CN101556403B - Liquid crystal display device - Google Patents

Abstract

A liquid crystal display device. An LCD device according to an embodiment of the present invention includes: an LCD panel including liquid crystal; and a backlight unit including: an LED array including a plurality of Light Emitting Diodes (LEDs) having peripheral LEDs disposed at peripheral ends of the LED array; and a light guide plate disposed under the LCD panel, each LED having a light emitting surface to emit light toward a light incident surface of the light guide plate. The light emitting surface of the peripheral LED completely covers the peripheral end portion of the light incident surface, which is an area adjacent to the side surface of the light guide plate.

Description

liquid crystal display device

technical field

The present invention relates to a liquid crystal display device, and particularly relates to mixing desired colors in a light guide plate and displaying them by arranging side surfaces of the light guide plate and ends of light emitting surfaces of light emitting devices disposed at both ends of a light emitting device array to be flush with each other. It is a liquid crystal display device that eliminates the bad color separation phenomenon of the outer and edge parts of the light guide plate by emitting light.

Background technique

The present disclosure is related to subject matter contained in prior Korean Patent Application No. 10-2008-0033342 filed Apr. 10, 2008, the entire content of which is hereby incorporated by reference.

Recently, a cathode ray tube (CRT), which is one of commonly used display devices, is mainly used as a monitor for televisions, measuring devices, information terminal devices, and the like. However, due to the weight and size of the CRT, the CRT cannot be actively applied to small-sized and light-weight electronic products. Thus, the CRT is limited in the tendency of various electronic products to become small and light. As an alternative to the CRT, there are liquid crystal display (LCD) devices utilizing a light effect of an electric field, plasma display panels (PDP) utilizing a gas discharge, and electroluminescent display (ELD) devices utilizing a light effect of an electric field. Among these devices, LCD devices are being actively researched.

In order to replace the CRT, an LCD device has recently been developed having advantages such as small size, light weight, and low power consumption, making it sufficient to be used as a flat panel display device. Thus, the LCD device is used as a monitor of a desktop computer and a large-sized information display device, and a display device for other purposes. Therefore, the demand for LCD devices continues to grow.

The LCD device can be roughly divided into a liquid crystal display panel for displaying images and a driving unit for applying driving signals to the liquid crystal display panel. The liquid crystal display panel includes first and second glass substrates coupled to each other at a predetermined interval and a liquid crystal layer injected between the first and second glass substrates.

Meanwhile, since the LCD device is mainly implemented as a light receiving device that displays an image by adjusting the amount of a light source, it is necessary to have a separate light source for irradiating light onto the liquid crystal panel, that is, a backlight. Backlights are classified into edge type and direct type according to where the lamp unit is installed.

The light source may be realized as electroluminescence (EL), light emitting diode (LED), cold cathode fluorescent lamp (CCFL), external electrode fluorescent lamp (EEFL), or the like. Among these light sources, the CCFL type is actively used for large-screen color TFT LCDs because it can be configured to have a long life and low power consumption and be thin. The CCFL type utilizes a fluorescent discharge tube in which mercury (Hg) gas added with argon (Ar), neon (Ne), etc. is filled and sealed at a low pressure to achieve a penning effect.

Electrodes are formed at both ends of the discharge tube. The cathode is formed in a plate shape. When a voltage is applied, charged particles in the discharge tube collide with the plate-shaped cathode and thereby generate secondary electrons, similar to the phenomenon of sputtering. Accordingly, surrounding elements are excited, thereby forming plasma. This causes surrounding elements to radiate intense ultraviolet light. Next, the ultraviolet rays excite the fluorescent substance, so that the fluorescent substance radiates visible light.

The above-mentioned side light type means that the lamp unit is mounted on a side surface of the light guide plate that guides light. The lamp unit has a lamp that radiates light, a lamp holder inserted into both ends of the lamp to protect the lamp, and a lamp that reflects light radiated from the lamp to the light guide plate by surrounding an outer peripheral surface of the lamp and inserting one side surface into a side surface of the light guide plate. Light reflector. An edge-light type in which a lamp unit is mounted on a side surface of a light guide plate is generally applied to relatively small LCD devices such as monitors of laptop computers and desktop computers. Its advantages are that light is uniformly irradiated, it has a long service life, and it is easy to form an LCD device in the form of a thin film.

According to the edge type backlight unit, light radiated from fluorescent lamps is collected on a light incident surface of a light guide plate, and then sequentially passed through a light guide plate, a diffusion plate, and a prism sheet to a liquid crystal display panel. However, the backlight unit using the fluorescent lamp of the related art has a low color reproduction range due to the light emitting characteristics of the light source itself. Due to size and capacity limitations of fluorescent lamps, it is difficult to obtain a backlight unit with high luminance.

Meanwhile, as LCD devices of a large size (for example, more than 20 inches) begin to be developed, a direct type that differs from the side-light type in the position and arrangement of light sources has been actively developed. The direct type is realized by arranging a plurality of lamps in a row on the lower surface of the diffusion plate, and then directly irradiating light to the front surface of the liquid crystal panel. Since the direct-type backlight unit has higher light utilization efficiency than the edge-type backlight unit, it is mainly used in a large-screen LCD device requiring high brightness.

The above-mentioned edge-type and direct-type backlight units utilize fluorescent lamps as light sources. However, due to concerns about harmful gases filled in fluorescent lamps, research into new light sources has recently been conducted. Among available light sources, LEDs are attracting attention as new light sources because LEDs do not cause environmental pollution, can realize various colors, and can reduce power consumption.

Hereinafter, a related art LCD device using an LED light source will be explained with reference to FIGS. 1 to 5 .

FIG. 1 is a cross-sectional view schematically showing an LCD device having a backlight unit according to the related art.

FIG. 2 is a plan view schematically showing an arrangement structure of an LED array and a light guide plate according to the related art.

FIG. 3 is a diagram schematically showing an LED array according to the related art.

FIG. 4 is a diagram schematically showing an LED array and a light guide plate according to the related art.

5 is a front view schematically showing an undesirable color separation phenomenon that occurs when light is incident on the light guide plate in a state where the light guide plate and the LED array are spaced apart from each other by a predetermined distance (D) in the LCD device according to the related art. .

As shown in FIG. 1 , an LCD device according to the related art includes a liquid crystal display panel 70 displaying an image and a backlight unit 10 emitting light to the liquid crystal display panel 70 . Here, in the liquid crystal display panel 70, although not shown, liquid crystals are filled between the upper substrate and the lower substrate. In addition, the liquid crystal display panel 70 has spacers for maintaining a uniform gap between the upper and lower substrates. The upper substrate of the liquid crystal display panel 70 has a color filter, a common electrode, a black matrix, and the like. The lower substrate of the liquid crystal display panel 70 has signal lines such as data lines and gate lines. In addition, thin film transistors (TFTs) are formed at intersections of the data lines and the gate lines. The TFT is used to convert a data signal from the data line to be transmitted to the liquid crystal cell in response to a scan signal (gate pulse) from the gate line. Also, a pixel electrode is formed in a pixel region between the data line and the gate line. The upper polarizing plate is bonded on the upper substrate of the liquid crystal display panel and the lower polarizing plate is bonded on the lower substrate of the liquid crystal display panel.

Meanwhile, as shown in FIGS. 1 and 2 , the backlight unit 10 includes a light guide plate 30 disposed opposite to the liquid crystal display panel 70 , and a reflective plate 20 disposed below the LED array. The LED array includes a plurality of LEDs 11 composed of red, green, and blue LEDs 11R, 11G, 11B respectively disposed opposite to one side surface of the light guide plate 30 . In addition, the backlight unit 10 further includes an optical sheet 60 disposed between the light guide plate 30 and the liquid crystal display panel 70 . The backlight unit 10 is inserted by fixing the main bracket 17 with the bottom case 21 .

The optical sheet 60 is divided into vertical optical sheets 61 and horizontal optical sheets 62 . Here, the optical sheet 60 serves to increase the front-end luminance of light passing through the optical sheet 60 . That is, the optical sheet 60 is configured to transmit light only at a specific angle. In addition, light incident at other angles is reflected due to internal total reflection in the optical sheet 60 and thus returns to the lower portion of the optical sheet. Then, the returned light is reflected by the reflection plate 20 .

As shown in FIGS. 2 to 4 , an LED array composed of a plurality of LEDs 11 is fixed on a package circuit board (PCB) 13 formed of a metal material, and the PCB 13 is installed in a main frame 17 . In addition, a connector 80 is provided at an edge portion of the upper surface of the PCB 13 to electrically connect each LED 11 of the LED array to an external driving circuit via a cable 15 .

In addition, light guide plate stoppers 19 are provided at both edge portions inside the main bracket 17 to protect the LEDs 11 and the light guide plate 30 from product vibration and prevent LED damage due to contact between the LEDs 11 and the light guide plate 30 . Here, the light guide plate stoppers 19 are disposed on both sides corresponding to both edge portions of the light guide plate 30 within the main bracket 17 to contact and thereby support the two edge portions of the light guide plate 30 . The light guide plate stopper 19 is slightly higher than the LED 11 to contact and support the light guide plate 30 while maintaining a certain distance between the LED 11 and the light guide plate 30 . Therefore, it is possible to prevent the light guide plate 30 from directly contacting the LED array due to product vibration.

Here, as shown in FIGS. 1 and 2 , the LED array is arranged to be separated from the light incident surface 30 a of the light guide plate 30 by a predetermined distance (D) corresponding thereto. Here, the red LED 11R and the blue LED 11B disposed at the outermost portions of both edge portions of the LED array are spaced inwardly by a predetermined distance from both side ends of the light incident surface 30 a of the light guide plate 30 . In addition, as shown in FIGS. 3 and 4 , the connector 80 is provided at a position corresponding to an edge portion of the light incident surface 30 a adjacent to the side surface of the light guide plate 30 , that is, at an edge portion of the upper surface of the PCB 13 .

However, LCD devices according to the related art have the following problems. In the LCD device according to the related art, emitted light cannot be realized as white but only other colors. That is, when using R, G, B LEDs, according to the wavelength and light intensity of R, G, B or the arrangement position and order of the R, G, B LED arrays, the red LED emits red light at the left end of the light guide plate and the red light on the left end of the light guide plate The right end of the blue LED emits blue light, as shown in "A" and "B" in Figure 5. Since the light guide plate and the LED array are separated from each other by a predetermined gap (eg, 'D' of FIG. 1 ), red light is emitted at the left end of the light guide plate and blue light is emitted at the right end of the light guide plate. Specifically, due to a color separation phenomenon occurring at an edge portion of the LCD device (ie, both ends of the light guide plate), desired white light cannot be reproduced at the end of the light incident portion of the light guide plate.

The reason for the color separation phenomenon is as follows. Since the light emitted from the LED disposed at the end of the LED is relatively stronger than the light emitted from the adjacent LED, even when power is precisely supplied to the respective LEDs, other colors cannot be realized by the end of the light incident portion of the light guide plate. LEDs reproduce the desired white light.

Meanwhile, in the LCD device according to the related art, since the number of LEDs in the related art is higher than when white LEDs are used, power consumption and heat increase. To control the heat gain, metal PCBs are used in LCD devices. When using a metal PCB in an LCD device, additional cables and connectors are required to connect the LED driver unit.

Thus, LEDs cannot be disposed on one edge portion of the upper surface of the metal PCB where the LED array is disposed. In addition, since the cables and connectors are disposed on the edge portion of the upper surface of the metal PCB, the available space for disposing LEDs on the metal PCB is reduced, whereby the number of LEDs that can be disposed on the metal PCB may be reduced.

In addition, in order to prevent damage to the LED array due to contact between the LED array and the light guide plate, light guide plate stoppers (LGP stoppers) should be additionally provided at both edge portions of the main frame and separated from the PCB on which the LED array is provided. Therefore, the structure of the LCD device becomes complicated and the manufacturing cost of the LCD device increases.

Contents of the invention

Therefore, an object of the present invention is to provide a method for mixing desired colors in a light guide plate to emit light by arranging side surfaces of the light guide plate and ends of light emitting surfaces of LEDs disposed at both ends of an LED array to be flush with each other, An LCD device that eliminates undesirable color separation at the outer and edge portions of the light guide plate.

Another object of the present invention is to provide an LCD device capable of solving limitations and disadvantages of the related art.

To achieve these and other advantages, and in accordance with the purposes of the present invention, as specifically and broadly described herein, the present invention provides an LCD device comprising: a liquid crystal display panel, a light guide plate disposed below the liquid crystal display panel, And an LED array composed of a plurality of LEDs, wherein the side surfaces of the LEDs arranged at both ends of the plurality of LEDs are flush with the two side surfaces of the light guide plate, and the light-emitting surfaces of the LEDs are arranged to be incident on the light of the light guide plate approaching.

In addition, according to another embodiment of the present invention, there is also provided an LCD device, which includes: a liquid crystal display panel, a light guide plate disposed under the liquid crystal display panel, and an LED array composed of a plurality of LEDs, wherein At least half of light emitting surfaces of LEDs disposed at both ends of the plurality of LEDs overlap light incident surfaces adjacent to side surfaces of the light guide plate, and the light emitting surfaces of the LEDs are disposed close to the light incident surface of the light guide plate.

In another aspect, embodiments of the present invention provide an LCD panel including liquid crystals; and a backlight unit comprising: a light emitting diode (LED) array including a plurality of LEDs having LEDs disposed on the LED array peripheral LEDs at the peripheral end of the LCD panel; and a light guide plate disposed under the LCD panel, each LED has a light emitting surface to emit light to a light incident surface of the light guide plate, wherein the light emitting surface of the peripheral LEDs completely covers the A peripheral end portion of the light incident surface, which is a region adjacent to the side surface of the light guide plate.

In yet another aspect, an embodiment of the present invention provides a backlight unit for a liquid crystal display (LCD) device, the backlight unit comprising: a light emitting diode (LED) array including a plurality of LEDs having peripheral LEDs at peripheral ends of the LED array; and a light guide plate disposed under the LCD panel, each LED having a light emitting surface to emit light to a light incident surface of the light guide plate. The light emitting surface of the peripheral LED completely covers the peripheral end of the light incident surface, which is a region adjacent to the side surface of the light guide plate.

In yet another aspect, embodiments of the present invention provide a liquid crystal display (LCD) device including: an LCD panel including liquid crystals; and a backlight unit including: a light emitting diode (LED) including a plurality of LEDs. ) array, and a light guide plate arranged under the LCD panel, each LED has a light emitting surface to emit light to the light incident surface of the light guide plate, wherein the light emitting surface of the LED and the light incident surface of the light guide plate The gap between them is a sufficient distance for the light of the LED within the viewing angle range of the light of the LED to be incident on the light guide plate.

The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

Description of drawings

The accompanying drawings, which are included in this specification to provide a further understanding of the invention, are incorporated in this specification and constitute a part of this specification, illustrate the embodiments of the present invention, and together with the specification serve to explain the concept of the present invention. principle.

In the attached picture:

1 is a cross-sectional view schematically showing an LCD device having a backlight unit according to the related art;

2 is a plan view schematically showing an arrangement structure of an LED array and a light guide plate according to the related art;

FIG. 3 is a diagram schematically showing an LED array according to the related art;

4 is a diagram schematically showing an LED array and a light guide plate according to the related art;

5 is a front view schematically showing an undesirable color separation phenomenon that occurs when light is incident on the light guide plate in a state where the light guide plate and the LED array are spaced apart from each other by a predetermined distance (D) in the LCD device according to the related art;

6 is a cross-sectional view showing an LCD device according to a preferred embodiment of the present invention;

Fig. 7 is a diagram schematically showing an LED array according to a preferred embodiment of the present invention;

8 is a diagram schematically illustrating an LED array and a light guide plate according to a preferred embodiment of the present invention;

9 is a plan view schematically showing the arrangement of an LED array and a light guide plate according to a preferred embodiment of the present invention;

10 is a plan view schematically showing an arrangement structure of an LED array and a light guide plate according to another embodiment of the present invention; and

11 schematically shows that in an LCD device according to a preferred embodiment of the present invention, the end portions of the light-emitting surfaces of the LEDs arranged at both ends of the LED array are set close to the side surface of the light guide plate when light is incident The front view showing that the bad color separation phenomenon at both ends of the light incident surface of the light guide plate is eliminated when reaching the light guide plate.

Detailed ways

Obviously, the invention described herein can be modified in different ways. Such modifications are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications will be obvious to those skilled in the art and are intended to be included within the scope of the appended claims.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 6 is a cross-sectional view showing an LCD device according to a preferred embodiment of the present invention.

Fig. 7 is a diagram schematically showing an LED array according to a preferred embodiment of the present invention.

FIG. 8 is a diagram schematically showing an LED array and a light guide plate according to a preferred embodiment of the present invention.

FIG. 9 is a plan view schematically showing an arrangement structure of an LED array and a light guide plate according to a preferred embodiment of the present invention.

FIG. 10 is a plan view schematically showing an arrangement structure of an LED array and a light guide plate according to another embodiment of the present invention.

11 schematically shows that in an LCD device according to a preferred embodiment of the present invention, the end portions of the light-emitting surfaces of the LEDs arranged at both ends of the LED array are set close to the side surface of the light guide plate when light is incident The front view showing that the bad color separation phenomenon at both ends of the light incident surface of the light guide plate is eliminated when reaching the light guide plate.

As shown in FIG. 6 , the LCD device according to the present invention includes a liquid crystal display panel 170 displaying an image and a backlight unit 100 emitting light to the liquid crystal display panel 170 . In addition, a plurality of optical sheets 161 and 162 are disposed under the liquid crystal display panel 170 .

Here, in the liquid crystal display panel 170, although not shown, liquid crystals are filled between the upper substrate and the lower substrate. In addition, the liquid crystal display panel 170 has a spacer for maintaining a uniform gap between the upper substrate and the lower substrate. The upper substrate of the liquid crystal display panel 170 has a color filter, a common electrode, a black matrix, and the like. In addition, the lower substrate of the liquid crystal display panel 170 has signal lines such as data lines and gate lines. Thin film transistors (TFTs) are formed at intersections of the data lines and the gate lines. The TFT is used to convert a data signal from the data line to be transmitted to the liquid crystal cell in response to a scan signal (gate pulse) from the gate line. Also, a pixel electrode is formed in a pixel region between the data line and the gate line.

In addition, pad regions to which data lines and gate lines are respectively connected are formed on one side of the lower substrate. In addition, a tape carrier package (TCP, not shown) in which a driving IC applies a driving signal to the TFT is bonded on the pad area. The TCP is used to supply data signals from the driver integrated circuit to the data lines and scan signals to the gate lines. In addition, an upper polarizing plate is bonded to an upper substrate of the liquid crystal display panel and a lower polarizing plate is bonded to a lower substrate thereof.

Meanwhile, as shown in FIGS. 6 to 8 , the backlight unit 100 includes a light guide plate 130 disposed opposite to the liquid crystal display panel 170 , a reflective plate 120 disposed under the plurality of LEDs 110 , 110 a. The plurality of LEDs is composed of red, green, and blue LEDs 11R, 11G, 11B respectively disposed opposite to the light incident surface 130a of the light guide plate 130 to form an LED array. In addition, the backlight unit 100 further includes an optical sheet 160 disposed between the light guide plate 130 and the liquid crystal display panel 170 , wherein the optical sheet 160 includes a plurality of optical sheets 161 and 162 . Here, as the backlight unit 100 becomes smaller, thinner, and lighter, the LED used as a light source has advantages in power consumption, thickness, weight, and brightness compared to a fluorescent lamp generally used as a backlight unit.

The backlight unit 100 may be fixed by the main bracket 117 . The liquid crystal display panel 170 disposed on the upper portion of the backlight unit 100 may be protected by a top case (although not shown). In this case, the top case and the main frame 117 may be connected to each other to accommodate the backlight unit 100 and the liquid crystal display panel 170 therebetween.

Meanwhile, as shown in FIG. 7 and FIG. 8, LEDs 110, 110a forming an LED array are disposed on a non-conductive flexible printed circuit board (PCB) 113, and are composed of a plurality of red, green, and blue LEDs 110R, 110G, 110B. Specifically, among the LEDs 110 , 110 a disposed on the flexible PCB 113 and forming an LED array, the LEDs 110 a disposed at both edge portions are disposed in a manner of being rotated by a certain angle relative to the adjacent LEDs 110 . For example, the LED 110a may be arranged to be rotated by a certain angle, such as 90°, relative to the adjacent LED 110 in the vertical direction. In addition, a light guide plate stopper (LGP stopper) 119 for preventing damage to the LEDs 110, 110a and the light guide plate 130 due to contact between the LED 110 and the light guide plate 130 is provided at a space 113a of the PCB 113 obtained by rotating the LED 110a by a certain angle. . Here, the LGP stopper 119 is disposed adjacent to the LEDs 110 a disposed at both edge portions of the PCB 113 to contact and support both edge portions of the light guide plate 130 .

Preferably, the LGP barrier 119 is slightly higher than the LEDs 110 , 110 a of the LED array to contact and support the light guide plate 130 while maintaining a certain distance between the LEDs 110 , 110 a and the light guide plate 130 . Therefore, it is possible to prevent the light guide plate 130 from coming into contact with the LEDs 110, 110a due to product vibration. Specifically, the LGP blocking member 119 has a sufficient height so that the LEDs 110 , 110 a do not contact the light incident surface 130 a of the light guide plate 130 . In addition, the LGP stopper 119 may be formed to weaken or absorb impact. For example, the LGP barrier 119 may be formed of a flexible material such as rubber or a material that can weaken or absorb shock. For example, the LGP stopper 119 may also include an elastic spring type device to weaken or absorb shock.

In addition, a metal plate 115 connected with the LED driving circuit is connected to the lower surface of the flexible PCB 113 . Here, the metal plate 115 serves to prevent the flexible PCB 113 from being bent and to prevent heat generated from a plurality of LEDs from increasing. The flexible PCB 113 connects the metal plate 115 electrically connected with the driving circuit of the LED array to a non-conductive flexible PCB (FPCB) 113 without using a conventional metal PCB and cables and connectors for the conventional metal PCB. Therefore, it is possible to remove the conventional connector and additionally provide the LED 110a at the position where the connector was removed. That is, the LEDs 110 a are disposed in spaces obtained at both edge portions of the FPCB 113 . The driving circuit of the plurality of LEDs 110, 110a includes a control circuit for emitting light from the LEDs 110R, 110G, 110B as point light sources generating light of a specific color such as red, green, and blue.

Meanwhile, the plurality of optical sheets 161, 162 are used to diffuse light emitted from the light guide plate 130 and bend the light path to be perpendicular to the liquid crystal panel 170, thereby improving light efficiency. Here, the optical sheet 160 may be configured as a vertical optical sheet 161 and a horizontal optical sheet 162, or as a single optical sheet. In addition, the optical sheet 160 may be configured as more than two optical sheets, such as a plurality of vertical optical sheets and/or horizontal optical sheets. Here, the optical sheet 160 serves to increase front-end brightness of light transmitted therethrough. That is, the optical sheet 160 is configured to transmit light only at a specific angle. In addition, light incident at other angles is reflected due to internal total reflection of the optical sheet 160 and thus returns to the lower portion of the optical sheet. Then, the returned light is reflected by the reflection plate 120 again.

Meanwhile, as shown in FIG. 9 , the light emitting surfaces 111 of the LEDs 110 , 110 a are provided to be closely opposed to the light incident surface 130 a of the light guide plate 130 . Here, the LEDs 110 and 110 a are close to the light incident surface 130 a without contacting the light incident surface 130 a of the light guide plate 130 . Specifically, the gap between each light-emitting surface 111 of the plurality of LEDs 110 , 110 a and the light incident surface 130 a of the light guide plate 130 provides a sufficient distance so that light within the viewing angle range of the light of the LEDs 110 , 110 a is incident on the light guide plate 130 . The viewing angle of an LED is the angle measured relative to the central axis through the center of the lens of the LED at which the light intensity is reduced to half the central axis light intensity. In this case, the gap distance between each light emitting surface 111 of the plurality of LEDs 110, 110a and the light incident surface 130a of the light guide plate 130 may be equal to or smaller than the width of each LED.

As shown in FIG. 9 , respective outer ends of the light emitting surfaces 111 of the LEDs 110 a disposed at both ends of the LED array are disposed on the same straight line as the side surfaces 130 b of the light guide plate 130 . That is, respective ends of the light emitting surfaces 111 of the LEDs 110 a disposed at both ends of the LED array are disposed flush with the side surfaces 130 b of the light guide plate 130 . Here, the LEDs 110a disposed at both ends of the LED array may be implemented as any one of red, green, and blue LEDs. In addition, as shown in FIG. 9 , each LED 110 , 110 a of the LED array is disposed close to the light incident surface 130 a of the light guide plate 130 , so all or most of the light emitted from each LED 110 , 110 a enters the light guide plate 130 . Specifically, when the left and right side surfaces 130b of the light guide plate 130 are arranged flush with the respective ends of the light emitting surfaces of the LEDs 110a of the LED array, the viewing angle of the LEDs 110a is approximately ±50˜60° according to the light emitting direction. Meanwhile, when the end of the light emitting surface 111 of the LED 110a is disposed flush with the side surface 130b of the light guide plate 130 , all or most of the light emitted from the LEDs 110 , 110a of the LED array enters the light guide plate 130 .

As shown in FIG. 10 , in an LCD device according to another embodiment of the present invention, when the LEDs 110 of the LED array are provided, at least more than half of the light-emitting surface 111 of the LEDs 110a and the light from the side surface 130b of the adjacent light guide plate 130 In the state where the incident surfaces 130a overlap, or when at least less than half of the light emitting surface 111 of the LED 110a is exposed from the side surface 130b of the light guide plate 130, the LEDs 110a are disposed at both ends to approach the light incident surface 130a. Here, light emitted from LEDs 110 and 110 a enters light guide plate 130 .

Thus, the embodiment of the present invention discloses that by setting the side surface 130b of the light guide plate 130 and the end of the light emitting surface 111 of the LED 110a to be flush with each other according to one embodiment, or setting the ends of the LEDs 110a of the LED array to be flush with each other according to another embodiment. At least more than half of the light emitting surface 111 is disposed to overlap the light incident surface 130a adjacent to the side surface 130b of the light guide plate 130, thereby disposing the light emitting surface 111 of the LED and the light incident surface 130a of the light guide plate close to each other. When one of these embodiments is used according to the invention, there is no longer an optical brightness difference between the area in which the LED 110a emits light and the area in which the adjacent LED 110 emits light. As shown in 'C' in FIG. 11 , the luminance ratio based on the color of white light may be maintained even at both ends of the light guide plate 130 . Thus, embodiments of the present invention can eliminate non-mixing regions (such as "A" or "B" shown in FIG. 5 ) where different colored lights in the effective light emitting region of the backlight cannot be properly mixed into white light.

Thus, a white flat fluorescent lamp is formed through which light is uniformly incident on the light guide plate 130 from the LEDs 110 , 110 a of the LED array.

The LCD device according to the preferred embodiment of the present invention has the following advantages.

In the LCD device according to the present invention, in a state where the side surfaces of the light guide plate and the ends of the light emitting surfaces of the LEDs provided at both ends of the LED array are arranged flush with each other, the light emitting surfaces of the LEDs and the light incident surface of the light guide plate are arranged close to each other, or at least more than half of the light emitting surfaces of the LEDs are arranged to overlap the light incident surfaces adjacent to the side surfaces of the light guide plate. Therefore, all or most of the light emitted from the LED array is incident into the light guide plate.

Thus, there is no longer an optical brightness difference between the area where an LED emits light and the area where an adjacent LED emits light. Thereby, the luminance ratio based on the color of white light can be maintained even at the end of the light guide plate, and thus it is possible to eliminate a non-mixing area where light in the effective light emitting area of the backlight cannot be mixed into white light.

In addition, the light-emitting surface of the LED and the light-incident surface of the light guide plate are disposed close to each other, so it is possible to eliminate undesirable color separation at the edge portion in the backlight unit emitting from the side. Therefore, it is possible to enhance the quality of the screen and apply the screen to every model of the backlight unit using the light guide plate.

In addition, according to the embodiment of the present invention, the connector is not provided on the PCB together with the LED array, and the LEDs are arranged in such a manner that they are rotated at a certain angle (for example, 90°) relative to the adjacent LEDs that the connector would be provided in the related art. s position. Next, a light guide plate stopper is provided at a space obtained by the PCB to prevent the LEDs and the light guide plate from contacting each other. Therefore, the space of the product can be effectively used. In addition, since the LED can be additionally disposed at the end of the PCB, it is possible to improve the light efficiency of the product.

The above-described embodiments and advantages are exemplary only, and should not be construed as limiting the present disclosure. These teachings are readily applicable to other types of devices. This description is illustrative, and does not limit the scope of the claims. Many alternatives, modifications and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein can be combined in various ways to obtain additional and/or alternative exemplary embodiments.

As this feature may be embodied in a variety of forms without departing from its characteristics, it should be understood that the above embodiments are not limited to any details of the foregoing description, unless otherwise specified, but rather to be implemented broadly within the scope defined in the appended claims. It is understood and therefore embraced by the appended claims that all changes and modifications come within the metes and bounds of the claims, or within equivalents of said metes and bounds.

Claims (11)

1. liquid crystal display LCD equipment, this liquid crystal display LCD equipment comprises:

The LCD panel that comprises liquid crystal; And

Back light unit, this back light unit comprises:

The led array that comprises a plurality of LEDs, described led array is arranged on the flexible printed circuit board PCB, described a plurality of LED has the peripheral LED of the peripheral end portion that is arranged on described led array, wherein said peripheral LED is set to and adjacent LED approximate vertical, wherein by being set to the described peripheral LED of described adjacent LED approximate vertical to have the space in two marginal portions of described flexible printed circuit board PCB, and in described space, be provided with the light guide plate block piece with contact and support described light guide plate; And

Be arranged on the light guide plate below the described LCD panel, each LED has light-emitting area with the light entrance face emission light to described light guide plate,

The light-emitting area of wherein said peripheral LED covers the peripheral end portion of described light entrance face fully, and the peripheral end portion of described light entrance face is the side surface adjacent areas with described light guide plate.

2. LCD equipment according to claim 1, the gap between the light-emitting area of wherein said LED and the light entrance face of described light guide plate are to make light in the angular field of view of the light that is in described LED of described LED can incide the sufficient distance on the light guide plate.

3. LCD equipment according to claim 1 wherein is provided with sheet metal below described flexible printed circuit board PCB.

4. LCD equipment according to claim 1, wherein said light guide plate block piece is set to be higher than described LED.

5. LCD equipment according to claim 1, wherein said light guide plate block piece comprise can absorb or weaken elastic construction or the resilient material that impacts.

6. LCD equipment according to claim 5, described elastic construction or described resilient material included in the wherein said light guide plate block piece are respectively spring or rubber.

7. LCD equipment according to claim 1, this LCD equipment also comprises and is clipped in the optical sheet between described LCD panel and the described light guide plate and is arranged on reflecting plate below the described light guide plate, with scattering from the light of described light guide plate irradiation and with the path turnover of described light for vertical with described LCD panel.

8. LCD equipment according to claim 1, this LCD equipment also comprises main support and the drain pan that is connected to each other and holds described LCD panel and described light guide plate betwixt.

9. LCD equipment according to claim 1, the peripheral end portion of half and the described light entrance face at least of the described light-emitting area of wherein said peripheral LED overlaps.

10. LCD equipment according to claim 1, the side surface of described peripheral LED that wherein is arranged on described led array end is corresponding with the described side surface of described light guide plate, and the described light entrance face of whole light-emitting areas of described peripheral LED and described light guide plate overlaps.

11. a back light unit that is used for liquid crystal display LCD equipment, this back light unit comprises:

The led array that comprises a plurality of LEDs, described led array is arranged on the flexible printed circuit board PCB, described a plurality of LED has the peripheral LED of the peripheral end portion that is arranged on described led array, wherein said peripheral LED is set to and adjacent LED approximate vertical, wherein by being set to the described peripheral LED of described adjacent LED approximate vertical to have the space in two marginal portions of described flexible printed circuit board PCB, and in described space, be provided with the light guide plate block piece with contact and support light guide plate; And

Described light guide plate is arranged on below the described LCD panel, and each LED has light-emitting area with the light entrance face emission light to described light guide plate,

The described light-emitting area of wherein said peripheral LED covers the peripheral end portion of described light entrance face fully, and the described peripheral end portion of described light entrance face is the side surface adjacent areas with described light guide plate.

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