WO2013046790A1 - Backlight device and liquid crystal display device using same - Google Patents

Abstract

Provided are a backlight device that can improve utilization efficiency for light from a light source and obtain a high quality image and a liquid crystal display device using the same. The backlight device has a plurality of backlight blocks on a chassis. Each backlight block is provided with: a reflective member, which is a bottom surface side of the backlight block and is provided on the chassis; a sheet shaped optical element provided so as to face the reflective member and disposed in a direction orthogonal to a light irradiation surface of the backlight at a prescribed distance from the reflective member; a plurality of LEDs disposed in the space between the optical element and the reflective member with light emitted in a direction parallel to the light irradiation surface of the backlight; and dividing plates that are between the LEDs and divide the space in a direction parallel to the light irradiation surface and the direction that light is emitted. The light from the light source passes through the optical element while being repeatedly reflected within the space between the optical element and the reflective member and propagated and is guided to a liquid crystal panel side.

Description

Backlight device and liquid crystal display device using the same

The present invention relates to a backlight device and a liquid crystal display device using the same, and more particularly, to a backlight device using a side view type LED (Light Emitting Diode) as a light source and a liquid crystal display device using the same.

Since the liquid crystal display device does not emit light by itself, a backlight device is arranged on the back of the liquid crystal display panel. In a backlight device used for a liquid crystal display device having a relatively large screen such as a television display device, a fluorescent tube has been used as a light source (see Patent Document 1).

Patent Document 1 discloses an edge light type (side view type) backlight device and an invention in which the backlight device is applied to a liquid crystal display device having a liquid crystal panel 10. In the backlight device of Patent Document 1, in order to transmit light toward the liquid crystal panel, a light guide plate disposed so as to overlap the liquid crystal panel, a fluorescent tube as a light source disposed on a side portion of the light guide plate, It has a condenser that collects the light from the fluorescent tube in a relatively small angle range and enters the light toward the light guide plate. In addition, the fluorescent tube has a U-shaped reflector in its cross section having an internal reflection layer.
The light guide plate of Patent Document 1 is made of a transparent plate such as an acrylic resin. A diffusion sheet is provided on one surface (hereinafter, the liquid crystal display panel side is referred to as an upper surface), and a diffusion reflection layer (reflection) is formed on the lower surface. Sheet) is provided. The diffuse reflection layer is obtained by providing diffusion dots in a predetermined pattern on the lower surface of the light guide plate. The diffusion dots have different areas depending on the distance from the light source of the light guide plate, thereby making it possible to obtain uniform brightness over the entire surface of the light guide plate as is well known.

In Patent Document 1, a light guide plate, a condenser, a reflector, and the like are used, and the number of parts is large. For this reason, in the backlight device and the liquid crystal display device using the backlight device, the component cost is high. In addition, since a fluorescent tube is used, power consumption is large.
In addition, the fluorescent tube has a heavy load on the global environment because mercury vapor is sealed inside. Therefore, the use tends to be prohibited in some areas such as Europe.

Therefore, LEDs (Light Emitting Diodes) have come to be used as an alternative light source for fluorescent tubes.
In a backlight device of a liquid crystal display device using an LED as a light source, an optical system that uses the entire liquid crystal display device from the LED as a surface light source is required. A backlight device used in a large-screen liquid crystal display device generally has a structure in which the backlight device is divided into a plurality of backlight blocks. The LEDs in each backlight block need to be able to receive light uniformly within the backlight block.

Moreover, although it changes with shapes of LED, generally, as for LED, the breadth of a horizontal direction (X direction) is larger than the breadth of a height direction (Z direction).
11A and 11B are diagrams illustrating light distribution characteristics of light emitted from a side-view type LED with respect to the distance of the backlight block. FIG. 11A is a schematic view showing the display surface field of the LED when viewed from above (the display surface of the liquid crystal display device), and FIG. 11B shows the display of the LED when viewed from the side (side surface of the liquid crystal display device). It is a schematic diagram which shows a surface visual field. Reference numeral 7 denotes an LED as a light source, 6 denotes an LED substrate on which the LED 7 is mounted, and 115 and 116 denote light source distributions showing light distribution characteristics. For example, as shown in the schematic view showing the display surface field of the LED when viewed from the side (side surface of the liquid crystal display device), the spread ∠W in the horizontal direction (X direction) is about 120 °, and the height direction The spread ∠H in the (Z direction) is about 90 °. Further, the LED 7 has a directivity characteristic that spreads in a spherical shape in front of the LED 7 (outgoing direction).

The LED has a light distribution characteristic as described in FIGS. 11A and 11B. The brightness of light decreases in inverse proportion to the square of the propagation distance. Therefore, when the luminance is measured on the surface of the liquid crystal panel, the luminance is different in each of the X direction and the Y direction. For this reason, the image quality is not uniform. In particular, in the Y direction, the region farthest from the LED 7 (the most advanced portion of the backlight block) is a dark region (see region 28 in FIGS. 8B, 9B, and 10B described later).

JP-A-6-174929

In view of the above problems, an object of the present invention is to reduce power consumption by using an LED, and to transmit light almost uniformly over the entire surface of a backlight block, so that the backlight device has uniform luminance. And providing a liquid crystal display device.

In order to achieve the above object, a backlight device of the present invention is a backlight device for irradiating light to a liquid crystal panel. The backlight device includes a chassis and a plurality of backlight blocks on the chassis. Each backlight block has a sheet-like reflecting member provided on the chassis on the bottom side of the backlight block, and is provided to face the reflecting member. A plate-like optical element disposed at a predetermined interval in a direction perpendicular to the light irradiation surface of the light source, and a direction parallel to the light irradiation surface of the backlight, disposed in a space between the optical element and the reflecting member A plurality of LEDs (LightＬＥＤEmitting Diodes) that emit light to the light, and the space between the plurality of LEDs in a direction parallel to the light irradiation surface and the light emitting direction. A partition plate that transmits light through the optical element while repeatedly reflecting and propagating light from the light source in the space between the optical element and the reflecting member, and guiding the light toward the liquid crystal panel. Is the first feature.

In the backlight device according to the first feature of the present invention, the second feature is that the LED is a side view type LED.

In the backlight device according to the first feature of the present invention, a third feature is that a predetermined pattern is formed on the optical member and / or the reflection sheet.

The backlight device according to the first aspect of the present invention is characterized in that the optical element directly above the LED is provided with a shielding plate for shielding light emitted above the LED.

In the backlight device according to the first aspect of the present invention, the partition plate is a partition plate that promotes the propagation of the LED, and supports the space between the chassis and the optical element. 5 features.

In the backlight device according to the first aspect of the present invention, the partition plate is a partition plate that promotes propagation of the LED, and the LED is the optical element between the chassis and the optical element. A sixth feature is that the space is attached so as not to contact and the space is supported.

In the backlight device according to the first aspect of the present invention, the partition plate is about ½ to ３ of the length of the backlight block in the light emitting direction from the light emitting port of the LED. A seventh feature is that the partition plate is not provided on the most distal end side of the backlight block.

In the backlight device according to the first feature of the present invention, the partition plate is configured by bending the chassis and the reflecting member, according to an eighth feature.

In order to achieve the above object, a liquid crystal display device according to the present invention uses a liquid crystal panel and the backlight device according to any one of the backlight devices according to the first to eighth features of the present invention. Is the ninth feature.

According to the present invention, it is possible to provide a backlight device capable of improving the utilization efficiency of light from a light source and obtaining a high-quality image, and a liquid crystal display device using the backlight device.

It is an exploded view showing the outline of the whole composition of the liquid crystal display which has the backlight device concerning the embodiment of the present invention. 1 is a cross-sectional view of a backlight device according to an embodiment of the present invention that is orthogonal to a light irradiation surface and parallel to an optical axis direction of an LED. It is sectional drawing of the liquid crystal display containing the internal structure and backlight block of a backlight block regarding embodiment of this invention. It is a schematic three-dimensional view of the backlight according to the embodiment of the present invention. It is sectional drawing orthogonal to the optical-axis direction of LED7 and a backlight light irradiation surface of the backlight apparatus which concerns on the Example of this invention, and its peripheral part. It is explanatory drawing which shows the example of formation of the pattern for producing the brightness brightness-and-darkness distribution from a liquid crystal display inside a backlight block according to a backlight block. It is the elements on larger scale of FIG. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is sectional drawing which looked at the liquid crystal display device from the side surface. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is a schematic diagram which shows the display surface visual field of LED at the time of seeing a liquid crystal display device from a display surface. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is sectional drawing which looked at the liquid crystal display device from the side surface. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is a schematic diagram which shows the display surface visual field of LED at the time of seeing a liquid crystal display device from a display surface. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is sectional drawing which looked at the liquid crystal display device from the side surface. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is sectional drawing which looked at the liquid crystal display device from the side surface. It is a figure which shows the light distribution characteristic of the light irradiated from side view type LED with respect to the distance of a backlight block, and is a schematic diagram which shows the display surface field of LED at the time of seeing from the top (display surface of a liquid crystal display device) is there. It is a figure which shows the light distribution characteristic of the light irradiated from side view type LED with respect to the distance of a backlight block, and is a schematic diagram which shows the display surface visual field of LED at the time of seeing from the side (side surface of a liquid crystal display device). . It is a figure which shows one Example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows one Example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows one Example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows one Example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED to the backlight apparatus in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED to the backlight apparatus in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED to the backlight apparatus in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED to the backlight apparatus in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED to the backlight apparatus in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows an example which has arrange | positioned LED to the backlight apparatus in the backlight apparatus which concerns on embodiment of this invention. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is sectional drawing which looked at the liquid crystal display device from the side surface. It is a figure which shows arrangement | positioning of LED of one Example of the liquid crystal display device of this invention, and is a schematic diagram which shows the display surface visual field of LED at the time of seeing a liquid crystal display device from a display surface. It is a figure which shows an example of the brightness | luminance evaluation result by the difference of Example 1 and Example 2. FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the following description is for describing one embodiment of the present invention, and does not limit the scope of the present invention. Accordingly, those skilled in the art can employ embodiments in which these elements or all of the elements are replaced with equivalent ones, and these embodiments are also included in the scope of the present invention.
In this document, components having common functions are denoted by the same reference numerals in the description of each drawing including those already described with reference to FIGS. 11A and 11B to avoid duplication of description as much as possible.

First, an overall configuration of a video display device to which the backlight device according to the present embodiment is applied will be described with reference to FIGS. 1 to 7, and thereafter, means for solving the problems of the present invention will be described. An embodiment will be described.

FIG. 1 is an exploded view showing an outline of the overall configuration of a liquid crystal display device having a backlight device according to an embodiment of the present invention, and FIG. 2 is orthogonal to the light irradiation surface of the backlight device according to the present embodiment. FIG. 3 is a cross-sectional view parallel to the optical axis direction of the LED, and FIG. 3 is a cross-sectional view of the internal configuration of the backlight block and a liquid crystal display including the backlight block according to this embodiment.

As shown in FIG. 1, a transmissive liquid crystal display device using a liquid crystal panel 1 that is widely used as a display for video display includes a liquid crystal panel 1, an optical element or a diffusion plate, and a diffusion sheet as an overall configuration. , An optical sheet unit 2 including a polarizing plate, a deflection film, and the like, and a backlight device 3. For example, as shown in FIG. 2, the backlight device 3 according to the present embodiment is formed by arranging a plurality of backlight blocks 4 in a matrix on a plane (in the direction of the light irradiation surface of the backlight device). In addition, uniform luminance is obtained in the large-sized backlight device 3. In the liquid crystal display, a backlight device 3 is necessary for irradiating light from the back side of the liquid crystal panel 1, and the backlight device 3 has a direct type, a side light (edge light) type, and a direct type depending on its structure. There is a hybrid system that combines a sidelight system with This hybrid system refers to a structure in which the backlight is optically divided into a plurality of backlight blocks and the light intensity is individually controlled, that is, the area can be controlled. The hybrid system is also called a slim block system. The backlight device 3 according to the embodiment of the present invention is intended for a slim block system, and particularly employs a side-view type light source and has a structure in which the backlight is divided into a plurality of backlight blocks 4. It is intended.

As shown in FIG. 2, the backlight device 3 according to the present embodiment is disposed on the back side of the liquid crystal panel 1 in order to irradiate the liquid crystal panel 1 with light, and at least in the horizontal direction (liquid crystal LED 7 having a light emission axis (optical axis) parallel to the panel surface or the light irradiation surface direction of the backlight device, reflection sheet 19 that is a reflection member that reflects light from LED 7, and reflection sheet 19. And a plate-like optical element 20 for guiding light from the LED 7 and the reflection sheet 19 to the liquid crystal panel 1 side, which is disposed at a predetermined distance from the reflection sheet 19. Here, it is assumed that the LED 7 is a side-view type LED that emits light in a direction parallel to the electrode surface. The reflection sheet 19 is provided on a chassis (described later) located on the bottom side of the backlight device 3. The LED 7 is mounted on an LED substrate 6 that is a light source substrate.

As shown in FIG. 2, the backlight device 3 includes, for example, one LED 7 (actually a plurality of LEDs 7 arranged in the depth direction on the paper surface) in a direction orthogonal to the light irradiation surface and parallel to the optical axis of the LED 7. ) And the optical element 20 between the LEDs 7, the reflection sheet 19, and the space between them, is a single backlight block 4. Then, the amount of light or the light intensity can be controlled for each backlight block 4 by individually controlling the LEDs 7 corresponding to the backlight blocks 4. That is, in this embodiment, the area control (local dimming) is made possible by configuring as described above.

The optical element 20 is, for example, a diffusion plate, a transparent acrylic plate, a mirror plate, a diffusion plate with a fine pattern, an optical sheet, an optical property control plate, a polarization sorting plate, or the like. A sheet-like light control member 9 for controlling or adjusting the amount of light supplied to the optical element 20 according to the position of the optical element 20 is provided on the back surface of the optical element 20. In the example of FIG. 2, the light control member 9 is provided on the back surface of the optical element 20, but may be provided on the front surface of the optical element 20 or on both the back surface and the front surface. The light control member 9 has a predetermined light control function. The function includes, for example, two-dimensional reflection, transmission, diffusion, shading, absorption, re-emission, coloring, wavelength conversion, and a predetermined amount of light. It shall have at least two or more of the polarizing functions.

Thereby, the light control member 9 transmits part of the incident light, and is emitted from the optical element 20 as scattered light on the spot. In addition, a part of the incident light is reflected by the light control member 9 and propagates in the space in the optical axis direction of the LED 7 in cooperation with the reflection function by the reflection sheet 19 to guide the light far from the LED 7. Let That is, the light control member 9 reflects part of the light from the LED 7 and the light reflected by the reflecting sheet 19 while reflecting part of the light, and repeatedly performing this along the optical axis direction, thereby the backlight block. The light is sufficiently supplied to the tip of 4 (the part on the side opposite to the position of the LED 7). Thereby, regardless of the size of the backlight block 4, it is possible to improve the uniform luminance distribution and the light use efficiency. The light control member 9 is provided with slits and patterns in order to realize the transmission and reflection of the light.

The optical element 20 and the light control member 9, particularly the light control member 9, are separated from the LED 7 in the optical axis direction of the LED 7, the size or shape of the slit or pattern, or the light transmittance, reflectance, diffusivity, Optical functions such as the degree of capture, propagation rate, polarization transmittance, color transmittance, and spectral characteristics are changing. By doing in this way, the uniformity in the backlight block 4 is easily realizable.

Here, when the distance between the optical element 20 and the reflection sheet 19 (that is, the height of the space) is h, and the height of the LED 7 is Lh, the relationship between the distance h and the height Lh is 5Lh>h> 1. .2Lh is preferable. In this way, the light leaking from the upper surface of the LED 7 and the hot spot (the portion where the light is locally brightened) generated in the vicinity of the light emitting portion of the LED 7 are expanded by the COS ⁴ angle (fourth power law) in the space of the distance h. It becomes possible to diffuse and make it difficult to see as unevenness. The above condition can be said to be a distance necessary for dimming the light transmitted directly from the LED 7 through the light control member 9 because the side-view type LED 7 and the light control member 9 are too close.

FIG. 3 is a schematic three-dimensional view of the backlight according to the present embodiment. The LEDs 7 are arranged together with a substrate (not shown) in the horizontal direction of the liquid crystal panel in a metal chassis 11 made of, for example, aluminum. The optical element 20 is arranged with a predetermined distance from the LED 7. The optical element 20 can be made of a material such as a general diffusion plate used in a fluorescent tube type backlight device such as CCFL. Thereby, the slim block type backlight device 3 can be realized at low cost.

Further, an optical sheet group 18 such as a prism sheet or a brightness enhancement film is disposed on the optical element 20 to reduce luminance unevenness on the entire backlight irradiation surface. In FIG. 3, the optical sheet group 18 includes a plurality of optical sheets, but only one optical sheet group may be provided.

In FIG. 3, a dotted line is drawn on the optical element 20, which is drawn to virtually divide the backlight block 4, and the backlight block 4 is actually physically separated. In addition, a groove or the like for dividing the backlight block 4 is not provided. In this embodiment, it is assumed that the optical element 20 is composed of one plate-like member (diffuser plate). If necessary, a groove or the like for dividing the backlight block 4 may be provided on the front surface (liquid crystal panel side) or the back surface (chassis 11 side) of the optical element 20.

FIG. 4 shows a schematic top view and a cross-sectional view of the backlight device according to this embodiment. In the example of FIG. 4, patterns 101, 102, and 103 having a predetermined shape are provided on the front surface and / or the back surface of the light control member 9 or the optical element 20. These patterns 101 to 103 show the case of viewing from the liquid crystal panel 1 side. 4 indicates the width of one backlight block (dimension in the direction orthogonal to the optical axis direction of the LED 7). That is, in this example, six LEDs 7 are provided in the backlight block. Of course, the number of LEDs 7 per backlight block is not limited to this.

As shown in the figure, the pitch, density, or shape of the patterns 101 to 103 in the optical axis direction (left and right direction of the paper) of the LED 7 is changed according to the distance from the LED 7. On the other hand, the pitch, density, or shape of the patterns 101 to 103 in the direction perpendicular to the optical axis of the LED 7 (up and down in the drawing) is substantially the same. More specifically, the patterns 101 to 103 are formed to extend in the optical axis direction from the side opposite to the light emitting direction (optical axis direction) of the LED 7. The patterns 101 to 103 change in accordance with the distance in the optical axis direction from the LED 7. For example, as the distance in the optical axis direction from the LED 7 increases as in the pattern 101, the patterns 101 to 103 may have a tapered shape. The shape may be a combination of an ellipse whose major axis is the optical axis direction of the LED 7 as in 102 and an ellipse in a direction orthogonal to the optical axis direction, or in the optical axis direction from the light source 7 as in the pattern 103. It is good also as a shape which spreads, so that distance becomes large.

The patterns 101 to 103 are basically provided on the back surface of the optical element 20, but may be provided on the surface of the optical element 20. Further, as patterns 101 to 103, a printed sheet, a thermal transfer sheet, a perforated reflection / transmission sheet, a reflection sheet with a pattern, or a pattern printed on an optical sheet is placed near the LED 7 on the back surface or the front surface of the optical element 20 or both. The patterns 101 to 103 may be mounted.

As the patterns 101 to 103, any shape or member may be adopted as long as it can control or adjust the light action, light transmission, reflection, propagation rate and the like according to the position (distance from the LED 7). it can. For example, by gradually reducing the pattern density as it moves away from the LED 7 in the optical axis direction, the vicinity of the LED 7 increases light emission and reflection to reduce the transmitted light to 10% or less, while the distance away from the LED 7 transmits the transmitted light. Do more. As a result, not only the light traveling from the LED 7 in the optical axis direction but also the two-dimensionally (radially) propagating light is increased, and the amount of light emitted toward the liquid crystal panel is increased according to the distance from the LED 7. be able to. And according to such a structure, the brightness nonuniformity of the optical axis direction of LED7 can be reduced, and the brightness uniformity in a backlight block and a backlight irradiation surface front surface can be improved.

The patterns 101 to 103 can be composed of a collection of minute dots as shown in FIG. 4, and the outer shape of the dot assembly is polka dots, curves, dotted lines, radial straight lines, radial curves, etc. Various shapes can be used. In the dot aggregate, if the dot density is changed so that the dot density gradually gradations the distance from the LED 7, the error sensitivity due to the positional deviation between the LED 7 and the pattern can be improved.

In addition, when the pattern is formed by printing, the ink film thickness, ink color (mixing blue and black colors, controlling the transmittance and applying gradation), dot size, dot shape, pattern just above the LED The shape and the printing thickness can be easily adjusted, and the above-described outer shape of the dot aggregate and gradation can be formed more satisfactorily. Therefore, when the pattern is formed by printing, the luminance uniformity can be further improved.

Here, as shown in FIG. 4, the size of the pattern in the direction perpendicular to the optical axis of the LED 7 and parallel to the light emitting surface of the optical element 20 or the back surface thereof (up and down direction on the paper surface). When (dimension) is a, the longitudinal size of the light emitting surface 71 of the LED 7 is c (see FIG. 15), and the arrangement pitch of the LEDs 7 is p, the condition of p ≧ a ≧ c is satisfied. Further, when the pitch of the pattern is e, the condition of p ≧ a ≧ 0.5 × e is satisfied. Furthermore, the relationship between the distance h and the dimension a of the pattern satisfies the condition h ≧ a. Furthermore, another pattern 104 is provided at a position corresponding to between two adjacent light sources of the optical element 20, and the transmittance T of the other pattern satisfies the condition of 0.1% ≦ T <50%. I am doing so.

FIG. 5 shows a cross-sectional view of the backlight device according to the present embodiment and the peripheral portion thereof orthogonal to the optical axis direction of the LED 7 and the backlight light irradiation surface.

As shown in the figure, a signal control board 15, an LED drive circuit 16, and a power source 14 are arranged between a back cover 17 that is a rear casing of the liquid crystal display device and the chassis 11. The signal control board 15, the LED drive circuit 16, and the power supply 14 are attached to the chassis 11. The chassis 11 may be one to which the above-described reflection sheet 19 is attached. In addition, the chassis 11 having the reflection sheet 19 attached thereto is pressed to form a curved surface or an inclined surface along the optical axis direction of the LED 7 so that the reflection angle of the light on the reflection sheet surface 19 can be reduced. It can be varied along the axial direction. Thereby, it is easy to propagate the light from the LED 7 in the optical axis direction, and there is an effect of increasing the amount of light supplied to the front end portion of the backlight block 4 (the portion opposite to the position of the LED 7). Moreover, since a diaphragm is added to the chassis 11, the mechanical strength of the chassis 11 is also increased.

The space between the reflection sheet 19 and the light control member 9 is held by a conical pin mold 38 to ensure a predetermined distance. Accordingly, light is gradually emitted by the optical control member 9 and the optical element 20 while propagating through the backlight block 4, and overall uniform light can be controlled in units of backlight blocks.

Referring back to FIG. 2, the backlight device 3 according to the present embodiment basically has an LED 7 as a light source installed on the LED substrate 6 and a light for effectively guiding the light from the LED 7 to the liquid crystal panel 1. An optical element 20, a reflective sheet 19 for supplying light to the optical element 20, and a space between the optical element 20 and the reflective sheet 19 for favorably propagating light in the optical axis direction of the LED 7 are provided. ing. A light control member 9 is provided on the back surface of the optical element 20 provided on the liquid crystal panel 1 side of the space, thereby gradually emitting light from the LED 7 along the optical axis direction of the LED 7, and a backlight block 4 uniform light distribution is realized.

Here, in the configuration example shown in FIG. 2, the backlight block 4 is formed in a rectangular shape when viewed from the light irradiation surface side of the backlight device 3, and its longitudinal direction (from left to right on the paper surface in FIG. 3). ), The light from the LED 7 advances, is reflected by the back surface (the reflection sheet 19 side) of the backlight block 4, and the light advances to the liquid crystal panel 1. A plurality of LEDs 7 are arranged at appropriate intervals on the short side of the backlight block 4 (in the vertical direction of the paper in FIG. 3). The LEDs 7 may be arranged on the long side of the backlight block 4.

Next, a technique for reducing the brightness difference between the brightness of the boundary of the backlight block and the brightness inside the backlight block in the backlight device according to the present embodiment, and making the brightness from the boundary inconspicuous is shown in FIGS. This will be described with reference to FIG. Here, FIG. 6 shows an image of a space in which the backlight block 4 is connected in the optical axis direction of the LED 7 and the direction orthogonal to the optical axis direction. Here, for simplicity of illustration, the backlight block 4 having only one row and one column is shown.

FIG. 6 is a diagram for explaining an example of pattern formation for intentionally generating the brightness / darkness distribution from the backlight device according to the present embodiment over a plurality of backlight blocks, and FIG. It is a figure explaining the situation where a luminance difference arises between the boundary of a backlight block, and the inside of a backlight block by arranging a plurality of backlight blocks. The pattern in this embodiment is called a “bright / dark pattern”. In the drawing, the light / dark pattern includes a bright brightness portion 40, a dark brightness portion 41, and a bright / light brightness portion 42. Here, the brightness difference (brightness / darkness difference or brightness unevenness) is obtained by viewing the light emitted from the backlight device 3 from the light emitting side of the optical sheet group 18 (see FIG. 2) including the diffusion plate and the like. It is assumed that the brightness difference is. Here, the pattern of the brightness bright portion 40 is a pattern that has a larger effect of diffusing light than the brightness dark portion 41 and the brightness mid-light portion 42 (that is, the roughness (the density of fine irregularities) is high), The pattern of the portion 42 is a pattern that has a larger effect of diffusing light than the luminance dark portion 41.

As described above, when the backlight device 3 is configured by arranging a plurality of backlight blocks 4 vertically and horizontally, light leaks from the boundary of the backlight block 4 or directly above the LEDs 7 to generate bright lines and hot spots. The resulting bright brightness portion occurs. On the contrary, there may be a case where light is insufficient at the boundary of the backlight block or on the back side of the LED 7 to become a dark line.
Therefore, in this example, the light emitted from the light source (LED 7) is uniformly emitted (in the vertical front direction in the drawing) inside the backlight block 4, that is, the luminance of the optical element 20 is uniform. Optical patterns such as 40, 41 and 42 in the figure are arranged on the back surface and / or the front surface or in the vicinity of the back surface. FIG. 6 illustrates a pattern arranged on the back surface. The density of the pattern is appropriately adjusted according to the optical axis direction from the light incident portion of the LED 7 so that the luminance distribution becomes uniform. In the case of FIG. 6, a pattern is arranged in which the density of the light incident part is slightly high, the central part is slightly low, and the tip part has the highest density. The graph shown in the lower part of FIG. 6 shows the density of the light and dark pattern corresponding to the position of the optical element 20. This light / dark pattern is formed on the back surface of the optical element 20 composed of a diffusing plate, a clear plate, an optical film attaching plate material, a polarizing member, etc., on a diffusing concave / convex surface, concave microlens, convex microlens, prism, truncated cone, cone or It is formed by adding a print pattern or the like. Instead of this, an optical functional film having one or more functions such as light reflection, light shielding, transmission and propagation is provided with a notch, a slit, a circular hole, an elliptical hole, a predetermined shape hole, or a shading process. It may be formed by applying fine processing, fine work, printing pattern, or the like. Thereby, the luminance distribution of the emitted light from the optical element 20 can be freely controlled.

In the backlight device according to the present embodiment, a luminance difference is intentionally formed inside the backlight block, and the luminance unevenness extends as a whole, thereby causing a linear or grid-like shape at the boundary of the backlight block. It is characterized in that a bright (or dark) luminance portion is relaxed, that is, it is difficult to visually recognize. In the example shown in FIG. 6, the luminance dark portion 41 and the luminance middle light / dark portion 42 (a portion that is slightly darker than the luminance bright portion 40 but brighter than the luminance dark portion 41) are alternately arranged in the backlight block 4. It is a structural example. That is, the brightness difference between the backlight block 4 and the brightness bright portion at the boundary of the backlight block 4 is reduced by providing a brightness difference between the brightness and darkness inside the backlight block 4.

When dark lines are generated at the boundary, in order to make the dark lines inconspicuous, it is darker than the uniform luminance surface of the backlight block so as to form a luminance contrast between the backlight block 4 and the dark line. May be provided with a bright pattern.

Further, as shown in FIG. 7, this light-dark pattern has a rectangular shape, and squares are arranged on a staggered pattern. At this time, from the LED 7 to the front end portion of the backlight block 4, the arrangement pitch of the rectangular light portions is gradually narrowed so that the density is increased or arranged. That is, the light is emitted more efficiently as it goes to the tip portion, and the uniformity within the block is enhanced. At the same time, an unusual pattern may be provided in a portion where the luminance changes extremely, such as a bright line or a dark line in the vicinity or boundary of the LED 7, or the size of a circular or elliptical pattern may be changed. With the optimized size and shape pattern, the function of improving the brightness uniformity and the function of making the brightness difference inconspicuous are compatible. Thereby, the light control unit 9 can gradually select the light propagating through the space, take it into the optical element 20, and control the light emitted to the liquid crystal panel 1 side.

By providing a difference in brightness between the backlight block 4 and the brightness unevenness including the boundary in the entire backlight 3, the brightness bright portion at the boundary of the backlight block 4 is provided. Becomes difficult to see. Further, a light shielding member composed of a light shielding sheet, light shielding printing or the like is installed at a position corresponding to the LED 7 together with the light control member 9 to shield the direct light of the LED 7 and partially transmit, reflect, or propagate the light. Prevents spots from forming. At this time, even if light leaks from the LED 7 slightly due to the thinness of the reflection sheet, the light is diffused by the light and darkness of the staggered pattern and becomes inconspicuous.

The brightness difference described above can be realized not only by the optical element 20 and the light control member 9 but also by forming a pattern on the reflection sheet 19 and the optical sheet group 18.

In addition, although not shown, an elliptical medium brightness portion may be formed inside the backlight block 4. The bright, medium and dark portions of luminance are formed on the surface of the optical element 20 by a so-called rough surface (rough surface) such as a fine or dense uneven surface. A plurality of the oval rough surfaces are arranged in a direction parallel to the arrangement direction of the LEDs 7 of the optical elements (in this example, the short direction of the optical element 20) to form one luminance mid-bright and dark area. Are provided in a direction perpendicular to the arrangement direction of the LEDs 7 (in this example, the short longitudinal direction of the optical element 20). As a result, the rough surface functions to increase the amount of light traveling forward than the surrounding surface, thereby producing bright brightness.

Looking at the entire backlight device 3 including the boundary of the backlight block 4, the presence or absence of a light / dark part in the brightness causes variations or irregularities in the brightness / darkness distribution emitted forward from the backlight device 3, It becomes difficult to visually recognize the brightness level of the brightness (brightness of the boundary becomes inconspicuous). The shape is not limited to an elliptical shape, and may be a circular shape, a rectangular shape, or a circular shape, and the number of adjacent bright, middle, light, and dark portions (for example, the number in the vertical direction on the paper) is changed to two or three. May be. In short, it is only necessary to form the mid-bright and dark portions so that irregularities in the luminance difference occur with the dark portions.

In the above embodiment, an element for providing a bright portion on the surface of the optical element 20 (diffuser plate) such as the rough surface (rough surface), uneven surface, prism surface, concave lens or convex lens (hereinafter referred to as “bright portion providing element”). Is formed so as to extend in the direction parallel to the arrangement direction of the LEDs 7 (in this embodiment, the short direction of the optical element) on the surface of the diffusion plate, and the bright portion imparting element is arranged in the LED arrangement direction. Two or more are arranged in a direction orthogonal to the direction (in this embodiment, the short direction of the optical element 20 and the traveling direction of light from the LED in the optical element 20). With this configuration, it is possible to generate a luminance difference (luminance unevenness) with a period shorter than the period of the luminance bright portion (or luminance dark portion) at the boundary portion of the backlight block 4 on the surface of the optical element 20. Therefore, it is difficult to visually recognize bright portions (or dark portions) in the boundary portion of the backlight block 4.

The distance between the maximum points of each luminance in the two or more bright part providing elements is preferably about 0.5 to 3 cm, and the distance between the maximum points is incident on the optical sheet group from the surface of the diffusion plate. It is preferably at least twice the distance to the surface (incident surface of the diffusion plate arranged at the position closest to the diffusion plate). Further, the luminance difference between the light passing through the bright portion providing element and the light emitted from the portion other than the bright portion providing element on the surface of the diffuser plate is diffused from the bright bright portion (or the dark luminance portion) at the boundary portion of the backlight block 4. More preferably, it is 50% or more of the luminance difference of light emitted from a portion other than the bright portion providing element on the plate surface. If the bright portion providing element is formed so as to satisfy these conditions, the bright luminance portion (or the dark luminance portion) at the boundary portion of the backlight block 4 can be made inconspicuous.

Moreover, if the element for diffusing the light is provided in the direction orthogonal to the arrangement direction of the LEDs 7 on the surface of the diffusion plate, the backlight block generated in the direction orthogonal to the arrangement direction of the LEDs 7 (left and right direction in FIG. 2) It is difficult to visually recognize bright portions (or dark portions) at the boundary of 4. Of course, you may provide the element for diffusing the said light in both the direction orthogonal to the direction parallel to the sequence direction of LED7.

According to the configuration of the above embodiment, it is possible to make the bright luminance portion or the dark luminance portion between the boundaries of the backlight block 4 inconspicuous. Similarly, it is possible to make the darkness portion inconspicuous.

However, even in the case of the embodiment shown in FIGS. 1 to 7, the light emitted from the LED 7 has the light distribution characteristics as described in FIGS. 11A and 11B. Therefore, there is a possibility that the luminance uniformity is insufficient in the area close to and far from the LED in the backlight block.

The first embodiment of the present invention will be further described with reference to FIGS. 8A and 8B. 8A and 8B are diagrams showing the arrangement of LEDs in one embodiment of the liquid crystal display device of the present invention. For example, FIGS. 8A and 8B are diagrams showing an embodiment in which the LEDs 7 having the light distribution characteristics shown in FIGS. 11A and 11B are arranged in a liquid crystal display device. FIG. 8A shows a cross-sectional view of the liquid crystal display device as viewed from the side, and FIG. 8B is a schematic diagram showing the display surface field of the LED when the liquid crystal display device is seen from the display surface. However, the LED substrate 6 is not shown in FIG. 8B.
As shown in FIG. 8A, the liquid crystal display device includes a liquid crystal panel 1, an optical sheet unit 2 including a diffusion plate, a diffusion sheet, a polarizing plate, a deflection film, and the like as a whole configuration, and a backlight device. . The backlight device is formed by, for example, arranging a plurality of backlight blocks 4 in a matrix on a plane (in the direction of the light irradiation surface of the backlight device), and obtains uniform luminance in a large-sized backlight device. I am doing so.
8A and 8B, one backlight block 4 is composed of nine LEDs 7 (only a part is shown in FIGS. 8A and 8B). For example, the length pp of the backlight block in the Y direction from the exit of the LED 7 is 95 mm, the width w in the X direction of the LED 7 is 4.9 mm, and the distance d between the LEDs 7 is 28.0 mm.

In the liquid crystal display device of FIGS. 8A and 8B, a backlight device is required to irradiate light from the back side of the liquid crystal panel 1 (below the Z direction in FIGS. 8A and 8B). The backlight device of FIGS. 8A and 8B is a hybrid backlight device depending on its structure. This hybrid system indicates a structure in which the backlight device is optically divided into a plurality of backlight blocks 4 so that the light intensity can be individually controlled, that is, the area can be controlled. The hybrid system is also called a slim block system. The backlight device according to the present invention is intended for a slim block system, and particularly for a structure in which a side view type LED is used as a light source and the backlight device is divided into a plurality of backlight blocks. To do.

8A and 8B, the LED 7 emits diffusive light into the air layer 24 in the direction of the arrow 27. The emitted light propagates in the air layer 24 while being repeatedly reflected between the reflection sheet 19 and the diffusion plate (optical sheet portion 2). The propagating light passes through the optical sheet portion 2 such as a diffusion plate and is emitted in the direction of the liquid crystal panel 1.
However, the LED 7 has a light distribution characteristic as described in FIGS. 11A and 11B. The brightness of light decreases in inverse proportion to the square of the propagation distance. Therefore, when the luminance is measured on the surface of the liquid crystal panel 1, the luminance is different at the points A, B, and C. Thus, the image quality is not uniform. In particular, the region (the most advanced portion of the backlight block) 28 farthest from the LED 7 that is the light source is a dark region.
Therefore, in a second embodiment described below, a backlight device and a liquid crystal display device that further improve the utilization efficiency of light from the light source and obtain a high-quality image will be described with reference to FIGS. 9A and 9B.

9A and 9B are diagrams showing the arrangement of LEDs in an embodiment of the liquid crystal display device of the present invention. For example, FIG. 9A and FIG. 9B are provided with a partition plate 91 parallel to the emission direction 27 of the LED 7 in the embodiment of FIG. 8A and FIG. 8B. As described with reference to FIG. 11A, the emitted light of the LED 7 spreads in the lateral (X) direction, but is reflected by the partition plate 91 and the propagation of the LED 7 in the emitting direction 27 is promoted. As a result, the amount of light that can be emitted from the LED 7 can reach the most distal portion 28 as compared with the configuration of FIGS. 8A and 8B. For this reason, light can be propagated substantially uniformly over the entire X direction and Y direction of the backlight block 4. In particular, the luminance in the Y direction becomes uniform. Accordingly, the output light from the liquid crystal panel 1 has a more uniform brightness than that of the first embodiment. Therefore, it is possible to realize a backlight device capable of improving the utilization efficiency of light from the light source and obtaining a high-quality image and a liquid crystal display device using the backlight device. Here, the partition plate 91 is flat, for example, and has a surface structure that totally reflects light in the same manner as the reflection sheet 19.
In addition, in Example 2 of FIG. 9A and FIG. 9B, the partition plate 91 is partitioned for every three LEDs. However, the number of LEDs provided with a partition plate is arbitrary, such as one by one or four by one. Further, the partition plate may not be provided on the outermost periphery of the backlight device.
Further, the partition plate 91 is fixed with a resin push rivet such as nylon (registered trademark), for example, with a through-hole formed in a point of the reflection sheet 19 and the chassis 11.
Furthermore, the partition plate is arranged from the exit of the LED 7 to a distance of about ½ to ３ of the length pp of the backlight block in the Y direction, and no partition plate is provided on the most distal end side.

FIG. 17 shows the results of luminance evaluation results measured at points A, B, and C, assuming that the output of LED 7 is the same when there is a difference between Example 1 (without a partition plate) and Example 2 (with a partition plate). It is a figure which shows an example.
In the case where the partition plate of Example 1 was not provided, the point A was 140 cd / m ² , the point B was 70 cd / m ² , and the point C was 65 cd / m ² . When the partition plate was provided as in Example 2, the point A was 140 cd / m ² , the point B was 88 cd / m ² , and the point C was 83 cd / m ² .
Thus, in Example 2 (with a partition plate), the difference in luminance measured at points A, B, and C is small compared to Example 1 (without a partition plate), as shown in FIG. I understand that.

A third embodiment of the present invention will be described with reference to FIGS. 10A and 10B. 10A and 10B are diagrams showing the arrangement of LEDs in one embodiment of the liquid crystal display device of the present invention. For example, in FIGS. 10A and 10B, in Example 2 of FIGS. 9A and 9B, a light-blocking sheet 92 that blocks light is further provided immediately above the LED 7 (however, since it becomes complicated, some It is only shown on the LED.)
As a result, the light emitted from the liquid crystal panel 1 does not have an extreme luminance in the immediate vicinity of the LED 7, and the light from the liquid crystal panel 1 has a uniform luminance as compared with the second embodiment. Therefore, it is possible to realize a backlight device capable of improving the utilization efficiency of light from the light source and obtaining a high-quality image and a liquid crystal display device using the backlight device.
The light shielding sheet 92 is formed on the optical sheet portion 2 by printing. Alternatively, a separate light shielding sheet may be created and attached to the optical sheet portion 2 with a double-sided tape or the like.
Furthermore, although the shape of the light shielding sheet 92 is an ellipse in FIGS. 10A and 10B, it is obvious that the shape is not limited to this shape. Moreover, it may be a continuous sheet without being divided for each LED.

A fourth embodiment of the present invention will be described with reference to FIGS. 12A, 12B, 12C, and 12D. In Example 2 to Example 3, the partition plate 91 was plate-shaped. However, as shown in FIG. 12A, the cross section may be an isosceles triangle with the liquid crystal panel 1 side at the top. Moreover, as shown in FIG. 12B, the cross section may be a straight line or a curved shape that bends at one or a plurality of locations. Furthermore, as shown in FIG. 12C, the cross section may have a curved shape that gradually spreads toward the reflection sheet 19 with the liquid crystal panel 1 side as the top. The light from the liquid crystal panel 1 has a more uniform luminance than in the second to third embodiments. Furthermore, as shown in FIG. 12D, in the shape of FIG. 12A, at least one of the LED 7 side or the most distal portion of the backlight block may be inclined. Further, the diagonal line may be a straight line, a curved line, or a sawtooth shape.
As a result, it is possible to realize a backlight device capable of improving the utilization efficiency of light from the light source and obtaining a high-quality image, and a liquid crystal display device using the backlight device. In addition, since the partition plate is linear when viewed from the liquid crystal panel 1, it is difficult for the viewer to understand the partition plate that is not visually recognized (intrusive to the image displayed on the liquid crystal panel 1). Suitable for the device.

In addition to the shapes of FIGS. 12A, 12B, 12C, and 12D, the shape of the partition plate is such that the LED 7 side is cut obliquely as shown in FIGS. 13A, 13B, and 13C. Fig. 13A corresponds to Fig. 12A, Fig. 13B corresponds to Fig. 12B, and Fig. 13C corresponds to Fig. 12C.) The light emitted from the LED 7 is not reflected and returned to the LED 7 side. The projected light is projected onto the backlight block.
As a result, the light from the liquid crystal panel 1 has a more uniform luminance than in the second to third embodiments. Therefore, it is possible to realize a backlight device capable of improving the utilization efficiency of light from the light source and obtaining a high-quality image and a liquid crystal display device using the backlight device. Furthermore, since the partition plate is linear when viewed from the liquid crystal panel 1, the partition plate that is not visually recognized becomes more difficult for the viewer to understand than the embodiments shown in FIGS. 12A, 12B, 12C, and 12D. It is suitable for a backlight device and a liquid crystal display device.

In addition to the shapes of FIG. 12A, FIG. 12B, FIG. 12C and FIG. 12D or FIG. 13A, FIG. 13B and FIG. 13C, the partition plate has one or more liquid crystal panels 1 as shown in FIG. You may make it have a sharp protrusion. The shape of the protrusion, the interval, and a combination thereof are arbitrary.
14A to 14F are preferably formed so that their tops become dots. As a result, since the partition plate is dotted as viewed from the liquid crystal panel 1, the partition plate that is not visually recognized becomes more difficult for the viewer to understand than the embodiment shown in FIGS. 13A, 13B, and 13C. And suitable for a liquid crystal display device. Furthermore, the viewer's difficulty in understanding is more effective as the positions of the points become irregular. For this reason, preferably, as shown in FIGS. 14E and 14F, the arrangement of the protrusions may be irregular.

A fifth embodiment of the present invention will be described with reference to FIG. FIG. 15 is a diagram showing the arrangement of LEDs in one embodiment of the liquid crystal display device of the present invention. FIG. 15 shows a case in which the partition plate is not provided and the chassis 11 is bent to replace the partition plate as compared with the second to fourth embodiments.
In the embodiment of FIG. 15, the reflection sheet 19 is bent together with the chassis 11. Therefore, the light emitted from the LED 7 and directed in the lateral (X) direction is totally reflected by the reflection sheet portion that is bent and forms a partition.
As a result, similar to the second to fourth embodiments, the propagation of the LED 7 in the emission direction (depth direction on the paper surface) 27 is promoted. As a result, the amount of light that can be emitted from the LED 7 can reach the most distal portion 28 as compared with the configuration of FIGS. 8A and 8B. For this reason, light can be propagated substantially uniformly over the entire X direction and Y direction of the backlight block 4. In particular, the luminance in the Y direction becomes uniform. Accordingly, the output light from the liquid crystal panel 1 has a more uniform brightness than that of the first embodiment. Therefore, it is possible to realize a backlight device capable of improving the utilization efficiency of light from the light source and obtaining a high-quality image and a liquid crystal display device using the backlight device.

A sixth embodiment of the present invention will be described with reference to FIGS. 16A and 16B. 16A and 16B are diagrams showing the arrangement of LEDs in one embodiment of the liquid crystal display device of the present invention. For example, in FIGS. 16A and 16B, the partition plate 91 ′ is provided so as to be in contact with the back surface of the diffusion plate of the optical sheet portion 2 as compared with the third embodiment of FIGS. 10A and 10B. As a result, a support member such as a conical pin mold 38 for supporting the space between the reflection sheet 19 and the light control member 9 shown in FIG.
Thus, by providing the partition plate 91 ′, a supporting member for supporting the space between the reflection sheet 19 and the light control member 9 is not required in the first to fifth embodiments, and the component cost is reduced. In addition, the assembly cost can be reduced.

According to the first to sixth embodiments described above, it is possible to provide a backlight device capable of improving the utilization efficiency of light from the LED light source and obtaining a high-quality image, and a liquid crystal display device using the backlight device. it can.

1: liquid crystal panel, 2: optical sheet part, 3: backlight device, 4: backlight block, 6: LED board, 7: LED, 9: light control member, 11: chassis, 14: power supply, 15: signal control Substrate, 16: LED drive circuit, 17: Back cover, 18: Optical sheet group, 19: Reflective sheet, 20: Optical element, 22: Diffuser, 23: Optical member, 24: Air layer, 27: Emission direction, 28 : Cutting edge part, 38: Pin mold, 40: Brightness light part, 41: Brightness dark part, 42: Brightness light and dark part, 91, 91 ': Partition plate, 101, 102, 103, 104: Pattern, 115, 116: Light source distribution.

Claims (9)

1. In the backlight device for irradiating the liquid crystal panel with light,
   The backlight device has a chassis and a plurality of backlight blocks on the chassis,
   Each backlight block is provided on the bottom surface side of the backlight block and on the chassis, and is provided to face the reflecting member. The light irradiation of the backlight is performed from the reflecting member. A plate-like optical element disposed at a predetermined interval in a direction perpendicular to the surface, and light in a direction parallel to the light irradiation surface of the backlight disposed in a space between the optical element and the reflecting member. A plurality of LEDs (Light Emitting Diodes) to be emitted, and a partition plate that partitions the space in a direction parallel to the light emitting surface and the direction of emitting the light, between the plurality of LEDs.
   A backlight device characterized in that the light from the light source is transmitted through the optical element while being repeatedly reflected and propagated in the space between the optical element and the reflecting member, and guided to the liquid crystal panel side. .
2. 2. The backlight device according to claim 1, wherein the LED is a side view type LED.
3. 2. The backlight device according to claim 1, wherein a predetermined pattern is formed on the optical member and / or the reflection sheet.
4. 2. The backlight device according to claim 1, wherein a shielding plate for shielding light emitted above the LED is provided on the optical element immediately above the LED.
5. 2. The backlight device according to claim 1, wherein the partition plate is a partition plate that promotes the propagation of the LED, and supports the space between the chassis and the optical element. apparatus.
6. 2. The backlight device according to claim 1, wherein the partition plate is a partition plate that promotes propagation of the LED, and the LED does not contact the optical element between the chassis and the optical element. A backlight device mounted and supporting the space.
7. 2. The backlight device according to claim 1, wherein the partition plate is disposed from the light emission port of the LED to a distance of about ½ to の of the length of the backlight block in the light emission direction. The backlight device is characterized in that no partition plate is provided on the most distal portion side of the backlight block.
8. 2. The backlight device according to claim 1, wherein the partition plate is formed by bending the chassis and the reflecting member.
9. A liquid crystal display device using the liquid crystal panel and the backlight device according to any one of claims 1 to 8.

Images