KR20070050536A - Optical sheet and liquid crystal display having the same - Google Patents

Abstract

The present invention relates to an optical sheet capable of preventing the flow of the optical sheet by assembling the ear parts of the optical sheet and a liquid crystal display having the same.

The present invention provides an optical sheet and a liquid crystal display having the optical sheet ear portion of at least one optical sheet of at least one of the at least one optical sheet having the optical sheet ear portion protruding from at least one side. It is about.

Optical sheet, ear, assembly, mold frame, double sided tape

Description

Optical sheet and liquid crystal display having the same {OPTICAL SHEET AND LIQUID CRYSTAL DISPLAY HAVING THE SAME}

1 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

2 is a plan view showing an LED flexible substrate according to an embodiment of the present invention.

3 is a cross-sectional view taken along line III-III 'of FIG.

4 is a plan view illustrating a light guide plate according to an exemplary embodiment of the present invention.

5 is a plan view showing a first diffusion sheet ear portion.

6 is a plan view showing a second diffusion sheet ear portion.

7 is a perspective view showing assembly of the first and second diffusion sheet ears.

FIG. 8 is a cross-sectional view of a double-sided tape attached on the first diffusion sheet ear portion after the first and second diffusion sheet ear portions are assembled.

9 is a rear view of the mold frame according to the embodiment of the present invention.

10 is a front view of a mold frame according to an embodiment of the present invention.

<Code Description of Main Parts of Drawing>

10 liquid crystal display device 20 top chassis

30: liquid crystal display panel 60: driving circuit

70: flexible printed circuit board 100: backlight unit

110: light source unit 120: LED

150: LED flexible substrate 180: light guide plate

190: Light guide panel 200: Reflective sheet

210: optical sheet 220: first diffusion sheet

230: first diffusion sheet ear 240: second diffusion sheet

250: second diffusion sheet ear 260: mold frame

270: light guide plate seating portion 280: reflective sheet seating portion

290: Optical sheet ear seating portion 300: Light source unit seating portion

The present invention relates to an optical sheet and a liquid crystal display device having the same, and more particularly, to an optical sheet and a liquid crystal display device having the same, by assembling the ear parts of the optical sheet.

As information technology advances, the market for computers and televisions as well as personal mobile communication devices such as mobile phones is increasing. The display device, which is the final connection medium between these devices and the user, is required to have high quality, and thus, a liquid crystal display device, which is not a conventional CRT (Cathode Ray Tube), has been in the spotlight recently.

A liquid crystal display device is a device that displays an image using liquid crystal. The liquid crystal display includes a liquid crystal display panel displaying an image, a backlight unit providing light to the liquid crystal display panel, and a mold frame fixing the same.

The liquid crystal display panel includes a thin film transistor substrate and a color filter substrate bonded together with a liquid crystal interposed therebetween.

The backlight unit includes a light source unit for providing light, a light guide plate for guiding light emitted from the light source unit, a reflection sheet positioned under the light guide plate to reflect light emitted from the lower part of the light guide plate in the direction of the light guide plate, and a liquid crystal display panel positioned above the light guide plate. An optical sheet for uniformly dispersing and condensing light in the furnace is included. By the way, generally, the optical sheet which consists of two or more sheets is provided with the optical sheet ear part protruding with respect to them. The optical sheet ear portion is seated and fixed to the optical sheet ear seat portion formed in the mold frame corresponding to the optical sheet ear portion. However, since the optical sheet ear seat portion of the mold frame is formed somewhat larger than the optical sheet ear portion, the optical sheet may flow. In addition, since each optical sheet is simply laminated and assembled, each optical sheet is easily flowed. If each optical sheet flows without being fixed on the mold frame, the optical sheet is scratched. As a result, foreign matter defects, white spot defects, stains, and the like may occur, and display quality of the LCD may be degraded.

The technical problem to be achieved by the present invention is to provide an optical sheet and a liquid crystal display having the same that can prevent the flow of the optical sheet by assembling the ears of the optical sheet.

The present invention provides an optical sheet, characterized in that the optical sheet ear portion of at least one optical sheet of at least one optical sheet having an optical sheet ear portion protruding from at least one side is partially removed.

The groove is formed in the ear of the optical sheet of the optical sheet which is located at the lowest layer of the at least two optical sheets.

Specifically, the optical sheet ear portion of the optical sheet located on the lowermost layer is characterized in that it is assembled so as to be located above the optical sheet ear portion of the optical sheet located on the top layer of the at least two optical sheets.

On the other hand, the at least two optical sheets are characterized in that it comprises two diffusion sheets to scatter the light evenly.

The at least two optical sheets may include one diffusion sheet which scatters light and spreads the light evenly; And at least one prism sheet for increasing the luminance by refracting and condensing the light.

In detail, the at least two optical sheets may further include one luminance improving sheet for improving luminance.

The present invention provides a liquid crystal display panel for displaying an image; A light source unit providing light to the liquid crystal display panel; A light guide plate for guiding light from the light source unit to the liquid crystal display panel; The optical sheet ear portion of at least one optical sheet of the at least one optical sheet having an optical sheet ear portion formed on the light guide plate and protruding from at least one side thereof is provided with a groove formed by removing a portion of the optical sheet ear portion. do.

The groove is formed in the ear of the optical sheet of the optical sheet which is located at the lowest layer of the at least two optical sheets.

Specifically, the optical sheet ear portion of the optical sheet located on the lowermost layer is characterized in that it is assembled so as to be located above the optical sheet ear portion of the optical sheet located on the top layer of the at least two optical sheets.

On the other hand, the at least two optical sheets are characterized in that it comprises two diffusion sheets to scatter the light evenly.

The at least two optical sheets may include one diffusion sheet which scatters light and spreads the light evenly; And at least one prism sheet for increasing the luminance by refracting and condensing the light.

In detail, the at least two optical sheets may further include one luminance improving sheet for improving luminance.

Other features of the present invention will become apparent from the description of the embodiments with reference to the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the liquid crystal display device 10 according to an exemplary embodiment of the present invention includes a liquid crystal display panel 30 for displaying an image, a driving circuit 60 for driving the liquid crystal display panel 30, and a driving circuit 60. ), A flexible printed circuit board 70 for driving light, a backlight unit 100 for providing light to the liquid crystal display panel 30, a fixing of the backlight unit 100, and a mold frame 260 for mounting the liquid crystal display panel 30. ) Is included.

The liquid crystal display panel 30 includes a liquid crystal for controlling light transmittance, a thin film transistor substrate 40 and a color filter substrate 50 bonded together with a liquid crystal interposed therebetween.

The liquid crystal is rotated by the difference between the pixel voltage from the pixel electrode of the thin film transistor substrate 40 and the common voltage from the common electrode of the color filter substrate 50 to adjust the light transmittance. To this end, the liquid crystal is made of a material having dielectric anisotropy and refractive index anisotropy.

The thin film transistor substrate 40 includes a thin film transistor and a pixel electrode formed in a pixel region defined by the intersection of data lines and gate lines on a substrate such as glass.

The thin film transistor transfers the image signal supplied from the data line to the pixel electrode in response to the scan signal supplied from the gate line. The pixel electrode applies a pixel voltage to the liquid crystal using the image signal charged therein. To this end, the pixel electrode is formed of a transparent conductive metal such as indium tin oxide (ITO) or indium zinc oxide (IZO).

The color filter substrate 50 includes a black matrix formed in a matrix on a substrate such as glass, a red, green, blue color filter formed in a region partitioned by the black matrix, and a common electrode for applying a common voltage to the liquid crystal. .

The black matrix is formed of black metal or organic material that can block light in order to block external light and prevent light leakage current of the thin film transistor. The red, green, and blue color filters each contain red, green, and blue pigments that transmit or absorb light of a specific wavelength, and realize color through additive mixing of red, green, and blue light. The common electrode applies a common voltage to the liquid crystal. To this end, the common electrode is formed of a transparent conductive metal such as ITO or IZO.

The driving circuit 60 is mounted on a thin film transistor substrate 40 by a chip on glass (COG) method and includes a gate driving circuit supplying a scan signal to a gate line and data supplying an image signal to a data line. It consists of a driving circuit. Here, the gate driving circuit may be directly formed on the thin film transistor substrate 40.

The flexible printed circuit board 70 is connected to the thin film transistor substrate 40 through the anisotropic conductive film. In the flexible printed circuit board 70, a plurality of electronic devices 80 generating power signals, data signals, various control signals, etc. are mounted in a soldering manner to drive the driving circuit 60. Power signals, data signals and various control signals generated by the plurality of electronic devices 80 are supplied to the driving circuit 60 through the driving signal line 90.

The backlight unit 100 is a light source unit 110 that provides light, a light guide plate 180 for guiding light emitted from the light source unit 110, and a light emitted from the light guide plate 180 under the light guide plate 180. The reflective sheet 200 reflects the light toward the light guide plate 180, and the optical sheet 210 positioned above the light guide plate 180 to uniformly disperse the light to the liquid crystal display panel 30 and to condense the light.

As shown in FIGS. 2 and 3, the light source unit 110 includes an LED 120 for emitting light and an LED flexible substrate 150 for fixing the LED 120.

The LED 120 has a package body 140 having a cup-shaped cavity 130 for accommodating the LED chip 122 therein and is attached to the LED flexible substrate 150 by soldering. The LED chip 122 receives light from the LED driving signal line 160 to generate light.

The LED 120 is attached to the back of the LED flexible substrate 150 by a soldering method. In order to apply driving power to the LED 120, a plurality of LED driving signal lines 160 are formed in the LED flexible substrate 150. One side of the plurality of LED driving signal lines 160 is connected to the positive electrode pad 152, the first and second negative electrode pads 154 and 156, respectively. Here, the LED driving signal lines 160 connected to the anode pads 152 of the plurality of LED driving signal lines 160 are connected to the anodes of all of the LEDs 120, and the first and the plurality of LED driving signal lines 160 are connected to the anodes of the LED driving signal lines 160. Each of the LED driving signal lines 160 connected to the second cathode pads 154 and 156 is connected to the cathodes of the respective LEDs 120.

In addition, an adhesive member 170 is attached to the rear surface of the LED flexible substrate 150 to bond the LED flexible substrate 150 to the mold frame 260 and the light guide plate 180. That is, the LED flexible substrate 150 is seated on the light source unit seating portion of the mold frame 260 and then bonded to the mold frame 260 by the adhesive member 170 and to the light guide plate 180.

The light guide plate 180 is seated on the rear surface of the mold frame 260 to guide the light emitted from the LED 120 to the liquid crystal display panel 30. In order to seat the light guide plate 180 on the back surface of the mold frame 260, the light guide plate 190 protruding from the light guide plate 180 is formed at a predetermined position of the edge of the light guide plate 180.

The reflective sheet 200 is mounted on the rear surface of the mold frame 260 to reflect the light emitted from the lower portion of the light guide plate 180 toward the light guide plate 180. To this end, the reflective sheet 200 is coated with a material having a high reflectance on the base material. That is, Ag, Ti, etc. are mainly coated as a reflective member on a base material such as SUS (Steel Use Stainless), brass, aluminum, and PET (Polyethylene Terephthalate).

The optical sheet 210 is disposed above the light guide plate 180 to uniformly disperse the light to the liquid crystal display panel 30 and to condense it. The optical sheet 210 is a diffusion sheet that scatters the light emitted from the light guide plate 180 to spread it evenly, a prism sheet that increases the brightness by refracting and condensing the light emitted from the diffusion sheet, and easy to generate scratches. It is generally composed of two or more protection sheet to protect the prism sheet that can appear and to spread the light to widen the viewing angle narrowed by the prism sheet, and to improve the brightness of the sheet. . If the optical sheet 210 is composed of two sheets, it is generally composed of two sheets of diffusion sheets or one sheet of diffusion and one sheet of prism. And, if the optical sheet 210 is composed of three sheets it is generally composed of one sheet and two prism sheets. In addition, if the optical sheet 210 is composed of four sheets, it is generally composed of one diffuser sheet, two prism sheets, and one luminance enhancer sheet. However, hereinafter, it will be described on the assumption that it is composed of two optical sheets 210, that is, the first and second diffusion sheets 220 and 240, as shown in FIG.

As described above, each of the first and second diffusion sheets 220 and 240 scatters the light emitted from the light guide plate 180 to evenly spread the light. Each of the first and second diffusion sheets 220 and 240 is provided with first and second diffusion sheet ear portions 230 and 250 protruding therefrom, as shown in FIGS. 5 and 6. A groove is formed in the first diffusion sheet ear portion 230 protruding from the first diffusion sheet 220 positioned at the lowermost layer. In addition, the first diffusion sheet ear portion 230 is formed perpendicular to the second diffusion sheet ear portion 250. Due to this structure, the first and second diffusion sheets 220 and 240 may be assembled. In other words, as shown in FIG. 7, the first diffusion sheet ear portion 230 protruding from the first diffusion sheet 220 positioned at the lowermost layer is formed to protrude from the second diffusion sheet 240 positioned at the uppermost layer. The first and second diffusion sheet ear portions 230 and 250 may be assembled to be positioned on the second diffusion sheet ear portion 250 such that the first diffusion sheet ear portion 230 intersects with the second diffusion sheet ear portion 250. For this reason, the first and second diffusion sheets 220 and 240 are coupled to each other to prevent flow.

Meanwhile, even when the first and second diffusion sheet ears 230 and 250 are assembled, the first and second diffusion sheets 220 and 240 may flow. For this reason, as shown in FIG. 8, the double-sided tape 320 may be attached onto the first diffusion sheet ear portion 230 to completely prevent the flow of the first and second diffusion sheets 220 and 240. However, if the double-sided tape 320 is attached while the first and second diffusion sheet ears 230 and 250 are not assembled, the first diffusion sheet ear 230 disposed at the lowermost layer may not be attached to the double-sided tape 320. Most likely not. That is, if the first and second diffusion sheets 220 and 240 are simply stacked, the double-sided tape 320 is likely to be adhered only to the second diffusion sheet ear portion 250 in the uppermost layer and is not adhered to the double-sided tape 320. The first diffusion sheet 220 may not be easily flowed.

However, after assembling the first and second diffusion sheet ears 230 and 250 as in the embodiment of the present invention, if the double-sided tape 320 is attached to the first diffusion sheet ear 230, the first and second diffusion sheets 320 are attached. The flow of the diffusion sheets 220 and 240 may be completely blocked. On the other hand, the double-sided tape 320 is attached to the first diffusion sheet ear portion 220 and attached along the four sides of the outer portion of the second diffusion sheet 240. The double-sided tape 320 attached along four sides of the outer portion of the second diffusion sheet 240 is attached along four sides of the mold frame 260. The double-sided tape 320 attached to four surfaces of the mold frame 260 is attached to the outer portion of the liquid crystal display panel 30.

The rear surface of the mold frame 260 seats and fixes the light guide plate 180. To this end, as shown in FIG. 9, the light guide pinning part seating part 270 is formed at a position corresponding to the light guide pinning part on the rear surface of the mold frame 260. The light guide pinning part is seated on the light guide pinning part seating part 270 and then fixed by sidewalls surrounding the light guide pinning part seating part 270. In addition, the rear surface of the mold frame 260 seats and fixes the reflective sheet 200. That is, the rear surface of the mold frame 260 seats the reflective sheet 200 after the light guide plate 180 is seated on the mold frame 260. To this end, a reflective sheet seating portion 280 is formed on the rear surface of the mold frame 260. The reflective sheet is fixed to the reflective sheet seating portion 280 and then fixed by sidewalls surrounding the reflective sheet seating portion 280.

The front surface of the mold frame 260 seats and fixes the first and second diffusion sheets 220 and 240. To this end, as shown in FIG. 10, an optical sheet ear seating portion 290 is formed at a position corresponding to the first and second diffusion sheet ear portions on the front of the mold frame 260. The first and second diffusion sheet ears are assembled to each other and seated on the optical sheet ear seat 290, and then fixed by sidewalls surrounding the optical sheet ear seat 290. After the first and second diffusion sheets are seated on the front of the mold frame 260, the liquid crystal display panel 30 is mounted. Then, the backlight unit 100 is fastened by fastening the top chassis 20 and the bottom chassis 310. ) And the liquid crystal display panel 30 and the mold frame 260 are fixed. In addition, the front surface of the mold frame 260 seats and adheres the light source unit 110. To this end, the light source unit seating portion 300 is formed on the front of the mold frame 260.

On the other hand, the embodiment of the present invention is applicable even when the optical sheet is composed of three or more. That is, a groove is formed in the ear portion protruding from the optical sheet located on the lowest layer, and the ear portion is formed perpendicular to the ear portion protruding from the optical sheet located on the top layer, and the ear portion protruding from the optical sheet located on the lowest layer is located on the top layer. After assembling up onto the protruding ear from the sheet, the double-sided tape may be attached to the protruding ear from the optical sheet located on the lowest layer to prevent the flow of the optical sheet.

As described above, the optical sheet of the present invention and the liquid crystal display having the same include ear parts formed to protrude from the optical sheet. Specifically, a groove is formed in the ear portion protruding from the optical sheet located on the lowermost layer, and the ear portion is formed perpendicular to the ear portion protruding from the optical sheet located on the uppermost layer. For this reason, it can be assembled so that the ear part which protruded from the optical sheet located in the lowest layer may go up on the ear part which protruded from the optical sheet located in the uppermost layer. Due to the assembly of the ear parts, it is possible to prevent the flow of the optical sheet, and to secure a high-quality liquid crystal display device in which foreign matter defects, white spot defects, and stains do not occur.

In the detailed description of the present invention described above with reference to the preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge of the present invention described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the spirit and scope of the art.

Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (12)

Optical sheet ear portion of the at least one optical sheet of the at least one of the at least one optical sheet having an optical sheet ear portion protruding from at least one side, the groove is formed by removing a portion. The method of claim 1, The groove is an optical sheet, characterized in that formed in the ear of the optical sheet of the optical sheet located on the lowest layer of the at least two optical sheets. The method of claim 2, And the optical sheet ear portion of the optical sheet positioned on the lowermost layer is assembled so as to be located above the optical sheet ear portion of the optical sheet positioned on the uppermost layer of the at least two optical sheets. The method of claim 1, The at least two optical sheets An optical sheet comprising two diffusion sheets for scattering light to spread evenly. The method of claim 1, The at least two optical sheets One diffusion sheet for scattering light and spreading the light evenly; An optical sheet comprising at least one prism sheet for increasing brightness by refracting and condensing light. The method of claim 5, The at least two optical sheets The optical sheet further comprises a luminance improving sheet for improving the luminance. A liquid crystal display panel for displaying an image; A light source unit providing light to the liquid crystal display panel; A light guide plate for guiding light from the light source unit to the liquid crystal display panel; And an optical sheet ear portion of at least one optical sheet of at least one optical sheet having an optical sheet ear portion formed on the light guide plate and protruding from at least one side thereof, wherein a portion of the optical sheet ear portion is removed to form a groove. The method of claim 7, wherein And the groove is formed at an ear of the optical sheet of the optical sheet positioned at the lowest layer of the at least two optical sheets. The method of claim 8, And the optical sheet ear portion of the optical sheet positioned on the lowermost layer is assembled to be located above the optical sheet ear portion of the optical sheet positioned on the uppermost layer of the at least two optical sheets. The method of claim 7, wherein The at least two optical sheets A liquid crystal display device comprising two diffusion sheets for scattering light and spreading the light evenly. The method of claim 7, wherein The at least two optical sheets One diffusion sheet for scattering light and spreading the light evenly; And at least one prism sheet for increasing brightness by refracting and condensing light. The method of claim 11, The at least two optical sheets And a luminance improving sheet for improving the luminance.

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