JP2005019420A - Backlight device and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that the light irradiated from a light source penetrates through the holes formed on a reflection plate, and transmitted to the other side of the reflection plate opposite to the light source side. <P>SOLUTION: The light irradiated from the light source is prevented from penetrating through the holes formed on the reflection plate and being transmitted to the other side of the reflection plate opposite to the light source side, by forming at least a part of a light source supporting device with a light transmission prevention means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a device that supports a light source, and is used, for example, in a backlight device of a liquid crystal display device.

  In recent years, very large liquid crystal display devices have been developed. In such a large liquid crystal display device, a backlight having a fluorescent tube arranged in parallel with the liquid crystal panel is used.

  In order to form a large-sized liquid crystal display device, the length of the fluorescent tube used for the backlight must inevitably be increased. Fluorescent tubes have been used as light sources. For this reason, if the fluorescent tubes arranged in parallel are only supported at both ends, there is a problem that the support strength of the fluorescent tubes is not sufficient and deformation or breakage occurs.

  Therefore, in order to improve the support strength of the fluorescent tube, a light source support device that supports the intermediate portion of the fluorescent tube is required. Examples of the light source support device include those described in Patent Document 1. The technique described in this publication will be described with reference to FIG.

  FIG. 12 is a mounting view of the light source support device 50 described in the above publication. In FIG. 12, the light source support device 50 includes a support portion 52 having a partially-circular grip shape having an opening in a part for holding the periphery of the circular cross section of the light source 51, and a through hole 55 provided in the reflection plate 54. And a locking portion 53 that supports the light source support device 50 to the reflection plate 54.

Further, the light source support device 50 is made of a transparent material having flexibility, and by using this to support the intermediate portion of the fluorescent tube, the fluorescent tube can be prevented from being deformed or damaged, and the liquid crystal display device can also be used. The display luminance is prevented from being lowered and uneven brightness.
JP 2001-210126 A

  However, the light source support device 50 described in the above prior art is effective in preventing the deformation and breakage of the fluorescent tube and the reduction in the display luminance and the luminance unevenness of the liquid crystal display device, but is made of a transparent material. Since the light radiated from the light source passes through the material in the light source support device or the through hole provided in the reflective plate, the side opposite to the light source arrangement side of the reflective plate is provided. This causes a problem of being transmitted through the screen.

  Therefore, in order to solve the above-described problem, the present invention provides a through-hole provided in a mounted plate, with the support portion for supporting the light source and the locking portion of the light source support device formed integrally with the locking portion. A backlight device that is mounted in a hole and supports the light source, wherein at least a part of the light source support device is molded by light transmission preventing means and is emitted from the light source when mounted on the mounted plate. However, it is possible to prevent the light from passing through the through hole to the side opposite to the light source side of the mounted plate.

  By forming in this way, it is possible to prevent the light emitted from the light source from being transmitted to the side of the mounted plate facing the light source.

  At this time, the light source support device is a backlight device according to claim 1, wherein at least a portion fitted in the through-hole is molded by the light transmission preventing means when mounted on the mounted plate.

  Further, the light source support device is formed by a light transmission preventing means at least a portion that closes the through hole on the support portion side from the mounted plate when mounted on the mounted plate. A device.

  And it is set as the backlight apparatus characterized by using the said to-be-mounted board as a reflecting plate.

  And it is set as the liquid crystal display device provided with the said backlight apparatus.

  According to the present invention, it is possible to prevent light emitted from the light source from being transmitted to the side of the mounted plate facing the light source.

  Below, the 1st Embodiment of this invention is described with FIG. FIG. 1A shows a cross-sectional view of a light source support device according to a first embodiment of the present invention, and FIG. 1B shows the light source support device of FIG. Sectional drawing at the time of supporting a light source is shown.

  In each embodiment, a case where a fluorescent tube is used as a light source and a reflecting plate is used as a mounted plate will be described as an example.

  Referring to FIG. 1, a light source support device 1 is provided on a base 4 on a side opposite to a support part 2 for supporting an annular fluorescent tube 5 and a support part 2 arrangement side of the base 4. It has a shape to which the locking portion 3 is attached.

  The support portion 2 is formed of a transparent material, and the cross section thereof is formed in a shape in which a part of an arc is cut out. The fluorescent tube 5 is fitted into the cutout portion, whereby the fluorescent tube 5 is supported by the support portion 2. It can be fixed to.

  Further, the locking portion 3 is made of a colored material, and the base 4 side has a neck portion 3a slightly smaller in diameter than the through-hole 7 provided in the reflecting plate 6 and a head portion 3b having a diameter larger than that of the through-hole 7. Is provided. And when the latching | locking part 3 is attached to the through-hole 7, when the neck part 3a fits in the through-hole 7, and the head 3b contact | abuts the surface on the side facing the light source arrangement | positioning side of the reflecting plate 6, light source The support device 1 is prevented from falling off the reflecting plate 6.

  The base 4 is made of a transparent material like the support 2 and has a role as a base for the support 2.

  When the fluorescent tube 5 is mounted on the reflecting plate 6 by the light source support device 1 and is lit with the above configuration, the light emitted from the fluorescent tube 5 is emitted to the arrangement side of the fluorescent tube 5 rather than the reflecting plate 6. However, light is hardly transmitted to the side of the reflecting plate 6 opposite to the side where the fluorescent tube 5 is disposed, because the locking portion 3 is formed in a colored manner. It can be solved.

  However, as shown in FIG. 1, when the locking portion 3 is not hidden behind the fluorescent tube 5 when viewed from the side opposite to the reflecting plate arrangement side with respect to the fluorescent tube 5, colored Only the portion where the locking portion exists is darkened. Therefore, for example, when uniform light is required as in a backlight device of a liquid crystal display device, if the light source support device 1 is used, a dark part is partially generated and it cannot be said that the light emission state is good. There is a risk of becoming.

  Therefore, this improved example will be described as a second embodiment. The second embodiment is formed as shown in FIG.

  FIG. 2A is a cross-sectional view of a light source support device according to a second embodiment of the present invention, and FIG. 2B is a view in which the light source support device of FIG. Sectional drawing at the time of supporting a light source on the support apparatus is shown.

  In order to avoid duplication of explanation, only the points different from the first embodiment will be described in the second embodiment. In the second embodiment, the locking portion 3 is disposed on the fluorescent tube 5 with a reflector. This is different from the first embodiment in that the locking portion 3 and the support portion 2 are formed so as to be hidden behind the fluorescent tube 5 when viewed from the opposite side. That is, it is assumed that the fluorescent tube 5 supported by the support part 2 and the locking part 3 are arranged at positions facing each other with the base 4 interposed therebetween.

  When formed in this way, the colored locking portion is not conspicuous when viewed from the side opposite to the reflecting plate arrangement side with respect to the fluorescent tube 5 and requires uniform light as in the backlight device of a liquid crystal display device, for example. In this case, it is possible to prevent a dark part from being generated.

  1 and 2 according to the first and second embodiments of the present invention describe the case where a plurality of support portions 2 and locking portions 3 are provided. It is not limited to a single number. This also applies to each embodiment described below. Moreover, when forming in single, as shown in FIG. 3, it is good also as a form which abolishes the base | substrate 4 and attaches the latching | locking part 3 to the support part 2 directly.

  Next, the example which applied 2nd Embodiment to the illuminating device is demonstrated using FIG. FIG. 4A shows a schematic front view of the lighting device of the present invention, and FIG. 4B shows a schematic sectional view of FIG.

  In FIG. 4, the illuminating device 15 has a plurality of fluorescent tubes 5 connected to a driving device (not shown) attached to the reflecting plate 6 by the light source support device shown in the second embodiment. The reflecting plate 6 is arranged to face the plurality of fluorescent tubes 5 and has a shape in which a frame 21 for fixing the lighting device 15 to another member is attached. For example, the reflecting plate 6 is formed on the surface of an aluminum plate. Specific examples include those coated with high reflectivity and those obtained by applying a sheet with high reflectivity to the surface of an aluminum plate.

  When the fluorescent tube 5 is turned on by the driving device configured as described above, the light emitted from the fluorescent tube 5 is formed with the locking portion 3 in a colored manner, so that the fluorescent plate 5 arrangement side of the reflector 6 is formed. Does not transmit light in the opposite direction (the direction of arrow C in FIG. 4B), and furthermore, the side opposite to the locking portion 3 of the fluorescent tube 5 (that is, FIG. 4B). Then, when the fluorescent tube 5 is viewed from the direction of arrow B), the locking portion 3 is hidden by the fluorescent tube 5. Therefore, since the colored portion is behind the fluorescent tube 5, there is no dark spot with low reflectivity, and it is possible to provide a uniform light emitting device with few spots as a lighting device.

  Note that the color separation boundary between the locking portion 3 and the base 4 referred to in the first and second embodiments is not necessarily clear, and further, as shown in FIG. A part of 4 may be colored similarly to the locking portion 3. Even at this time, the colored portion is hidden from the fluorescent tube 5 when the fluorescent tube 5 is viewed from the side facing the engaging portion 3 of the fluorescent tube 5. If the fluorescent tube 5 and the colored portion are arranged to face each other, uniform light emission with few spots can be obtained as described above.

  In the above, an example in which the light source support device is integrally molded with a plurality of colors has been described. However, the configuration having the same effect is not limited to the case of integrally molding.

  Next, embodiments in which a plurality of colors are not integrally molded will be described using third, fourth, and fifth embodiments.

  The third embodiment is configured as shown in FIG. FIG. 6A shows a cross-sectional view of a light source support device according to a third embodiment of the present invention, and FIG. 6B shows the light source support device of FIG. Sectional drawing at the time of supporting a light source is shown.

  In order to avoid duplication of explanation, only the differences from the second embodiment will be described for the third embodiment. The difference is that the locking portion 3 is molded in color in the second embodiment. However, in the third embodiment, the locking portion 3 is formed transparently in the same manner as the support portion 2 and the base body 4, and the surface of the locking portion 3 that is molded transparently is opposed to the arrangement side of the fluorescent tube 5. The point is that a colored film 13 is applied. Specifically, the film 13 can be formed by means such as painting with a colored material, plating, or sticking of colored tapes.

  FIG. 7A shows a cross-sectional view of the light source support device according to the fourth embodiment of the present invention, and FIG. 7B shows the light source support device of FIG. Sectional drawing at the time of supporting a light source on the support apparatus is shown.

  In order to avoid duplication of explanation, only the differences of the fourth embodiment from the second embodiment will be described. The difference is that in the second embodiment, the locking portion 3 is molded in color. However, in the fourth embodiment, the locking portion 3 is formed to be transparent like the support portion 2 and the base 4 and the screw portion having an outer diameter smaller than that of the through hole 7 provided in the reflecting plate 6. 14 is formed, and the locking portion 3 is inserted into the through hole 7 of the reflecting plate 6, and then a colored cover body 16 formed at least in a shape larger than the outer periphery of the through hole 7 is screwed. 2 is attached to the reflecting plate 6.

  As a specific example of the cover body 16, it can be formed of a resin material or a metal material molded in color.

  FIG. 8A shows a cross-sectional view of the light source support device according to the fifth embodiment of the present invention, and FIG. 8B shows the light source support device of FIG. Sectional drawing at the time of supporting a light source on the support apparatus is shown.

  In order to avoid duplication of explanation, only the differences of the fifth embodiment from the second embodiment will be described. The difference is that in the second embodiment, the locking portion 3 is molded in color. However, in the fifth embodiment, the locking portion 3 is abolished, and in the second embodiment, the locked portion 17 is provided at the position where the locking portion 3 of the base body 4 is attached. After the colored locking means 18 is inserted into the through hole 7, the locking means 18 is locked to the locked portion 17.

  Specific examples of the locked portion 17 and the locking means 18 include a case where the locked portion 17 is a screw hole and the locking means 18 is a colored (metal or resin) screw. It is not limited to examples.

As described above, even if formed as in the third, fourth, and fifth embodiments, light is applied to the side of the reflector 6 opposite to the side where the fluorescent tube 5 is disposed, as in the second embodiment. Can be prevented, and when a uniform light is required as in a backlight device of a liquid crystal display device, for example, it can be prevented that a dark part is partially generated. Therefore, even if the third, fourth, and fifth embodiments are applied to the example in which the second embodiment described above is applied to a lighting device, a lighting device with uniform light emission with few spots is provided. Is possible. Further, since a plurality of colors are not integrally formed, it is easy to manufacture.

  In addition, about the 3rd, 4th and 5th embodiment, although the example which added the change to a part of 2nd Embodiment was shown, the same change can also be applied to 1st Embodiment. . Also in this case, similarly to the first embodiment, it is possible to prevent light from being transmitted to the side of the reflector 6 opposite to the side where the fluorescent tube 5 is disposed.

  Further improvements can be added to the first to fifth embodiments described above. That is, for example, in an illuminating device that requires uniform light, such as a backlight device of a liquid crystal display device, the light emitted from the fluorescent tube 5 is uniformed in a planar shape on the side of the fluorescent tube 5 opposite to the reflecting plate 6. A diffusion plate 7 (see FIG. 10) for diffusing light to emit light may be disposed. However, the diffusion plate 7 may be warped by the influence of heat or moisture of the fluorescent tube 5. When the warp width is large, the effect of diffusing light, which is a function of the diffusion plate 7, is diminished, and there is a problem that the planar light emission state is not achieved.

  Therefore, a means for preventing the warp of the diffusion plate 7 is required. By providing the means for preventing the warp integrally in the first to fifth embodiments, the diffusion plate 7 is not increased without increasing the number of parts. Can prevent warping.

  As an embodiment in this case, a modified example of the second embodiment will be described as a sixth embodiment with reference to FIG. FIG. 9A shows a cross-sectional view of a light source support device according to a sixth embodiment of the present invention, and FIG. 9B shows a state in which the light source support device of FIG. Sectional drawing at the time of supporting a light source is shown.

  In order to avoid duplication of explanation, only the improvements added to the second embodiment will be described for the sixth embodiment. As a means for preventing the diffusion plate 7 from warping, the support 4 on the side of the support portion 2 of the base 4 is arranged. From the surface, a substantially conical projection 8 protruding from the side most opposed to the base 4 of the fluorescent tube 5 held by the support portion 2 is formed.

  When this light source support device is used for the illumination device 15, it is formed as shown in FIG. FIG. 10 shows a cross-sectional view of the illumination device 15.

  With regard to FIG. 10, a difference from the example in which the second embodiment shown in FIG. 4 is applied to the illumination device 15 will be described. The difference is that the sixth embodiment is replaced with the second embodiment. The point which applied and the arrangement | positioning side of the reflecting plate 6 which opposes the fluorescent tube 5 are the points which provided the diffusion plate 7 which diffuses light in the opposite side.

  By forming the illumination device 15 as described above, light is not transmitted to the side of the reflecting plate 6 opposite to the fluorescent tube 5 side, and the protrusion 8 is formed even if the diffusion plate 7 warps to the fluorescent tube 5 side. Therefore, it is possible to form an illumination device whose warpage is regulated at low cost.

  Further, an example in which the illumination device 15 is used in the liquid crystal display device 20 is shown in FIG. FIG. 11 shows a liquid crystal panel 10 provided on the side of the diffusing plate 7 opposite to the side where the reflecting plate 6 is arranged, a driving device (not shown) for the liquid crystal panel 10, and a liquid crystal in addition to the illumination device shown in FIG. An optical sheet 9 disposed between the panel 10 and the diffusion plate 7 is held by a frame body 11.

  The optical sheet 9, the liquid crystal panel 10, and the frame 11 are not particularly described because they can be applied by appropriately combining known techniques.

  By forming as described above, there is no problem that light is transmitted to the side of the reflecting plate 6 opposite to the fluorescent tube 5 side, and the display of the liquid crystal panel 10 is caused by the colored locking portion 3. The present invention provides a liquid crystal display device 20 in a good light emitting state that has no luminance unevenness for a long period of time because no luminance unevenness occurs and no luminance unevenness due to warping of the diffusion plate 7 occurs. Can do.

  In the above description, the case where the fluorescent tube 5 is used as the light source has been described. However, even when another light source such as an LED is used, the above light source support device can exhibit the same effect. Needless to say, any of the light source support devices described in the embodiments can be applied to a lighting device and a liquid crystal display device.

  And about the example of the support part 2, although the support part 2 is formed only from the transparent material and the cross section cuts out only a part of circular arc, it demonstrates suitably, according to the shape of a light source. Obviously, it is possible to add Of course, other configurations are not limited to this example, and can be appropriately changed according to the design.

(A) is sectional drawing of the light source support device concerning the 1st Embodiment of this invention.

(B) is sectional drawing at the time of attaching a light source support apparatus of (a) to a reflecting plate, and supporting a light source to this light source support apparatus.
(A) is sectional drawing of the light source support device concerning the 2nd Embodiment of this invention.

(B) is sectional drawing at the time of attaching a light source support apparatus of (a) to a reflecting plate, and supporting a light source to this light source support apparatus.
Sectional drawing at the time of making the support part and the latching | locking part of 2nd Embodiment into one. (A) is a schematic front view of the illuminating device of this invention.

(B) is (a) schematic sectional drawing.
Sectional drawing which shows the deformation | transformation aspect of 2nd Embodiment. (A) is sectional drawing of the light source support device concerning the 3rd Embodiment of this invention.

(B) is sectional drawing at the time of attaching a light source support apparatus of (a) to a reflecting plate, and supporting a light source to this light source support apparatus.
(A) is sectional drawing of the light source support device concerning the 4th Embodiment of this invention.

(B) is sectional drawing at the time of attaching a light source support apparatus of (a) to a reflecting plate, and supporting a light source to this light source support apparatus.
(A) is sectional drawing of the light source support device concerning the 5th Embodiment of this invention.

(B) is sectional drawing at the time of attaching a light source support apparatus of (a) to a reflecting plate, and supporting a light source to this light source support apparatus.
(A) is sectional drawing of the light source support device concerning the 6th Embodiment of this invention.

(B) is sectional drawing at the time of attaching a light source support apparatus of (a) to a reflecting plate, and supporting a light source to this light source support apparatus.
Sectional drawing at the time of using 6th Embodiment for an illuminating device. Sectional drawing at the time of using the 6th Embodiment of this invention for a liquid crystal display device. The attachment figure of the light source support device concerning a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source support apparatus 2 Support part 3 Locking part 4 Base | substrate 5 Light source (fluorescent tube)
6 Mounted plate (reflector)
7 Diffusion plate 8 Projection 9 Optical sheet 10 Liquid crystal panel 15 Illumination device 20 Liquid crystal display device

Claims (5)

A backlight device that supports the light source by mounting the locking portion of the light source support device in which the support portion that supports the light source and the locking portion are integrally molded in a through-hole provided in a mounting plate. There,
Molding at least a part of the light source support device by a light transmission preventing means;
A backlight that prevents light emitted from the light source from being transmitted through the through hole to a side opposite to the light source side of the mounted plate when mounted on the mounted plate. apparatus.   2. The backlight device according to claim 1, wherein the light source support device is formed by light transmission preventing means at least a portion fitted in the through hole when the light source support device is mounted on the mounting plate.   2. The light source support device according to claim 1, wherein when the light source support device is attached to the attachment plate, at least a portion that closes the through hole on the support portion side of the attachment plate is molded by light transmission preventing means. The backlight device described.   4. The backlight device according to claim 1, wherein the mounted plate is a reflecting plate. A liquid crystal display device comprising the backlight device according to claim 1.

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