JP2005050821A - Plane light source device and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the luminance unevenness of outgoing light caused by the transformation of a light control sheet. <P>SOLUTION: Light from a light source unit attached to a frame is emitted in a planar shape through a light guide plate and a light control sheet in the frame. Among these, the light source unit is equipped with a fluorescent lamp 12, a reflector storing the fluorescent lamp 12, and a reflector supporter attached to the frame in a state of supporting the reflector. The fluorescent lamp 12 is insertion-coupled with at least a pair of O-rings 35, and also, a plurality of O-rings 54 are insertion-coupled so as to be adjacent with each other between the O-rings 35, and 35. Then, the fluorescent lamp 12 is supported in the reflector through the O-rings 35 and 54. When the reflector is warped, the O-ring 54 is pressed to the incidence surface of the light guide plate, whereby the warp of the reflector is corrected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface light source device that illuminates an image display unit such as a liquid crystal display panel used in a portable personal computer, a navigation device, a portable information communication terminal, an electronic dictionary, various monitors, and the like, and the surface light source device. The present invention relates to an image display device including

  2. Description of the Related Art Conventionally known liquid crystal display devices as image display devices are used in portable personal computers, etc., and illuminate a liquid crystal display panel (image display unit) with planar illumination light emitted from a surface light source device. An image is displayed on the surface of the display panel (see Patent Document 1).

  16 and 18 show a surface light source device 101 used in such a liquid crystal display device 100. FIG. As shown in these drawings, in the surface light source device 101, the reflection sheet 3, the light guide plate 4, and the plurality of light control sheets 5 to 8 are sequentially accommodated in the resin frame 2, and the light guide plate 4 is incident. The light source unit 11 is arranged on the surface 10 (side surface) side. The light source unit 11 includes a fluorescent lamp 12 as a rod-shaped light source disposed so as to face the side surface of the light guide plate 4, a reflector 13 that reflects light from the fluorescent lamp 12 and guides the light to the incident surface 10 of the light guide plate 4, And a metallic reflector support 14 that is fixed to the frame 2 in a state where the reflector 13 that accommodates the fluorescent lamp 12 is supported.

  Then, the surface light source device 101 configured as described above emits light from the fluorescent lamp 12 in a planar shape from the emission surface 36 of the light guide plate 4, and outputs light from the light guide plate 4 to a plurality of light control sheets. By passing 5-8, the emitted light from the light guide plate 4 is condensed in the direction toward the liquid crystal display panel 16 to form uniform and bright planar illumination light. Thus, the liquid crystal display panel 16 is illuminated.

  In recent years, the liquid crystal display device 100 used particularly for portable personal computers is required to be more portable and portable, and to be easier to see. The display area (display screen) has been enlarged. As a result, in such a liquid crystal display device 100, the liquid crystal display panel 16 is narrowed and the peripheral portion of the liquid crystal display panel 16 is reduced.

  As a result, in the surface light source device 101 used in the liquid crystal display device 100 as described above, the thickness of the resin frame 2 is reduced in order to cope with the narrowing of the frame of the liquid crystal display panel 16, and in particular, the resin frame Among the two, the portion (first side 21) in which the fluorescent lamp 12 is accommodated has low rigidity. Therefore, the plate-like base portion 43 of the reflector support 14 is fixed to the lower surfaces of a pair of sides (second side 30 and third side 31) substantially orthogonal to the first side 21 of the frame 2 with screws (not shown), The side wall portions 44 to 46 erected from the plate-like base portion 43 of the reflector support 14 are engaged with the outside of the first to third sides 21, 30, 31, and the frame 2 is reinforced by the reflector support 14. It has become.

JP2000-231102A

  However, in the resin frame 2 of such a surface light source device 101, since the thickness of the first side 21 is extremely thin compared to the thickness of the other side, the shrinkage after injection molding is the first side. The other side is larger than 21, and the first side 21 may be slightly bent and deformed inward as shown by the two-dot chain line in FIG. 16 or FIG. FIG. 16 exaggerates the amount of deformation in order to emphasize the deformation of the frame 2.

  In such a case, if the amount of bending deformation of the first side 21 of the frame 2 is larger than the gap amount between the frame 2 and the light control sheets 5 to 8, the light control sheets 5 to 8 are compressed by the frame 2. In addition, wrinkles may occur in the light control sheets 5 to 8, and luminance unevenness of the emitted light due to the wrinkles of the light control sheets 5 to 8 may occur.

  In addition, the reflector 13 is formed into a long shape with a substantially U-shaped cross section as shown in FIGS. 17 and 18 by processing a metal thin sheet metal, and also functions as a reinforcing member of the frame 2. Compared to the support 14, the rigidity is small. In addition, such a reflector 13 is engaged with rubber lamp holders 22 and 23 fitted to the fluorescent lamp 12 at both ends thereof, and both ends thereof are attached to the frame 2 together with the lamp holders 22 and 23. Although it is configured to be held, the intermediate portion excluding both ends thereof is not locked to the frame 2 or the reflector support 14.

  Accordingly, when the reflector 13 is warped during sheet metal processing as indicated by a two-dot chain line shown in FIG. 17, the intermediate portion of the reflector 13 faces the light guide plate 4 side as shown in FIGS. 20 to 21. The gap between the fluorescent lamp 12 and the side surface (incident surface 10) of the light guide plate 4 is narrowed more than necessary, and the fluorescent lamp 12 is inserted into the light guide plate 4 also from the exit surface 36 side of the light guide plate 4. Light L is incident, and outgoing light with high luminance is partially generated by the amount of light incident from the outgoing surface 36 side. Further, the light control sheets 5 to 8 are compressed by the reflector 13, and wrinkles are generated in the light control sheets 5 to 8, and brightness unevenness of the emitted light due to the wrinkles of the light control sheets 5 to 8 occurs. is there.

  Therefore, the present invention provides a surface light source device that can effectively prevent uneven brightness of emitted light due to deformation of a frame or a reflector and enables uniform and bright illumination, and an image display device including the surface light source device. The purpose is to do.

  In the surface light source device according to the first aspect of the present invention, light from the light source unit attached to the frame is emitted in a planar shape via a light guide plate and a light control sheet accommodated in the frame. Yes. The light source unit includes a rod-shaped light source disposed so as to face the side surface of the light guide plate, a reflector that houses the rod-shaped light source, and guides the light of the rod-shaped light source to the side surface of the light guide plate, and the reflector And a reflector support that is attached to the frame in a state where it is supported. The rod-shaped light source is fitted with at least a pair of annular members, and a plurality of annular members are fitted between the annular members. Moreover, the said rod-shaped light source is supported in the said reflector via the said annular member. Here, the annular member includes an O-ring and a substantially C-shaped ring. Further, the annular member may be formed such that the outer shape is formed in a shape that is substantially in close contact with the inner surface of the reflector and the side surface of the light guide plate, and the inner surface is fitted into a rod-shaped light source. That is, the annular member may be any member that is disposed so as to surround the outer periphery of the rod-shaped light source and can support the rod-shaped light source in the reflector.

  According to the present invention having such a configuration, even if the reflector is warped and the rod-shaped light source is curved and deformed so as to approach the side surface (incident surface) of the light guide plate by the reflector, the pair of annular members The warp of the reflector can be corrected by the elastic force of the plurality of annular members arranged in the, and a sufficient space can be secured between the fluorescent lamp and the light guide plate, so that the light guide plate does not approach the bar light source excessively can do. As a result, the light control sheet is not compressed by the reflector and does not generate wrinkles.

  In the surface light source device according to the invention of claim 2, light from the light source unit attached to the frame is emitted in a planar shape via a light guide plate and a light control sheet accommodated in the frame. Yes. The light source unit includes a rod-shaped light source disposed so as to face the side surface of the light guide plate, a reflector that houses the rod-shaped light source, and guides the light of the rod-shaped light source to the side surface of the light guide plate, and the reflector And a reflector support that is attached to the frame in a state where it is supported. The rod-shaped light source is fitted with at least a pair of annular members, and a substantially cylindrical elastic member is fitted between the annular members. The rod-shaped light source is supported in the reflector via the annular member and a substantially cylindrical elastic member.

  According to the present invention having such a configuration, the substantially cylindrical elastic member corresponds to the plurality of adjacent annular members in the present invention, and the warp of the reflector can be corrected. As a result, the light control sheet is not compressed by the reflector and does not generate wrinkles.

  According to a third aspect of the present invention, there is provided an image display device comprising any one of the above surface light source devices and an image display panel illuminated with light emitted from the surface light source device. .

  According to the image display device having such a configuration, the image display panel is illuminated by the uniform and bright planar illumination light emitted from the surface light source device, and the display quality of the image can be improved.

  As described above, the surface light source device according to the present invention corrects the curved deformation of the frame and the warp of the reflector, thereby preventing the light control sheet from being pressed by the frame and the reflector and generating wrinkles. Since it is possible to prevent the light from the fluorescent lamp from entering from the light exit surface side of the light plate, uneven brightness of the surface light emitted from the light guide plate is suppressed, and uniform and bright surface illumination is possible.

  The image display device according to the present invention is configured such that the image display panel is illuminated with uniform and bright planar illumination light emitted from the surface light source device as described above. Quality is improved.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
[First Embodiment]
1 to 3 show a surface light source device 1 according to a first embodiment of the present invention. Among these, FIG. 1 is a plan view of the surface light source device 1. FIG. 2 is an exploded plan view showing the surface light source device 1. 3 is an enlarged cross-sectional view of the surface light source device 1 cut along the line AA in FIG.

(Schematic configuration of surface light source device)
As shown in these drawings, the surface light source device 1 includes a frame 2 that houses component parts, a reflection sheet 3 that is sequentially stacked in the frame 2, a light guide plate 4, and a plurality of light control sheets 5. ˜8 and a light source unit 11 attached to the frame 2 so as to face the incident surface (one side surface) 10 of the light guide plate 4. The light source unit 11 includes a fluorescent lamp 12 as a rod-shaped light source, a reflector 13 that accommodates the fluorescent lamp 12, and a reflector support 14 that supports the reflector 13 that accommodates the fluorescent lamp 12. Among these, the reflector 13 reflects the light of the fluorescent lamp 12 and guides it to the incident surface 10 of the light guide plate 4.

(flame)
Among these, as shown in FIGS. 1-8, the flame | frame 2 is formed in the substantially rectangular shape by injection-molding white synthetic resins, such as PC (polycarbonate) and PMMA (polymethyl methacrylate), A light guide plate accommodating portion 15 for accommodating and supporting the reflection sheet 3, the light guide plate 4 and the plurality of light control sheets 5 to 8, and an image display panel 16 such as a liquid crystal display panel with respect to the surface of the uppermost light control sheet 8. An image display panel housing portion 17 that houses and supports the light source unit 11 with a slight gap and a light source housing portion 18 that houses the fluorescent lamp 12 and the reflector 13 of the light source unit 11 are formed. In order to reduce the size and weight of the surface light source device 1, the frame 2 is formed as thin as possible, and the bottom surface 20 of the light guide plate housing portion 15 is thinned. The bottom surface 20 of the light guide plate accommodating portion 15 has a shape that can support the reflection sheet 3, the light guide plate 4, and the like and can be attached with a control component (not shown) of the image display panel 16.

  Further, as shown in detail in FIGS. 4 to 7, the frame 2 has both ends of a fluorescent lamp 12 to be described later at both ends of the lower surface side of one side (first side) 21 on the incident surface 10 side of the light guide plate 4. Lamp holder housing recesses 24 and 25 are formed, respectively, to which the lamp holders 22 and 23 of the part are engaged. The reflector 13 is accommodated on the lower surface side of the first side 21 of the frame 2. Therefore, the first side 21 of the frame 2 is formed thinner than the other side and has a lower rigidity than the other side. Therefore, the first side 21 is reinforced by the reflector support 14. That is, as shown in detail in FIGS. 3 and 8, the upper surface of the first side 21 has a substantially rectangular hook receiving recess 27 with which the plurality of hooks 26 of the reflector support 14 are engaged, and the reflector support. Protrusions 28 that are engaged with the plurality of hooks 26 of the body 14 are formed. The hook 26 of the reflector support 14 is accommodated in the hook accommodating recess 27 of the first side 21, and the hook 26 of the reflector support 14 is engaged with the projection 28 of the first side 21. The 1st edge | side 21 and the reflector support body 14 can be integrated so that attachment or detachment is possible, and the curve deformation | transformation inside the 1st edge | side 21 of the flame | frame 2 (two-dot chain line of FIG. 16) can be prevented. . In addition, it is preferable to determine the shape of the hook 26 and the amount of depression of the hook receiving recess 27 so that the upper surface of the hook 26 does not protrude upward from the upper surface of the first side 21. In this way, other parts or the like are not easily caught on the hook 26, and the hook 26 is difficult to be detached from the protrusion 28.

  The frame 2 has substantially rectangular cutouts formed on both ends of the light guide plate 4 and the reflection sheet 3 inside the second side 30 and the third side 31 that are substantially orthogonal to the first side 21. Positioning protrusions 34 that engage with the portions 32 and 33 are formed. Thereby, even if vibration or impact is applied to the surface light source device 1, it is possible to restrict the light guide plate 4 from moving in the frame 2, and the light guide plate 4 collides with the fluorescent lamp 12. It becomes possible to prevent damage.

(Light source unit)
The light source unit 11, as shown in FIGS. 1 to 3 and 9 to 12, supports a fluorescent lamp 12 as a rod-shaped light source, a reflector 13 that accommodates the fluorescent lamp 12 (see FIG. 9), and the reflector 13. The reflector support body 14 is provided (see FIG. 10). Among these, the fluorescent lamp 12 is engaged with rubber lamp supports 22 and 23 at both ends thereof, and a pair of rubber O-rings 35 are spaced apart from each other at substantially symmetrical positions with respect to the central portion thereof. They are opened and fitted (see FIG. 2). The reflector support 14 is engaged with the end portion of the reflector 13 and is also engaged with lamp support housing recesses 24 and 25 formed on the first side 21 of the frame 2 (see FIG. 5, see FIG. The O-rings 35 and 35 elastically support the fluorescent lamp 12 in the reflector 13 in order to prevent the fluorescent lamp 12 from directly contacting the inner surface of the reflector 13 and to protect the fluorescent lamp 12 from impact. It is supposed to be. A ground side cable 39 is accommodated in a space between the first side 21 and the reflector 13 (see FIG. 3).

  The reflector 13 is obtained by sheet metal processing of a thin metal plate such as a stainless steel plate, and is in close contact with the first plate-like portion 37 that is in close contact with the end of the emission surface 36 of the light guide plate 4 and the lower surface side of the reflective sheet 3. And a second plate-like portion 38 supported by the reflector support 14, and a rising wall portion 40 connecting the first plate-like portion 37 and the second plate-like portion 38. It is the elongate body formed in the length substantially the same as the 1st edge | side 21 of this. Among these, the first plate-like portion 37 prevents light from entering the light guide plate 4 from the incident surface 10 side (side surface side) end of the exit surface 36 of the light guide plate 4. In addition, a protrusion 41 that protrudes to the lower surface side is formed at a substantially central portion in the longitudinal direction (the direction along the axis of the fluorescent lamp 12) of the tip of the second plate-shaped portion 38. A hole 42 that engages with the protrusion 41 of the reflector 13 is formed in the plate-like base portion 43 of the reflector support 14. Accordingly, by engaging the protrusion 41 of the reflector 13 with the hole 42 of the reflector support 14, even if the reflector 13 is warped due to sheet metal processing (see the two-dot chain line in FIG. 17), the warp is corrected. In addition, even if an action that causes deformation of the reflector 13 occurs, the reflector 13 can be positioned with respect to the reflector support 14 without being deformed.

  The reflector support 14 includes a plate-like base 43 fixed to the lower surface side of the second side 30 and the third side 31 of the frame 2 with screws (not shown), an outer surface of the first side 21 of the frame 2, and a second side. Side walls 44 to 46 erected from the plate-like base 43 so as to support the outer surface of the side 30 and the outer surface of the third side 31, respectively. The reflector support 14 is a metal plate such as a stainless steel plate formed by sheet metal processing, similar to the reflector 13 described above, but is thicker and more rigid than the reflector 13 described above, and reinforces the frame 2. It is supposed to be. In addition, the reflector support 14 has a pair of hooks 26 which are engaged with the protrusions 28 formed on the first side 21 at the upper end of the side wall portion 44 located on the outer surface side of the first side 21 of the frame 2. Is formed. Then, by engaging the hook 26 of the reflector support 14 with the protrusion 28 of the frame 2, it is possible to prevent the first side 21 of the frame 2 from being bent and deformed inward. The hook 26 is formed with a hole 26b that engages with the protrusion 28 of the first side 21 inside a substantially rectangular frame portion 26a.

  In such a light source unit 11, first, as shown in FIGS. 3 and 9, the fluorescent lamp 12 is accommodated in the reflector 13, and then, as shown in FIG. 10, the reflector 13 is combined with the reflector support 14. . At this time, as described above, the protrusion 41 of the reflector 13 is engaged with the hole 42 of the reflector support 14. That is, the second plate-like portion 38 of the reflector 13 and the plate-like base portion 43 of the reflector support 14 are engaged with each other in an uneven manner. Thereby, while being able to position the reflector 13 and the reflector support body 14, the curved deformation of the reflector 13 can be corrected. Next, as shown in FIG. 11, the hook 26 of the reflector support 14 is engaged with the projection 28 on the first side 21 of the frame 2, and the second plate-like portion 38 of the reflector 13 and the plate of the reflector support 14 are engaged. Screws (not shown) are inserted into the screw holes 47 and 48 of the base 43, and the reflector 13 and the reflector support 14 are fixed to the lower surfaces of the second side 30 and the third side 31 of the frame 2 with the screws. Thereby, the frame 2 and the light source unit 11 are integrated. Thereafter, the reflection sheet 3, the light guide plate 4, and the plurality of light control sheets 5 to 8 are accommodated in the light guide plate accommodating portion 15 of the frame 2, and the surface light source device 1 is assembled (see FIGS. 1 to 3). Further, the liquid crystal display panel 16 is accommodated in the image display panel accommodating portion 17 of the frame 2, and the liquid crystal display device 50 as an image display device is assembled (see FIG. 3).

(Light guide plate)
The light guide plate 4 is formed of PC, PMMA, cycloolefin resin material, or the like having excellent light transmittance, and has a wedge shape in which the longitudinal cross-sectional shape in the direction orthogonal to the fluorescent lamp 12 becomes thinner as the distance from the fluorescent lamp 12 increases. The shape of the emission surface (upper surface) 36 is a substantially rectangular shape. The light guide plate 4 is formed with substantially rectangular cutouts 32 at both end portions on the incident surface 10 side. The cutouts 32 are formed on the second side 30 and the third side of the frame 2. It is adapted to be engaged with a positioning protrusion 34 formed on the inner side of 31. The light guide plate 4 has its outer dimensions determined in consideration of a difference in temperature expansion between the light guide plate 4 and the frame 2, a difference in hygroscopic expansion, a manufacturing error, and the like, and the conditions under which the surface light source device 1 is used. Below, a slight gap is formed between the other side surface except the incident surface 10 and the side wall of the light guide plate housing 15. The light guide plate 4 has sufficient rigidity so as not to be easily deformed, unlike a flexible sheet-like member such as a reflection sheet 3 and light control sheets 5 to 8 described later. In such a light guide plate 4, the light from the fluorescent lamp 12 incident on the inside from the incident surface 10 propagates inside the light guide plate 4, and enters the emission surface 36 at an angle less than the critical angle in the process of propagation. Light is emitted from the emission surface 36. Various means for emitting light from the light exit surface 36 of the light guide plate 4 are conventionally known, and can be appropriately selected and adopted from these.

(Reflective sheet)
The reflection sheet 3 is formed in a sheet shape with a resin material excellent in light reflectivity (for example, white PET (polyethylene terephthalate)), and is a surface (lower surface) opposite to the light exit surface 36 of the light guide plate 4. It has a rectangular shape corresponding to 51 and functions to reflect the light emitted from the lower surface 51 of the light guide plate 4 and return it to the inside of the light guide plate 4. In the reflection sheet 3, notches 33 corresponding to the notches 32 of the light guide plate 4 are formed at both ends of the front end of the fluorescent lamp 12, and the notches 33 are the second parts of the frame 2. It is adapted to be engaged with positioning protrusions 34 formed inside the second side 30 and the third side 31.

(Light control sheet)
A diffusion sheet (first light control sheet) 5 disposed so as to face the emission surface 36 of the light guide plate 4 and a pair of prism sheets (second sheet) disposed so as to face the upper surface side of the diffusion sheet 5. And a third light control sheet) 6 and 7 and a protective sheet (fourth light control sheet) 8 having a light diffusibility disposed on the upper surface side of the pair of prism sheets 6 and 7 is a light control sheet. Is configured. These first to fourth light control sheets 5 to 8 are formed of a resin material excellent in light transmittance (for example, PET (polyethylene terephthalate)), and correspond to the emission surface 36 of the light guide plate 4. It is formed in a substantially rectangular shape. The first to fourth light control sheets 5 to 8 are sequentially accommodated in the light guide plate accommodating portion 15 above the light guide plate 4 and are also engaged with the frame 2 by fixing means such as a tape or a clip (not shown). It is stopped and the displacement movement in the frame 2 is prevented.

(Operations and effects of the first embodiment)
In the surface light source device 1 according to the present embodiment configured as described above, the protrusions 28 formed on the first side 21 of the frame 2 are engaged with the hooks 26 of the reflector support 14, and the first side 21. Is corrected so that the light control sheets 5 to 8 are not pressed by the first side 21 to be wrinkled, and the light emitted from the wrinkles of the light control sheets 5 to 8 is corrected. Brightness unevenness is not generated.

  In addition, the surface light source device 1 according to the present embodiment engages the protrusion 41 formed on the second plate-like portion 38 of the reflector 13 with the hole 42 formed on the plate-like base portion 43 of the reflector support 14, thereby reflecting the reflector. The reflector 13 can be positioned with respect to the support 14, and even if the reflector 13 is curved and deformed inward as shown in FIG. 17 (even if warpage due to sheet metal processing occurs), the reflector 13 Since the deformation can be corrected, the distance between the fluorescent lamp 12 and the incident surface 10 of the light guide plate 4 can be maintained in an appropriate state, and the incident surface 10 side end of the exit surface 36 of the light guide plate 4 is the first plate of the reflector 13. Therefore, the light from the fluorescent lamp 12 can be effectively prevented from entering the light guide plate 4 from the light exit surface 36 of the light guide plate 4. In addition, as described above, the deformation of the reflector 13 can be corrected and the distance between the fluorescent lamp 12 and the incident surface 10 of the light guide plate 4 can be maintained in an appropriate state, so that the light control sheets 5 to 8 are pressed by the reflector 13. No wrinkles. Therefore, according to the present embodiment, it is possible to prevent occurrence of uneven brightness of the emitted light due to the incident light from the exit surface 36 of the light guide plate 4.

  Further, in the surface light source device 1 according to the present embodiment, the projection 41 of the reflector 13 and the hole 42 of the reflector support 14 that engages with the projection 41 are covered with the reflection sheet 3. The hole 42 of the support 14 is not visually recognized from the light exiting surface 36 side of the light guide plate 4 and does not cause a problem such as light leakage.

  Further, in the liquid crystal display device 1 according to the present embodiment, the liquid crystal display panel 16 is illuminated with the planar uniform illumination light by the surface light source device 1 as described above. Is possible.

  In addition, although this Embodiment illustrated the aspect which forms the protrusion 41 of the reflector 13, and the hole 42 of the reflector support body 14 in one place, it is not restricted to this, The hole of the protrusion 41 of the reflector 13 and the reflector support body 14 A plurality of 42 may be formed.

  Moreover, in this Embodiment, although the protrusion 41 is formed in the front-end | tip of the 2nd plate-shaped part 38 of the reflector 13, it is not restricted to this, The part (2nd 2nd) located in the lower surface side of the reflective sheet 3 What is necessary is just to form in a part of plate-shaped part 38).

  Further, in the present embodiment, the protrusion 41 is formed so as to cut the tip of the second plate-like portion 38 of the reflector 13 to the lower surface side (the plate-like base portion 43 side of the reflector support 14). You may form so that the 2nd plate-shaped part 38 may bulge partially to the lower surface side. In this case, the plate-like base portion 43 of the reflector support 14 is formed with a recess or hole that engages with the bulging protrusions. In addition, a protrusion may be formed on the plate-like base portion 43 of the reflector support 14, and a hole or a recess that engages with the protrusion may be formed on the second plate-like portion 38 of the reflector 13. In this case, it is desirable to prevent the protrusion from projecting to the upper surface side of the second plate-shaped portion 38.

  Further, in the present embodiment, a protrusion is formed on the lower surface side of the hook 26 of the reflector support 14, and a recess that engages with the protrusion is formed on the first side 21 of the frame 2. You may make it correct | amend the curved deformation of the 1st edge | side 21 of the flame | frame 2 by engaging the recess of 1 edge | side 21 with uneven | corrugated.

  Moreover, in this Embodiment, although the aspect which forms the hook 26 in two places in the reflector support body 14 was illustrated, as long as the curved deformation of the 1st edge | side 21 of the flame | frame 2 can be corrected, it engages with this. Only one protrusion 28 may be provided, and three or more hooks 26 and protrusions 28 engaged therewith may be formed.

Further, in the present embodiment, ribs 52 and 53 extending substantially along the axial direction of the fluorescent lamp 12 at a portion located on the tip side of the plate-like base portion 43 of the reflector support 14 and on the lower surface side of the reflection sheet 3. As a result, the rigidity of the reflector support 14 is increased.
[Second Embodiment]
This embodiment exemplifies a mode different from the above-described first embodiment as means for correcting the warp of the reflector 13. That is, as shown in FIG. 13, the surface light source device 1 according to the present embodiment includes a plurality of light sources at a substantially central portion between a pair of O-rings (annular members) 35 and 35 fitted to the fluorescent lamp 12. An O-ring (annular member) 54 is arranged in close contact.

  With this configuration, when the reflector 13 is warped so as to be bent inward (see FIG. 17), the rod-like fluorescent lamp 12 is also bent and deformed by the reflector 13, and the fluorescent lamp 12 is almost at the center. It is also conceivable that the deformation amount of the portion becomes the largest, and the plurality of O-rings 54 arranged at the substantially central portion of the fluorescent lamp 12 are pressed against the incident surface 10 of the light guide plate 4. However, according to the present embodiment, since the pressing force received from the incident surface 10 of the light guide plate 4 can be dispersed by the plurality of O-rings 54, one O-ring 35 similar to the pair of O-rings 35 and 35 is provided. Compared with the case where only one piece is arranged at the center of the fluorescent lamp 12, the elastic deformation amount of each O-ring 54 is reduced, and a sufficient space can be secured between the light guide plate 4 and the fluorescent lamp 12. In other words, the warp of the reflector 13 is corrected by the plurality of O-rings 54 disposed in the substantially central portion of the fluorescent lamp 12, and a sufficient space can be secured between the fluorescent lamp 12 and the light guide plate 4. It should be noted that the width dimension W of the plurality of O-rings 54 disposed almost at the center of the fluorescent lamp 12 is preferably W = 2d to 4d when the wire diameter of the pair of O-rings 35 and 35 is d. . If W <2d, the effect of correcting the reflector 13 cannot be obtained sufficiently, and if W> 4d, the light blocking portion becomes too large, and this light blocking portion may be visually recognized as a variation in the luminance of the emitted light. is there.

  According to the present embodiment having such a configuration, the deformation of the reflector 13 can be corrected by the plurality of O-rings 54 arranged in the substantially central portion of the fluorescent lamp 12, and therefore the incident surface 10 of the fluorescent lamp 12 and the light guide plate 4. A sufficient space can be secured, and the end surface of the light exit surface 36 of the light guide plate 4 on the incident surface 10 side can be reliably shielded by the first plate portion 37 of the reflector 13. It is possible to effectively prevent the light incident surface 36 from entering the light guide plate 4. In addition, as described above, the deformation of the reflector 13 is corrected, and a sufficient space between the fluorescent lamp 12 and the incident surface 10 of the light guide plate 4 can be secured, so that the light control sheets 5 to 8 are pressed by the reflector 13. No wrinkles. Therefore, according to the present embodiment, as in the first embodiment described above, it is possible to prevent the occurrence of uneven brightness in the emitted light due to the incident light from the exit surface 36 of the light guide plate 4.

  The second embodiment described above exemplifies a mode in which the plurality of O-rings 54 are arranged in the substantially central portion of the fluorescent lamp 12 in close contact with each other. However, the present invention is not limited to this, and FIGS. As shown to a), you may make it fit the substantially cylindrical rubber ring (elastic member) 55 to the substantially intermediate part of a pair of O-rings 35 and 35. FIG. Here, as shown in FIG. 15B, the ring 55 may be formed with a slit 56 extending over the entire length in the width direction to facilitate the fitting operation to the fluorescent lamp 12. Even with such a configuration, the same effects as those of the second embodiment described above can be obtained. The width dimension W of the ring 55 is preferably W = 2d to 4d, where d is the diameter of the O-ring 35, as in the second embodiment.

  Further, in the second embodiment described above, an example in which a plurality of O-rings 54 are arranged in the substantially central portion of the fluorescent lamp 12 in close contact with each other is illustrated, but each O-ring 54 is slightly separated. It may be arranged.

(Other embodiments)
The surface light source device 1 according to each of the above embodiments diffuses the light emitted from the emission surface 36 of the light guide plate 4 with the first light control sheet 5 to achieve a uniform luminance distribution, and then In addition, the third light control sheets 6 and 7 are focused in the normal direction of the exit surface 36 of the light guide plate 4 to increase the proportion of light that can be effectively used for illumination, so that bright and uniform surface illumination is performed. It has become. In the surface light source devices 1 of these embodiments, for example, the second light control sheet 6 has a substantially triangular prism surface extending in a direction substantially parallel to the fluorescent lamp 12 in a direction perpendicular to the fluorescent lamp 12. The third light control sheet 7 is formed with a large number of prism surfaces having a substantially triangular cross section extending in a direction substantially perpendicular to the prism surface of the second light control sheet 6. The fourth light control sheet 8 is mainly used as a protective sheet for preventing the prism surface from being scratched as described above. However, a function as a diffusion sheet is necessary to achieve more uniform illumination light. Given accordingly.

  Further, the present invention is not limited to the aspect of the surface light source device 1 according to each of these embodiments. For example, the prism surface similar to the prism surface of the second light control sheet 6 is formed on the lower surface 51 of the light guide plate 4. And the second light control sheet 6 may be omitted. In addition, the present invention only needs to have a configuration in which at least one light control sheet is disposed on the light exit surface 36 side of the light guide plate 4. That is, as the specific configurations of the light guide plate 4 and the light control sheets 5 to 8, various configurations conventionally known in this type of surface light source device 1 can be employed.

  Moreover, although each said embodiment illustrated that the longitudinal cross-sectional shape orthogonal to the entrance plane 10 of the light-guide plate 4 was a substantially wedge shape, it is not restricted to this, For example, it orthogonally crosses the entrance plane 10 of the light-guide plate 4 You may make it use the thing of a substantially rectangular shape, or another cross-sectional shape.

  In the above embodiment, the light source unit 11 is disposed only on the incident surface 10 side of the light guide plate 4, but is not limited thereto, and may be disposed on a plurality of side surfaces of the light guide plate 4. .

1 is a plan view of a surface light source device according to a first embodiment of the present invention. It is a top view which decomposes | disassembles and shows the surface light source device which concerns on 1st Embodiment. It is an expanded sectional view of the surface light source device shown cut along the AA line of FIG. It is a top view of a frame. It is the figure (side view) seen from the B direction of FIG. FIG. 6 is a diagram (a diagram illustrating a lower surface on the first side of the frame) viewed from a direction C in FIG. 5. FIG. 6 is an enlarged cross-sectional view taken along line DD in FIG. 5. It is a figure which shows the engagement state of the hook of a reflector support body, and the protrusion of a flame | frame. It is a top view of the reflector which accommodated the fluorescent lamp. It is a top view of a light source unit. It is a top view of the flame | frame with which the light source unit was attached. It is a perspective view which shows a reflector and a reflector support body partially. It is a figure which shows the fluorescent lamp which concerns on the 2nd Embodiment of this invention. It is a figure which shows the fluorescent lamp which concerns on the modification of 2nd Embodiment. (A) is a perspective view which shows the 1st example of a ring, (b) is a perspective view which shows the 2nd example of a ring. It is a top view which shows the conventional surface light source device. It is a top view which shows the conventional fluorescent lamp and a reflector. It is an expanded sectional view cut | disconnected and shown along the EE line | wire of FIG. It is sectional drawing of the surface light source device which shows the curved deformation state of a flame | frame. It is sectional drawing which shows the malfunction occurrence state of the conventional surface light source device resulting from the curvature of a reflector. It is sectional drawing which expands and shows a part of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Surface light source device, 2 ... Frame, 4 ... Light guide plate, 5-8 ... Light control sheet, 10 ... Incident surface (side surface), 11 ... Light source unit, 12 ... Fluorescent lamp (rod-shaped light source) ), 13 ... reflector, 14 ... reflector support, 16 ... liquid crystal display panel (image display panel), 26 ... hook, 35 ... O-ring (annular member), 36 ... exit surface, 50 ... Liquid crystal display device (image display device), 54 ... O-ring (annular member), 55 ... Ring (annular member)

Claims (3)

In a surface light source device in which light from a light source unit attached to a frame is emitted in a planar shape via a light guide plate and a light control sheet accommodated in the frame,
The light source unit is
A rod-shaped light source disposed to face the side surface of the light guide plate;
A reflector that houses the rod-shaped light source and guides the light of the rod-shaped light source to the side surface of the light guide plate;
A reflector support attached to the frame in a state of supporting the reflector,
The rod-shaped light source is fitted with at least a pair of annular members and a plurality of annular members adjacent to each other between the annular members,
The surface light source device, wherein the rod-shaped light source is supported in the reflector via the annular member. In a surface light source device in which light from a light source unit attached to a frame is emitted in a planar shape via a light guide plate and a light control sheet accommodated in the frame,
The light source unit is
A rod-shaped light source disposed to face the side surface of the light guide plate;
A reflector that houses the rod-shaped light source and guides the light of the rod-shaped light source to the side surface of the light guide plate;
A reflector support attached to the frame in a state of supporting the reflector,
The rod-shaped light source is fitted with at least a pair of annular members, and a substantially cylindrical elastic member is fitted between the annular members.
The surface light source device, wherein the rod-like light source is supported in the reflector via the annular member and a substantially cylindrical elastic member.   An image display device comprising: the surface light source device according to claim 1 or 2; and an image display panel illuminated with light emitted from the surface light source device.

Images