KR100734196B1 - Surface light source device and image display device - Google Patents

Abstract

The surface light source device 1 has a frame 2, and houses the light guide plate 4, the fluorescent lamp 11, and the light control members 7 to 9 in the frame 2. Light of the fluorescent lamp 11 is introduced into the light guide plate 4 from the incident surface 10, is turned in the light guide plate 4, and is gradually emitted from the exit surface 17. The emitted light is output through the light control members 7 to 9 toward an object to be irradiated such as a liquid crystal display panel. The frame 2 is provided with a pair of click portions 18, 18 that engage with the exit surface 17 at positions corresponding to both corner portions 24, 24 on the end face 16 side of the light guide plate 4. do. The light control members 7 to 9 are provided with notches 30 and 30 which avoid interference with these clicks 18 and 18. Thereby, integration of the light guide plate 4 and the frame 2 is attained, and the movement which the light guide plate 4 deviates from the frame 2 is suppressed.

Surface light source device, frame, light guide plate, image display panel

Description

Surface light source device and image display device {SURFACE LIGHT SOURCE DEVICE AND IMAGE DISPLAY DEVICE}

1 is an exploded perspective view showing a surface light source device according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating an assembling state of a frame, a reflective sheet, and a light guide plate in the surface light source device according to the first embodiment.

3 is a cross-sectional view taken along the line A-A in FIG.

4 is a plan view showing the surface light source device according to the first embodiment.

FIG. 5 is a longitudinal cross-sectional view taken along the line B-B in FIG. 4.

6 is a plan view showing a surface light source device according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view taken along the line C-C in FIG. 6.

8 is a plan view showing a surface light source device according to a third embodiment of the present invention.

9 is a cross-sectional view taken along the line D-D in FIG. 8.

Fig. 10 is a plan view showing a surface light source device according to three modifications as a fourth embodiment of the present invention, (a) is a modification of the first embodiment, (b) is a modification of the second embodiment, ( c) corresponds to the modification of 3rd embodiment, respectively.

It is a figure explaining the attachment state of the 1st-4th light control member of the surface light source device which concerns on the 1st application example of this invention.

FIG. 12 is a cross-sectional view of the click portion formed at both corner portions of the frame of the surface light source device of FIG. 11, (a) is a cross section taken along line A1-A1 in FIG. Each cross section is shown.

13 is an exploded perspective view of a conventional surface light source device.

FIG. 14 is a plan view of the conventional surface light source device shown in FIG.

15 is a longitudinal cross-sectional view taken along the line E-E in FIG. 14.

Fig. 16 is a plan view for explaining a generation state of a problem in a conventional surface light source device.

17 is a cross-sectional view taken along the line F-F in FIG. 16.

※ Explanation of codes for main parts of drawing

One … Surface light source device 2. frame

4 … Light guide plate 5. Image display panel

6. Image display apparatuses 7 to 9. Light control member

10... Entrance face 11. Fluorescent Lamp (Primary Light Source)

16. End face (side opposite to the incident face) 17.. Exit surface

18, 34, 35, 38... Click section 24... Corner

30. Notch

BACKGROUND OF THE INVENTION 1. Field of the Invention 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, various monitors, etc. in a planar shape, and an image display device including the surface light source device.

As is well known, for example, an information device such as a portable personal computer or a navigation device is provided with an image display device for displaying an image. Most commonly used in an image display apparatus is to illuminate an image display portion composed of a liquid crystal display panel or the like with the output light of the surface light source device and display an image on the display surface of the image display portion (liquid crystal display panel).

13 to 15 show a schematic structure of a surface light source device used in this type of liquid crystal display device. The surface light source device 100 shown in these figures is provided with the plastic frame 101 which accommodates several members. In the frame 101, a reflective sheet 102, a light guide plate 103, and a plurality of light control members 105 to 107 are sequentially stacked and accommodated. In the vicinity of the incident surface 108 provided by one side surface of the light guide plate 103, a fluorescent lamp 110 is received and disposed as a primary light source. On the back side of the fluorescent lamp 110, a reflector 111 for guiding the reflected light to the incident surface 108 is fixed with a screw 112. As shown in FIG.

The light control member 107 located at the uppermost side is fixed to the frame 101 by the tape 113. The uppermost light control member 107 prevents the reflection sheet 102, the light guide plate 103, and the other light control members 105, 106 from rising from the bottom surface 114 of the frame 101. have.

A liquid crystal display panel (not shown) is disposed above the surface light source device 100, and these are housed and fixed in a case (not shown) of a portable personal computer or the like.

In recent years, there has been a strong demand for thinner and lighter devices in order to increase the transportability of devices such as portable personal computers equipped with an image display device. In order to meet this demand, research has been made to reduce the thickness and weight of the frame 101 used in the surface light source device 100. Typical examples include reducing the thickness of the frame 101 and "lightening" the frame 101.

Here, "lightening" means that openings, notches, etc. are formed in a part of the frame 101 to reduce the volume of the material constituting the frame 101. When such a design is implemented, the strength of the frame 101 is lowered. This is because the frame 101 is reinforced by the case of the image display apparatus when the surface light source device 100 is incorporated into the case of the image display apparatus, so that the strength of the frame 101 does not become a problem after that.

By the way, the surface light source device 100 shown in FIGS. 13-15 is these work places (assembly place) for the integrated mounting operation of the said image display apparatus into the case, or the attachment work of the components of another image display apparatus. It is customary to be transported in a packed state. For this reason, when the strength of the frame 101 is low, the frame 101 is deformed by an external force (force applied by handling force or vibration, etc.) acting on the packaging or transportation of the surface light source device 100, As shown in FIGS. 16-17, the light guide plate 103 may jump out from the light guide plate accommodating part 115 of the frame 101 toward the image display panel accommodating part 116 side.

Such a problem may cause scratches on the light guide plate 103 or cause assembly failure of the image display apparatus. In particular, as shown in FIG. 15, a problem tends to occur when the light guide plate 103 has a wedge cross-sectional shape.

Accordingly, an object of the present invention is to provide a surface light source device in which the light guide plate does not protrude from the light guide plate accommodation portion of the frame even when an external force is applied during packaging or transportation of the surface light source device, and an image display device having the surface light source device. It is done.

The present invention firstly comprises a light guide plate having an incident surface and an end surface positioned opposite to the incident surface, a primary light source disposed to face the incident surface, and at least the light guide plate and a frame for receiving the primary light source. And a surface light source device for outputting light of the primary light source through at least the light guide plate.

According to one improvement of the present invention, the frame is provided with a pair of click portions engaged with the exit surface at positions corresponding to corner portions at both ends of the end face. This prevents the light guide plate from slipping out from the light guide plate accommodating portion of the frame when the surface light source device is packaged or transported.

Here, the surface light source device may further include a light control member housed in the frame so as to be disposed along the emission surface. In this case, preferably, the light control member is provided with a notch for avoiding interference with the pair of clicks.

Further, according to another improvement of the present invention, the frame is formed with at least a pair of click portions that engage with the exit surface to suppress the movement of the light guide plate from the frame.

Embodiment

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail, referring drawings. In addition, elements common in the various drawings are designated by the same reference numerals as appropriate.

(1) First embodiment

First, with reference to FIGS. 1-5, the surface light source device which concerns on 1st Embodiment of this invention is demonstrated. 1 to 5 are exploded perspective views showing a schematic structure of the surface light source device 1. FIG. 2 is a perspective view for explaining how the reflective sheet 3 and the light guide plate 4 are mounted on the frame 2. 3 is a cross-sectional view taken along the line A-A in FIG. 2. 4 shows the surface light source device 1 in a plan view. FIG. 5 is a cross-sectional view taken along the line B-B in FIG. 4, showing that the image display device 6 is configured by providing the image display panel 5 at a predetermined position above the surface light source device 1.

As shown in these figures, the surface light source device 1 has a frame 2 for accommodating components, in which the reflective sheet 3, the light guide plate 4, and a plurality of light control members ( 7 to 9) are sequentially stacked and accommodated. In addition, the fluorescent lamp 11 is accommodated in the frame 2 so that the fluorescent lamp 11 is disposed near the incident surface 10 provided by one side of the light guide plate 4. The fluorescent lamp 11 is a light source (primary light source) to the light guide plate 4, and is provided with a reflector 12 on its back side to guide the reflected light to the incident surface 10.

The frame 2 is composed of an injection molded body made of white synthetic resin such as PC (polycarbonate) or PMMA (methyl polymethacrylate), and has a substantially rectangular shape. The light guide plate accommodating part 13 and the image display panel accommodating part 14 are formed in the frame 2. The light guide plate accommodating portion 13 is provided with a reflecting sheet 3, a light guide plate 4, and light control members 7 to 9, and a reflector 12 equipped with a fluorescent lamp 11. The image display panel accommodating portion 14 also supports an image display panel 5 such as a liquid crystal display panel with a slight gap with respect to the surface of the uppermost light control member 9.

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 15 of the light guide plate accommodating portion 13 is made lightweight. The bottom surface 15 of the light guide plate accommodating portion 13 can support the reflective sheet 3, the light guide plate 4, and the like, and can provide control parts (not shown) of the image display panel 5, and the like. It is in the shape that there is.

And according to the characteristic of this invention, the pair of click parts 18 and 18 are formed in the frame 2. As shown in FIG. The formation position corresponds to corner portions at both ends of the end surface 16 which are side surfaces opposite to the incident surface 10 of the light guide plate 4. The click portions 18, 18 are formed to engage with the exit face 17 near the end face 16. That is, each of the click portions 18 and 18 has a substantially triangular plate shape, and the surface 20 of the light guide plate accommodation portion 13 opposite to the distal face 16 and the surface substantially orthogonal to this surface 20. It is formed over (21 or 22).

And as shown in FIG. 3, the hole 23 of the same magnitude | size as the click part 18 is formed in the bottom face 15 of the light guide plate accommodating part 13 which opposes the click part 18 at least. Accordingly, a space 25 is formed below the click portion 18 to accommodate the reflecting sheet 3 and the corner portions 24 of the light guide plate 4 (see FIG. 2).

The light guide plate 4 is formed of PC, PMMA, a cycloolefin resin material or the like which is excellent in light transmittance, and has a wedge shape in which the thickness decreases as it moves away from the fluorescent lamp 11. The shape of the exit surface (upper surface: 17) is approximately rectangular. The external dimension is designed in consideration of the difference in temperature expansion characteristics of the light guide plate 4 and the frame 2, the difference in moisture absorption expansion characteristics, the manufacturing error, and the like.

That is, under the conditions under which the surface light source device 1 is used, the end faces (sides opposite to the entrance face 10: 16) and the other side faces 26 and 27 except the entrance face 10, and these side faces 16, A slight gap is formed between the surfaces 20, 21, 22 of the light guide plate accommodating portion 13 facing the 26, 27.

In addition, unlike the reflective sheet 3 and the light control members 7 to 9, which are described later, as the flexible sheet member, the light guide plate 4 has sufficient rigidity that is not easily deformed. The optical function of the light guide plate 4 is as well known. That is, when the fluorescent lamp 11 is turned on, the light is introduced into the light guide plate 4 from the incident surface 10 and becomes internal propagated light. In the process of internal propagation, internal incidence to the exit surface 17 occurs. Here, if the incident angle at the time of internal incidence is equal to or less than the critical angle, some light is emitted from the emission surface 17. Moreover, various means for further promoting the light output from the exit surface 17 are known, and these means may be appropriately selected and adopted.

The reflective sheet 3 is a sheet member made of a resin material (for example, white PET (polyethylene terephthalate)) having excellent light reflectivity, and is provided on the side opposite to the exit surface 17 of the light guide plate 4 (lower surface: 28). As is well known, the reflective sheet 3 functions to reflect the light leaked from the lower surface 28 and return it to the light guide plate 4. The reflective sheet 3 serves as a frame 2. ) Is supported by the bottom surface 15 of the bottom face 15 and the lower surface portion 12a of the reflector 12 described later.

In the present embodiment, the light control member disposed on the exit surface 17 side of the light guide plate 4 includes a diffusion sheet (first light control member) 7 and a pair of prism sheets (second and third) in order from the inside. Light control members 8a, 8b) and a protective sheet (fourth light control member 9) having weak light diffusivity.

These light control members 7-9 are formed of the light transmissive resin material (for example, PET (polyethylene terephthalate)), and are formed in substantially rectangular shape corresponding to the shape of the exit surface 17. As shown in FIG. Moreover, each light control member 7-9 has the notch part 30 in the part corresponding to a pair of click part 18,18. As a result, interference with the pair of click portions 18 and 18 (bumping and being hindered) is avoided, and the respective light control members 7 to 9 are arranged without interruption at a predetermined position on the emission surface 17 side.

And the 3rd light control member 9 located in the uppermost side is fixed to the frame 2 with the tapes 31 and 31, and each light control member 7-9 is the light-guide plate accommodating part (of the frame 2). 13) It is to be accommodated and retained. Moreover, when notch parts 30 and 30 are not formed in each light control member 7-9, each light control member 7-9 will partially enter by the thickness of the click part 18,18. Since it is deformed and deformed, the uniformity of the luminance of the emitted light may be partially damaged. This situation does not occur in this embodiment.

Next, the reflector 12 is formed so that a cross section may become substantially U-shaped so that the light of the fluorescent lamp 11 may be reflected and guide | induced to the incident surface 10 side. As the material, for example, a sheet metal bent may be used. The vertical wall surface portion 12b and the upper surface portion 12c of the reflector 12 are accommodated in the frame 2, and the lower surface portion 12a is the reflector fixing portion 33 of the frame 2 by screws 32, 32. , 33).

And the lower surface part 12a of this reflector 12 supports the reflecting sheet 3, the light guide plate 4, and the fluorescent lamp 11 side edge part of the light control members 7-9. In addition, the lower surface portion 12a and the upper surface portion 12c support the end portions of the reflection sheet 3 and the fluorescent lamp 11 side of the light guide plate 4.

In the surface light source device 1 configured as described above, the reflector 12 having the reflection sheet 3 and the light guide plate 4 end portion (incident surface 10 side end portion) fixed to the frame 2 is fixed to the frame 2. Is supported by the upper surface portion 12c and the lower surface portion 12a of the " Then, both corner portions 24 and 24 on the end face 16 side of the reflective sheet 3 and the light guide plate 4 engage with the pair of click portions 18 and 18 formed in the frame 2.

This suppresses the light guide plate 4 from rising from the bottom surface 15 of the frame 2. For this reason, even if external force acts on the surface light source device 1, the light guide plate 4 can be reliably held in the light guide plate accommodating part 13 of the frame 2, and the light guide plate 4 has the light guide plate accommodating part 13 There is no deviation from the image display panel accommodating portion 14 side from being protruded.

Therefore, according to this embodiment, the damage to the light guide plate 4 which arises when the light guide plate 4 shifts out from the light guide plate accommodating part 13 and protrudes can be prevented. At the same time, poor assembly of the image display apparatus 6 can be prevented. In addition, the effect of preventing the floating of the light guide plate 4 is great when the cross section in which the plate thickness decreases as the light guide plate 4 moves away from the incident surface 10 (fluorescent lamp 11) is particularly wedge-shaped. The thinner the thickness of the end face 16 side of the light guide plate 4 is, the more remarkable it is.

In addition, in this embodiment, even if the frame 2 is made thinner and lighter as mentioned above and rigidity falls, the light guide plate 4 hangs on the frame via the reflector 12 and the pair of click parts 18 and 18. Since it is fitted, the frame 2 is reinforced by the light guide plate 4. Therefore, in this embodiment, even if the rigidity of the frame 2 itself is small, the component parts, such as the fluorescent lamp 11 and the light control members 7-9, can be reliably accommodated and supported. Moreover, it is also easy to reliably install the image display panel 5 and its control parts (not shown), and excessive stress does not arise in the image display panel 5 and its control parts even when an external force is applied.

In addition, it should be noted that in the present embodiment, processing for preventing injury from the frame 2 of the light guide plate 4 is performed only on the frame 2 side, and the light guide plate 4 does not require any special processing. to be. That is, the pair of click portions 18, 18 are formed in a part of the frame 2, while the light guide plate 4 is not provided with engaging projections, recesses, or the like. If projections or recesses are formed in the light guide plate 4, abnormal light emission may be caused. In this embodiment, there is no such concern.

The abnormal light emission herein refers to a phenomenon in which edge portions of protrusions and concave portions formed on the light guide plate are shined brighter than other parts, and this is observed as a local excess luminance part on the upper side of the light exit plate of the light guide plate. Needless to say, light emission lowers the illumination quality.

Another thing to note in this embodiment is that two places of the corner parts 24 and 24 of the end surface 16 side of the light guide plate 4 are engaged with the click parts 18 and 18, respectively. As a result, the light guide plate 4 and the frame 2 are more reliably integrated as compared with the case where only one of the corner portions 24 and 24 is engaged with the click portion 18.

That is, if the configuration in which only one portion of the corner portions 24 and 24 on the end face 16 is engaged with the click portion 18 is adopted, a case such as a portable transportation of the surface light source device 1 or a portable personal computer or the like is employed. The frame 2 tends to be deformed at the corner portion 24 side where it is not engaged with the click portion 18 when mounting on the. Then, a large gap is likely to occur between the light guide plate 4 and the frame 2 or between the light guide plate 4 and the reflective sheet 3, and foreign matter may enter the gap and cause deterioration of the lighting quality. There is. In this embodiment, there is no such concern.

(2) 2nd Embodiment

The characteristic of this embodiment is shown by FIG. 6, FIG. The configuration and various functions of other parts are the same as in the first embodiment. Therefore, description is given focusing on the characteristic of this embodiment, and repeated description is abbreviate | omitted.

As depicted in FIGS. 6 and 7, in the surface light source device 1 according to the present embodiment, corner portions 24 corresponding to both ends of the end surface 16 in the exit surface 17 of the light guide plate 4 are provided. The rectangular plate-shaped click portions 34 and 34 engaged with each other are protruded from the surface 20 of the frame 2 facing the end face 16 at the same place.

Then, a space 25 for accommodating the reflection sheet 3 and the light guide plate 4 is formed below the pair of click portions 34 and 34. In addition, each light control member 7-9 is notched in part corresponding to a pair of click part 34,34, and is arrange | positioned without a trouble in the predetermined position by the exit surface 17 side of the light guide plate 4, have.

Thus, in this embodiment, the structure of 1st Embodiment and the various actions accompanying it except the point which click part 34 and 34 are employ | adopted instead of the click part 18 and 18 in 1st Embodiment. This is kept by default. Therefore, needless to say, the same effects as in the first embodiment can be obtained in the present embodiment.                     

(3) Third Embodiment

Features of this embodiment are shown in Figs. 8 and 9. The configuration and various functions of other parts are the same as in the first or second embodiment. Therefore, description is given focusing on the characteristic of this embodiment, and repeated description is abbreviate | omitted.

In the surface light source device 1 according to the present embodiment, as shown in FIGS. 8 to 9, rectangular plate-shaped click portions 35 and 35 protrude to the surfaces 21 and 22 of the frame 2. The formation position is a portion close to the corner portions 24 and 24 corresponding to both ends of the distal end face 16 at the exit face 17 of the light guide plate 4, and the click parts 35 and 35 are engaged at the same part. do.

Then, a space 36 for accommodating the reflection sheet 3 and the light guide plate 4 is formed below the pair of click portions 35 and 35. In addition, the part corresponding to the pair of click parts 35 and 35 is notched in each light control member 7-9. Thereby, the light control members 7-9 are arrange | positioned without interruption in the predetermined position on the emission surface 17 side.

Thus, in this embodiment, the structure of 1st Embodiment and the various action | compatibility accompanying it except the point which click part 35 and 35 are employ | adopted instead of the click part 18 and 18 in 1st Embodiment. This is kept by default. Therefore, needless to say, the same effects as in the first embodiment can be obtained in the present embodiment.

(4) Fourth Embodiment

The characteristic of this embodiment is shown by FIG.10 (a)-FIG.10 (c). The configuration and various functions of other parts are the same as in the first or third embodiment. Therefore, description is given focusing on the characteristic of this embodiment, and repeated description is abbreviate | omitted.

In the surface light source device 1 according to the present embodiment, as shown in FIGS. 10A to 10C, the click portions 18 and 18 employed in the first embodiment and the second embodiment are employed. In addition to the click portions 34 and 34 or the click portions 35 and 35 employed in the third embodiment, the click portions 38 and 38 protrude from the surfaces 21 and 22 of the frame 2.

This formation position corresponds to portions 37 and 37 near the incidence surface of the exit surface 17 of the light guide plate 4, and the click portions 38 and 38 are engaged with the same portions 37 and 37. As shown in FIG.

A space for accommodating the reflective sheet 3 and the light guide plate 4 is formed below each of the click portions 38 and 38. The light control members 7 to 9 are notched in portions corresponding to the click portions 18, 34, 35, and 38, and do not interfere with a predetermined position on the exit surface 17 side of the light guide plate 4. It is supposed to be arranged.

Thus, in this embodiment, except that the click parts 38 and 38 are employ | adopted in addition to the click parts 18, 34, 35 in 1st-3rd embodiment, 1st-3rd embodiment The composition of and its accompanying actions are basically maintained. Therefore, needless to say, the same effects as in these embodiments can be obtained in the present embodiment.

Moreover, the surface light source device 1 which concerns on this embodiment supports the light guide plate 4 and the reflection sheet 3 with the reflector 12, and when it is difficult to fix to the frame 2, the incident surface of the light guide plate 4 The click portions 38 and 38 engaged with the vicinity portion 37 can suppress the light guide plate 4 from rising from the frame 2.

As mentioned above, although 1st-4th embodiment was described, these are not the meaning which limits this invention. Note the following points concerning these embodiments.

(i) In each of the above-described embodiments, the light emitted from the exit surface 17 of the light guide plate 4 is diffused by the first light control member 7 to achieve uniform luminance distribution, and then the second and third light. The control materials 8a and 8b change the traveling direction of the light in the normal direction of the emission surface 17 of the light guide plate 4 to increase the ratio of light that can be effectively used for illumination. The light control member 8a, 8b is a member which formed many prism rows as a well-known aspect, and the extending direction of the prism row differs by almost 90 degrees from the light control member 8a, 8b.

The fourth light control member 9 is mainly used as a protective sheet for preventing scratches of the prism face of the light control member 8b, but a function as a diffusion sheet for achieving evenness of illumination light is further provided as necessary. do.

However, the arrangement and use of such a light control member are merely examples. For example, the second light control member 8a may be omitted in the case where the same prism surface as the prism surface of the second light control member 8a is formed on the lower surface 28 of the light guide plate 4.

Generally, as a specific structure of the light guide plate 4 and the light control members 7-9, the various structures conventionally known in this kind of surface light source device 1 can be employ | adopted.

(ii) In the present invention, the click portions 18, 34, 35, 38 for preventing the light guide plate 4 from rising from the bottom surface 15 of the frame are not limited to those shown in the above embodiments. As long as the function is maintained, the shape may be changed, the formation position may be appropriately shifted, or the number of formation may be appropriately changed.

(iii) In each of the above embodiments, the light generating members 7 to 9 may interfere with each of the click portions 18, 34, 35, 38 so as not to use the portion for generating the luminance change for illumination. Moreover, even if there exists a part which produces a brightness change by each light control member 7-9 interfering with each click part 18, 34, 35, 38, there may be a case where it does not become a problem in illumination. In such a case, it is not necessary to form the notch part 30 in each light control member 7-9.

(iv) The cross-sectional shape of the light guide plate may not be a wedge shape. For example, a light guide plate of substantially uniform thickness throughout may be employed. Moreover, you may use the other light-guide plate of cross-sectional shape.

(5) Other Modified Embodiments

 11 shows an application example of the first embodiment. As shown in the figure, the notch portions 30 and 30 are disposed at both corner portions of the first light control member 7 and the second light control member 8a so as not to interfere with the click portions 18 and 18 of the frame 2. ) Is formed. Moreover, the notch part 30 is formed in the right corner part of the figure of the 3rd light control member 8b.

The notches are not formed at both corners of the fourth light control member 9 at all. On the other hand, the thickness T1 of the left click part 18 in the figure in the click parts 18 and 18 of both corner parts of the frame 2 is the first and second light control as shown in Fig. 12A. It is formed in the thickness dimension equivalent to the thickness of two sheets of members 7 and 8a.

In addition, the thickness T2 of the right click part 18 in FIG. 11 is formed in the thickness dimension equivalent to the thickness of the 1st-3rd light control member, as shown to FIG. 12 (b).

With this configuration, the notch portion 30 can be distinguished from the second light control member 8a and the third light control member 8b, which are difficult to distinguish during assembly work or the like. That is, the second light control member 8a and the third light control member 8b are formed to have almost 90 degrees in the direction of forming the prism face, but the pitch of the prism face is extremely small because the pitch of forming the prism face is extremely small. It was difficult to distinguish the two from each other, and there was a fear that the order would be mistaken for mounting.

However, when the second light control member 8a and the third light control member 8b are distinguished with or without the notch portion 30 as described above, the second light control member 8a and the third light control member The problem that (8b) is incorrectly mounted can be prevented in advance.

Moreover, the 1st light control member 7 and the 4th light control member 9 which are similar in both characteristics can also be distinguished easily with or without the notch part 30. FIG. The first light control member 7 and the second light control member 8a have the same notch portions 30 as described above, but the surface light source device 1 is clearly different in both properties. The workers involved in the assembly work of the team do not mistake them.

According to the above-described application example, the first to fourth light control members 7 to 9 can be correctly mounted in order without being mistaken. In addition, the notch part 30 is not limited to the above-mentioned aspect as long as it is formed selectively suitably so that the 1st-4th light control members 7-9 may be distinguished, and also the thickness of the click part 18, 18 is carried out. T1 and T2 may also be appropriately changed depending on the formation state of the notch portion 30.

As described above, in the surface light source device according to the present invention, since the click portion engaged with the emission surface side of the light guide plate is formed in the frame, the click portion can suppress the light guide plate from rising from the frame. Even when acting on the surface light source device, the light guide plate does not deviate from the frame and protrudes, and damage to the light guide plate due to the light guide plate deviating from the frame can be prevented.

In addition, when the image display device is formed by attaching the image display panel to the surface light source device according to the present invention, the light guide plate is prevented from rising from the frame by the click portion formed in the frame, and the light guide plate is shifted from the frame. Since it does not protrude, it does not cause assembly failure of the image display apparatus.

Claims (6)

 A light guide plate having an incidence surface and an end surface positioned opposite to the incidence surface, a primary light source disposed to face the incidence surface, a light control member disposed along an exit surface of the light guide plate, at least the light guide plate, the A frame for receiving a primary light source and the light control member, In the surface light source device for outputting the light of the primary light source at least through the light guide plate and the light control member, The frame is provided with a pair of click portions engaged with the exit surface of the light guide plate at positions corresponding to corner portions at both ends of the end face. The light control member has a notch portion for avoiding interference with the pair of click portions only at a position corresponding to the pair of click portions. delete A light guide plate having an incidence surface and an end surface positioned opposite to the incidence surface, a primary light source disposed to face the incidence surface, a light control member disposed along an exit surface of the light guide plate, at least the light guide plate, the A frame for receiving a primary light source and the light control member, In the surface light source device for outputting the light of the primary light source at least through the light guide plate and the light control member, The frame is formed with at least a pair of click portions that engage with the exit surface of the light guide plate to suppress the movement of the light guide plate from the frame. The light control member has a notch portion for avoiding interference with the pair of click portions only at a position corresponding to the at least one pair of click portions. An image display apparatus having a surface light source device and an image display panel illuminated by the output light of the surface light source device, The surface light source device includes: a light guide plate having an incidence surface and an end surface positioned opposite to the incidence surface, a primary light source disposed to face the incidence surface, and a light control member disposed along the emission surface of the light guide plate; And a frame for receiving at least the light guide plate, the primary light source and the light control member, wherein the light of the primary light source is output through at least the light guide plate and the light control member. The frame is provided with a pair of click portions engaged with the exit surface of the light guide plate at positions corresponding to corner portions at both ends of the end face. And the light control member has a notch portion for avoiding interference with the pair of click portions only at a position corresponding to the at least one pair of click portions. delete An image display apparatus comprising a surface light source device and an image display panel illuminated by output light of the surface light source device. The surface light source device includes: a light guide plate having an incidence surface and an end surface positioned opposite to the incidence surface, a primary light source disposed to face the incidence surface, and a light control member disposed along the emission surface of the light guide plate; A frame for receiving at least the light guide plate, the primary light source and the light control member, the light of the primary light source being output through at least the light guide plate and the light control member, The frame is provided with at least one pair of click portions that engage with the exit surface of the light guide plate to suppress the movement of the light guide plate from the frame. And the light control member has a notch portion for avoiding interference with the pair of click portions only at a position corresponding to the at least one pair of click portions.

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