 29, a second resin layer R2may be disposed on the second mask M2, and second wire grids435may be formed in the third regions EA2through a nanoimprinting process. In such a process, if the second resin layer R2is deformed, the second wire grids435formed by etching the second resin layer R2may also be deformed. In an embodiment, as shown inFIG. 29, the second resin layer R2is discontinuously formed, such that deformation of the second resin layer R2may be reduced. Thus, deformation of the second wire grids435may be reduced.

Referring toFIG. 31, a second protection layer437may further be formed to protect the first wire grids425and the second wire grids435. In such an embodiment, the first wire grids425and the second wire grids435may be formed in a same layer as each other.

According to an embodiment of a wire grid polarizer manufacturing method of the invention, a first nanoimprinting process for forming first wire grids and a second nanoimprinting process for forming second wire grids may be separately performed in different regions. Therefore, in such an embodiment, deformation that may be caused when a nanoimprinting process is performed in a continuous region may be reduced. In such an embodiment of the wire grid polarizer manufacturing method, a wire grid polarizer having a large area may be effectively and efficiently manufactured through nanoimprinting processes, and the productivity of manufacturing processes thereof may be improved.

It should be understood that exemplary embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.