JPH11111030A - Surface lighting device - Google Patents

Abstract

(57) [Problem] In a case where maintenance such as replacement of a light source can be easily performed without removing a light guide plate, and a gap between the light guide plate and the holding frame is smaller than a predetermined value. Also, the light source cover can be smoothly inserted and removed. SOLUTION: A light guide plate 2 and a light source cover 5 which is detachably held between one side 2a, 3a of a holding frame 3 holding the light guide plate 2 are provided, and the light source 4 is held inside the light source cover 5. The light guide plate 2 and the holding frame 3 are provided on the light source cover 5.
A flexible pressing body 56 is provided in contact with one of the sides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a surface illumination device incorporated in a liquid crystal display device.

[0002]

2. Description of the Related Art As described in Japanese Patent Application Laid-Open No. 8-5841, a surface illuminating device is a light guide plate which illuminates the front side by reflecting light incident from the side by a reflection means on the back side. And a light source using a straight tube lamp disposed on one side of the light guide plate, and the light source is held on the light guide plate using a light source reflector made of an aluminum sheet.
The surface lighting device is housed in a housing having a window with a liquid crystal display panel disposed above the surface of the light guide plate, and the housing is housed in a case of a liquid crystal display device used for a navigator monitor of an automobile. Is done.

There is also known a surface illuminating device including the light guide plate and the light source, and a holding frame surrounding the light guide plate and the light source. The surface lighting device is housed in a case of the liquid crystal display device together with a housing in which the liquid crystal display panel is housed.

[0004]

As described above, the conventional light source is held on the light guide plate by the light source reflection plate.
If the light source needs to be replaced due to a long period of use, the brightness of the light source is reduced, the quality of the light source is originally poor, or the light source is unexpectedly broken, the light source holding the light source is required. It is necessary to remove the light plate and further remove the light source from the light guide plate, and there has been a problem that maintenance such as replacement of the light source is difficult to perform.

[0005] The present invention has been made in view of the above circumstances, and provides a light source cover that can be inserted into and removed from the light guide plate and the holding frame, and holds the light source on the light source cover.
Further, by providing a flexible pressing body on the light source cover, maintenance such as replacement of the light source can be easily performed without removing the light guide plate, and furthermore, due to the bending of the molded synthetic resin holding frame. An object of the present invention is to provide a surface illumination device that can smoothly insert and remove a light source cover even when a gap between a light guide plate and a holding frame becomes smaller than a predetermined value due to a variation in deformation and assembly accuracy. Aim.

[0006]

According to the present invention, there is provided a surface illuminating apparatus comprising: a light guide plate configured to illuminate a front surface with light reflected on a back surface; a holding frame surrounding and holding the light guide plate; In a surface illumination device comprising a light plate and a light source interposed between at least one side of the holding frame, the light guide plate and one side of the holding frame from one of two side surfaces adjacent to one side of the holding frame. A light source cover is inserted and held so that it can be inserted and removed, and the light source is held inside the light source cover,
The light source cover is provided with a flexible pressing body that contacts one side of the light guide plate and one of the holding frames.

In the present invention, since the light source is held by the light source cover which can be inserted and removed from the light guide plate and the holding frame, the light source can be easily replaced by operating the light source cover. Maintenance, such as replacement of the device, can be easily performed. In addition, since the light source cover is provided with a flexible pressing member, the deformation of the holding frame is deformed and the assembly accuracy is varied, and the gap between the light guide plate and the holding frame is smaller than a predetermined value. Even in this case, the light source cover can be smoothly inserted and removed without difficulty.

[0008] Further, the invention is characterized in that an enclosing wall is provided at a joint corner between one side and a side surface of the holding frame so as to removably surround an end of the light source cover. According to the present invention, the light source cover can be satisfactorily held by a simple structure in which only the surrounding wall is provided on the holding frame, and the cost of the holding frame and, consequently, the cost of the entire apparatus can be reduced.

In addition, the light source includes a lead wire, and a light source reflector for reflecting light of the light source is provided in the light source cover, and the lead wire is provided between the light source reflector and the light source cover. It is characterized in that a guide passage for guiding is formed. According to the present invention, since the lead wire can be protected by inserting the lead wire into the guide passage between the light source cover and the light source reflector, special care must be taken when removing and inserting the light source cover together with the light source. It is possible to effectively prevent the lead wire from being damaged without paying a fee.

[0010] Further, the light source cover is provided with an engaging portion capable of engaging with at least one of a front surface and a rear surface of the light guide plate. According to the present invention, since the light source cover can be inserted and removed by engaging with the surface of the light guide plate, the light source cover can be removed without abutting a printed wiring circuit capable of controlling the operation of the liquid crystal display panel. Can be inserted and removed smoothly.

[0011] Further, one of the light source cover and the holding frame is provided with an engagement recess, and the other is provided with an engagement projection which can be engaged with the engagement recess. According to the present invention, the position of the light source cover with respect to the holding frame can be determined by the engagement of the engagement protrusion with the engagement recess, so that the light source cover can be prevented from being accidentally moved. .

Further, the light source cover is provided with a finger hook protruding outward from the holding frame. According to this invention, the light source cover can be inserted and removed by pinching the finger hook projecting outward from the holding frame, so that the light source cover can be easily inserted and removed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings showing the embodiments. FIG. 1 is an exploded perspective view showing a configuration of a surface illumination device according to the present invention, with a part omitted, FIG. 2 is an enlarged exploded perspective view, and FIG. 4 is a perspective view of a state in which the light source and the light source reflector are held by the light source cover.

This surface illumination device is used as a backlight device of a liquid crystal display device. The light guide plate 2 illuminates the front surface by reflecting light incident from the side by the reflection means 1 on the rear surface, and the light guide plate. Holding frame 3 that surrounds and holds light plate 2
And a light source 4 using a straight tube lamp interposed between one side and the other side of the light guide plate 2 and the holding frame 3.

The light source 4 includes the light guide plate 2 and the holding frame 3.
Is held inside a light source cover 5 which is detachably held between one side 2a, 3a and between the other side 2b, 3b, and further, the light of the light source 4 is directed toward the light guide plate 2 in the light source cover 5. A light source reflector 6 for reflecting light is provided.

The light guide plate 2 is made of a transparent acrylic plate having a property of reducing light loss among synthetic resin materials, and is formed in a square shape as a whole, and the one side 2a, 3a and the other side 2a are formed.
A pair of connecting pieces 21... having insertion holes project from side surfaces 2c and 2d adjacent to b and 3b, respectively. As shown in FIG. 7, a large number of dots 22 for irregularly reflecting incident light are integrally formed on the back surface of the light guide plate 2, and the pattern of the dots 22 has a white color to prevent reflected light from leaking. A reflector 23 is laminated, and the reflector 23 and the dot 2
2 constitutes the reflection means 1.

The pattern of the dots 22 is, as known,
The dot area increases as the distance from the light-incident side end increases, and the dot density increases.The degree of blur decreases as the distance from the light-incident side end increases, so that the variation in the brightness of each part decreases. ing.

On the surface of the light guide plate 2, a diffusion plate 7 is laminated so as to hide the dots 22 on the back surface from appearing on the surface and to spread the reflected light on the surface. The diffusion plate 7 is made of a frosted glass-like polycarbonate sheet or the like with fine scratches such as a satin pattern on the surface. A light collecting plate 8 is laminated on the diffusion plate 7 as necessary, so that light is prevented from escaping to the outside and light is collected within the directivity range of the liquid crystal. This light collector 8
Is constituted by a polycarbonate sheet or a lens sheet made of polyester. Light guide plate 2
On one side 2a and the other side 2b, there is provided an engagement step 24 which is recessed from the surface and engages with the light source cover 5.

The holding frame 3 is molded using a synthetic resin material. As shown in FIGS. 1 and 10, a square bottom 3c facing the back surface of the light guide plate 2 and the bottom 3c are formed.
Are formed with one end 3a and the other side 3b rising from one side and the other side, and sides 3d and 3e adjacent to the one side 3a and the other side 3b.

The rising walls 3f, 3g facing the side surfaces 2c, 2d of the light guide plate 2 are provided inside the side portions 3d, 3e.
And four pedestals 3h for receiving the connecting pieces 21.
Are provided, and each connecting piece 2 of the light guide plate 2 is tightened by a tightening screw 9 tightening a screw hole formed in the pedestal 3h.
When the light source cover 5 is fixed to the pedestal 3h, as shown in FIG. 10, the light source cover 5 is located between the one side 3a and the other side 3b and the one side 2a and the other side 2b of the light guide plate 2. The insertion passages 10, 10 through which the cable can be inserted and removed are formed.

Further, at each corner of the holding frame 3, FIG.
As shown in FIG. 0, enclosure walls 31 and 31 surrounding one end in the length direction of the light source cover 5 and an enclosure wall 3 surrounding the other end.
2 and 32 are provided, and the insertion passages 10 are extended so as to penetrate the surrounding walls 31 and 32. Further, as shown in FIG. 1, the surrounding walls 31, 31 are provided with engaging concave portions 33, 33 which can be engaged with the engaging projections provided on the light source cover 5.

As shown in FIG. 2, the light source 4 includes a straight tube lamp 41 using a long hot cathode fluorescent discharge tube, and two light sources 4 connected to both ends of the straight tube lamp 41 via crimp terminals. One set of lead wires 42, 43 and these lead wires 42, 43
And a rubber lamp holder 44, 44 fitted on the joint with the straight tube lamp 41.

These lamp holders 44, 44 are formed in a substantially rectangular column, and a fitting hole 44a for fitting the straight tube lamp 41 is provided at one end, and the fitting hole 44a is formed at the other end. Two communicating holes 44b and two lead wire drawing holes 44c are provided. Further, the outer surface of one end of each of the lamp holders 44, 44 has its twill portion cut off in an inclined manner, and when the light source reflector 6 is fitted and held,
As shown in FIGS. 6 and 7, a guide passage 11 for guiding the lead wire 43 is formed between the light source reflector 6 and the light source cover 5, and the outer end of the other end has a right angle. A guide passage 44d is provided, which is cut off in a shape and guides the lead wire 43.

The light source cover 5 has a pair of side walls 51 and 52 facing each other with a dimension substantially the same as the thickness of the light guide plate 2,
The light source 4 is received in a concave receiving portion 5a formed in a substantially U-shaped cross section by a connecting wall 53 connecting the side walls 51 and 52. The one side wall 51 is provided with the lamp holders 44 and 4 of the light source 4.
The holding pieces 54, 54 for pressing and holding the light source 4 on the connecting wall 53 are protruded so as to be bent, and the light source cover 5 of the light source 4 is engaged with the end faces of the lamp holders 44, Locking pieces 55, 55 for preventing movement with respect to are protrudingly provided.

Further, at both ends in the length direction of the connecting wall 53 of the light source cover 5, flexible pressing members 56, 56 which protrude outward and come into contact with one side 3a of the holding frame 3 are provided. At one longitudinal end of each of the side walls 51, 52, an engagement projection 57, 57 engageable with the engagement recess 33, 33 is provided. Each of the pressing members 56, 56 and each of the engagement protrusions 5
7, 57 are formed by bending a part left in the substantially U-shaped hole so as to be able to bend outward.

At one end of each of the side walls 51, 52, finger hooks 58, 58 projecting outward from the surrounding walls 31, 31 of the holding frame 3 are formed by bending.
58, the light source cover 5 can be inserted into and removed from the insertion passages 10. Further, one side wall 51 is formed wider than the other side wall 52, and when the pressing bodies 56, 56 are in contact with the bottom wall 53 of the holding frame 3 at its width direction end, as shown in FIG. 7. And an engaging portion 59 which engages with the engaging step portion 24 of the light guide plate 2.

As shown in FIG. 2, the light source reflector 6 is fitted and held on the outer surfaces of the ends of the lamp holders 44 of the light source 4, and includes a bottom wall 61 and both sides of the bottom wall 61. Inclined side wall 6 rising outward from the side
2 and 62, and opposing side walls 63, 63 standing up at substantially the same intervals from the inclined side walls 62, 62. When the light source reflector 6 is placed in the light source cover 5, the inclined side walls 62, 62 are provided. Guide passages 11, 1 for guiding the lead wire 43 between the light source cover 5 and
1 is generated.

As shown in FIG. 3, the light source reflector 6 is fitted to the outer surface of one end of the lamp holders 44, 44, and then the lamp holder 4 is fixed by the adhesive tape 12.
4, 44 fixed.

The light source cover 5 and the light source reflector 6
Is a metal plate, but may be a synthetic resin.

In the surface illumination device configured as described above, the light guide plate 2 is put in the holding frame 3, and the connecting pieces 21 of the light guide plate 2 are tightened by the tightening screws 9,. Fixed to. The surface illumination device in which the light guide plate 2 is incorporated in the holding frame 3 is connected to an input terminal of a personal computer or the like in a recess between the side 3d of the holding frame 3 and the rising wall 3f. A power supply substrate 20 having a printed wiring circuit capable of controlling the operation of the panel and an inverter device for supplying power to the light source 4 is arranged, and the lead wires 42 and 43 are connected to the inverter device of the power supply substrate 20 by the connector 14. In addition, the liquid crystal display panel is disposed above the surface of the light guide plate 2, and the liquid crystal display panel and the surface illumination device are mounted in a case of a liquid crystal display device used for a navigator monitor of an automobile. Is configured.

The straight tube lamp 41, the lead wires 42, 4
3. The light source 4 including the lamp holders 44, 44 is inserted into the light source reflector 6 except for both ends in the length direction,
The light source reflector 6 and the lamp holders 44 are connected by the adhesive tape 13 to form a light source unit.

Further, this light source unit is inserted into the light source cover 5, and the holding pieces 54, 54 and the locking pieces 55, 5
The light source unit is fixed to the light source cover 5 by bending the light source unit 5. In this case, one end lead wire 42 drawn from one lamp holder 44 is connected to the connector 14 as shown in FIG. 3, and the other lead wire 43 drawn from the other lamp holder 44 is connected to the light source unit. Lead passage 4 between the outer surface of the light source and the inner surface of the light source cover 5
It can be guided by 4d, 11 and pulled out to the same side as the one-side lead wire 42.

That is, the guide passages 44 of the lead wires 43 are formed on the outer surfaces of the ends of the lamp holders 44,
d is provided, and a guide passage 11 for the lead wire 43 is formed between the inner surface of the light source cover 5 and the outer surface of the light source reflector 6 by utilizing the twill angle of the light source reflector 6, so that the other lamp holder is provided. The lead wire 43 on the other side drawn out from 44 is drawn out through each of the guide passages 44d and 11 and connected to the connector 14 together with the lead wire 42 on the one side. Therefore, the lead wire 43 on the other side is connected to the light source cover 5 and the light source reflector 6.
The lead wire 43 can be protected by being inserted into the guide passage 11 between the lead wire 43 and the light source unit. Sticking can be effectively prevented. In addition, since the lead wires 42 and 43 connected to both ends of the lamp 41 can be connected to one connector 14, one side 33 of the holding frame 3 can be connected.
It can be connected to the inverter device of one power supply board 20 provided in the recessed portion between d and the rising wall 3f.

Then, the end of the light source cover 5 opposite to the finger hooking piece 58 is inserted into the insertion passage 1 from the inside of the one surrounding wall 31 of the holding frame 3.
Insert at 0. In this case, the engaging portion 59 of the light source cover 5 is engaged with the engaging step portion 24 of the light guide plate 2. Accordingly, since the light source cover 5 is guided by the engagement step portion 24 as a guide surface, it can be smoothly inserted between the one side 2a, 3a and the other side 2b, 3b.

Since the bottom wall 53 of the light source cover 5 is provided with outwardly protruding flexible pressing members 56, 56, the deformation / light guide plate 2 due to the bending of the one side 3a is not moved. Even when the dimension between the one sides 2a and 3a or the distance between the other sides 2b and 3b is smaller than a predetermined value due to the variation in assembling accuracy when assembling by fixing with the tightening screw 9, The pressing members 56, 56 contact the one side 3a and the other side 3b and bend. Therefore,
The light source cover 5 can be smoothly inserted without being affected by the deformation and the like.
The light source cover 5 is moved to the light guide plate 2 by the bending of the pressing members 56, 56.
Can be brought closer to one side 2a and the other side 2b, so that the gap between the light source cover 5 and the light guide plate 2 can be made small. Accordingly, it is possible to reduce the leakage of light emitted from the light source 4 to the outside, the uniformity, and the variation in luminance, and accordingly, the light amount of the light source can be effectively used.

When the light source 4 needs to be replaced because the brightness of the light source 4 is reduced due to long-time use, the quality of the light source 4 is originally poor, or the light source 4 is unexpectedly broken. Then, the finger is hooked on the finger hooking piece 58 of the light source cover 5 and pulled, so that the engagement recess 3 of the engagement projection 57 is formed.
3 can be easily disengaged and the pressing body 5
The light source cover 5 can be easily and smoothly inserted and removed against the contact resistance between the one side 3a and the other side 3b.

In the embodiment described above, the pressing body 56 of the light source cover 5 is configured to be in contact with one side 3a and the other side 3b of the holding frame 3, but in addition, the pressing body 56 may be connected to the light guide plate 2. It may be configured to contact one side 2a and the other side 2b.

In the embodiment described above, the engaging portion 24 that engages with the back surface of the light guide plate 2 is provided on the side wall 51 of the light source cover 5.
An engagement portion that engages with the back surface of the light guide plate 2 may be provided.

In the embodiment described above, the light source 4 is arranged on one side 2a and the other side 2b of the light guide plate 2. However, this light source is provided on the one side 2a and the other side 2b. It is good also as a structure arrange | positioned at only one.

[0040]

According to the surface illumination device of the present invention, the light source is held by the light source cover which can be inserted into and removed from the light guide plate and the holding frame. And maintenance such as replacement of the light source can be easily performed. Also,
Since the light source cover is provided with a flexible pressing member, the deformation between the light guide plate and the holding frame becomes smaller than a predetermined value due to the deformation and assembly accuracy variation due to the bending of the holding frame. In this case, the light source cover can be easily and smoothly inserted and removed.

Further, the light source cover can be satisfactorily held by a simple structure in which an enclosing wall which surrounds the end of the light source cover so as to be able to be inserted and removed is provided at the joint corner between one side and the side surface of the holding frame. Thus, the cost of the holding frame, and thus the cost of the entire apparatus, can be reduced.

Further, a light source reflector is provided in the light source cover, and a guide path for guiding a lead wire is formed between the light source reflector and the light source cover.
By inserting a lead wire into the guide passage, the lead wire can be protected. Therefore, it is possible to effectively prevent the lead wire from being damaged without paying special attention when inserting and removing the light source cover together with the light source.

Further, since the light source cover is provided with an engaging portion which can be engaged with at least one of the front surface and the back surface of the light guide plate, the light source cover is engaged with the surface of the light guide plate and is inserted and removed. Can be. Therefore, the light source cover can be smoothly inserted and removed without making contact with a printed wiring circuit or the like that enables the operation of the liquid crystal display panel to be controlled.

Further, since the engaging recess is provided on one of the light source cover and the holding frame and the engaging protrusion is provided on the other, the holding of the light source cover is achieved by engaging the engaging protrusion with the engaging recess. The position with respect to the frame can be determined, and it is possible to prevent the light source cover from being moved carelessly.

Also, since the light source cover is provided with the finger hooks projecting outward from the holding frame, the finger hooks projecting outward from the holding frame can be picked up and pulled out of the light source cover. The light source cover can be easily inserted and removed.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view in which a part of a surface illumination device according to the present invention is omitted.

FIG. 2 is an enlarged exploded perspective view in which a part of the surface illumination device according to the present invention is omitted.

FIG. 3 is an enlarged perspective view of a surface illumination device according to the present invention, in which a light source reflector is coupled to a light source, and which is omitted in the middle.

FIG. 4 is a perspective view of a state where a light source and a light source reflector are held in a light source cover of the surface illumination device according to the present invention, with a part thereof omitted.

FIG. 5 is a partially omitted perspective view showing a state where a light source cover is attached to a holding frame of the surface illumination device according to the present invention.

FIG. 6 is a sectional view taken along line XX of FIG. 10 of the surface illumination device according to the present invention.

FIG. 7 is a sectional view taken along line YY of FIG. 10 of the surface illumination device according to the present invention.

FIG. 8 is a sectional view of only one end of a light source in the surface illumination device according to the present invention.

FIG. 9 is a left side view of FIG.

FIG. 10 is a plan view of a surface lighting device according to the present invention.

[Explanation of symbols]

 Reference Signs List 2 light guide plate 2a one side 3a one side 3 holding frame 33 engaging recess 4 light source 43 lead wire 5 light source cover 56 pressing body 57 engaging projection 58 finger hook 6 light source reflector 11 guide passage

Claims (6)

[Claims] 1. A light guide plate configured to illuminate a front surface with light reflected on a back surface, a holding frame surrounding and holding the light guide plate, and interposed between at least one side of the light guide plate and the holding frame. A surface lighting device comprising: a light source; and a light source cover that is inserted and held between one side of the light guide plate and one side of the holding frame detachably from one of two side surfaces adjacent to one side of the holding frame. A surface lighting device, wherein the light source is held inside the light source cover, and the light source cover is provided with a flexible pressing body that contacts one side of the light guide plate and one of the holding frames. . 2. The surface lighting device according to claim 1, further comprising an enclosing wall surrounding an end of the light source cover so as to be able to be inserted and removed at a joint corner between one side and a side surface of the holding frame. 3. The light source includes a lead wire, and further includes, in the light source cover, a light source reflector for reflecting light of the light source, and the lead wire is disposed between the light source reflector and the light source cover. 3. The surface lighting device according to claim 1, wherein a guide passage for guiding is formed. 4. The surface lighting device according to claim 1, wherein the light source cover includes an engaging portion that can be engaged with at least one of a front surface and a rear surface of the light guide plate. 5. One of the light source cover and the holding frame includes:
The surface lighting device according to any one of claims 1 to 4, further comprising an engagement recess, and the other including an engagement protrusion capable of engaging with the engagement recess. 6. The light source cover according to claim 1, further comprising a finger hook protruding outward from the holding frame.
The surface lighting device according to any one of the above.