CN103018803B - Brightness enhancement film and liquid crystal display device using same - Google Patents

Abstract

The invention provides a brightness enhancement film, which is used for modulating light. The brightness enhancement film includes a main body and a light modulation structure arranged on the main body, and the light modulation structure includes a self-assembled single-layer film. The invention also provides a liquid crystal display device using the brightness enhancing film. The invention has the advantages of being able to compensate light in a specific direction, producing a gradual light-gathering effect, and providing a liquid crystal display device with a wide viewing angle.

Description

Brightness enhancing film and liquid crystal display device using the brightness enhancing film

technical field

The invention relates to a brightness enhancement film and a liquid crystal display device using the brightness enhancement film.

Background technique

Liquid crystal displays control light transmittance through the rotation of liquid crystal molecules to display information. The most common TN type liquid crystal technology is the most mature and has the widest application range, but it has the disadvantage of small viewing angle. Due to the torsion characteristics of TN-type liquid crystals, when a voltage is applied to a general TN-type liquid crystal display, when the screen is viewed from the top of the screen, it is easy to see the long axis of the liquid crystal molecules, the light transmission is large, the screen will be too bright and white, and the contrast is low. ; When viewing the screen from the bottom of the screen, it is easy to see the short axis of the liquid crystal molecules, the light transmission is small, and the screen will be too dark, resulting in uneven light transmission and poor display effect. A common method is to paste a layer of optical compensation film on the outside of the screen panel, which can increase the viewing angle, but requires additional costs.

In order to improve the problem of insufficient viewing angle of TN-type liquid crystals, people began to make a fuss about the brightness enhancement film of the backlight assembly. Patent CN200410095781 discloses a backlight assembly of a liquid crystal display, wherein the brightness enhancement film is a prism sheet, including a plurality of light modulation structures, each of which is shaped into a scalene triangular prism, and each protrusion has a different shape from each other. and other bottom corners to adjust the viewing angle of the LCD monitor. However, the design of the scalene triangular prism will cause the amount of light transmission to be uncontrollable, and it is impossible to compensate for areas with poor viewing angles of TN-type liquid crystals, and its light guides only go in the same direction, which will cause uneven colors at other viewing angles, and at the same time make the The brightness-to-contrast ratio of the panel is greatly reduced, which is detected by the human eye. Patent CN200880000121 discloses a liquid crystal display backlight assembly, wherein the brightness enhancement film is a prism sheet, including a first prism surface and a second prism surface for incident light, the first prism surface is linear, and the second prism The surface is arc-shaped to adjust the viewing angle, but its light guide only goes in the same direction, which will cause uneven color at other viewing angles, and at the same time will greatly reduce the brightness and contrast ratio of the panel, which is detected by the human eye.

Contents of the invention

In view of this, it is necessary to provide a brightness enhancement film capable of realizing a wide viewing angle display effect and a liquid crystal display device using the brightness enhancement film.

A brightness enhancing film for modulating light. The brightness enhancement film includes a main body and a light modulation structure arranged on the main body, and the light modulation structure includes a self-assembled single-layer film.

A liquid crystal display device, comprising a liquid crystal display panel, a light control device, and a backlight module stacked in sequence, and the light control device includes the brightness enhancement film.

The invention has the advantages of providing a brightness-enhancing film, which can compensate light in a specific direction, can produce a gradual light-gathering effect, and provide a liquid crystal display device with a wide viewing angle.

Description of drawings

FIG. 1 is a schematic structural diagram of a liquid crystal display device provided by the present invention.

FIG. 2 is a schematic diagram of a liquid crystal display panel of the liquid crystal display device in FIG. 1 .

3 is a schematic diagram of the distribution of thiophenol SAMs molecules and naphthol SAMs molecules on the brightness enhancement film provided by Example 1 of the present invention.

Explanation of main component symbols

Liquid crystal display device 1 LCD panel 10 light control device 20 Backlight module 30 first side 14 second side 15 upper diffuser twenty one Brightness enhancement film twenty two lower diffuser twenty three Main body 222 light modulation structure 224 Thiophenol SAMs molecules 224a Naphthalenethiol SAMs molecules 224b

The following specific embodiments will further illustrate the present invention in conjunction with the accompanying drawings.

Detailed ways

Embodiment one:

As shown in FIG. 1 , a liquid crystal display device 1 according to an embodiment of the present invention includes a liquid crystal display panel 10 , a light control device 20 , and a backlight module 30 stacked sequentially from top to bottom. The light control device 20 includes a brightness enhancement film 22 and an upper diffusion sheet 21 and a lower diffusion sheet 23 respectively disposed on two sides of the brightness enhancement film 22 . It can be understood that the light control device 20 may also include other light control elements such as lenses and the like. The brightness enhancement film 22 includes a main body 222 and a light modulation structure 224 disposed on the main body 222 . The backlight module 30 provides a side light source to provide backlight for the liquid crystal display panel 10 .

The liquid crystal display panel 10 twists liquid crystal molecules by applying a voltage to control light transmittance to display images. As shown in FIG. 2 , the liquid crystal display panel 10 includes a first side 14 with high light transmittance and a second side 15 with low light transmittance. The light transmittance of the liquid crystal display panel 10 is determined by the first side 14 To said second side 15 it tapers off. In this embodiment, the first side 14 is the top end of the liquid crystal display panel 10 along the vertical direction, and the second side 15 is the bottom end of the liquid crystal display panel 10 along the vertical direction.

The light modulation structure 224 includes self-assembled monolayers (Self-assembled monolayers, SAMs) films. The SAMs film is formed by spraying SAMs molecules on the main body 222 by way of ink jet (Ink-Jet). The SAMs molecules can converge the light originally diverging in various directions within a certain angle range after passing through the light modulation structure 224 . Therefore, the light concentrating effect is more obvious at the position where the molecular density of SAMs is high, and the brightness of passing light is higher. In this embodiment, the SAMs molecules include thiophenol SAMs molecules 224a and naphthol SAMs molecules 224b. The lattice size of the thiophenol SAMs molecules 224a is 5*5 nanometers, and the lattice size of the naphthol SAMs molecules 224b is 2.5*2.5 nanometers. On the main body portion 222 per unit area, the arrangement density of the thiophenol SAMs molecules 224a with a larger crystal lattice is lower than the arrangement density of the naphthol SAMs molecules 224b. Therefore, on the main body portion 222 per unit area, the larger the ratio of the thiophenol SAMs molecules 224a to the naphthalenethiol SAMs molecules 224b, the smaller the density of the SAMs molecules in the light modulation structure 224, and the less light is extracted. .

As shown in FIG. 3 , the light modulation structure 224 on the main body portion 222 close to the first side 14 of the liquid crystal display panel 10 is pure thiophenol SAMs molecules 224a, and the thiophenol SAMs molecules 224a in the light modulation structure 224 and The ratio of naphthalenethiol SAMs molecules 224b gradually decreases from the first side 14 to the second side 15 so that the arrangement density of SAMs molecules of the light modulation structure 224 gradually increases from the first side 14 to the second side 15 .

Therefore, the part of the light modulation structure 224 on the brightness enhancement film 22 with a lower density is arranged corresponding to the first side 14 of the liquid crystal display panel 10 with a higher light transmittance, and the part of the brightness enhancement film 22 with a higher density of the light modulation structure 224 Part of it is set corresponding to the second side 15 with a lower light transmittance of the liquid crystal display panel 10, which can compensate the phenomenon of uneven brightness from different viewing angles caused by the different light transmittance of different parts of the liquid crystal display panel 10, so as to achieve wide The effect of perspective.

In other embodiments, the SAMs molecules include but are not limited to ethanedithiol SAMs molecules with a lattice size of 8*8nm or 4*4nm, m-fluorophenol SAMs molecules with a lattice size of 5*5nm, and The combination of p-nitrophenol SAMs molecules with a lattice size of 10*10 nm or 6*6 nm, and the light modulation structure 224 can also be formed by mixing the above-mentioned various SAMs molecules. As long as the arrangement density of SAMs molecules gradually increases from the first side 14 with higher light transmittance to the second side 15 with lower light transmittance, all implementations are within the protection scope of the present invention.

Those of ordinary skill in the art should recognize that the above embodiments are only used to illustrate the present invention, rather than to limit the present invention. Alterations and variations are within the scope of the claimed invention.

Claims (7)

1. A brightness-enhancing film, which is used to modulate light, the brightness-enhancing film comprising a main body and a light modulation structure arranged on the main body, the light modulation structure comprising a self-assembled monolayer film, The arrangement density of the molecules of the self-assembled monolayer gradually increases from one side of the main body to the opposite side. 2. The brightness enhancing film according to claim 1, wherein the self-assembled monolayer film comprises multiple self-assembled monolayer film molecules. 3. The brightness enhancing film as claimed in claim 2, characterized in that: the self-assembled monolayer film molecules are composed of thiophenol molecules, naphthalenethiol molecules, ethanedithiol molecules, and m-fluorophenol molecules. , p-nitrophenol molecules at least two of them combined. 4. The brightness enhancing film according to claim 1, wherein the self-assembled single-layer film is disposed on the surface of the main body by ink jetting. 5. A liquid crystal display device, comprising a liquid crystal display panel stacked in sequence, a light control device, and a backlight module, said light control device comprising the brightening device according to any one of claims 1-4 film, the light emitted by the backlight module is modulated by the brightness enhancement film and then enters the liquid crystal display panel. The liquid crystal display panel includes a first side with high light transmittance and a second side with low light transmittance. The liquid crystal display The light transmittance of the panel gradually decreases from the first side to the second side, and the arrangement density of self-assembled monolayer film molecules on the brightness enhancement film gradually increases from the first side to the second side . 6. The liquid crystal display device according to claim 5, wherein the first side is the top end of the liquid crystal display panel along the vertical direction, and the second side is the bottom end of the liquid crystal display panel along the vertical direction. 7. The liquid crystal display device according to claim 5, wherein the light control device further comprises an upper diffusion sheet and a lower diffusion sheet respectively disposed on two sides of the brightness enhancement film.