JP2003234010A - Flat lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat lighting system wherein the optical loss can be suppressed and the rework is easy. <P>SOLUTION: Notches 36 are formed at a termination side 32 of a housing frame 15 in a flat lighting system 1B, and clips 40 are arranged so as to clamp a guide plate body 2 overstriding the termination side part 32. Protruded parts 45 are formed in the clip 40, and they can press the plate light guide body 2 through the notches 36. Even if the light guide body 2 is shorter in some degree due to dispersion or the like in manufacture, a distance between the light guide body 2 and a rod-like light guide body is kept to be a required length or a shorter length. Since the clip 40 is arranged so as to clamp the plate light guide body 2, the plate light guide body 2 can be surely held. When the clip 40 is removed, holding of the plate light guide body 2 is relieved. Herewith, disassembly in trouble-shooting or rework can be executed quickly and easily, and so this lighting system is very convenient. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar lighting device used for lighting means such as signboards and various display devices, and more particularly to a lighting means for liquid crystal display devices.

[0002]

2. Description of the Related Art Liquid crystal display devices that operate with low power consumption are
Because of its thinness and lightness, there is an increasing demand for display devices mainly for personal computers and mobile phones. Liquid crystal, which is a component of this liquid crystal display device, does not emit light by itself unlike a light emitting element such as a cathode ray tube, and therefore it is necessary to separately use an illumination means for enabling use in a dark place. In particular, in recent years, in the demand for thinner electronic products and power saving, a side light type (light guide plate type) planar lighting device is often used as a lighting unit for illuminating a liquid crystal display device. .

FIG. 12 shows the basic components of the surface illumination device 1. The planar lighting device 1 includes a quadrilateral plate-shaped light guide 2 made of a translucent material, and one end surface 3 of the plate-shaped light guide 2.
Bar-shaped light guide 4 made of a translucent material and arranged to face
And a point light source 6 arranged close to or in contact with the one end surface 5a of the rod-shaped light guide 4. In the planar lighting device 1, the lower surface 7 of the plate-shaped light guide 2 is arranged on the display surface of a reflective liquid crystal display element (not shown).

A light reflection pattern 9 is formed on the upper surface 8 of the plate-shaped light guide 2. The light reflection pattern 9 is composed of a large number of groove portions 10 each having a substantially triangular cross section and a flat portion 11 adjacent to the groove portions 10. The light reflection pattern 9 has a uniform brightness at any position of the plate-shaped light guide 2 regardless of the distance from the rod-shaped light guide 4.
The intervals at which the grooves 10 are formed differ depending on the location. That is, the ratio of the width (occupied area) of the groove 10 to the width (occupied area) of the flat portion 11 is set to gradually increase as the distance from the one end face 3 of the plate-shaped light guide 2 increases. Since the groove portion 10 of the light reflection pattern 9 formed on the plate-shaped light guide 2 is extremely fine, it cannot be visually confirmed when observing the screen.

A light emitting diode is used as the point light source 6. The rod-shaped light guide 4 made of a translucent material is arranged at a predetermined distance along the one end surface 3 of the plate-shaped light guide 2. Optical path changing means 12 is formed on the side surface of the rod-shaped light guide 4 opposite to the side surface facing the plate-shaped light guide 2. In the illustrated example, the optical path changing means 12 is formed by arranging irregularities having a substantially triangular cross section in the longitudinal direction of the rod-shaped light guide 4 according to a certain rule.

In addition, in order to guide the light rays into the plate-shaped light guide 2 with high efficiency, the periphery of the rod-shaped light guide 4 other than the surface facing the plate-shaped light guide 2 is guided by a light reflecting member (reflector). ) 13. The light-reflecting member 13 is a sheet-shaped member such as a film obtained by vapor-depositing a metal such as silver, a white film or a film coated with white paint, or a metal plate such as a mirror-finished aluminum plate that is bent. I am using what I did.

When such a planar lighting device 1 is added to a reflection type liquid crystal display element (not shown), light from the rod-shaped light guide 4 is guided from one end face 3 of the plate-shaped light guide 2 to the plate-shaped light guide 2. While entering the inside of the light body 2 and advancing toward the other end face 14 while repeating reflection and refraction inside the light body 2, the plate-like light guide body 2 is gradually emitted from the lower surface 7 to form a plate shape. The reflective liquid crystal display element arranged adjacent to the light guide 2 is illuminated. Furthermore, since the light reflection pattern 9 is formed on the plate-shaped light guide 2, the amount of light emitted from the lower surface 7 can be made to have a substantially uniform distribution.

Further, the applicant of the present application has filed a patent application for a planar illumination device having a housing frame in which the plate-shaped light guide 2, the rod-shaped light guide 4, the point light source 6 and the like are integrally housed and placed.
1-2348887. By integrating the parts into the housing frame, it is possible to improve the handleability when assembling or disassembling the planar lighting device, or when incorporating it as a display device for mobile phones or the like. . This planar illumination device 1A is shown in FIGS. 13 and 14.

A planar illumination device 1A shown in FIGS. 13 and 14.
The housing frame 15 has a opening 16 for accommodating the plate-shaped light guide 2, a frame-shaped seat 17 formed in the opening 16 for mounting the plate-shaped light guide 2, and a rod-shaped light guide. 4 and one end surface 5a and an end surface (other end surface) 5b opposite to the one end surface 5a
[Refer to FIG. 12] Two concave portions 18 for mounting the point light sources 6 arranged close to or in contact with each other and a flat seat portion 19 for mounting the rod-shaped light guide 4 are provided. The planar lighting device 1A has a reinforcing frame 20 made of metal such as stainless steel and having a U-shaped cross section. The reinforcing frame 20 includes the concave portion 18 and the flat seat portion 19.
Is covered from the upper surface and the lower surface.

A reflective liquid crystal display element (not shown) adjacent to the lower surface 7 of the plate-shaped light guide 2 can be seen through the plate-shaped light guide 2 from the opening 16 of the housing frame 15. ing. In this planar lighting device 1A, the plate-shaped light guide 2, the point light source 6, the rod-shaped light guide 4, and the like are fitted side by side in the housing frame 15, and the one side end surface 3 of the plate-shaped light guide 2 is opposite. The side end surface (other end surface) 14 side is attached to the housing frame 15 with double-sided tape (not shown), and finally the reinforcing frame 20 is attached to prevent the members stored in the housing frame 15 from falling off. ing.

[0011]

By the way, the positional relationship among the plate-shaped light guide 2, the point light source 6 and the rod-shaped light guide 4 is important for obtaining desired optical characteristics. Figure 1
3 and the surface illumination device 1A shown in FIG.
With respect to (see FIG. 12), since it is arranged in the concave portion 18 of the housing frame 15 and its position is held, the relative position of the plate-shaped light guide 2 and the rod-shaped light guide 4 is larger than that of the point light source 6. Become more important. Then, if the length L of the plate-shaped light guide 2 is shorter than the length determined by the design as shown in FIG. Also, the distance M between the rod-shaped light guides 4 becomes longer than a length (hereinafter referred to as a set length) M0 [not shown] determined by design, which causes an optical loss.

With respect to such optical loss, FIG.
Also, in the planar lighting device 1A shown in FIG. 14, it is conceivable to use the reinforcing frame 20 to adjust the distance M between the plate-shaped light guide 2 and the rod-shaped light guide 4 to the set length M0. However, although the reinforcing frame 20 is effective in preventing each member from falling off, each member cannot be pressed and the distance M between the plate-shaped light guide 2 and the rod-shaped light guide 4 cannot be adjusted. Even if the rod-shaped light guide 4 can be pressed against the plate-shaped light guide 2 side, the rod-shaped light guide 4 and the point light source 6 are relatively displaced by that amount. The above problem cannot be solved appropriately. In addition, FIG.
In the prior art shown in FIGS. 3 and 14, since the plate-shaped light guide 2 is held by the double-sided tape, the double-sided tape is stripped off at the time of repair or rework (rework), the adhesive is removed from the adhered member, etc. It is inconvenient to disassemble.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a planar illumination device which can suppress the occurrence of optical loss and can be easily reworked.

[0014]

According to a first aspect of the present invention, there is provided a plate-shaped light guide body made of a translucent material and having a substantially quadrangular shape, and the plate-shaped light guide body is disposed so as to face a side end surface of the plate-shaped light guide body. Rod-shaped light guide made of a translucent material, a point light source arranged close to or in contact with an end face of the rod-shaped light guide, the plate-shaped light guide, the rod-shaped light guide and the point light source In a planar lighting device provided with a housing frame for accommodating and mounting therein, a notch or a hole formed in one side portion of the housing frame on a side separated from the rod-shaped light guide, and the one side portion straddling the cutout or hole. A holding member having a substantially U-shaped cross section, which is provided so as to sandwich the plate-shaped light guide, and a convex portion formed in the holding member and capable of pressing the plate-shaped light guide through the notch or hole. Characterize.

According to a second aspect of the present invention, a substantially quadrangular plate-shaped light guide made of a light-transmissive material and a light-transmissive material arranged to face a side end surface of the plate-shaped light guide. A rod-shaped light guide, a point light source arranged close to or in contact with an end face of the rod-shaped light guide, and the plate-shaped light guide, the rod-shaped light guide and the point light source housed and placed In the planar lighting device including a housing frame, the housing frame is flexible, and the plate shape is provided on the inner wall surface of one side of the housing frame on the side separated from the rod-shaped light guide. It is characterized in that a protrusion is formed so as to protrude toward the light guide and can press the plate-shaped light guide. According to a third aspect of the invention, in the configuration according to the second aspect, one or a plurality of the protrusions are formed in the longitudinal direction of the one side portion. According to a fourth aspect of the present invention, in the configuration according to the second aspect, the protrusion is formed so as to reach or substantially reach both end portions of the one side portion.

According to a fifth aspect of the present invention, a substantially quadrangular plate-shaped light guide made of a light-transmissive material and a light-transmissive material arranged to face a side end surface of the plate-shaped light guide. A rod-shaped light guide, a point light source arranged close to or in contact with an end face of the rod-shaped light guide, and the plate-shaped light guide, the rod-shaped light guide and the point light source housed and placed In the planar lighting device including a housing frame, the housing frame has flexibility, and an inner wall surface of one side of the housing frame on a side separated from the rod-shaped light guide is an upper portion. Accordingly, a wedge-shaped portion that is in contact with the upper edge of the plate-shaped light guide is formed in a shape protruding toward the plate-shaped light guide. According to a sixth aspect of the present invention, in the structure according to the fifth aspect, one or a plurality of the wedge-shaped portions are formed in the longitudinal direction of the one side portion. According to a seventh aspect of the invention, in the configuration according to the fifth aspect,
The wedge-shaped portion is formed so as to reach or substantially reach both end portions of the one side portion. The invention according to claim 8 is characterized in that, in the structure according to any one of claims 2 to 7, one or more notches are formed in the one side portion of the housing frame.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A planar illumination device according to a first embodiment of the present invention will be described below with reference to FIGS. 1 to 4 and with reference to FIGS. 12 and 15. It should be noted that the same or corresponding portions as those of the conventional technique are denoted by the same reference numerals, and the description thereof will be appropriately omitted. 1 to 3, the planar lighting device 1B includes a quadrilateral plate-shaped light guide 2 made of a translucent material.
And a rod-shaped light guide 4 made of a translucent material, and a rod-shaped light guide 4
The two point light sources 6 are separately arranged in close proximity to or in contact with one end surface 5a and the other end surface 5b (see FIG. 12). In this planar lighting device 1B, the lower surface 7 of the plate-shaped light guide 2 is arranged so as to face the display surface of a reflective liquid crystal display element (not shown).

A light reflection pattern 9 is formed on the upper surface 8 of the plate-shaped light guide 2. A light emitting diode is used as the point light source 6. The rod-shaped light guide 4 made of a translucent material is arranged to face the one end surface 3 of the plate-shaped light guide 2. In addition, the light-reflecting member 13 (see FIG. 12) is provided on the periphery of the rod-shaped light guide 4 in the longitudinal direction other than the surface facing the plate-shaped light guide 2 in order to guide light rays into the plate-shaped light guide 2 with high efficiency. ) Is covered by.

The planar lighting device 1B is provided with a housing frame 15 for accommodating and mounting the plate-shaped light guide 2, the rod-shaped light guide 4 and the point light source 6. The housing frame 15 is
As shown in FIGS. 2 to 4, a side portion (hereinafter referred to as a light source side portion) 31 adjacent to the rod-shaped light guide 4 and a light source side portion 31.
And a light source side portion 3 (a side portion separated from the rod-shaped light guide 4; hereinafter referred to as a terminal side portion) 32 facing each other.
1 and two side parts that connect both ends of the end side part 32 (hereinafter, the left side part in FIG. 2 is referred to as a first side part 33 for connection, and the right side part in FIG. 2 is a second side part for connection). And a rectangular opening 16 is formed inside.

The light source side portion 31 is formed with a flat seat portion 19 on which the rod-shaped light guide 4 is placed, and two concave portions 18 provided so as to sandwich the flat seat portion 19. There is. The terminal side portion 32, the connecting first side portion 33, and the connecting second side portion 3
A frame-shaped seat portion 17 is formed on the housing 4 so as to project inside the housing frame 15. On the lower side of the terminal side portion 32 (the back side of the paper of FIG. 2, the lower side of FIG. 4), the terminal side portion 32 is provided.
Is formed in such a manner that it extends in the longitudinal direction and is reduced by the thickness dimension of the clip 40 described later. A lower plate 44 of a clip 40 described later is joined to the step portion 35.

A point light source 6 is placed in each of the two recesses 18. Each point-shaped light source 6 is separately arranged in proximity to or in contact with the one end surface 5a and the other end surface 5b of the rod-shaped light guide 4 placed on the flat seat portion 19. The plate-shaped light guide 2 is placed on the frame-shaped seat portion 17. And
Through the plate-shaped light guide 2 placed in this manner, the opening 1
6, it is possible to see the reflective liquid crystal display element (not shown) adjacent to the lower surface 7 of the plate-shaped light guide 2.

The end side portion 32 of the housing frame 15
Two notches 36 are formed on the upper end side of the. Further, a clip 40 (holding member) is provided so as to sandwich the plate-shaped light guide 2 across the terminal side portion 32. The clip 40 is made of metal such as stainless steel. Resin may be used instead of metal.

As shown in FIGS. 1 and 4, the clip 40 has a width dimension of the housing frame 15 (the end side portion 32).
A plate-like clip body 41 having a length equal to
The clip body 41 is bent and extended from both side portions 42,
Two plates having a substantially U-shaped cross section together with the clip body 41 (the upper plate in FIG. 4 is the upper plate 43, and the lower plate in FIG. 4 is the lower plate 4).
4 ) And have. Upper plate 43 and lower plate 4
4 has the same length as the clip body 41.

The lower plate 44 is formed orthogonal to the clip body 41 and is joined to the step portion 35 of the terminal side portion 32 of the housing frame 15. The upper side plate 43 is bent at an angle slightly smaller than a right angle with respect to the clip body 41, and is capable of exerting a spring force. The tip of the upper side plate 43 contacts the plate-shaped light guide 2 and presses the plate-shaped light guide 2 downward when the clip 40 is assembled.

Two convex portions 45 are formed on the clip body 41. The two convex portions 45 are formed by the two notches 36.
, And the tip portion thereof is projected from the terminal side portion 32. In addition, this planar lighting device 1B
Has a reinforcing frame 20, and by mounting the reinforcing frame 20, each member housed in the housing frame 15 is prevented from falling off.

The planar lighting device 1B is assembled as follows. First, in the housing frame 15,
The plate-shaped light guide 2, the point light source 6, the rod-shaped light guide 4, and the like are fitted side by side, and with the convex portion 45 of the clip body 41 aligned with the notch 36, the tip side of the upper plate 43 is slightly widened. The clip 40 is pressed against the plate-shaped light guide 2 side. By this pressing, the convex portion 45 projects into the housing frame 15 through the cutout 36 and the terminal side portion 32, and pushes the plate-shaped light guide 2 toward the rod-shaped light guide 4.

By pushing the plate-shaped light guide 2 to the rod-shaped light guide 4 side, the plate-shaped light guide 2 is displaced to the rod-shaped light guide 4 side. For this reason, tentatively, due to manufacturing variations and the like, the plate-shaped light guide 2
Even if is slightly shorter, the distance M (see FIG. 15) between the plate-shaped light guide 2 and the rod-shaped light guide 4 can be maintained at a desired value or less. After this, the reinforcement frame 2
0 is attached to prevent the members stored in the housing frame 15 from falling off. Further, since the upper plate 43 exerts a downward force in the state where the clip 40 is assembled as described above, the plate-shaped light guide 2 is sandwiched by the lower plate 44 and the plate-shaped light guide 2 is securely held. Can be held.

Although the plate-shaped light guide 2 is held at a desired position by the clip 40 as described above, the holding of the plate-shaped light guide 2 and the like can be easily released by removing the clip 40. Therefore, even when repairing or reworking (reworking) the surface illumination device 1B, the disassembling work can be performed quickly and easily, which is convenient.

In the present embodiment, since the lower plate 44 is adapted to be joined to the step portion 35 of the terminal side portion 32 of the housing frame 15, it is possible to suppress the downward projection amount of the lower plate 44. The device can be made compact. That is, for example, when the step portion 35 is not formed in the housing frame 15, the lower plate 44 projects downward (downward in FIG. 4) by the thickness of the lower plate 44, so that a large amount of space is required. On the other hand, in the present embodiment, since the lower plate 44 is joined to the step portion 35 as described above, the above space is unnecessary, and the device can be made compact.

In the above embodiment, the case where the length of the upper plate 43 is set to be equal to the length dimension of the clip body 41 and the width dimension of the housing frame 15 is taken as an example, but instead of this, it is shown in FIG. The clip 40A configured as described above may be used. The upper side plate 43A of the clip 40A includes a base portion (hereinafter, referred to as an upper side plate base portion) 43B having the same length as the length dimension of the clip body 41, and both end portions of the upper side plate base portion 43B (the first side portion 33 for connection). And a portion corresponding to the connecting second side portion 34) except the upper plate base portion 43B.
And a tip portion (hereinafter, referred to as an upper plate tip portion) 43C that is connected to the plate-shaped light guide 2 and has a length equal to the width dimension of the plate-shaped light guide 2. The upper plate distal end portion 43C can contact the plate-shaped light guide 2 without contacting the connecting first side portion 33 and the connecting second side portion 34.

By using this clip 40A,
The upper surface 8 of the plate-shaped light guide 2 housed in the housing frame 15 is the upper surface of the first connecting side 33 or the second connecting side.
Even if the level is lower than the upper surface of the side portion 34,
The tip portion 46 of the upper plate tip portion 43C is the first side portion 3 for connection.
The plate-shaped light guide 2 is brought into contact with the plate-shaped light-guide 2 without being constrained by the connection member 3 and the connecting second side portion 34, so that the plate-shaped light-guide 2 can be reliably held.

In the first embodiment, the case where the notch 36 is formed in the terminal side portion 32 has been taken as an example, but instead of this, a hole (not shown) may be formed.

Next, a planar lighting device according to a second embodiment of the present invention will be described based on FIGS. 6 and 7 and with reference to FIGS. 1, 12 and 15. 6 and 7, the housing frame 15C of the planar lighting device 1C is made of a flexible material. The plate-shaped conductor is provided on the upper side (upper side in FIG. 7) of the wall surface 50 inside the end side portion of the housing frame 15C [one side portion separated from the rod-shaped light guide 4 (see FIGS. 1 and 12)] 32C. One protrusion 51 having a shape protruding toward the optical body 2 side is formed so that the plate-shaped light guide 2 can be pressed. The protrusion 51 is formed in a long shape so as to reach or substantially reach both ends (the front side and the opposite side of the paper surface of FIG. 7) of the terminal side portion 32C.

The planar lighting device according to the second embodiment is assembled as follows. First, in the housing frame 15C, the point light source 6 and the rod-shaped light guide 4 (see FIG.
(See reference) and the like are fitted side by side (step S1). Next, the end side portion 32C is bent outward (left side in FIG. 7), or the end side portion 32C is bent outward while the plate-shaped light guide 2 is fitted into the housing frame 15C. The internal space of the frame 15C is widened, and the plate-shaped light guide 2 is arranged in the housing frame 15C in this state (step S2). Thereafter, the outward bending of the terminal side portion 32C (left side in FIG. 7) is released (step S3).

The processing of this step S3 (end side part 32)
By releasing the bending of C), the projection 51 returns to the original state and comes into contact with the one end face 3 of the plate-shaped light guide 2 and the plate-shaped light guide 2
Is pressed to the rod-shaped light guide 4 side. At this time, the plate-shaped light guide 2 is displaced toward the rod-shaped light guide 4. Therefore, even if the plate-shaped light guide 2 is somewhat shortened due to manufacturing variations or the like, the distance M (see FIG. 15) between the plate-shaped light guide 2 and the rod-shaped light guide 4 is desired. It can be maintained at or below the value. Further, since the protrusion 51 contacts the plate-shaped light guide 2 and presses the plate-shaped light guide 2 toward the rod-shaped light guide 4, the plate-shaped light guide 2 is separated from the rod-shaped light guide 4. Direction (left direction in Figure 7)
7 is suppressed, and the displacement of the plate-shaped light guide 2 in the upward direction in FIG. 7 is suppressed by the contact force, so that the plate-shaped light guide 2 can be reliably held.

In the second embodiment (FIGS. 6 and 7), the number of the protrusions 51 formed on the inner wall surface 50 of the end side portion 32C of the housing frame 15C is one, and the end side portion is not formed. The case of a long shape reaching or substantially reaching both ends of 32C has been described as an example, but the present invention is not limited to this.
For example, as shown in FIG. 8, the housing frame 15C
On the inner wall surface 50 of the end side portion 32C of the protrusion 5
One protrusion 51A having a shorter length than that of No. 1 may be formed (third embodiment). Further, as shown in FIG. 9, the protrusions 5 are shorter than the protrusions 51 and a plurality of protrusions 5 are arranged in the longitudinal direction of the terminal side portion 32C.
1B may be formed (fourth embodiment).

In the second embodiment (FIGS. 6 and 7), the projection portion 51 protruding toward the plate-shaped light guide 2 is provided on the inner wall surface 50 of the terminal side portion 32C of the housing frame 15C.
However, instead of this, as shown in FIG. 10, the upper edge portion 2m of the plate-shaped light guide 2 is contacted with a shape protruding toward the plate-shaped light guide 2 side as shown in FIG. A possible wedge-shaped portion 52 may be formed (fifth embodiment). In this case, the wedge-shaped portion 52 is formed at both end portions of the terminal side portion 32C (see FIG.
It is formed in a long shape so as to reach or almost reach the front side and the opposite side of the 0 sheet surface.

The planar lighting device according to the fifth embodiment is assembled as follows. First, in the housing frame 15C, the point light source 6 and the rod-shaped light guide 4 (see FIG.
(See reference) and the like are fitted side by side (step S1). Next, the terminal side portion 32C is bent outward (left side in FIG. 10) to widen the internal space of the housing frame 15C, and in this state, the plate-shaped light guide 2 is arranged in the housing frame 15C.
(Step S2). Thereafter, the outward bending of the terminal side portion 32C (left side in FIG. 10) is released (step S3).

The processing of this step S3 (end side part 32)
By releasing the bending of C), the wedge-shaped portion 52 returns to the original state and comes into contact with the upper edge 2m of the plate-shaped light guide 2 to press the plate-shaped light guide 2 toward the rod-shaped light guide 4. At this time, the plate-shaped light guide 2
Is displaced to the rod-shaped light guide 4 side. Therefore, even if the plate-shaped light guide 2 is slightly shortened due to manufacturing variations or the like, the distance M between the plate-shaped light guide 2 and the rod-shaped light guide 4 is reduced.
(See FIG. 15) can be maintained at or below the desired value. Further, since the wedge-shaped portion 52 comes into contact with the plate-shaped light guide 2 and presses the plate-shaped light guide 2 obliquely from above, the upward displacement of the plate-shaped light guide 2 is surely suppressed. be able to.

In the fifth embodiment (FIG. 10), there is one wedge-shaped portion 52 formed on the inner wall surface 50 of the terminating side portion 32C of the housing frame 15C, and both ends of the terminating side portion 32C. The case where the shape is a longitudinal shape that reaches or substantially reaches the portion has been described as an example, but the present invention is not limited to this. For example, one wedge-shaped portion (not shown; see FIG. 8) having a shorter length than the wedge-shaped portion 52 is formed on the inner wall surface 50 of the terminal side portion 32C of the housing frame 15C (sixth embodiment). Form). Further, a wedge-shaped portion (not shown; see FIG. 9) having a shorter length than the wedge-shaped portion 52 and arranged in the longitudinal direction of the terminal side portion 32C is formed (seventh embodiment). You may

In the second to seventh embodiments, as shown in FIG. 11, a plurality of (two in this example) notches 36A may be formed in the terminal side portion 32C (eighth embodiment). Embodiment). According to the eighth embodiment, the terminal side portion 32C is divided by the notch 36A,
It is easy to bend outward. Therefore, when the plate-shaped light guide 2 is assembled into the housing frame 15C, the terminal side portion 32C can be easily bent, and the assemblability can be improved. it can. In the eighth embodiment, the case where the plurality of notches 36A are formed in the termination side portion 32C has been described as an example, but instead of this, 1 is formed in the termination side portion 32C.
You may make it form a notch (9th Embodiment). Further, the above-described planar lighting device of the present invention is not limited to the application to the reflection type liquid crystal display element described in the prior art, and any display element including an auxiliary lighting means including a transmission type liquid crystal element. Is applicable to.

[0042]

According to the planar lighting device of the first aspect of the present invention, the notch or hole formed in one side of the housing frame on the side away from the rod-shaped light guide and the one side are straddled. A holding member having a substantially U-shaped cross section, which is provided so as to sandwich the plate-shaped light guide, and a convex portion formed in the holding member and capable of pressing the plate-shaped light guide through the notch or hole. Therefore, when the holding member is pushed in and mounted, the convex portion presses the plate-shaped light guide through the notch or the hole. Therefore, the distance between the plate-shaped light guide and the rod-shaped light guide can be maintained at a desired value or less, even if the plate-shaped light guide is slightly shortened due to manufacturing variations or the like. Further, since the holding member is mounted and sandwiches the plate-shaped light guide member, the plate-shaped light guide member can be reliably held. Furthermore, the holding member can be removed more easily than the double-sided tape used in the prior art, so when repairing or reworking the device, the disassembling work can be performed quickly and easily, making it convenient. Become.

According to the planar lighting device of the invention described in any one of claims 2 to 4 and 8, the housing frame has flexibility, and the housing-shaped light guide member is provided in the housing frame. On the inner wall surface of the one side portion that is separated from each other, since a projection portion that protrudes toward the plate-shaped light guide body and can press the plate-shaped light guide body is formed, bend the one side portion outward. When the plate-shaped light guide is placed on the inside of the housing frame and then the bending of one side is released,
The protrusion returns to the original state and presses the plate-shaped light guide toward the rod-shaped light guide, and displaces the plate-shaped light guide toward the rod-shaped light guide. Therefore, the distance between the plate-shaped light guide and the rod-shaped light guide can be maintained at a desired value or less, even if the plate-shaped light guide is slightly shortened due to manufacturing variations or the like.
Further, since the protrusion contacts the plate-shaped light guide and presses this plate-shaped light guide toward the rod-shaped light guide, the movement of the plate-shaped light guide in the direction away from the rod-shaped light guide is suppressed. Moreover, the upward displacement of the plate-shaped light guide is suppressed by the contact force, so that the plate-shaped light guide can be reliably held.

According to the planar lighting device of the present invention as set forth in any one of claims 5 to 8, the housing frame has flexibility, and the side of the housing frame that is separated from the rod-shaped light guide is provided. On the inside wall of one side,
Since the wedge-shaped portion that can come into contact with the upper edge of the plate-shaped light guide is formed so as to protrude toward the plate-shaped light guide toward the upper side, the one side part is bent outward and the housing frame is formed. When the plate-shaped light guide is placed on the inside of the plate, and then the bending of one side is released, the wedge-shaped portion returns to the original state and the plate-shaped light guide is pressed and displaced toward the rod-shaped light guide. . Therefore, the distance between the plate-shaped light guide and the rod-shaped light guide can be maintained at a desired value or less, even if the plate-shaped light guide is slightly shortened due to manufacturing variations or the like.
Further, since the wedge-shaped portion comes into contact with the upper edge of the plate-shaped light guide and presses the plate-shaped light guide obliquely from above, it is possible to reliably hold the plate-shaped guide.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a planar lighting device according to a first embodiment of the present invention.

2 is a plan view showing the housing frame of FIG. 1. FIG.

FIG. 3 is a perspective view schematically showing a terminal side portion of the housing frame of FIG.

FIG. 4 is a view showing a cross section taken along line BB of the planar lighting device of FIG.

FIG. 5 is a plan view schematically showing a clip of a type different from the clip of FIG. 1 in comparison with a housing frame and a plate-shaped light guide.

FIG. 6 is a perspective view schematically showing a planar lighting device according to a second embodiment of the invention.

7 is a cross-sectional view showing a housing frame and a plate-shaped light guide of the planar lighting device of FIG.

FIG. 8 is a sectional view schematically showing a third embodiment of the present invention.

FIG. 9 is a sectional view schematically showing a fourth embodiment of the present invention.

FIG. 10 is a sectional view schematically showing a fifth embodiment of the present invention.

FIG. 11 is a perspective view schematically showing an eighth embodiment of the present invention.

FIG. 12 is an exploded perspective view showing an example of a conventional planar lighting device.

FIG. 13 is a perspective view of the planar lighting device including a housing frame.

14 is a plan view showing the housing frame of FIG. 13. FIG.

FIG. 15 is a diagram for explaining a problem of the conventional technique.

[Explanation of symbols]

1B planar lighting device 2 Plate-shaped light guide 15 Housing frame 32 End side (one side) 36 notches 40 clip (holding member) 45 convex

Front page continued (51) Int.Cl. ⁷ Identification code FI theme code (reference) // F21Y 101: 02 F21Y 101: 02 F term (reference) 2H091 FA23Z FA41Z FD12 FD13 FD22 LA09 LA18 5C096 AA04 AA25 BA01 BB41 CC06 CD02 CD24 CD53 DA01 FA09 FA12

Claims (8)

[Claims] 1. A substantially quadrilateral plate-shaped light guide made of a light-transmissive material, and a rod-shaped light guide made of a light-transmissive material that is arranged so as to face a side end surface of the plate-shaped light guide. A point light source arranged close to or in contact with the end face of the rod-shaped light guide, and a housing frame for accommodating and mounting the plate light guide, the rod-shaped light guide and the point light source. In the planar lighting device, a notch or a hole formed on one side of the housing frame on a side separated from the rod-shaped light guide, and the plate-shaped light guide sandwiched across the one side. A planar lighting device comprising: a holding member having a substantially U-shaped cross section; and a convex portion formed in the holding member and capable of pressing the plate-shaped light guide through the notch or hole. 2. A substantially quadrilateral plate-shaped light guide made of a translucent material, and a rod-shaped light guide made of a translucent material, which is arranged so as to face a side end surface of the plate-shaped light guide. A point light source arranged close to or in contact with the end face of the rod-shaped light guide, and a housing frame for accommodating and mounting the plate light guide, the rod-shaped light guide and the point light source. In the planar lighting device, the housing frame has flexibility, and a wall surface inside one side of the housing frame on a side separated from the rod-shaped light guide member projects toward the plate-shaped light guide member. A planar illuminating device comprising a protrusion capable of pressing a plate-shaped light guide. 3. The planar lighting device according to claim 2, wherein one or a plurality of the protrusions are formed in a longitudinal direction of the one side portion. 4. The planar lighting device according to claim 2, wherein the protrusion is formed so as to reach or substantially reach both end portions of the one side portion. 5. A substantially quadrilateral plate-shaped light guide body made of a light-transmitting material, and a rod-shaped light guide body made of a light-transmitting material that is arranged so as to face a side end surface of the plate-shaped light guide body. A point light source arranged close to or in contact with the end face of the rod-shaped light guide, and a housing frame for accommodating and mounting the plate light guide, the rod-shaped light guide and the point light source. In the planar lighting device, the housing frame has flexibility, and the inner wall surface of one side of the housing frame on the side separated from the rod-shaped light guide is closer to the plate-shaped light guide toward the upper side. A planar illuminating device having a wedge-shaped portion which is in contact with the upper edge of the plate-shaped light guide and has a protruding shape. 6. The one or more wedge-shaped portions are formed in the longitudinal direction of the one side portion.
The planar lighting device according to. 7. The planar lighting device according to claim 5, wherein the wedge-shaped portion is formed so as to reach or substantially reach both end portions of the one side portion. 8. The planar lighting device according to claim 2, wherein one or more notches are formed on the one side portion of the housing frame.