KR101217160B1 - Liquid Crystal Display Device using a microprism - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device using a micro prism, and in particular, a first substrate, a second substrate which is spaced apart from the first substrate, and includes a red, green, and blue sub color filter, and the first and A liquid crystal layer interposed between the second substrate, first and second polarizing plates respectively disposed below and above the first substrate and the second substrate;

A backlight unit disposed below the first polarizing plate and spaced apart from the first polarizing plate, and disposed between the first polarizing plate and the backlight unit, and when light passes, red light, green light, and blue light are emitted at an interval, and the red sub color filter and green It characterized in that it comprises a micro-prism film formed to reach the light of the same color component to each of the sub color filter and the blue sub color filter.

Description

Liquid crystal display device using a microprism

1 is a cross-sectional view showing a conventional liquid crystal display device.

2 is a cross-sectional view showing a case where a voltage is applied to a conventional liquid crystal display device.

3A illustrates the principle of a prism.

3b illustrates the principle of a microprism;

4 is a cross-sectional view showing a liquid crystal display device according to a first embodiment of the present invention.

5A to 5C are cross-sectional views showing schematic shapes of microprism films.

6 is a cross-sectional view illustrating a case where a voltage is applied to the liquid crystal display according to the first embodiment of the present invention.

7 is a cross-sectional view illustrating a case where a voltage is applied to the liquid crystal display according to the second embodiment of the present invention.

8 is a cross-sectional view illustrating a case where a voltage is applied to the liquid crystal display according to the third exemplary embodiment of the present invention.

Description of the Related Art [0002]

210: first substrate 220: second substrate

230: liquid crystal layer 250: liquid crystal panel

260 microprism films 265 and 266 first and second polarizing plates

270: backlight unit 275: fluorescent lamp

280: liquid crystal display 290: white incident light

220a, 220b, 220c: Red, Green, Blue Sub Color Filter

R, G, B: Red, Green, Blue Light

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display, and in particular, white light incident from a backlight is incident to each of the red, green, and blue sub color filters separately by using a microprism function, thereby minimizing light loss. By improving the brightness of the device, it is characterized by reducing the power consumption.

In general, a cathode ray tube (CRT) has been most used among image display apparatuses displaying image information on a screen, but this has been accompanied with a lot of inconveniences because it is bulky and heavy compared to the display area.

In response to this, even when the display area is large, the thickness of the thin film type flat panel display device which can be easily used in any place has been developed, and it is gradually replacing the CRT display device.

In particular, a liquid crystal display device (LCD) has excellent display resolution than other flat panel display devices, and exhibits a fast response speed as compared with CRTs when a moving image is realized.

As is known, the driving principle of the liquid crystal display device utilizes the optical anisotropy and polarization properties of the liquid crystal.

Since the liquid crystal is thin and long in structure, the direction of the molecular arrangement can be controlled by artificially applying an electromagnetic field to the liquid crystal molecules having directionality and polarization in the molecular arrangement.

Therefore, if the alignment direction is arbitrarily adjusted, light may be transmitted or blocked according to the alignment direction of the liquid crystal molecules by optical anisotropy of the liquid crystal, thereby displaying colors and images.

In addition, the active matrix liquid crystal display device adds an active element to each pixel arranged in a matrix form, and controls the operation of each pixel by using the switching characteristics of the element, and implements a memory function through the electro-optical effect of the liquid crystal. It is.

In general, a liquid crystal display device is a passive display device having no own light source and requires a backlight assembly such as a lamp, a light guide plate, and sheets, which plays an important role in the display performance of the liquid crystal display device.

Hereinafter, a conventional liquid crystal display device will be described with reference to the accompanying drawings.

1 is a schematic cross-sectional view of a conventional liquid crystal display.

As illustrated, a liquid crystal including first and second substrates 10 and 20 spaced apart from each other and disposed to face each other, and a liquid crystal layer 30 interposed between the first and second substrates 10 and 20. The liquid crystal display device 80 includes a panel 50 and a backlight unit 70 disposed on a rear surface of the liquid crystal panel 50.

First and second transparent electrodes 15 and 25 are formed on inner surfaces of the first and second substrates 10 and 20, respectively, and thus an electric field formed between the first and second transparent electrodes 15 and 25 when voltage is applied. By the arrangement of the above-described liquid crystal layer 30, the liquid crystal layer 30 is composed of liquid crystal molecules having birefringence characteristics according to the birefringence characteristics of the liquid crystal molecules, the light supplied from the backlight unit 70 described above It can be implemented as desired screen.

Although not shown in detail in the drawings, a switching device (not shown) is formed on the first substrate 10 to turn on / off a voltage in subpixel units, which is a minimum unit for implementing a screen, and is connected to the switching device. The first electrode 15 serves as a pixel electrode, and the light supplied from the backlight unit 70 is incident on the second substrate 20 through each of the red, green, and blue sub color filters (not shown). The screen is implemented, and the second transparent electrode 25 formed on the lower front surface of the second substrate 20 serves as a common electrode to which a common voltage is applied.

2 is a cross-sectional view illustrating a case where a voltage is applied to a conventional liquid crystal display, and will be described in detail with reference to this.

As shown, a fluorescent lamp 75 provided in the backlight unit 70, and a prism sheet 60 for collecting light incident from the upper portion spaced apart from the backlight unit 70, The first polarizing plate 65 is configured above the prism sheet 60.

An array substrate, which is a first substrate 10, is formed above the first polarizing plate 65, and a color filter substrate, which is a second substrate 20, is formed above the first substrate 10. In the state where the liquid crystal layer 30 is interposed between the first substrate 10 and the second substrate 20, the second polarizing plate 66 is formed on the second substrate 20.

In addition, a black matrix 82 for blocking a non-image area is formed in the second substrate 20 in a section between each of the red, green, and blue sub color filters 20a, 20b, and 20c.

When a voltage is applied to the liquid crystal display device 80, the white light 90 incident from the backlight unit 70 is first collected on the prism sheet 60 in a state where the white light 90 is collected in the center by the prism sheet 60. It passes through the polarizing plate 65.

Here, the first and second polarizers 65 and 66 have a characteristic of selectively passing almost all polarized light but reflecting almost all other polarized light among vertical polarization and horizontal polarization. Obtained from the material.

Subsequently, the light transmitted through the first polarizing plate 65 passes through the first substrate 10 and is incident to each of the red, green, and blue sub color filters 20a, 20b, and 20c to display a desired image.

However, the light passing through the prism sheet 60 is incident on each of the sub color filters 20a, 20b, and 20c collectively without being distinguished from each of the red, green, and blue sub color filters 20a, 20b, and 20c. Done.

As described above, the conventional liquid crystal display device includes a liquid crystal panel 50, a circuit unit (not shown), and a backlight 70, which are three components, among which the backlight 70 serves as a light source. The liquid crystal panel 50 serves to display an image by receiving a signal, and the circuit unit mainly makes a signal suitable for the liquid crystal panel 50 by matching a timing signal of an input signal or through signal processing.

However, in terms of the light efficiency of the liquid crystal display device, only about 5% of the first light incident from the backlight 70 is output, and about 95% of the liquid crystal panel 50 is lost.

In detail, when the light incident from the backlight 70 is 100, about 55% is lost in the polarizing plates 65 and 66, and about 50% is also lost in terms of the aperture ratio.

In addition, about 75% is lost in the color filter substrate, which is the second substrate 20, and finally only about 5% of the original amount of light is transmitted.

Accordingly, various methods for compensating for such loss have been conventionally devised, and in the most general method, the above-described prism sheet is incorporated into the backlight to concentrate light in the center, thereby improving the luminance at the center, and also polarizing plate. It is also possible to combine the technology to recover the light lost in the system, improving the brightness by about 35%.

However, in the conventional liquid crystal display, the backlight generates white light as a light source, and the white light is incident on the red, green, and blue sub color filters collectively. The light is absorbed by the color filter film, which causes a problem that light loss occurs as a whole.

Accordingly, the present invention has been made for the purpose of solving the above-mentioned problems, in particular, the liquid crystal display device according to the present invention by applying a micro-prism function to separate the white light incident from the backlight into red, green, blue light, this separation The light having the same color component is incident on each of the sub color filters, thereby minimizing light loss, thereby improving luminance, and thus reducing power consumption.

According to an exemplary embodiment, a liquid crystal display device includes a first substrate, a second substrate spaced apart from the first substrate, and including a red, green, and blue sub color filter, and the first and second substrates. A liquid crystal layer interposed therebetween;

First and second polarizing plates respectively disposed below and above the first substrate and the second substrate, and a backlight unit configured below the first polarizing plate and spaced apart from the first polarizing plate;

When the light passes, red light, green light, and blue light are emitted at intervals, and the red sub color filter, the green sub color filter, and the blue sub color filter each have the same color component. And a micro prism film formed to reach light.

Here, the backlight unit includes a fluorescent lamp for generating white light.

In addition, the micro-prism film is characterized in that produced by the injection or extrusion method.

In another embodiment, a liquid crystal display device includes a first substrate, a second substrate spaced apart from the first substrate, and including a red, green, and blue sub color filter, and the first and second substrates. A liquid crystal layer interposed therebetween;

It is integrally formed under the first substrate, and when light passes, red light, green light, and blue light are emitted at intervals, and light having the same color component reaches each of the red sub color filter, the green sub color filter, and the blue sub color filter. A micro-prism film formed to be;

And a first polarizing plate formed below the micro prism film and a second polarizing plate formed above the second substrate, and a backlight unit spaced apart from the first polarizing plate.

In another embodiment, a liquid crystal display device includes a first substrate, a second substrate spaced apart from the first substrate, and including a red, green, and blue sub color filters therein; A liquid crystal layer interposed between the second substrates;

Located between the liquid crystal layer and the first substrate, and integrally formed with the first substrate, when the light passes, the red light, the green light and the blue light are emitted at intervals, the red sub color filter and the green sub color filter; A micro prism film formed such that light having the same color component reaches each of the blue sub color filters;

And a backlight unit configured to be spaced apart from the first polarizer, and a first polarizer configured to be disposed below the first substrate, and a second polarizer configured to be disposed above the second substrate.

In this case, the method may further include configuring a buffer layer on the micro-prism film.

Hereinafter, a liquid crystal display device according to the present invention will be described with reference to the accompanying drawings.

3A shows the principle of a general prism.

As shown in the figure, when the white incident light 110 is incident on the prism 120, since each wavelength has a principle of emitting different light to different positions, red light (R) and green light (G) according to each wavelength. It is separated by blue light (B) and emitted.

3B is a diagram showing the principle of the micro-prism.

As illustrated, when the white incident light 110 passes through the micro-prism 130, the white incident light 110 emits light at a predetermined interval from the red light R having a long wavelength to the green light G and the blue light B.

Accordingly, by applying a method of manufacturing a pixel-sized micro-prism film using the micro-prism principle, the micro-prism film may be separately manufactured and assembled, or the micro-prism film may be directly manufactured in the lower part or inside of the panel. Do.

--- First Embodiment ---

Hereinafter, a liquid crystal display according to the present invention will be described in detail with reference to the accompanying drawings.

4 is a cross-sectional view showing a first embodiment of a liquid crystal display device according to the present invention.

As illustrated, a liquid crystal including first and second substrates 210 and 220 spaced apart from each other and disposed to face each other, and a liquid crystal layer 230 interposed between the first and second substrates 210 and 220. The liquid crystal display 280 includes the panel 250 and the backlight unit 270 disposed on the rear surface of the liquid crystal panel 250.

The liquid crystal panel 250 includes an array substrate as the first substrate 210, a color filter substrate as the second substrate 220, and a liquid crystal layer 230 interposed therebetween.

Here, a TFT switching element (not shown) is formed in the first substrate 210, and red, green, and blue sub color filters 220a, 220b, and 220c are formed in the second substrate 220. The black matrix 282 which blocks a non-picture area is comprised in each interval.

In addition, first and second transparent electrodes (not shown) are formed on inner surfaces of the first and second substrates 210 and 220, respectively, and the liquid crystal layer is formed by an electric field formed between the first and second transparent electrodes when voltage is applied. An array 230 is formed, and the liquid crystal layer 230 is formed of liquid crystal molecules having birefringence characteristics, and according to the birefringence characteristics of the liquid crystal molecules, the light supplied from the backlight unit 270 described above may be implemented as a desired screen. Will be.

Here, a first polarizer 265 is attached below the first substrate 210, and a second polarizer 266 is attached above the second substrate 220.

In addition, the first substrate 210 to which the first polarizing plate 265 is attached is spaced apart from the first substrate 210, and the backlight unit 270 is formed on the rear surface of the first substrate 210. The micro prism film 260 is comprised between spaced apart.

As described above, a switching element for turning on / off a voltage is formed on the first substrate 210 in units of a sub pixel, which is a minimum unit for implementing a screen, and a first electrode (not shown) connected to the switching element is It serves as a pixel electrode.

In addition, the light supplied from the backlight unit 270 described above is incident on the second substrate 220 by being separated into each of the red, green, and blue sub color filters 220a, 220b, and 220c to implement a screen. The second transparent electrode (not shown) formed on the entire surface of the second substrate 220 serves as a common electrode to which a common voltage is applied.

In this case, when the micro-prism film 260 is manufactured and embedded separately, first, the micro-prism film 260 having a fine prism shape is manufactured through an injection or extrusion method, and the pattern shape of the micro-prism film 260 is the first polarizing plate 265. And the backlight unit 270 are spaced apart from each other.

5A to 5C are cross-sectional views schematically illustrating the shape of the micro-prism film, which will be described with reference to the drawings.

As shown in FIGS. 5A to 5C, the micro-prism film 260 has a triangular shape 292, a fan shape 294, and a semicircle shape 296 and has a configuration repeatedly arranged in one direction.

In detail, the micro-prism film 260 defines a top point according to each shape 292, 294, and 296 as each vertex 295a, 295b, and 295c. The distance connecting the becomes a repetition distance (d), each shape 292, 294, 296 has a plurality of repetition distance (d) is arranged regularly in one direction.

In this case, the repetition distance (d) may be the same or different, which may be variously changed according to the resolution and dimensions.

6 is a diagram illustrating a case where a voltage is applied to the liquid crystal display according to the first embodiment of the present invention.

As illustrated, a liquid crystal including first and second substrates 210 and 220 spaced apart from each other and disposed to face each other, and a liquid crystal layer 230 interposed between the first and second substrates 210 and 220. The liquid crystal display 280 includes the panel 250 and the backlight unit 270 disposed on the rear surface of the liquid crystal panel 250.

When the power is applied to the liquid crystal display 280, white light 290 is irradiated from the fluorescent lamp 275 provided in the backlight unit 270, and the white light 290 is a micro-prism film 260. The light penetrates the liquid crystal panel 250 and passes through the liquid crystal panel 250.

Here, in the above-described conventional liquid crystal display device, only the light is collected at the center by the prism sheet, but in the present embodiment, the white light 290 incident from the backlight unit 270 passes through the micro prism film 260. In response to each of the red, green, and blue sub-color filters 220a, 220b, and 220c, light is separated into light having the same color component and is incident.

In detail, the light passing through the aforementioned micro-prism 130 (FIG. 3B) is emitted from the red light (R) having a long wavelength, green light (G), and blue light (B) in sequence at a predetermined interval. Since the white light 290 incident from the backlight unit 270 passes through the micro-prism film 260 having the respective shapes (292, 294, and 296 in FIGS. 5A to 5C), the red light is emitted. Only the red light R is incident on the sub color filter 220a, only the green light G is incident on the green sub color filter 220b, and only the blue light B is incident on the blue sub color filter 220c, thereby minimizing light loss. You can do it.

In this case, in general, a stripe type in which the red, green, and blue sub color filters 220a, 220b, and 220c are repeatedly arranged is mainly used. Thus, each sub having the same color component in one direction is used. Since the color filters 220a, 220b, and 220c are arranged, color mixing of light can be prevented.

Therefore, in the present invention, the light loss can be minimized by allowing only the light having the same color component to each of the sub color filters into each of the red, green, and blue sub color filters using the micro prism film. It is possible to reduce the power.

In addition, when the micro prism film 260 is manufactured separately, the micro prism film 260 manufactured separately is laminated between the first polarizing plate 265 and the backlight unit 270 for more stable color separation. It can be composed of a multilayer which is one form.

--- Second Embodiment ---

Hereinafter, a liquid crystal display according to a second exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

The second embodiment of the present invention is a modification of the first embodiment and briefly describes only the core contents.

7 is a cross-sectional view showing a second embodiment of a liquid crystal display device according to the present invention.

As shown, the first and second substrates 310 and 320 are spaced apart from each other and disposed to face each other, and the first and second substrates 310 and 320 and the liquid crystal layer 330 interposed therebetween. The liquid crystal display device 380 includes a liquid crystal panel 350 and a backlight unit 370 disposed on the rear surface of the liquid crystal panel 350.

Here, the micro prism film 360 is integrally formed under the first substrate 310, and the first polarizing plate 365 is attached to the micro prism film 360 under the second substrate 320. The second polarizing plate 366 is attached to the upper side.

Accordingly, when power is applied to the liquid crystal display, the red, green, and blue light (R, G, B) having the same color component corresponding to each of the sub color filters 320a, 320b, and 320c is applied as in the first embodiment. It is incident separately.

Here, in the first embodiment, the first polarizing plate 365 is positioned above the micro prism film 360, but in the second embodiment, the micro prism film 360 is integrally formed under the first substrate 310. As a result, the first polarizing plate 365 is characterized in that it is configured.

--- Example 3 ---

The third embodiment of the present invention is a modification of the first embodiment and briefly describes only the core contents.

8 is a cross-sectional view showing a third embodiment of a liquid crystal display device according to the present invention.

As shown, the first and second substrates 410 and 420 spaced apart from each other and disposed to face each other, and the first and second substrates 410 and 420 and the liquid crystal layer 430 interposed therebetween. The liquid crystal display device 480 includes a liquid crystal panel 450 and a backlight unit 470 disposed on the rear surface of the liquid crystal panel 450.

Here, before the TFT array wiring (not shown) is formed on the first substrate 410, the micro prism film 460 is integrally formed, and a buffer for protecting it on the micro prism film 460. After the film (not shown) is formed, a TFT array wiring (not shown) is formed on the buffer film.

In addition, a first polarizer 465 is attached to a lower portion of the first substrate 410, and a second polarizer 466 is attached to an upper portion of the second substrate 420.

Therefore, when power is applied to the liquid crystal display, the red, green, and blue light having the same color component (R, G, The incident is separated into B).

Here, in the second embodiment, the micro-prism film 460 is integrally formed under the first substrate 410. In the third embodiment, the micro-prism film 460 is disposed on the first substrate 410. Before the TFT array wiring (not shown) is formed, it is characterized by being integrally formed.

Accordingly, in the second and third embodiments according to the present invention, the same function as the first embodiment is achieved, and additional material costs are reduced by integrally forming the micro-prism film on the lower or upper surface of the first substrate. Has the advantage of saving.

In the liquid crystal display according to the present invention, the light separated by each color component is incident to each of the red, green, and blue sub-color filters by using the micro-prism function, thereby minimizing light loss, thereby reducing power consumption. There is an effect that can be reduced.

Claims (6)

delete delete delete delete A first substrate; A second substrate spaced apart from the first substrate and including a red, green, and blue sub color filters therein; A liquid crystal layer interposed between the first and second substrates; Located between the liquid crystal layer and the first substrate, and integrally formed with the first substrate, when light passes, red light, green light, and blue light are emitted at intervals, and the red sub color filter, the green sub color filter, and the blue light are separated from each other. A micro prism film formed so that light of the same color component reaches each of the sub color filters; A first polarizing plate formed under the first substrate and a second polarizing plate formed over the second substrate; A backlight unit configured to be spaced apart from the first polarizing plate Liquid crystal display comprising a. 6. The method of claim 5, And forming a buffer film on the micro-prism film.

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