KR20070025971A - Backlight device and liquid crystal apparatus - Google Patents

Abstract

A back light unit and an LCD(Liquid Crystal Display) are provided to distinctly divide a turn on region and a turn off region using a simple configuration, improve brightness and secure brightness uniformity. A back light unit includes a light-emitting means(20), a transmitting means(11), barriers(6), and a reflecting means(7). The light-emitting means includes a plurality of light-emitting regions(8) that are arranged at a predetermined interval and emit light at different timings. The transmitting means receives light emitted from the light-emitting means. At least a part of the barriers is formed of a transparent material. The tops of the barriers come into contact with the transmitting means to divide the light-emitting means into the plurality of light-emitting regions. The reflecting means is attached to each barrier and reflects light emitted from the light-emitting regions.

Description

BACKLIGHT DEVICE AND LIQUID CRYSTAL APPARATUS}

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing which shows the structure of the liquid crystal display device which has the backlight device of Embodiment 1 which concerns on this invention.

FIG. 2 is a block diagram showing an example of a control and driving circuit in the liquid crystal display device of Embodiment 1. FIG.

3 is a cross-sectional view showing the vicinity of a junction between the diffusion plate 5 and the partition plate 6 in the backlight device according to the first embodiment of the present invention.

4 is a cross-sectional view showing a modification of the backlight device of Embodiment 1 of the present invention.

FIG. 5 is a cross-sectional view showing a configuration of a liquid crystal display device having a backlight device according to Embodiment 2 of the present invention. FIG.

Fig. 6 is a block diagram showing the configuration of a liquid crystal panel and a light emitting portion in the liquid crystal display device of the second embodiment.

FIG. 7 is a cross-sectional view showing a modification of the backlight device according to the second embodiment; FIG.

8 is a sectional view showing another modification of the backlight device according to the second embodiment;

9 is a cross-sectional view showing a configuration of a backlight device of Embodiment 3;

10 is a graph showing the results of a luminance experiment on a backlight device.

11 is a cross-sectional view showing Modification Example 1 in the backlight device of Embodiment 3;

FIG. 12 is a cross-sectional view illustrating Modification Example 2 (FIG. 9A) and Modification Example 4 (FIG. 9B) in the backlight device of Embodiment 3;

FIG. 13 is a cross-sectional view illustrating a method for fixing a partition plate according to the first to third embodiments. FIG.

14 is a cross-sectional view showing a configuration of a backlight device of Embodiment 4;

FIG. 15 is a cross-sectional view showing a specific configuration of a backlight device of Embodiment 4; FIG.

16 is a graph showing the results of experiments performed on a backlight device.

17 is a cross-sectional view showing Modification Example 1 in the backlight device of Embodiment 4;

18 is a cross-sectional view showing a modification 2 in the backlight device according to the fourth embodiment;

19 is a cross-sectional view showing a modification 3 in the backlight device of Embodiment 4;

(Explanation of symbols for the main parts of the drawing)

1: liquid crystal display device 2: liquid crystal panel

3: polarizing sheet 4: prism sheet

5: diffuser plate 6: partition plate

7: reflective sheet 8: emitting region

9: cold cathode fluorescent tube 10: backlight device

11: Floodlight 12: Bottom Reflector

13: liquid crystal panel control circuit 14: CCFL control circuit

15 CCFL drive circuit 16 LED light emitting unit

17: LED 18: LED control circuit

19: LED driving circuit 20: light emitting part

21: LED reflecting surface 22: internal reflecting portion

23: partition plate base 24: the body

Field of technology

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight device used for a liquid crystal display device and the like, in particular, a backlight device used for a liquid crystal display device suitable for moving picture display, and a liquid crystal display device using the backlight device.

Prior art

In recent years, liquid crystal display devices, such as a liquid crystal television receiver and a liquid crystal display device, are widely used as an image display apparatus with thin shape and low power consumption. In such a liquid crystal display device, since the responsiveness and contrast ratio are not sufficient due to the characteristics of the liquid crystal, in the case of moving images, there is a problem that an afterimage occurs and the image is displayed faintly. As a means to solve such a problem, the blink control which turns on and turns off several light sources sequentially in correspondence with the scanning line of a liquid crystal display device is proposed (for example, refer patent document 1).

In the backlight device which performs such a blink control, the light emission area | region provided in the vertical scanning direction (the direction which a scanning line scans) in a liquid crystal panel is divided | segmented. Light emitting elements serving as light emitting sources are provided in each of the divided light emitting regions, and these light emitting elements are controlled to turn on and off sequentially in synchronization with the vertical synchronizing signal input to the liquid crystal panel. In this manner, by sequentially lighting the light emitting regions in the vertical scanning direction in synchronization with the vertical synchronizing signal, only a predetermined period of time is displayed in the back state in which the liquid crystal responds to each pixel, so that a good moving picture display can be performed.

Patent Document 1: Japanese Patent Application Laid-Open No. 2003-029236

Patent Document 2: Japanese Patent Application Laid-Open No. 2001-337617

Patent Document 3: Japanese Patent Application Laid-Open No. 2002-072167

Patent Document 4: Japanese Patent Application Laid-Open No. 2002-268570

As described above, in the backlight device of the conventional liquid crystal display device, a plurality of light emitting regions are sequentially turned on and off in order to improve the display state of a blurred display image on a liquid crystal panel or the residual image display of a moving image. In order to further enhance the effect of the blinking operation, it is necessary to clarify the boundary between the area being turned on and the area being turned off. In the backlight device of the conventional liquid crystal display device, in order to form several light emitting area | region, the light emitting part is divided by the partition board etc. which consist of plate materials with thickness. These partition plates are disposed in close contact with a light transmitting plate such as a diffusion plate for diffusing light from the light emitting element. In this way, the partition plate is configured to divide the light emitting portion into a plurality of light emitting regions so that light does not leak into each light emitting region (see Patent Document 2, for example).

However, as described above, in a backlight device in which the end of the partition plate is in close contact with a back surface of a light transmitting plate such as a diffusion plate, when the plate thickness of the partition plate is thick, the portion of the thickness of the partition plate There is a problem that the light emitting area corresponding to the shape becomes dark in a linear shape and the uniformity of luminance of the entire backlight device which is a surface light emitting device is lowered. Therefore, although it is preferable to make the plate | board thickness of a partition plate infinitely thin, when it makes it too thin, problems, such as a strength problem and a bending, generate | occur | produce, and were very difficult in manufacture (for example, refer patent document 3).

As a means of solving the problem that the light emitting area corresponding to the part of the thickness of the partition plate becomes dark in a linear form, a structure for providing a gap between the rear surface of the diffusion plate and the top of the partition plate has been proposed (Example See, for example, Patent Document 1 and Patent Document 4). In such a configuration, the light emitting area is brightened by the light from the adjacent area, and the effect of the partition plate arrangement can be eliminated, but the light leakage and the unlit area are blurred by the light leaking from the adjacent area. Causes another problem. In addition, since such a partition plate must form a space having a predetermined gap between the diffusion plate, there is a problem that the manufacture of a backlight device using such a partition plate is not easy and the manufacturing cost is high.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described various problems in a conventional backlight device, and the simple structure makes it possible to clarify the boundary between the lit area and the unlit area, and also eliminates the adverse effect of the partition plate arrangement and improves the brightness. An object of the present invention is to provide a backlight device capable of ensuring uniformity and uniformity, and a liquid crystal display device capable of drawing a good moving image.

In order to achieve the above object, the backlight device of the first aspect of the present invention,

Light emitting means disposed at predetermined intervals from each other and having a plurality of light emitting regions emitting light at different timings,

Light-transmitting means through which light from the light-emitting means is incident,

A partition plate at least partially formed of a light-transmitting material, the top of which contacting the light-emitting means to divide the light-emitting means into a plurality of light-emitting regions, and

It is attached to the said partition plate, and is provided with the reflection means which reflects the light from the light emitting source in each light emission area | region. The backlight device of the present invention configured as described above can prevent the dark portion caused by the partition plate and become an excellent device capable of uniform surface light emission. In a preferred embodiment described later, the light emitting source is a cold cathode fluorescent tube (CCFL) or a light emitting diode (LED), the light emitting means is a light emitting portion 20, and the light transmitting means is a polarizing sheet 3, a prism sheet. It consists of 4 and the diffuser plate 5, and a reflection means is a reflection sheet 7, 7A, 7B. Although embodiment mentioned later demonstrates concretely using the said structure, this invention is not limited to these structures, Comprising: It is comprised including the thing with the same objective as the thing of these structures, and having the same function.

In the backlight device according to the second aspect of the present invention, one of the partition plates in which the partition plate in the first aspect is formed of a plate-like plate material and divides the light emitting means to define the light emitting area. The surface may be formed by attaching reflecting means of which both surfaces are reflective surfaces.

In the backlight device of the third aspect of the present invention, the partition plate in the first aspect is configured by at least two stacked plates, and the reflecting means is squeezed to the overlapping surface of the partition plate. You may comprise.

In the backlight device of the fourth aspect of the present invention, a cross section orthogonal to a plane defining a light emitting region in the partition plate of the first aspect is an isosceles triangle, and the vertex of the isosceles triangle is ) May be formed by attaching reflecting means to a part of the surface constituting two sides between the light transmitting means and sandwiching the vertex.

In the backlight device of the fifth aspect of the present invention, in the partition plate of the first aspect, a surface of the partition plate facing the light emitting source in the light emitting region reflects light from the light emitting source and is directed in the direction of the light transmitting means. You may comprise with the reflecting surface which exits.

A backlight device according to a sixth aspect of the present invention is a structure in which the reflecting means in the first to fifth aspects described above is attached to the partition plate with a gap of a predetermined distance from an end of the light transmitting means side. You may make it.

In the backlight device according to the seventh aspect of the present invention, a cross section orthogonal to the plane defining the light emitting region of the partition plate in the first aspect is formed of an isosceles triangular transmissive material, and the front of the partition plate ) Defines a light emitting area having the light emitting source in contact with the light projecting means, and the light transmitting means side end of the reflecting means adhered to both sides forming the step of the partition plate has a gap of a predetermined distance with respect to the light projecting means. It may be formed so that the vicinity of the bottom end side of the partition plate is exposed, and the light from the light emitting source is emitted from the top of the partition plate to the light transmitting means by a reflecting portion formed inside the partition plate.

A backlight device according to an eighth aspect of the present invention is provided with light emitting means having a plurality of light emitting regions which are arranged at predetermined intervals from each other and emit light at different timings;

Light-transmitting means through which light from the light-emitting means is incident, and

A cross section orthogonal to the plane defining the light emitting area has an isosceles triangle shape, and the partition of the isosceles triangle is formed of a light transmitting material and contacts the light emitting means to divide the light emitting means into a plurality of light emitting regions. And

The said partition plate is comprised so that it may have a reflecting surface which reflects the light from the light emitting source provided in the said light emitting area to the said light transmission means. The backlight device of the present invention configured as described above can prevent the generation of the dark portion caused by the partition plate with a simple configuration, and enables uniform surface light emission.

In the backlight device according to the ninth aspect of the present invention, the partition plate in the eighth aspect is composed of a government formed from a light-transmitting material and a loan connected to the government, May be configured as a reflective surface.

A liquid crystal display device according to a tenth aspect of the present invention includes a backlight device from the first to ninth aspects described above, and a liquid crystal panel to which light emitted from the light transmitting means of the backlight device is irradiated. The liquid crystal display device configured in this way can draw a good moving picture.

In the backlight device of the present invention, it is possible to clarify the boundary between the lit area and the unlit area, and to eliminate the problem that dark parts occur due to the partition plate arrangement, and to provide a planar light emitting device having a uniform luminance.

In addition, the liquid crystal display device of the present invention provides the advantages of the backlight device of the present invention by assembling the backlight device of the present invention having the excellent effects as described above, and reliably draws a good moving image without discomfort. It becomes possible to provide a liquid crystal display device which can be made.

EMBODIMENT OF THE INVENTION Hereinafter, the backlight device of the preferred embodiment which concerns on this invention, and the liquid crystal display device using this backlight device are demonstrated with reference to attached drawing.

In addition, in description of the following embodiment, the term which shows a specific direction (for example, "up", "low", etc.), and other terms (for example, "upward", "downward", etc.) containing those terms Although appropriately used, their use is intended to facilitate understanding of the invention with reference to the drawings, and the technical scope of the invention is not limited by their terms. Accordingly, the embodiment in which the embodiment of the present invention described below is inverted up and down or rotated by a predetermined angle (for example, 90 degrees) in an arbitrary direction (for example, in a clockwise or counterclockwise rotation) is also shown. Naturally, it belongs to the technical scope of this invention.

<< embodiment 1 >>

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the structure of the liquid crystal display device which has the backlight device of Embodiment 1 which concerns on this invention. In FIG. 1, in order to make description of the liquid crystal display device of Embodiment 1 easy, it is a figure which shows this liquid crystal display device typically, The magnitude | size and space | interval of each structure differ from an actual device.

As shown in FIG. 1, the liquid crystal display device 1 of Embodiment 1 is equipped with the liquid crystal panel 2 and the backlight apparatus 10 arrange | positioned behind this liquid crystal panel 2 (lower side in FIG. 1). It is a liquid crystal display device by direct surface type light emission. In addition, although abbreviate | omitted in FIG. 1, the electric circuit which performs light emission control and color adjustment is provided in the back surface of the backlight apparatus 10, and is formed as an integrated structure as the backlight apparatus 10. As shown in FIG. As the liquid crystal panel 2 in Embodiment 1, all the liquid crystal panels conventionally known are available, and the liquid crystal display device of this invention is not limited by the kind and panel structure of liquid crystal.

In the backlight device 10, a plurality of light transmitting plates 11 having functions such as light diffusion, condensing, polarization, and the like are stacked and disposed on the front surface (the surface facing the liquid crystal panel 2). In Embodiment 1, the structure of the several light transmission plate 11 is only the light component formed in the sheet form from the soft material and oscillating in a specific direction among incident light in order from the surface facing the liquid crystal panel 2 in order. A polarizing sheet 3 for transmitting, a prism sheet 4 for condensing incident light, and a diffusion plate 5 for diffusing the incident light.

The light emitting part 20 which has some cold cathode fluorescent tube (CCFL) 9 which is a light emitting source is provided behind the several light transmitting plate 11 comprised as mentioned above. The cold cathode fluorescent tube 9 is a straight tube extending in a direction perpendicular to the surface of Fig. 1, and is spaced at predetermined intervals according to a direction orthogonal to this extension installation direction (left and right direction in Fig. 1). For example, they are 200-400 mm and are arrange | positioned in parallel. The cold cathode fluorescent tube 9 is a light source for irradiating the liquid crystal panel 2 from the rear side, and the longitudinal direction thereof is arranged parallel to the horizontal scanning line direction. Each of the cold cathode fluorescent tubes 9 is arranged in parallel at equal intervals in the vertical scanning line direction.

As shown in FIG. 1, the light emitting part 20 is provided with a bottom side reflecting plate 12 on the rear surface of the cold cathode fluorescent tube 9, and the bottom side reflecting plate 12 includes a cold cathode fluorescent tube 9. It is fitted in the position facing the diffuser plate 5. In the light emitting portion 20, partition plates 6 formed of a light-transmitting material are provided on both sides of one cold cathode fluorescent tube 9 arranged in parallel with the horizontal scanning line direction. Each of the light emitting regions in the light emitting portion 20 is defined by the partition plate 6.

In the light emitting portion 20, a reflective sheet 7 serving as a reflecting means is attached to one side surface of the partition plate 6 defining the light emitting region. Both surfaces of the reflective sheet 7 are reflective surfaces having high reflectance (reflectivity of 90% or more). In Embodiment 1, an adhesive is applied to one surface of the reflective sheet 7 to the partition plate 6. Attached. The reflective sheet 7 used in Embodiment 1 was a sheet-like article formed of polyethylene terephthalate resin (PET), and had a reflectance of 96% and a thickness of 0.2 mm.

In addition, although the reflective sheet 7 of double-sided reflection was used as reflection means in Embodiment 1, the reflection means of this invention is not limited to such a structure, It can use if it is a thin film body which has a high reflectance. For example, a diffused film having high reflectivity such as a reflective film in which aluminum (Al) is deposited on a film of transparent polyethylene terephthalate resin (PET), a film of foamed polyethylene terephthalate resin that is totally reflected by fine bubbles, a white film or the like You may use a reflecting film body.

In addition, although the partition plate 6 in Embodiment 1 was formed with the acrylic resin with heat resistance, as a material of the partition plate 6, light transmission which has the outstanding light transmittance, such as an acrylic resin with heat resistance, a polycarbonate, etc. Material is used.

In the liquid crystal display device having the backlight device 10 of Embodiment 1 configured as described above, the light emitting portion 20 is divided into a plurality of light emitting regions having the cold cathode fluorescent tube 9 by the partition plate 6. It is. Control and driving circuits are connected to each of the divided light emitting regions, and lighting and extinguishing operations are performed independently.

FIG. 2 is a block diagram showing an example of a control and driving circuit in the liquid crystal display device of Embodiment 1. FIG. As shown in FIG. 2, the liquid crystal display device 1 of Embodiment 1 is provided with the liquid crystal panel control circuit 13 into which a video signal is input, and from this liquid crystal panel control circuit 13, the liquid crystal panel 2 is carried out. The drive signal of is supplied. By this drive signal, the scanning line and the signal line in the liquid crystal panel 2 are driven, and an image is displayed on the liquid crystal panel 2. In the backlight device 10, the CCFL control circuit 14 is provided in the light emitting unit 20 having the cold cathode fluorescent tube 9 (CCFL: Cold-cathode fluorescent lamp), and is perpendicular to the liquid crystal panel control circuit 13. The synchronization signal is configured to be input. As described above, each of the light emitting regions 8 divided into the plurality of partition plates 6 is provided with a CCFL driving circuit 15, and the cold cathode fluorescent tube 9 in each of the light emitting regions 8 is provided. Flashing drive control. The CCFL drive circuit 15 receives a drive signal output from the CCFL control circuit 14, and outputs a predetermined high frequency high voltage signal to the corresponding cold cathode fluorescent tube 9. Each cold cathode fluorescent tube 9 sequentially emits light in response to an input signal of a predetermined high frequency high voltage. Therefore, in synchronization with the vertical synchronizing signal of the video signal input to the liquid crystal display device 1, the cold cathode fluorescent tubes 9 of the respective light emitting regions 8 are sequentially turned on and off.

In the backlight device 10 according to the first embodiment configured as described above, when the cold cathode fluorescent tube 9 of each light emitting region 8 is sequentially subjected to blink control in which lighting and extinction are repeated, each light emitting region The light from the cold cathode fluorescent tube 9 in (8) is directly incident on the diffuser plate 5 and reflected by the reflective sheet 7 attached to the bottom reflector 12 or the partition plate 6. It is indirectly incident on the diffusion plate 5.

3 is a cross-sectional view showing the vicinity of the junction between the diffusion plate 5 and the partition plate 6 in the backlight device 10 of the first embodiment. As shown in FIG. 3, one surface of the partition plate 6 formed of a light-transmitting material is attached with a reflective sheet 7 whose both surfaces are reflective surfaces, and an upper surface of the partition plate 6 (diffusion plate 5). Cross section facing the surface) is formed into a flat surface and is in contact with the diffusion plate 5.

When all of the adjacent areas are lit, the light from the cold cathode fluorescent tube 9 of one light emitting region 8 (the light emitting region 8 on the left side in FIG. 3) enters the partition plate 6 and enters the partition plate. (6) It passes through the inside and is reflected by the reflecting sheet 7, and passes through the inside of the partition plate 6 again, and a part of it injects into the diffuser plate 5 from the upper end surface of the partition plate 6. For example, the light from the cold cathode fluorescent tube 9 passes through the optical paths shown by arrows L1 and L2 in FIG. 3, is reflected by the reflective sheet 7, and passes through the partition plate 6. Passes through and enters the diffusion plate 5. That is, part of the light incident on the partition plate 6 from one of the cold cathode fluorescent tubes 9 is guided by the partition plate 6 to contact the upper surface, which is the top portion thereof, and the contact surface of the diffusion plate 5. Is incident on the diffusion plate 5 from above.

On the other hand, the light from the cold cathode fluorescent tube 9 of the other light emitting region 8 (the light emitting region 8 on the right side in FIG. 3) is reflected sheet 7 which is attached to the opposing surface of the partition plate 6. ), Most of the light directly incident on (), for example, the light indicated by the broken arrow L3 in FIG. 3, is totally reflected in the direction of the diffuser plate 5 and is incident on the diffuser plate 5.

Therefore, light is emitted from the cold cathode fluorescent tube 9 in the partition plate 6 on both sides defining each of the light emitting regions 8, and the diffusion of the adjacent region, which is one boundary portion, is conducted. The plate 5 is irradiated, and the other partition plate 6 guides the light from the side cold cathode fluorescent tube 9 that faces the partition plate 6 so that The diffuser plate 5 is irradiated. As a result, in the backlight apparatus 10 of Embodiment 1 comprised as mentioned above, the partition plate 6 which defines each light emission area | region 8 has the light uniformly with respect to the whole diffuser plate 5. The incident light is diffused, and the incident light is diffused to pass through each light transmitting plate 11 to irradiate the liquid crystal panel 2.

In addition, although Embodiment 1 demonstrated the structure which attached the reflective sheet 7 of double-sided reflection to the one surface of the partition plate 6 with the adhesive agent, the partition plate 6 is made of two light-transmitting materials, for example. It is also possible to have a joining structure in which a plate member composed of the two members is bonded to each other, and the two-side reflecting means, for example, the reflective sheet 7, is clamped on the joining surface. 4 is a cross-sectional view showing a configuration in which the reflective sheet 7 is narrowed inside the partition plate 6 having a bonding structure. By configuring in this way, an adhesive agent becomes unnecessary, and the both surfaces of the reflective sheet 7 become the structure which has the same reflectance. Therefore, in the structure shown in FIG. 4, since the fall of the reflectance by the use of an adhesive agent can be prevented, and the reflective sheet 7 is protected by the partition plate 6 from both sides, the reflective sheet 7 The structure will be able to prevent secular changes.

As described above, in the backlight device according to the first embodiment, the partition between the lit area and the unlit area can be made clear by providing the thin film reflecting means on the partition plate 6 made of a light-transmitting material, and the partition plate is further provided. It is possible to prevent the dark portion from occurring and to ensure uniformity of luminance in the plane light emission. Further, by assembling the backlight device of Embodiment 1 into a liquid crystal display device, a liquid crystal display device capable of good moving picture display can be provided.

<< embodiment 2 >>

5 is a cross-sectional view showing the configuration of a liquid crystal display device having the backlight device according to the second embodiment of the present invention. In FIG. 5, it is a figure which shows typically the liquid crystal display device of Embodiment 2 in order to make description of each part easy like the liquid crystal display device of Embodiment 1 mentioned above, and is the magnitude | size and space | interval of each structure. Is different from the actual device. In the liquid crystal display device of Embodiment 2, a plurality of light emitting diode (LED) light emitting portions 16 are provided in parallel with one cold cathode fluorescent tube 9 which is a light emitting source in the liquid crystal display device of Embodiment 1. It is.

In the liquid crystal display device of Embodiment 2, the backlight device 10 is a polarizing sheet which is a light transmitting plate 11 on the front side (surface side facing the liquid crystal panel 2) of the backlight device 10, similarly to Embodiment 1. (3), the prism sheet 4, and the diffuser plate 5 are laminated | stacked in order from the surface which opposes the liquid crystal panel 2, and is provided.

Behind the floodlight plate 11 comprised as mentioned above, the light emission part 20 which has several LED light emission part 16 which is a light emitting source (planar light source) is provided. The light emitting part 20 is provided between a plurality of LED light emitting parts 16 arranged in a lattice shape at predetermined intervals, and each LED light emitting part 16 and on the bottom face side facing the liquid crystal panel 2, It is comprised including the bottom reflecting part 12 which has a reflecting surface. Each LED light emitting part 16 has a substantially square shape on a surface facing the liquid crystal panel 2 and has a plate-like appearance having a thickness. At the center of each LED light emitting portion 16, a light emitting diode (LED) 17, which is a light emitting element, is provided, and the LED 17 has three light emitting elements (red diodes) emitting red, green, and blue light. , A green diode, and a blue diode).

In each LED light emitting unit 16, an LED reflecting surface 21 is formed around the LED 17, which is a light guide means having a high reflectivity of a plate shape which is roughly curved downward. Each LED light emitting part 16 of Embodiment 2 is a base material which consists of a translucent material provided with the emission surface which opposes the light transmission board 11, and is a light emitting element embedded in this base material. The LED 17 and the LED reflecting surface 21, which is a light guide means for guiding the light generated by the LED 17 to the floodlight plate 11 in the whole or almost the entire area of the emission surface, is directed. It is composed with.

FIG. 6 is a block diagram showing the configuration of the liquid crystal panel 2 and the light emitting portion 20 in the liquid crystal display device 1 according to the second embodiment. As shown in FIG. 6, in the light emitting unit 20, a plurality of LED light emitting units 16 having a substantially square shape are disposed in a lattice form at predetermined intervals. The video signal is input to the liquid crystal panel control circuit 13, and a drive signal of the liquid crystal panel 2 is supplied from the liquid crystal panel control circuit 13. By this drive signal, the scanning line and the signal line in the liquid crystal panel 2 are driven, and an image is displayed on the liquid crystal panel 2. In the backlight device 10, the LED control circuit 18 is provided in the light emitting part 20 which has the LED light emitting part 16, and is comprised so that a vertical synchronization signal may be input from the liquid crystal panel control circuit 13. As shown in FIG. In addition, as described above, each of the light emitting regions 8 divided by the partition plate 6 is provided with LED driving circuits 19, and the LED light emitting portions 16 provided in the respective light emitting regions 8 are provided. Flashing drive control. The LED drive circuit 19 receives a drive signal output from the LED control circuit 18 and outputs a predetermined signal to the corresponding LED light emitting section 16. All of the LED light emitting units 16 in the respective light emitting regions 8 emit light in response to the input predetermined signals. Therefore, in synchronization with the vertical synchronizing signal of the video signal input to the liquid crystal display device 1, the LED light emitting portions 16 in each light emitting region 8 repeat lighting and extinguishing at the same time.

In the backlight device 10 of Embodiment 2 configured as described above, in case that the blink control in which the LED light emitting units 16 in each light emitting region 8 are repeatedly turned on and off is performed, each light emitting region ( The light from the LED light emitting part 16 in 8 is directly incident on the diffuser plate 5, and is reflected by the reflective sheet 7 attached to the bottom reflector 12 or the partition plate 6 and indirectly. Incident on the diffuser plate 5.

In the light in which the light from the LED light emitting portion 16 is reflected by the reflective sheet 7, the light incident on the partition plate 6 formed of the light-transmitting material passes through the partition plate 6 and is reflected by the reflective sheet ( Reflected at 7), part of which is guided toward the diffuser plate 5. In other words, part of the light incident on the partition plate 6 is incident on the diffuser plate 5 from the contact surface between the government part in the partition plate 6 and the diffuser plate 5.

On the other hand, most of the light directly incident on the reflective sheet 7 attached to the surface of the partition plate 6 facing the LED light emitting portion 16 is substantially totally incident to the diffuser plate 5.

Therefore, in the partition plates 6 on both sides defining each of the light emitting regions 8, the partition plate 6 guides the light from the LED light emitting section 16 to diffuse light 5 at one boundary portion. ), The other partition plate 6 guides the light from the side LED light emitting portion 16 that faces the partition plate 6 to irradiate the diffuser plate 5 at the other boundary portion. do. As a result, in the backlight device 10 of Embodiment 2 comprised as mentioned above, the partition plate 6 which defines each light emission area | region 8 has the light uniformly with respect to the whole diffuser plate 5. It is comprised so that it may inject and the incident light will decompose | disassemble and pass through each light transmission plate 11, and irradiate the liquid crystal panel 2 to it.

In the backlight device according to the second embodiment configured as described above, the partition between the lit area and the unlit area can be made clear by providing the thin film reflecting means on the partition plate 6 made of a light-transmitting material. By providing 6), it is possible to prevent the occurrence of the dark portion, and to ensure uniformity of luminance in surface light emission. Further, by assembling the backlight device of the second embodiment into a liquid crystal display device, a liquid crystal display device capable of good moving picture display can be provided.

The modification of the backlight device 10 in the liquid crystal display device 1 of Embodiment 2 is demonstrated using FIG. 7 is a cross-sectional view showing a modification of the backlight device 10 according to the second embodiment. In the modification shown in FIG. 7, the reflecting surface of the bottom reflecting plate 12 is arrange | positioned in the position of the edge part of the LED reflecting surface 21 in the side surface of the LED light-emitting part 16. As shown in FIG. In the bottom reflector 12, a through hole into which the partition plate 6 is inserted is formed at a position corresponding to the boundary of the light emitting region 8. The partition plate 6 is formed with two shading portions 64 and 64 that are elastic bodies. When the partition plate 6 is inserted into the through hole of the bottom reflector 12, the two shading portions 64 and 64 are formed. The bottom reflector 12 is configured to be squeezed by. Therefore, by fixing the bottom reflector 12 by the shade 64 and 64 of the partition plate 6, and arranging the LED light emitting part 16 fixed to the bottom reflector 12 in the body 24, The partition plate 6, the bottom reflector 12, and the LED light emitting portion 16 are reliably disposed at a predetermined position with respect to the body 24. In addition, in the structure shown in FIG. 7, since the bottom reflecting plate 12 is provided in the same position as the LED reflecting surface 21 in the side surface of the LED light emitting part 16, light from the LED light emitting part 16 is efficient. It can reflect highly, and the brightness can be improved.

Next, another modified example of the backlight device 10 in the liquid crystal display device 1 of Embodiment 2 is demonstrated using FIG. 8 is a cross-sectional view showing another modification of the backlight device 10 according to the second embodiment. In the modification shown in FIG. 8, the partition plate base 23 is provided below the partition plate 6. The partition plate base 23 has the shape of an isosceles triangle with a cross section orthogonal to the longitudinal direction (horizontal scanning line direction) of the partition plate 6. Both side surfaces of the partition plate base 23 are formed of reflective surfaces having high reflectance. The partition plate base 23 is integrally formed by joining the partition plate 6, and the position of the apex of the partition plate base 23 is that the junction point with the partition plate 6 is an LED. Light emitted from the side of the light emitting portion 16 on the diffuser plate 5 side than the light emitting surface 16A (upper side in FIG. 8) is emitted from the side of the partition plate base 23. It is configured to be incident directly. In the backlight device configured as described above, the light emitted from the side surface of the LED light emitting portion 16 is reflected from the side surface of the partition plate base 23 and is emitted in the direction of the diffusion plate 5. Therefore, in the backlight device 10 shown in FIG. 8, it is possible to further improve the luminance as the planar light source. In addition, the shape of the partition plate base 23 formed below the partition plate 6 is a shape in which an isosceles portion is formed in a concave surface in addition to an isosceles triangle, or light emitted from the side surface of the LED light emitting portion 16 such as a trapezoid. It can be applied as long as the shape is reflected in the direction of the diffusion plate 5. The partition plate 6 formed of the light-transmitting material and the partition plate base 23 may be integrally formed, and a reflective sheet having a reflective surface having a high reflectance may be attached to both sides of the partition plate base 23.

In the liquid crystal display device 1 of Embodiment 2 comprised as mentioned above, since it is drive-controlled by the structure shown in the block diagram of FIG. 6, LED in each light emitting area 8 in the backlight device 10 is shown. When blink control is performed in which the light emitting portion 16 simultaneously turns on and disappears, the light from each light emitting region 8 is divided by the partition plate 6 defining each light emitting region 8. Only the corresponding diffuser plate 5 is irradiated, and the return of light from the adjacent light emitting region 8 is prevented. In the liquid crystal display device 1 according to the second embodiment, the partition plate 6 is formed of a light-transmitting material, and the partition plate 6 is configured such that light passes from the partition plate 6 to the diffusion plate 5 at its contact surface. For this reason, in the diffuser plate 5, it does not become a dark part by the shadow of the partition plate 6, but becomes a planar light-emitting device with uniform luminance as a backlight device.

As described above, in the backlight device of the second embodiment, the boundary between the lighting area and the unlit area can be clarified by providing the reflecting means in the partition plate made of the light-transmitting material, and the effect is eliminated by providing the partition plate. Uniformity of luminance in the planar light emitting device can be ensured. Further, by assembling the backlight device of the second embodiment into a liquid crystal display device, a liquid crystal display device capable of good moving picture display with high luminance can be provided.

<< embodiment 3 >>

EMBODIMENT OF THE INVENTION Hereinafter, the backlight device used for the liquid crystal display device of Embodiment 3 which concerns on this invention is demonstrated. The backlight device of Embodiment 3 is configured of the backlight device described in Embodiment 1 (use of cold cathode fluorescent tube (CCFL) 9) or Embodiment 2 (use of LED light emitting portion 20) described above. Is an example of modifying the shape and configuration of the partition plate and the reflective sheet. The configuration of the backlight device according to the third embodiment achieves the same effect in each of the first and second embodiments. Therefore, in description of Embodiment 3, the same code | symbol is attached | subjected to what has the function and the structure similar to the element in Embodiment 1 and 2, and the description applies description in each embodiment.

FIG. 9 is a sectional view showing the backlight device of the third embodiment and showing the vicinity of the contact portion between the diffusion plate 5 and the partition plate 6 in the backlight device 10 of the third embodiment. As shown in FIG. 9, the reflective sheet 7A attached to one surface of the partition plate 6 has a distance A from the rear surface (lower surface in FIG. 9) of the diffusion plate 5. It is arranged. Therefore, the part of distance A from the contact surface of the diffusion plate 5 and the partition plate 6 is the state which the partition plate 6 formed from the translucent material exposed. This reflective sheet 7A has the same structure as the reflective sheet 7 described in Embodiment 1 described above on both surfaces thereof.

Thus, since the reflective sheet 7A is disposed at a constant distance A from the rear surface of the diffuser plate 5, the shadow of the shadow by the reflective sheet 7A at the boundary portion in the adjacent light emitting region 8 is determined. The influence is eliminated, and the generation of the dark portion at the interface at the time of the surface light emission is reliably prevented.

By experiment, the inventors found that the distance A from the diffusion plate side end portion of the reflective sheet 7A to the back surface of the diffusion plate 5 is preferably 0.0 mm or more and 3.0 mm or less, and 0.3 mm or more and 1.5 mm or less. It was confirmed that the following are particularly preferable distances. If the distance A exceeds 3.0 mm, the light quantity at the boundary surface can be prevented as surface light emission. However, when the adjacent light emission areas are the light-on area and the light-off area, the boundary becomes unclear and becomes blurred. .

FIG. 10 is a graph showing results of luminance experiments performed on a backlight device when a partition plate is not provided or when a partition plate having a different configuration is used. In the luminance test, the LED light emitting part 16 having a 22 mm angle was used, the distance between the partition plates 6 was 32 mm, and the diffuser plate 5 was formed from the diffusion plate side end portion of the reflective sheet 7A. The distance A to the back surface was 0.7 mm. Further, the distance from the reflecting surface of the bottom reflecting plate 12 on which the LED light emitting part 16 is placed to the back surface (lower surface in FIG. 10) of the diffuser plate 5 is set to 25 mm and is incident on the diffuser plate 5. The luminance value of the light to be measured was measured.

Fig. 10A shows the relative luminance value when the adjacent light emitting regions 8 are the lit area and the unlit area. FIG. 10B shows the relative luminance value when both of the adjacent light emitting regions 8 are lit regions. Here, the relative luminance value is 1.0, and the ratio is the ratio of the luminance value at the position to the highest luminance value. In FIG. 10, the graph shown by the broken line is a relative luminance value when a partition plate is not provided, and the graph shown by the dashed-dotted line shows the edge part using the conventional partition plate which is not a light transmitting member having a plate thickness of 2 mm. It is a relative luminance value in the case of the structure adhere | attached on a diffuser plate, and the graph shown by a solid line is a relative luminance value in the case of using the structure of the backlight device of Embodiment 2 shown in FIG.

As shown in Fig. 10 (a), in the configuration of Embodiment 2 shown by the solid line, the conventional partition plate shown by the dashed-dotted line with respect to the performance of preventing leakage light from the lit area to the unlit area is shown. Is equivalent to the case where the structure is in close contact with the diffuser plate, and the leakage light from the boundary portion of the light emitting region 8 to the adjacent region can be reduced by about 75% as compared with the case where the partition plate shown by the broken line is not provided. have.

On the other hand, as shown in Fig. 10B, in the configuration of Embodiment 2 shown by the solid line, the light emitting region 8 is compared with the case where the conventional partition plate shown by the dashed-dotted line is in close contact with the diffusion plate. An increase in the relative luminance value of about 35% is observed at the boundary portion of), and the luminance equivalent to that in the case where the partition plate shown by the broken line is not provided is secured.

As is clear from the experimental results shown in FIG. 10, in the backlight device 10 according to the second embodiment, the boundary between the lit area and the unlit area is made clear, and the light emitting area 8 as the planar light source is also provided. The fall of the brightness | luminance by a partition plate at the boundary in this case does not arise, and it becomes a planar light emitting device with high uniformity.

In the structure shown in FIG. 9, the light which passed through the partition plate 6 totally reflects in the interface which is a contact surface of the diffuser plate 5 and the partition plate 6 (optical path shown by the code | symbol B in FIG. 9), Light leaking from the exposed portion of the partition plate 6 on which the reflective sheet 7A is not provided to the adjacent light emitting region 8 (optical path shown by reference C in FIG. 9) is generated. The partition plate 6A shown in FIG. 11 is configured such that light is incident on the diffusion plate 5 corresponding to the boundary portion of the light emitting region 8.

FIG. 11 shows Modification Example 1 in the backlight device of Embodiment 3, and shows the vicinity of the contact portion between the diffusion plate 5 and the partition plate 6A in Modification Example 1. FIG. It is a timed section. As shown in FIG. 11, the cross section orthogonal to the longitudinal direction of the shape near the contact part with the diffuser plate 5 in 6 A of partition plates has a triangular-roof shape (prism shape comprised from a triangular shape). Have At the apex (upper part in FIG. 11) of this prism-shaped part (top part), it is in linear contact with the diffuser plate 5. In the prism shape part which is the government part of 6 A of partition plates shown in FIG. 11, the 1st prism surface which is 61 the one exit surface which comprises a right angle, and the 2nd symbol 62 which comprises a right angle Prism plane. In 6 A of partition plates, the angle (right angle) between the 1st prism surface 61 and the 2nd prism surface 62 is 90 degrees.

On one side of the side of the partition plate 6A described above, a portion other than the government portion is provided with a reflecting sheet 7A which is a reflecting means. That is, similar to Embodiment 3 shown in FIG. 9 mentioned above, the reflective sheet 7A is arrange | positioned with the space | interval of the vertical distance A from the back surface (lower surface in FIG. 11) of the diffuser plate 5. As shown in FIG. Therefore, the prism-shaped part in the part of the vertical distance A from the contact surface of the diffuser plate 5 and the partition plate 6A is the state which the partition plate 6A of the translucent material exposed.

Thus, since the part of 6 A of partition plates is formed in the prism shape, and 7 A of reflection sheets are not provided in the part of the prism shape, for example, the 1st prism surface (6) passes through the partition plate 6A, The light reaching 61 is refracted by the first prism face 61 to irradiate the boundary portion of the diffuser plate 5 directly above the partition plate 6A (see the optical path D in FIG. 11). . Similarly, the light passing through the partition plate 6A and reaching the second prism face 62 is refracted by the second prism face 62, so that the diffusion plate 5 is directly above the partition plate 6A. The boundary portion is irradiated (see the optical path E in FIG. 11). Therefore, in the structure shown in FIG. 11, the light which passed through the partition plate 6A is irradiated to the boundary part of the light emitting area 8 divided | segmented by the partition plate 6A, and the brightness | luminance in the boundary part is shown. Improvement is planned. Therefore, in the backlight device 10 including the partition plate 6A and the reflective sheet 7A shown in FIG. 11, the occurrence of dark portions at the time of planar light emission at the boundary portion of each light emitting region 8 is prevented. In addition, there is an excellent effect that the interface between the lit area and the unlit area becomes clear.

12 is a cross-sectional view showing Modification Example 2 (FIG. 9A) and Modification Example 3 (FIG. 9B) in the backlight device 10 of Embodiment 3, wherein partition plates 6B are shown. 6C) shows a part near the contact portion with the diffusion plate 5. In the modification 2 shown to Fig.9 (a), the government part which is a contact part with the diffuser plate 5 in the partition plate 6B is formed so that it may have a semicircular cross section. In the modification 3 shown to FIG. 9B, the contact part with the diffuser plate 5 in 6 C of partition plates is formed so that it may have several triangular roof shape (plural prism shape) cross sections. Thus, since the government of partition plates 6B and 6C is comprised in various shapes, the light which passed through the interior of partition plates 6B and 6C and reached the government with respect to the boundary part of the light emitting area 8 is desired. Since it can be comprised so that it may irradiate with an optical path, it becomes possible to control the light emission state in the boundary part to desired luminance.

FIG. 13: is sectional drawing which showed the specific fixing method of each partition plate 6, 6A, 6B, 6C in Embodiment 1 thru | or Embodiment 3. In FIG. Although the partition plate 6 is demonstrated in FIG. 13, it can fix also in other partition plates 6A, 6B, 6C by the same fixing method.

In the fixing method illustrated in FIG. 13A, a groove 12A is formed in the bottom reflector 12, and the end portions of the partition plate 6 and the reflective sheet 7 are inserted into the groove 12A. ) And is fixed by an adhesive. In this fixing method, the partition plate 6 and the bottom reflecting plate 12 may be screwed for reinforcement.

In the fixing method shown in FIG. 13B, a through hole 12B is formed in the bottom reflector 12, and a pin 63 formed at the bottom of the partition plate 6 is inserted into the through hole 12B. It is a method of fixing by.

In the fixing method illustrated in FIG. 13C, the bottom reflection plate 12 is provided with a through hole 12C, while the bottom portion of the partition plate 6 is provided with the sunshade 64 disposed to face each other with elasticity. 64) is formed. The space | interval of the shade part 64 and 64 which opposes is set by the thickness of the bottom reflector 12. When the partition plate 6 is fixed to the bottom reflection plate 12, one of the sunshades 64 formed on the bottom side of the partition plate 6 is inserted into the through hole 12C of the bottom reflection plate 12 and penetrated therethrough. . Thereby, the bottom reflecting plate 12 is clamped by the shade parts 64 and 64 on both sides, and the partition plate 6 with the reflecting sheet 7 is firmly fixed to the bottom reflecting plate 12.

In the backlight device 10 used for the liquid crystal display device 1 of Embodiment 3 comprised as mentioned above, the partition boards 6, 6A, 6B, 6C of various shapes and configurations, and the reflecting means are provided in the partition board. By providing, the generation | occurrence | production of the dark part at the time of planar light emission in the boundary part of each light emission area | region 8 is prevented, and it has the outstanding effect that the interface surface of a lighting area and an unlit area | region becomes clear.

<< embodiment 4 >>

Hereinafter, the backlight device used for the liquid crystal display device of Embodiment 4 which concerns on this invention is demonstrated. The backlight device of Embodiment 4 is an example in which the shape and configuration of the partition plate and the reflecting means are modified in the configuration of the backlight device described in Embodiment 1 or Embodiment 2 described above. Therefore, in the description of the fourth embodiment, the partition plate and the reflecting means will be described, and the other components have the same functions and configurations as those described in the first and second embodiments. The description is omitted.

FIG. 14 is a cross-sectional view showing the backlight device 10 according to the fourth embodiment, showing a partition plate 6D and a reflecting sheet 7A serving as reflecting means. In the partition plate 6D according to the fourth embodiment, the cross section orthogonal to the longitudinal direction (horizontal scanning line direction) is an isosceles triangle, and the vertex is in contact with the back surface (lower surface in FIG. 14) of the diffusion plate 5. . In addition, at two sides (both sides of the partition plate 6D defining the light emitting region 8) that form the vertex, the reflective sheet is formed on the portion from the vertex to the bottom with an interval of a predetermined vertical distance (A). 7A) is attached. Therefore, the part from the contact point of the diffuser plate 5 and the partition plate 6D to the vertical distance A is the state where the partition plate 6D which is a translucent material is exposed.

As described above, since the reflective sheet 7A having the high reflectivity reflective surface is arranged at a distance of a constant distance A from the rear surface of the diffuser plate 5, the reflective sheet (at the boundary portion of the light emitting region 8) The occurrence of the dark part by 7A) is prevented. As for the vertical distance A from the diffuser side side edge part of the reflective sheet 7A to the back surface of the diffuser plate 5, 0.0 mm or more and 3.0 mm or less are preferable distances similarly to Embodiment 3 mentioned above, and 0.3 mm or more and 1.5 Mm or less is a particularly preferable distance.

FIG. 15 is a sectional view of a specific example in which the backlight device 10 is configured by using the partition plate 6D and the reflective sheet 7A shown in FIG. 14. In addition, although only the diffuser plate 5 of the transparent plate 11 is shown in FIG. 15, the polarizing sheet 3, the prism sheet 4, and the diffusion sheet are actually arranged in the transparent plate 11 as shown in FIG. The board 5 is provided. As shown in FIG. 15, in this specific example, the diffusion plate 5 is a plate-shaped material having a thickness of 2 mm, and the distance from the reflection surface of the bottom reflector 12 to the back surface of the diffusion plate 5 is 25. Mm. Moreover, the space | interval of the partition plate 6 was 32 mm, the length of the base of the partition plate 6 was 8 mm, and the LED light-emitting part 16 used the square shape of 22 mm angle.

FIG. 16 is a graph showing an experimental result regarding the distance A from the back surface of the diffuser plate 5 to the reflective sheet 7A using the backlight device 10 (FIG. 15) configured as described above. . In this experiment, the luminance value of the light incident on the diffuser plate 5 from the LED light emitting portion 16 was measured.

Fig. 16A shows the relative luminance value when the adjacent light emitting regions 8 are the lit area and the unlit area. FIG. 16B shows the relative luminance value when both of the adjacent light emitting regions 8 are lit regions. Here, the relative luminance value is 1.0, and the ratio is the ratio of the luminance value at the position to the highest luminance value. In Fig. 16, the graph shown by the broken line is the relative luminance value when the vertical distance A is 0.3 mm, and the graph shown by the solid line is the relative luminance value when the vertical distance A is 0.7 mm, one point. The graph shown by the dashed lines is a relative luminance value when the vertical distance A is 1.5 mm.

As shown in Fig. 16A, in the configuration of the fourth embodiment, if the vertical distance is between 0.3 mm and 1.5 mm, it is clearly divided at the interface between the lit area and the unlit area, and the preferred result is obtained. You can get it.

In addition, as shown in Fig. 16B, in the configuration of Embodiment 4, the vertical distance is 0.3 mm with respect to the influence of the partition plate at the boundary of the light emitting region 8 at the time of planar light emission. To 1.5 mm, generation of a dark portion at the interface between the lit area and the lit area is suppressed, and a preferable result can be obtained.

As described above, in the backlight device 10 according to the fourth embodiment, the light emitting regions 8 are defined using the partition plate 6D and the reflective sheet 7A, thereby providing respective light emitting regions 8. The light from the light emitting source in E is reflected on the reflective surface of the reflective sheet 7A, the back surface of the diffuser plate 5 is irradiated with high efficiency, and the brightness as a planar light source is improved. Further, since the light incident on the portion exposed by the light-transmitting material of the partition plate 6D is refracted to irradiate the boundary portion of the light emitting region 8 in the diffusion plate 5, the backlight of the fourth embodiment is used. The device improves the luminance at the boundary portion of the light emitting region 8 and becomes a uniform surface light emitting device.

17 is a cross-sectional view showing Modification Example 1 of the backlight device of Embodiment 4, showing partition plate 6E and reflective sheet 7B serving as reflection means. The partition plate 6E in the modification 1 of Embodiment 4 is a shape in which the cross-sectional shape orthogonal to a longitudinal direction (horizontal scanning line direction) curved the part of the isosceles in an isosceles triangle. The curved portion has a concave surface in the direction toward the light emitting source, and reflects light from the light emitting source in the direction of the diffusion plate 5. In the partition plate 6E of the first modified example, the vertex of the partition plate 6E contacts the back surface (lower surface in FIG. 17) of the diffusion plate 5 similarly to the partition plate 6D shown in FIG. 14 described above. The reflection sheet 7B is attached to the side surface portion of the partition plate 6E from the position having the predetermined distance A to the bottom side from the apex. Therefore, the reflective sheet 7B adheres to the side surface of the partition plate 6E except for the top portion, and is formed in a concave surface shape. This reflective sheet 7B has a reflective surface of high reflectance similarly to the reflective sheets 7 and 7A shown in Embodiments 1 to 3 and FIG. 14 described above.

As described above, since the reflective sheet 7B having the high reflectivity reflective surface is disposed at a constant distance A from the rear surface of the diffuser plate 5, the reflective sheet at the boundary portion in the adjacent light emitting region 8 is provided. The influence of the shadow by 7B is eliminated, and the generation of the dark portion at the boundary surface of the planar light source is reliably prevented.

As shown in FIG. 17, by forming the partition plate 6E and the reflective sheet 7B, the reflection surface in which the light from the light emitting source in each light emitting area 8 has the curvature of the reflective sheet 7B Is reflected, the back surface of the diffusion plate 5 is irradiated with high efficiency, and the brightness as a planar light source is improved. In addition, since the light incident on the portion exposed by the light-transmitting material of the partition plate 6E is refracted to irradiate the boundary portion of the light emitting region 8 in the diffusion plate 5, the luminance at the boundary portion Can be improved to achieve uniformity in the planar light source.

18 is a cross-sectional view showing Modification Example 2 in the backlight device of Embodiment 4, showing the vicinity of partition plate 6F in contact with the back surface of diffusion plate 5. In the modification 2 of Embodiment 4, the partition plate 6F is an isosceles triangle whose cross section orthogonal to a longitudinal direction (horizontal scanning line direction). In addition, the partition plate 6F is comprised by the top part 65 of the part containing the vertex contacting the diffuser plate 5, and the large part 66 arrange | positioned at the bottom face side of this part 65. As shown in FIG. The top portion 65 is made of a light transmitting material, and the large portion 66 is formed of a resin having high reflectance. The distance from the top, which is the height of the government 65, to the bottom is set to A. FIG. In the step 65 composed of a light transmitting material, light from the light emitting region 8 is incident and refracted to irradiate the boundary portion of the diffuser plate 5. In addition, the light reflected by the diffuser plate 5 and returned to the government unit 65 totally reflects at the bottom of the government unit 65 and again irradiates the boundary portion of the diffusion plate 5. In addition, the reflection surface which is the surface of the large part 62 of the partition plate 6F of this modification 2 totally reflects the light from a light emitting source, etc., and irradiates the back surface of the diffuser plate 5.

As shown in FIG. 18, by configuring the partition plate 6F, light from the light emitting source in the light emitting region 8 divided by the partition plate 6F is reflected on the reflective surface of the large portion 66. Then, the back surface of the diffuser plate 5 is irradiated with high efficiency, and the brightness of the planar light emitting device is improved. In addition, since the partition plate 6F is provided with a stepping portion 65 made of a light-transmitting material, the light incident on the stepping portion 65 is refracted to form a boundary portion of the light emitting region 8 in the diffusion plate 5. In order to irradiate, the brightness | luminance in the boundary part improves and it becomes a planar light emitting device which has a uniform light emitting surface.

FIG. 19 is a cross-sectional view showing Modification Example 3 of the backlight device of Embodiment 4, showing partition plate 6G, reflective sheet 7A, and the like in contact with the back surface of diffusion plate 5. In the modification 3 of Embodiment 4, the partition plate 6G comprised from the translucent material is an isosceles triangle whose cross section orthogonal to the longitudinal direction (horizontal scanning line direction), and its vertex is the back surface of the diffuser plate 5 ( The lower surface in Fig. 19). Moreover, in two sides (side surface of the light emitting area | region 8) in which the said vertex was formed, it is double-sided in the part from the position which has a predetermined vertical distance A from the said vertex, to the position which has a vertical distance F from a base 7 A of reflective sheets which have this high reflectivity are stuck. Therefore, the part from the contact point of the diffuser plate 5 and the partition plate 6G to the vertical distance A, and the part from the bottom surface of the partition plate 6G to the vertical distance F are partition plates 6G of light-transmitting material. ) Is exposed.

In addition, in the partition plate 6G of the modification 3 shown in FIG. 19, the internal reflecting part 22 is formed in the inner bottom face side. The internal reflection part 22 is an isosceles triangle (approximate equilateral triangle in this modified example 3) orthogonal to the longitudinal direction (horizontal scanning line direction) of 6 G of partition plates, and the vertex is the direction of the diffuser plate 5 Heading up. The surface of the two sides corresponding to the isosceles in the internal reflecting portion 22 is a reflecting surface having a high reflectance. Therefore, light incident on the portion of the vertical distance F from the bottom surface of the partition plate 6G is reflected by the internal reflection portion 22 and proceeds in the direction of the diffuser plate 5 (upward in FIG. 19). . In this way, the light reflected by the internal reflecting portion 22 is reflected from the inner surface side of both reflective sheets 7A and 7A attached to the inclined surface that is the side surface of the partition plate 6G, and thus the apex of the partition plate 6G. Investigate the backside of the diffuser plate 5 by exiting from the government having a.

As described above, in the backlight device 10 of the third modification shown in FIG. 19, the light from the light emitting source of the light emitting region 8 is incident from the inner bottom side of the partition plate 6G, and the internal reflecting portion 22 ), It passes through the inside of the partition plate 6G and irradiates the boundary portion of the diffusion plate 5 from the government. As a result, according to the structure of the modification 3 shown in FIG. 19, since it is a structure which light irradiates the boundary part of the light emitting area | region 8 in the diffuser plate 5 through the inside of the partition plate 6G, The luminance at the boundary portion is improved and a planar light emitting device having a uniform light emitting surface is obtained.

As mentioned above, although preferred embodiment of the backlight device which concerns on this invention, and the liquid crystal display device using the backlight device was described, the above-mentioned embodiment can be variously improved. For example, although an example using a cold cathode fluorescent tube (CCFL) and three light emitting diodes each generating red, green, and blue light as light emitting sources has been described, any light emitting device used as a light emitting source can be applied to the present invention. .

This invention is useful in the field of the backlight device used for a liquid crystal display device.

In the backlight device of the present invention, it is possible to clarify the boundary between the lit area and the unlit area, and to eliminate the problem that dark parts occur due to the partition plate arrangement, and to provide a planar light emitting device having a uniform luminance.

In addition, the liquid crystal display device of the present invention provides the advantages of the backlight device of the present invention by assembling the backlight device of the present invention having the excellent effects as described above, and reliably draws a good moving image without discomfort. It becomes possible to provide a liquid crystal display device which can be made.

Claims (10)

Light emitting means disposed at predetermined intervals from each other and having a plurality of light emitting regions emitting light at different timings, Light-transmitting means through which light from the light-emitting means is incident, A partition plate at least partially formed of a light-transmitting material, the government contacting the light-emitting means to divide the light-emitting means into a plurality of light-emitting regions, and And a reflecting means attached to said partition plate and reflecting light from a light emitting source in each light emitting region. The method of claim 1, And said partition plate is constituted by a plate-like plate material, and on one side of said partition plate which divides said light emitting means to define said light emitting region, reflecting means having both surfaces being reflective surfaces. The method of claim 1, And said partition plate is constituted by at least two overlapping plates, and said reflecting means is squeezed to the overlapping surface of said partition plate. The method of claim 1, The reflecting means is a part of a surface of the partition plate orthogonal to a plane defining an emission region, and an isosceles triangle, the vertex of the isosceles triangle contacting the light projecting means, and a part of a surface constituting two sides sandwiching the vertices. The backlight device characterized by the above. The method of claim 1, In the partition plate, wherein at least a part of the surface of the light emitting area facing the light emitting source is configured as a reflecting surface that reflects light from the light emitting source and exits in the direction of the light transmitting means. The method according to any one of claims 1 to 5, And the reflecting means is attached to the partition plate with a gap of a predetermined distance from an end of the light transmitting means side. The method of claim 1, A cross section orthogonal to the plane defining the light emitting area is formed of a triangular transmissive material, and the government of the partition plate contacts the light emitting means to define a light emitting area having the light emitting source, and the top of the partition plate The light transmitting means side end part of the said reflecting means attached to both surfaces which form | formed is formed with the clearance gap of a predetermined distance with respect to the said light emitting means, and the reflecting part formed in the inside of the said partition plate by exposing the vicinity of the bottom side of the partition plate side. And the light from the light emitting source is emitted from the top of the partition plate to the light projecting means. Light emitting means disposed at predetermined intervals from each other and having a plurality of light emitting regions emitting light at different timings, Light-transmitting means through which light from the light-emitting means is incident, and A cross section orthogonal to the plane defining the light emitting area has an isosceles triangle shape, and the partition of the isosceles triangle is formed of a light transmitting material and contacts the light emitting means to divide the light emitting means into a plurality of light emitting regions. And The partition plate is configured to have a reflecting surface that reflects light from a light emitting source provided in the light emitting region to the light transmitting means. The method of claim 8, A partition plate is composed of a government formed from a light-transmitting material and a loan continued to the government, and the interface between the government in the loan is configured as a reflective surface. A liquid crystal display device comprising the backlight device according to any one of claims 1 to 9 and a liquid crystal panel to which light emitted from the light transmitting means of the backlight device is irradiated.

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