KR20090054746A - Optical retarder film and method of manufacturing for the same and display device using the same - Google Patents

Abstract

An optical phase retardation film, a manufacturing method thereof and a display device including the same are provided to align adjacent LC molecules as rotating pre-polarized light at 90 degrees or changing the light into circular polarization light or elliptic polarization light. An optical phase retardation film(500) comprises projection line patterns(510,520) having LC(Liquid Crystal) orientation. The projection line pattern has a phase difference within a range of 0~lambda/2 and is made from photo-curable LC polymer. Through the LC orientation, the plural projection line patterns align LC molecules(301,302) which will be disposed to be adjacent. The plural projection line patterns have different longitudinal directions. The plural projection line patterns include a first projection line pattern having anisotropy and a second projection line pattern having isotropy where a phase difference is zero.

Description

Optical phase retardation film, a manufacturing method thereof, and a display device having the same {OPTICAL RETARDER FILM AND METHOD OF MANUFACTURING FOR THE SAME AND DISPLAY DEVICE USING THE SAME}

The present invention relates to an optical phase retardation film, a method of manufacturing the same, and a display device having the same, and more particularly, to an optical phase retardation film that rotates linearly polarized light by 90 degrees or converts it into circularly or elliptically polarized light. A method and a display device having the same.

There are several types of display devices. Due to the rapidly developing semiconductor technology, liquid crystal display (LCD) devices having improved performance, miniaturization, and weight are becoming representative display devices.

Liquid crystal displays have been attracting attention as an alternative means of overcoming the disadvantages of conventional cathode ray tubes (CRTs) because they have advantages such as miniaturization, light weight, and low power consumption. Nowadays, almost all information processing needs are needed, such as those used in small and medium products such as mobile phones, personal digital assistants (PDAs), and portable multimedia players (PMPs) that require display devices, as well as monitors and TVs. It is attached to the apparatus and used.

Among them, in particular, liquid crystal displays mounted on small products such as mobile phones, PDAs, and PMPs are formed in a reflective or semi-transmissive type in order to save power and improve brightness and contrast ratio. It includes a reflective film formed inside to reflect an external light to display an image. In addition, the reflective or transflective liquid crystal display includes an optical phase retardation film that rotates linearly polarized light through a polarizing plate by 90 degrees or converts it into circularly polarized or elliptical polarized light.

The transmissive liquid crystal display may also include a photophase retardation film, if necessary.

The optical phase retardation film may have various phase differences depending on the type of the liquid crystal display and the position used.

However, the conventional optical phase retardation film has a complicated manufacturing process, which causes a decrease in the productivity of the overall liquid crystal display device. In addition, the conventional photophase retardation film was formed separately from the alignment film for orienting the liquid crystal molecules of the liquid crystal layer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an optical phase retardation film that rotates linearly polarized light by 90 degrees or converts circularly polarized or elliptically polarized light and orients adjacent liquid crystal molecules.

In addition, the present invention is to solve the problems of the above-described background, to provide a manufacturing method that can easily and efficiently produce the above-described optical phase retardation film.

In addition, the present invention is to solve the above problems of the background art, to provide a display device having the above-described optical phase retardation film.

The photophase retardation film according to the present invention comprises a plurality of projection line patterns made of a photocurable liquid crystal polymer and having a phase difference within a range of 0 to λ / 2, wherein the plurality of projection line patterns align liquid crystal molecules to be adjacently disposed. It has liquid crystal aligning property to make.

The plurality of protrusion line patterns may have different length directions.

The plurality of protruding line patterns may include a first protruding line pattern having a first direction and a second protruding line pattern having a second direction different from the first direction. The piers in the direction may be 45 degrees.

The plurality of protrusion line patterns may have different phase differences.

The plurality of protrusion line patterns may include a first protrusion line pattern having anisotropy and a second protrusion line pattern having an isotropy having a zero phase difference.

In the optical phase retardation film, the long axis direction of the liquid crystal molecules to be adjacently disposed may be horizontally aligned so as to be substantially parallel to the longitudinal direction of the plurality of protrusion line patterns in the electric field member state.

In addition, in the optical phase retardation film, the long axis direction of the liquid crystal molecules to be adjacently disposed may be vertically aligned so as to substantially parallel with the rising direction of the plurality of protrusion line patterns in the electric field member state.

The plurality of protrusion line patterns may be silane-treated on a surface thereof.

In addition, the method for manufacturing a photophase retardation film according to the present invention comprises the steps of coating a photocurable liquid crystal polymer layer on a substrate, and imprinting the photocurable liquid crystal polymer layer with a polymer mold having a plurality of recessed line patterns. (imprinting) and irradiating unpolarized ultraviolet rays to the imprinted photocurable liquid crystal polymer layer.

The photocurable liquid crystal polymer layer has a plurality of projection line patterns corresponding to the recessed line patterns of the polymer mold, and the plurality of projection line patterns have a phase difference within a range of 0 to λ / 2, and have different length directions. Can have

The plurality of protruding line patterns may include a first protruding line pattern having a first direction and a second protruding line pattern having a second direction different from the first direction. The piers of can be 45 degrees.

The coating is spin coating, the higher the speed of the coating, the closer the phase difference of the plurality of protrusion line patterns is to λ / 2, and the higher the concentration of the photocurable liquid crystal polymer layer, the more the plurality of dolly line patterns The phase difference can be close to zero.

In addition, another method of manufacturing a photo phase retardation film according to the present invention comprises coating a photocurable liquid crystal polymer layer on a substrate, and imprinting the photocurable liquid crystal polymer layer with a polymer mold having a recessed line pattern ( imprinting), irradiating ultraviolet light which is not selectively polarized by using a mask to one region of the imprinted photocurable liquid crystal polymer layer, and the photocurable liquid crystal polymer layer having one region exposed to ultraviolet light Applying heat to have a moderated temperature.

The method may further include irradiating the non-polarized ultraviolet rays to the heated photocurable liquid crystal polymer layer as a whole.

The preset temperature may be 180 degrees Celsius or more.

The photocurable liquid crystal polymer layer has a projection line pattern corresponding to the recessed line pattern of the polymer mold, and the projection line pattern is formed on one region of the photocurable liquid crystal polymer layer selectively exposed to ultraviolet light using the mask. A first projection line pattern having a corresponding anisotropy and a second projection line pattern having anisotropy corresponding to other regions of the photocurable liquid crystal polymer layer not selectively exposed to ultraviolet rays by using the mask; The protruding line pattern may have a phase difference within a range greater than 0 and less than or equal to λ / 2, and the second protruding line pattern may have a phase difference of zero.

The coating is spin coating, the higher the speed of the coating, the closer the phase difference of the plurality of protrusion line patterns is to λ / 2, and the higher the concentration of the photocurable liquid crystal polymer layer, the more the plurality of dolly line patterns The phase value can be close to zero.

The method may further include silane-treating the surface of the photocurable liquid crystal polymer layer.

In addition, the display device according to the present invention includes a first substrate, a second substrate facing the first substrate, a liquid crystal layer disposed between the first substrate and the second substrate and including a plurality of liquid crystal molecules, A photophase retardation film disposed at at least one position between one substrate and said liquid crystal layer and between said second substrate and said liquid crystal layer, said photophase retardation film being made of a photocurable liquid crystal polymer and having from 0 to lambda / 2 Including a plurality of projection line patterns having a phase difference within a range, the plurality of projection line patterns may have a liquid crystal alignment to orient the liquid crystal molecules of the liquid crystal layer.

The plurality of protrusion line patterns may have different length directions.

The plurality of protruding line patterns may include a first protruding line pattern having a first direction and a second protruding line pattern having a second direction different from the first direction. The piers in the direction may be 45 degrees.

The plurality of protrusion line patterns may have different phase differences.

The plurality of protrusion line patterns may include a first protrusion line pattern having anisotropy and a second protrusion line pattern having an isotropy having a zero phase difference.

In the display device, the long axis direction of the liquid crystal molecules may be horizontally aligned so as to be substantially parallel to the length direction of the plurality of protrusion line patterns in the electric field member state.

In the display device, the long axis direction of the liquid crystal molecules may be vertically aligned so as to be substantially parallel to the rising direction of the plurality of protrusion line patterns in the electric field member state.

The plurality of protrusion line patterns may be silane-treated on a surface thereof.

According to the present invention, the optical phase retardation film can rotate linearly polarized light 90 degrees or convert circularly polarized light or elliptical polarized light and orient adjacent liquid crystal molecules.

That is, the optical phase retardation film may selectively adjust an area for rotating the linearly polarized light by 90 degrees or converting the circularly polarized light or the elliptical polarized light as needed. Therefore, it is possible to minimize the decrease in the overall brightness and contrast ratio is absorbed by the polarizing plate.

In addition, since the liquid crystal alignment properties of the adjacent liquid crystal molecules are aligned, the role of the alignment layer may be performed together.

In addition, according to the present invention, the above-described optical phase retardation film can be easily and efficiently produced.

In addition, according to the present invention, it is possible to provide a display device having the above-described optical phase retardation film.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In addition, in the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a portion of a layer, film, region, plate, or the like is said to be "on" or "on" another portion, this includes not only when the other portion is "right over" but also when there is another portion in the middle. On the contrary, when a part is "just above" another part, there is no other part in the middle.

In addition, the optical phase retardation film and the display device having the same are not limited to the structure shown in the accompanying drawings, and may have various structures within a range that can be easily changed by those skilled in the art.

In order to clearly describe the present invention, parts irrelevant to the description are omitted, and like reference numerals designate like elements throughout the specification.

In addition, in the various embodiments, components having the same configuration will be described in the first embodiment by using the same reference numerals, and in other embodiments, only the configuration different from the first embodiment will be described.

Example 1

A first embodiment according to the present invention will be described with reference to FIGS.

1 is a perspective view of an optical phase retardation film 500 according to a first embodiment of the present invention. In FIG. 1, reference numeral 101 denotes a substrate on which the optical phase retardation film 500 is formed. As shown in FIG. 1, the optical phase retardation film 500 includes a film main body 550 and a plurality of protrusion line patterns 510 and 520 formed on the film main body 550. The protruding line patterns 510 and 520 respectively include a plurality of raised lines 511 and 521 and a plurality of goal lines 512 and 522 positioned between the raised lines 511 and 521.

The plurality of protrusion line patterns 510 and 520 have different length directions. That is, the plurality of protrusion line patterns 510 and 520 may include a first protrusion line pattern 510 having a length direction in a first direction and a second protrusion line pattern 520 having a length direction in a second direction different from the first direction. ). Here, the piers in the first direction and the second direction are 45 degrees. Here, the length direction refers to the direction of the grain formed by the rising lines 511 and 521 and the goal lines 512 and 522 of the protruding line patterns 510 and 520.

In addition, although the first protrusion line pattern 510 and the second protrusion line pattern 520 are alternately arranged in FIG. 1, the present invention is not necessarily limited thereto. Therefore, the first protrusion line pattern 510 and the second protrusion line pattern 520 may be freely arranged in various shapes as necessary, and the area of the first phase protrusion line pattern 510 of the optical phase retardation film 500 may be provided. The area of the second protrusion line pattern 520 may also be freely set as necessary.

In addition, the optical phase retardation film 500 may include polarizing plates 150 and 250 (shown in FIG. 12) of the display device 900 provided with the optical phase retardation film 500 in either of the first direction and the second direction. It is substantially the same as the polarization axis which it has, and the other direction of a 1st direction and a 2nd direction is arrange | positioned inside the display apparatus 900 so that the pier of a polarization axis may be 45 degree | times.

In addition, the plurality of protrusion line patterns 510 and 520 have a phase difference within a range of 0 to λ / 2. Specifically, the phase difference of the protruding line patterns 510 and 520 is 0, λ / 4 according to the type of the display device in which the optical phase retardation film 500 is used and the position where the optical phase retardation film 500 is disposed. Or, it may have a phase difference of λ / 2, and in some cases, may have various phase differences within a range from 0 to λ / 2.

In addition, the plurality of protrusion line patterns 510 and 520 have the same phase difference with each other. However, the present invention is not necessarily limited thereto. Therefore, the plurality of protrusion line patterns 510 and 520 having different length directions may have different phase differences.

In addition, the plurality of protrusion line patterns 510 and 520 have a liquid crystal alignment property to orient liquid crystal molecules to be adjacently disposed. The protruding line patterns 510, 520 comprising raised lines 511, 521 and goal lines 512, 522 align structurally adjacent liquid crystal molecules. That is, the liquid crystal molecules are aligned along the grain direction of the protruding line patterns 510 and 520. Therefore, the optical phase retardation film 500 according to the present invention may also serve as an alignment layer.

Reference numerals 301 and 302 in FIG. 1 illustrate liquid crystal molecules oriented by the protruding line patterns 510 and 520 of the optical phase retardation film 500. Reference numeral 301 denotes liquid crystal molecules horizontally aligned by the protruding line patterns 510 and 520 of the photophase retardation film 500, and reference numeral 302 denotes vertically aligned liquid crystal molecules.

The protruding line patterns 510 and 520 structurally align the liquid crystal molecules 301. That is, the long axis direction of the liquid crystal molecules 301 is oriented substantially parallel to the longitudinal direction of the protruding line patterns 510 and 520 in the electric field member state.

However, the present invention is not necessarily limited thereto. Therefore, the protruding line patterns 510 and 520 may vertically align the liquid crystal molecules 302. That is, the long axis direction of the liquid crystal molecules 302 is oriented substantially parallel to the rising direction of the protruding line patterns 510 and 520, specifically, the rising direction of the rising lines 511 and 521 in the electric field member state. However, in order for the projection line patterns 510 and 520 to vertically align the liquid crystal molecules 302, the surface of the projection line patterns 510 and 520 must be loaded. Silane treatment refers to coating an affinity silane material on the surface of the protruding line patterns 510 and 520. The silane treatment can be used a variety of known treatment methods that can be easily carried out by those skilled in the art.

(If you can explain the silane treatment, please ask.)

In addition, since the first protrusion line pattern 510 and the second protrusion line pattern 520 align the liquid crystal molecules in different directions, the first protrusion line pattern 510 and the second protrusion line pattern 520 may be used. Multi-domains for dividing one pixel into a plurality of domains may be formed. A pixel refers to a minimum unit in which a display device displays an image.

In addition, the photophase retardation film 500 is made of a photocurable liquid crystal polymer. The photocurable liquid crystal polymer refers to a liquid crystal phase polymer that is cured when irradiated with light such as ultraviolet rays. As the photocurable liquid crystal polymer, various kinds known in the art can be easily used by those skilled in the art.

(If possible, please explain the types and components of photocurable liquid crystal polymer.)

2A and 2B show the results of observing the optical phase retardation film 500 disposed between a pair of polarizing plates where the polarization axes intersect with an electron microscope.

2A and 2B, reference numeral AP denotes directions of a polarization axis of a pair of polarizing plates. Reference numeral A51 denotes a first direction which is the longitudinal direction of the first protrusion line pattern 510, and reference numeral A52 denotes a second direction which is the longitudinal direction of the second protrusion line pattern 520. 2A and 2B, the first protrusion line pattern 510 and the second protrusion line pattern 520 have a phase difference of λ / 4.

2A illustrates a length direction of the second protrusion line pattern 520, that is, the second direction A52 coincides with one of the polarization axis directions AP of the pair of polarizing plates, and FIG. 2B illustrates the first protrusion line pattern ( The length direction of the 510, that is, the first direction A51 coincides with one of the polarization axis directions AP of the pair of polarizing plates. FIG. 2B rotates the optical phase retardation film 500 of FIG. 2A by 45 degrees.

As shown in FIG. 2A and FIG. 2B, the protrusion line patterns 510 and 520 having the same length direction as one of the polarization axis directions AP of the pair of polarizers do not pass light and appear dark. The projection line patterns 510 and 520 intersecting the polarization axis directions AP of the pair of polarizing plates at an angle of 45 degrees are brightly displayed through the light. 2A and 2B show inverted aspects. The first protrusion line pattern 510 and the second protrusion line pattern 520 rotate the light linearly polarized by the polarizer by a polarizing plate with a phase difference of λ / 4 by 90 degrees or convert to circularly or elliptically polarized light. Therefore, when the length direction of the protruding line patterns 510 and 520 coincides with one of the polarization axis directions of the polarizing plate, light does not pass back to the polarizing plate and becomes dark.

3 is a graph illustrating a result of measuring optical anisotropy values of the optical phase retardation film 500 of FIG. 1. As shown in FIG. 3, the first protrusion line pattern 510 and the second protrusion line pattern 520 have different optical axes. That is, the first protrusion line pattern 510 and the second protrusion line pattern 520 both have a phase difference of λ / 4, and show only 45 degrees in the direction thereof.

By such a configuration, the optical phase retardation film 500 may selectively adjust an area for rotating the linearly polarized light by 90 degrees or converting the circularly polarized light or the elliptical polarized light. Therefore, it is possible to minimize the decrease in the overall brightness and contrast ratio is absorbed by the polarizing plate.

Here, when the projection line patterns 510 and 520 of the optical phase retardation film 500 have a phase difference of λ / 4, linearly polarized light is circularly polarized. When the protrusion line patterns 510 and 520 have a phase difference of λ / 2, the linearly polarized light is converted into linearly polarized light rotated by 90 degrees. If the projection line patterns 510 and 520 have other phase differences, the linearly polarized light is elliptically polarized.

In addition, since the liquid crystal alignment properties of the adjacent liquid crystal molecules are aligned, the role of the alignment layer may be performed together.

In addition, the multi-domain may be formed using the first protrusion line pattern 510 and the second protrusion line pattern 520 having different length directions.

Hereinafter, a method of manufacturing the optical phase retardation film 500 of FIG. 1 according to the first embodiment of the present invention will be described with reference to FIGS. 4 and 5.

First, as shown in FIG. 4, the photocurable liquid crystal polymer layer 501 is coated on the substrate 101. Here, the coating uses a spin coating method. However, the present invention is not necessarily limited thereto, and various known coating methods may be used.

The photocurable liquid crystal polymer layer 501 is imprinted with the polymer mold 700. Here, the polymer mold 700 has a plurality of recessed line patterns 710 and 720. The recessed line pattern includes a first recessed line pattern 710 and a second recessed line pattern 720. The first recessed line pattern 710 forms the first protrusion line pattern 510 of the optical phase retardation film 500, and the second recessed line pattern 720 is the second protrusion line of the optical phase retardation film 500. Pattern 520 is formed. In addition, the polymer mold 700 has heat resistance and is made of a transparent resin-based material.

(If you can explain the material of the polymer mold, please ask.)

Next, as shown in FIG. 5, unpolarized ultraviolet rays are irradiated onto the imprinted photocurable liquid crystal polymer layer 502, that is, the photocurable liquid crystal polymer layer 502 bonded to the polymer mold 700. At this time, since the polymer mold 700 is transparent, ultraviolet light can be freely irradiated from various aspects. The photocurable liquid crystal polymer layer 502 is cured by receiving ultraviolet rays.

Next, when the polymer mold 700 is separated, the optical phase retardation film 500 having the first protrusion line pattern 510 and the second protrusion line pattern 520 is formed.

In this case, the first protrusion line pattern 510 and the second protrusion line pattern 520 may be adjusted in the process of manufacturing the optical phase retardation film to have a desired phase difference within a range of 0 to λ / 2. Specifically, in the process of coating the photocurable liquid crystal polymer layer 501 on the substrate 101 through spin coating, the higher the coating speed is, the more the phase difference between the protruding line patterns 510 and 520 is λ / 2. Getting closer. On the other hand, as the concentration of the photocurable liquid crystal polymer layer 501 is higher, the phase difference of the protruding line patterns 510 and 520 becomes closer to zero.

By such a manufacturing method, it is possible to easily and efficiently produce an optical phase retardation film 500 capable of rotating linearly polarized light by 90 degrees or converting circularly polarized or elliptically polarized light and orienting adjacent liquid crystal molecules. .

In addition, after coating the photocurable liquid crystal polymer layer 501 on the substrate 101, the method may further include a silane treatment on the surface of the photocurable liquid crystal polymer layer 501. When the surface of the photocurable liquid crystal polymer layer 501 is silane-treated, adjacent liquid crystal molecules may be vertically aligned by the photophase retardation film 500. Meanwhile, after the optical phase retardation film 500 is formed, a silane treatment may be performed on the surfaces of the first protrusion line pattern 510 and the second protrusion line pattern 520.

Example 2

6 to 8, a second embodiment according to the present invention will be described.

6 is a perspective view of the optical phase retardation film 600 according to the second embodiment of the present invention. In FIG. 6, reference numeral 101 denotes a substrate on which an optical phase retardation film is formed. As shown in FIG. 6, the optical phase retardation film 600 includes a film main body 650 and a plurality of protrusion line patterns 610 and 620 formed on the film main body 650.

The plurality of protrusion line patterns 610 and 620 have different phase differences. That is, the plurality of protrusion line patterns may include a first protrusion line pattern 610 having anisotropy and a second protrusion line pattern 620 having isotropy. Here, the first protrusion line pattern 610 has a phase difference within a range larger than 0 and smaller than or equal to λ / 2. Specifically, the phase difference of the first protrusion line pattern 610 is λ / 4 or λ / It may have a phase difference of 2, and in some cases, may have various phase differences within a range greater than 0 and less than or equal to λ / 2. In addition, the phase difference of the second protrusion line pattern 620 is zero.

In addition, although the first protrusion line pattern 610 and the second protrusion line pattern 620 are alternately arranged in FIG. 6, the present invention is not necessarily limited thereto. Accordingly, the first protrusion line pattern 610 and the second protrusion line pattern 620 may be freely arranged in various shapes as necessary, and the area of the first protrusion line pattern 610 of the optical phase retardation film 600 may be provided. The area of the second projection line pattern 620 may also be freely set as necessary.

The optical phase retardation film 600 including the first projection line pattern 610 and the second projection line pattern 620 having different phase differences may have a reflection area and a transmission area at the same time as a transflective liquid crystal display. It can be effectively used for existing display devices.

In addition, the plurality of protrusion line patterns 610 and 620 have substantially the same length direction. However, the present invention is not necessarily limited thereto. Therefore, the plurality of protrusion line patterns 610 and 620 having different phase differences may be formed to have different length directions.

In addition, the plurality of protruding line patterns 610 and 620 have a liquid crystal alignment property to orient liquid crystal molecules to be adjacently disposed. That is, the liquid crystal molecules are aligned along the grain direction of the protruding line patterns 610 and 620. Therefore, the optical phase retardation film 600 according to the present invention may also serve as an alignment layer. In this case, the protrusion line patterns 610 and 620 structurally align the liquid crystal molecules. However, the surface-silane-treated protrusion line patterns 610 and 620 may vertically align the liquid crystal molecules.

In addition, the photophase retardation film 600 is made of a photocurable liquid crystal polymer. The photocurable liquid crystal polymer refers to a liquid crystal phase polymer that is cured when irradiated with light such as ultraviolet rays. As the photocurable liquid crystal polymer, various kinds known in the art can be easily used by those skilled in the art.

7A and 7B show the results of observing the optical phase retardation film 600 disposed between a pair of polarizing plates where the polarization axes intersect with an electron microscope.

7A and 7B, reference numeral AP denotes directions of a polarization axis of a pair of polarizing plates. Reference numerals A61 and A62 denote the longitudinal directions of the first protrusion line pattern 610 and the second protrusion line pattern 620. 2A and 2B, the first protrusion line pattern 620 has a phase difference of λ / 4, and the second protrusion line pattern 620 has a phase difference of zero.

FIG. 7A illustrates that the length directions of the first protrusion line pattern 610 and the second protrusion line pattern 620 are inconsistent with the polarization axis directions of the pair of polarizers, and FIG. 7B illustrates the first protrusion line pattern 610 and the first protrusion line pattern 610. The longitudinal direction of the two-protrusion line pattern 620 coincides with one of the polarization axis directions of the pair of polarizing plates. FIG. 7B rotates the optical phase retardation film 600 of FIG. 7A by 45 degrees.

As shown in FIG. 7A, when the length directions of the first protrusion line pattern 610 and the second protrusion line pattern 620 are inconsistent with the polarization axis directions of the pair of polarizing plates, the first protrusion line pattern having anisotropy 610 is brightly displayed through the light, and the second projection line pattern 620 having isotropy is dark because it cannot pass the light.

On the other hand, as shown in FIG. 7B, when the length direction of the first protrusion line pattern 610 and the second protrusion line pattern 620 coincides with one of the polarization axis directions of the pair of polarizing plates, the first anisotropy is performed. Both the protruding line pattern 610 and the isotropic second protruding line pattern 620 do not pass through the light and are darkened. The first protrusion line pattern 610 rotates the light linearly polarized by the polarizing plate with a phase difference of λ / 4 by 90 degrees or converts the circularly polarized or elliptical polarized light. Therefore, when the length direction of the first protrusion line pattern 610 coincides with one of the polarization axis directions of the polarizing plate, light does not pass back to the polarizing plate and becomes dark.

8 is a graph illustrating a result of measuring optical anisotropy values of the optical phase retardation film 600 of FIG. 6. As shown in FIG. 8, the first protrusion line pattern 610 has a phase difference of λ / 4, and the second protrusion line pattern 620 has a phase difference of zero.

By such a configuration, the optical phase retardation film 600 may selectively adjust an area for rotating the linearly polarized light by 90 degrees or converting the circularly polarized light or the elliptical polarized light as necessary. Therefore, it is possible to minimize the decrease in the overall brightness and contrast ratio is absorbed by the polarizing plate.

In addition, since the liquid crystal alignment properties of the adjacent liquid crystal molecules are aligned, the role of the alignment layer may be performed together.

In addition, the optical phase retardation film 600 including the first projection line pattern 610 and the second projection line pattern 620 having different phase differences may have a reflection area and a transmission area therein like a transflective liquid crystal display. It can be used more effectively for the display devices that exist at the same time.

Hereinafter, a method of manufacturing the optical phase retardation film 600 of FIG. 6 according to a second embodiment of the present invention will be described with reference to FIGS. 9 to 11.

First, as shown in FIG. 9, the photocurable liquid crystal polymer layer 601 is coated on the substrate 101. Here, the coating uses a spin coating method. However, the present invention is not necessarily limited thereto, and various known coating methods may be used.

Then, the photocurable liquid crystal polymer layer 601 is imprinted with the polymer mold 800. Here, the polymer mold 800 has a recessed line pattern 830. The recessed line pattern 830 forms protrusion line patterns 610 and 620 of the optical phase retardation film 600. In addition, the polymer mold 800 has heat resistance and is made of a transparent resin-based material.

Next, as illustrated in FIG. 10, the polarized light is selectively polarized using a mask 850 on the imprinted photocurable liquid crystal polymer layer 602, that is, the photocurable liquid crystal polymer layer 602 bonded to the polymer mold 800. Irradiate with untreated ultraviolet rays. That is, one region of the photocurable liquid crystal polymer layer 602 is cured by being irradiated with ultraviolet rays, and the other region is not irradiated with ultraviolet rays. At this time, since the polymer mold 800 is transparent, ultraviolet rays can be freely irradiated from various aspects. The mask 850 includes an opening region 852 that transmits light and a shielding region 851 that blocks light.

Next, one region heats the photocurable liquid crystal polymer layer 602 exposed to ultraviolet rays. Specifically, the other uncured region of the photocurable liquid crystal polymer layer 6002 is heated above the temperature at which it is transferred to an isotropic phase. Therefore, one region of the photocurable liquid crystal polymer layer 602 cured by being exposed to ultraviolet rays maintains anisotropy, and the other region receives heat in an uncured state and is transferred to an isotropic phase. The isotropic transition temperature of the photocurable liquid crystal polymer layer 602 can be measured using a measuring apparatus such as a differential analyzer (differentail scanning calorimeter, DSC). Here, in order for the other region of the photocurable liquid crystal polymer layer 602 to transition to isotropic phase, the temperature should be at least 180 degrees Celsius or more.

Next, as shown in FIG. 11, when the other regions of the photocurable liquid crystal polymer layer 602 are transferred to an isotropic phase, the photocurable liquid crystal polymer layer 602 is entirely exposed to unpolarized ultraviolet rays.

Next, when the polymer mold 800 is separated, an optical phase retardation film 600 having a first protrusion line pattern 610 and a second protrusion line pattern 620 is formed.

At this time, one region of the photocurable liquid crystal polymer layer 602 having anisotropy by being selectively exposed to ultraviolet rays through the mask 800 becomes the first protrusion line pattern 610 of the photophase retardation film 600, and is heated. The other region of the photocurable liquid crystal polymer layer 602 transferred to an isotropic phase becomes the second protrusion line pattern 620 of the optical phase retardation film. Here, the first protrusion line pattern 610 has a phase difference within a range larger than 0 and smaller than or equal to λ / 2. The phase difference of the second protrusion line pattern 620 is zero.

In addition, the first protrusion line pattern 610 may be adjusted in the process of manufacturing the photophase retardation film to have a desired phase difference within a range larger than 0 and smaller than or equal to λ / 2. Specifically, in the process of coating the photocurable liquid crystal polymer layer 601 on the substrate through spin coating, the higher the coating speed, the closer the phase difference of the first protrusion line pattern 610 is to λ / 2. On the other hand, as the concentration of the photocurable liquid crystal polymer layer 601 increases, the phase difference of the first protrusion line pattern 610 is relatively close to zero.

By such a manufacturing method, it is possible to easily and efficiently produce an optical phase retardation film 600 capable of rotating linearly polarized light by 90 degrees or converting circularly polarized or elliptically polarized light and orienting adjacent liquid crystal molecules. .

The method may further include a process of silane-treating the surface of the photocurable liquid crystal polymer layer after coating the photocurable liquid crystal polymer layer on the substrate. On the other hand, after the optical phase retardation film is formed, a silane treatment may be performed on the surfaces of the first projection line pattern and the second projection line pattern. When the surface of the photocurable liquid crystal polymer layer is silane-treated, adjacent liquid crystal molecules may be vertically aligned by the photophase retardation film.

Example 3

A third embodiment according to the present invention will be described with reference to FIG. 12 is a schematic partial perspective view illustrating a structure of a display device 900 according to a third exemplary embodiment of the present invention.

As illustrated in FIG. 12, the display device 900 may include a first substrate 100, a second substrate 200, a liquid crystal layer 300, a first polarizing plate 150, a second polarizing plate 250, and an alignment layer ( 230 and an optical phase retardation film 500. Here, the optical phase retardation film 500 is the same as described in the first embodiment and the second embodiment.

The first substrate 100 includes a thin film transistor (TFT), which is a switching element, and a pixel electrode connected to the thin film transistor.

The second substrate 200 includes a common electrode. The color filter is formed on one of the first and second substrates 100 and 200.

At least one of the pixel electrode of the first substrate 100 and the common electrode of the second substrate 200 may have a partially or entirely reflective region. Thus, the display device 900 may be transflective or reflective. The reflective regions of the electrodes can be made of a material comprising aluminum, silver and other reflective materials.

The liquid crystal layer 300 includes a plurality of liquid crystal molecules 301 and is disposed between the pixel electrode of the first substrate 100 and the common electrode of the second substrate 200. The liquid crystal molecules 9301 may be horizontally or vertically aligned according to the type of the display device 900.

The first polarizing plate 150 and the second polarizing plate 250 are disposed outside the first substrate 100 and the second substrate 200 so that the polarization axes cross each other. The first polarizer 150 and the second polarizer 250 linearly polarize the light passing therethrough.

The optical phase retardation film 500 rotates the linearly polarized light by 90 degrees or converts the circularly polarized light into circularly or elliptically polarized light, and simultaneously orients the liquid crystal molecules 301 of the liquid crystal layer together with the alignment layer 230.

In addition, the optical phase retardation film 500 may selectively adjust a region for rotating the linearly polarized light by 90 degrees or converting the circularly polarized light or the elliptical polarized light as necessary. Therefore, light may be absorbed by the polarizers 150 and 250, thereby minimizing the decrease in overall luminance and contrast ratio.

In addition, the optical phase retardation film 500 may form a multi-domain in which one pixel is divided into a plurality of domains by differently adjusting the alignment directions of the liquid crystal molecules 301 of the liquid crystal layer 300.

With this configuration, when the thin film transistor is turned on, an electric field is formed between the pixel electrode and the common electrode. Due to such an electric field, the arrangement angle of the liquid crystal molecules of the liquid crystal layer disposed between the first substrate 100 and the second substrate 200 is changed, and thus the light transmittance is changed for each pixel in the display device 900.

In addition, the display device may include an optical phase retardation film capable of rotating the linearly polarized light by 90 degrees or converting the linearly polarized light into circularly or elliptically polarized light and aligning the liquid crystal molecules of the liquid crystal layer, thereby improving productivity.

In addition, the display device may increase light utilization efficiency and reduce waste.

In addition, the internal structure of the display device is not necessarily limited to those described above, and may have various structures known in the range that can be easily changed by those skilled in the art.

Although the present invention has been described through various embodiments as described above, those skilled in the art to which the present invention pertains can make various modifications and changes without departing from the concept and scope of the claims. Will easily understand.

1 is a perspective view of an optical phase retardation film according to a first embodiment of the present invention.

2A and 2B are views showing a state in which the optical phase retardation film of FIG. 1 is observed with an electron microscope.

3 is a graph showing the measurement of the optical anisotropy value of the optical phase difference retardation film of FIG.

4 and 5 are a perspective view and a cross-sectional view sequentially showing a manufacturing method of the optical phase retardation film of FIG.

6 is a perspective view of an optical phase retardation film according to a second exemplary embodiment of the present invention.

7A and 7B are views showing a state in which the optical phase retardation film of FIG. 7 is observed with an electron microscope.

FIG. 8 is a graph illustrating measurement of optical anisotropy values of the optical phase retardation film of FIG. 6.

9 to 11 are perspective views and cross-sectional views sequentially illustrating a method of manufacturing the optical phase retardation film of FIG. 6.

12 is a partial perspective view of a display device according to a third exemplary embodiment of the present invention.

Claims (26)

A plurality of projection line patterns made of a photocurable liquid crystal polymer and having a phase difference within a range of 0 to λ / 2, And the plurality of protruding line patterns have liquid crystal alignment to orient liquid crystal molecules to be adjacently arranged. In claim 1, And the plurality of protruding line patterns have different length directions. In claim 2, The plurality of protrusion line patterns, A first projection line pattern having a longitudinal direction in a first direction, A second projection line pattern having a second direction different from the first direction in a longitudinal direction; The pier in the first direction and the second direction is 45 degrees, characterized in that the optical phase retardation film. In claim 1, And the plurality of protruding line patterns have different phase differences. In claim 4, The plurality of protrusion line patterns, A first projection line pattern having anisotropy, And a second projection line pattern having an isotropy of zero phase difference. The method according to any one of claims 1 to 5, And the long-axis direction of the liquid crystal molecules to be adjacently arranged is horizontally oriented so as to be substantially parallel to the longitudinal direction of the plurality of protrusion line patterns in an electric field member state. The method according to any one of claims 1 to 5, And the long-axis direction of the liquid crystal molecules to be adjacently arranged is vertically aligned so as to be substantially parallel to the rising direction of the plurality of protrusion line patterns in the electric field member state. In claim 7, The plurality of protruding line patterns are optical phase retardation film, characterized in that the surface is silane-treated. Coating a photocurable liquid crystal polymer layer on the substrate; Imprinting the photocurable liquid crystal polymer layer with a polymer mold having a plurality of recessed line patterns; And irradiating unpolarized ultraviolet rays to the imprinted photocurable liquid crystal polymer layer. In claim 9, The photocurable liquid crystal polymer layer is formed with a plurality of protrusion line patterns corresponding to the recessed line patterns of the polymer mold, The plurality of protruding line patterns have a phase difference within a range from 0 to λ / 2, and have a different length direction. In claim 10, The plurality of protrusion line patterns, A first projection line pattern having a longitudinal direction in a first direction, A second projection line pattern having a second direction different from the first direction in a longitudinal direction; The bridge in the first direction and the second direction is 45 degrees, characterized in that the optical phase retardation film production method. In claim 9, The coating is spin coating, The higher the speed of the coating, the closer the phase difference of the plurality of projection line patterns is to λ / 2, The higher the density | concentration of the said photocurable liquid crystal polymer layer, the phase difference which a plurality of dolly line patterns have becomes closer to zero, The optical phase retardation film manufacturing method characterized by the above-mentioned. Coating a photocurable liquid crystal polymer layer on the substrate; Imprinting the photocurable liquid crystal polymer layer with a polymer mold having a recessed line pattern; Irradiating unpolarized ultraviolet light selectively using a mask to a region of the imprinted photocurable liquid crystal polymer layer; And applying heat such that the photocurable liquid crystal polymer layer having one region exposed to ultraviolet rays has a tempered temperature. In claim 13, And irradiating the non-polarized ultraviolet rays to the heated photocurable liquid crystal polymer layer as a whole. In claim 13, And said predetermined temperature is 180 degrees Celsius or more. In claim 13, The photocurable liquid crystal polymer layer is formed with a projection line pattern corresponding to the recessed line pattern of the polymer mold, The protruding line pattern corresponds to a region of the photocurable liquid crystal polymer layer selectively exposed to ultraviolet light using the mask and has a first protruding line pattern having anisotropy, and is not selectively exposed to ultraviolet light using the mask. A second projection line pattern corresponding to the other region of the photocurable liquid crystal polymer layer and having isotropy, And the first protrusion line pattern has a phase difference within a range of greater than 0 and less than or equal to λ / 2, and the second protrusion line pattern has a phase difference of zero. In claim 13, The coating is spin coating, The higher the speed of the coating, the closer the phase difference of the plurality of projection line patterns is to λ / 2, The higher the concentration of the photocurable liquid crystal polymer layer, the closer the phase values of the plurality of dolly line patterns are to zero. In claim 13, The method of manufacturing a photo-phase retardation film further comprising the step of silane treatment of the surface of the photocurable liquid crystal polymer layer. A first substrate, A second substrate facing the first substrate, A liquid crystal layer disposed between the first substrate and the second substrate and including a plurality of liquid crystal molecules; An optical phase retardation film disposed between at least one of the first substrate and the liquid crystal layer and between the second substrate and the liquid crystal layer, The photophase retardation film is made of a photocurable liquid crystal polymer and includes a plurality of protrusion line patterns having a phase difference within a range of 0 to λ / 2, And the plurality of protrusion line patterns have a liquid crystal alignment property to align liquid crystal molecules of the liquid crystal layer. The method of claim 19, The plurality of protrusion line patterns may have different length directions. The method of claim 20, The plurality of protrusion line patterns, A first projection line pattern having a longitudinal direction in a first direction, A second projection line pattern having a second direction different from the first direction in a longitudinal direction; The pier in the first direction and the second direction is 45 degrees. The method of claim 19, And the plurality of protruding line patterns have different phase differences. The method of claim 22, The plurality of protrusion line patterns, A first projection line pattern having anisotropy, And a second projection line pattern having an isotropy having a zero phase difference. The method according to any one of claims 19 to 23, And the long axis direction of the liquid crystal molecules is horizontally aligned so as to be substantially parallel to the longitudinal direction of the plurality of protrusion line patterns in an electric field member state. The method according to any one of claims 19 to 23, And the long axis direction of the liquid crystal molecules is vertically aligned so as to be substantially parallel to the rising direction of the plurality of protrusion line patterns in an electric field member state. The method of claim 25, And the surface of each of the plurality of protrusion line patterns is silane-treated.

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