JP6478468B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device.

  In recent years, a backlight device for a liquid crystal display has been developed using a light emitting diode (LED) as a light source, and a further increase in luminance and a reduction in thickness are required.

  For example, Patent Document 1 (see FIGS. 8 to 12) includes a light guide plate having an incident surface on the side surface, and a light source unit having a flexible substrate, and the flexible substrate includes a plurality of mounting areas, and The mounting surface of the plurality of mounting regions is bent in a portion other than the portion to be the mounting region so that the mounting surface of the plurality of mounting regions is parallel to the main surface of the light guide plate. A side-light type backlight device is described in which the light-emitting elements of (1) are mounted in a row with the emission direction facing the incident surface.

WO2006 / 027883

  However, in the backlight device described in Patent Document 1, the light of the light emitting element easily leaks in the direction opposite to the emission direction.

  Then, this invention is made in view of this situation, and it aims at providing the light-emitting device which can be thinned, being excellent in the utilization efficiency of the light which a light source emits.

  In order to solve the above problems, a light emitting device according to the present invention comprises a first substrate portion, a second substrate portion facing the first substrate portion, and a space between the first substrate portion and the second substrate portion. A light source device mounted on at least one inner surface of a flexible wiring board bent so as to include an intermediate substrate portion, the first substrate portion, the second substrate portion, and the intermediate substrate portion And the intermediate substrate portion has a light reflecting member other than the wiring, and is provided on the side opposite to the main light emitting surface of the light emitting device.

  According to the present invention, it is possible to obtain a light emitting device that can be thinned while having excellent utilization efficiency of light emitted from the light source.

A schematic front view (a) of a light emitting device according to an embodiment of the present invention, a schematic cross sectional view (b) showing an enlarged cross section of the light emitting device, and a flexible wiring board before bending in the light emitting device It is a schematic plan view (c) which shows arrangement | positioning of the upper light source device. A schematic front view (a) of a light emitting device according to an embodiment of the present invention, a schematic cross sectional view (b) showing an enlarged cross section of the light emitting device, and a flexible wiring board before bending in the light emitting device It is a schematic plan view (c) which shows arrangement | positioning of the upper light source device. A schematic front view (a) of a light emitting device according to an embodiment of the present invention, a schematic cross sectional view (b) showing an enlarged cross section taken along the line C-C, and a flexible wiring board before bending in the light emitting device It is a schematic plan view (c) which shows arrangement | positioning of the upper light source device. A schematic front view (a) of a light emitting device according to an embodiment of the present invention, a schematic cross sectional view (b) showing an enlarged cross section of the light emitting device, and a flexible wiring board before bending in the light emitting device It is a schematic plan view (c) which shows arrangement | positioning of the upper light source device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. However, the light emitting device described below is for embodying the technical concept of the present invention, and the present invention is not limited to the following unless there is a specific description. Also, the contents described in one embodiment can be applied to the other embodiments. Note that the sizes and positional relationships of members shown in each drawing may be exaggerated for the sake of clarity. Hereinafter, the “x” direction shown in the drawings is a lateral direction or side, the “y” direction is a vertical direction or a thickness direction, and the “z” direction is a front-rear direction.

Embodiment 1
FIG. 1 (a) is a schematic front view of the light emitting device 100 according to the first embodiment, and FIG. 1 (b) is a schematic cross-sectional view showing the AA cross section in FIG. 1 (c) is a schematic plan view showing the arrangement of the light source device on the flexible wiring substrate before bending in the light emitting device 100. FIG.

  As shown in FIGS. 1A to 1C, the light emitting device 100 is a laterally long light emitting device having a main light emitting surface 101 at the front. The light emitting device 100 includes a flexible wiring substrate 10 and a first light source device 20. The flexible wiring substrate 10 includes a first substrate portion 11, a second substrate portion 12 facing the first substrate portion 11, and an intermediate substrate portion 13 between the first substrate portion 11 and the second substrate portion 12. , Is folded to include. The light source device 20 is mounted on the inner surface of the first substrate unit 11. Hereinafter, the light source device mounted on the inner surface of the first substrate unit 11 will be referred to as “first light source device”. The intermediate substrate portion 13 of the flexible wiring substrate has a light reflecting member 16 other than the wiring 15. The intermediate substrate portion 13 of the flexible wiring substrate is provided on the side opposite to the main light emitting surface 101 of the light emitting device.

  Thus, in the light emitting device 100, the flexible wiring board 10 on which the first light source device 20 (also the second light source device 22 described later) is mounted is shown in FIG. (The other embodiments are the same as in the following), and by forming a U-shape in a cross sectional view, a light source container open in the forward and lateral directions (that is, the front and the left and right sides) is formed in a pseudo manner . Therefore, the intermediate substrate portion 13 of the flexible wiring substrate can suppress light leakage to the rear of the light emitting device. In addition, light emitted from the first light source device 20 can be reflected forward by the light reflective member 16 in the intermediate substrate portion 13 of the flexible wiring substrate and efficiently extracted from the main light emitting surface 101. Furthermore, in addition to the first substrate unit 11 on the mounting side of the first light source device 20, the second substrate unit 12 can also suppress leakage of light emitted by the first light source device 20 in the vertical direction of the light emitting device. As described above, the light emitting device 100 can be a light emitting device that can be thinned while having excellent utilization efficiency of light emitted from the light source (light source in the light source device). In addition, it is possible to suppress unintended light emission from the light emitting device 100 and to suppress generation of stray light.

  In the light emitting device 100 of the illustrated example, the flexible wiring substrate 10 sequentially includes the wiring 15 and the light reflective member 16 on the base 14. Thus, in the first substrate portion 11, the second substrate portion 12, and the intermediate substrate portion 13, the light reflective member 16 is configured to be light reflective in that it constitutes the inner surface (the outermost surface) of each of these portions. Although it is preferable from the viewpoint, the effect of suppressing the light leakage can be exhibited regardless of whether it is inside or outside each of these parts. Further, in the light emitting device 100 in the illustrated example, there are a plurality of first light source devices 20 (also second light source devices 22 described later), which are arranged in the lateral direction of the light emitting device.

  Hereinafter, a preferred embodiment of the light emitting device 100 will be described.

  As shown in FIGS. 1A and 1C, in the light emitting device 100, the light source device 20 on the inner surface of the first substrate portion 11 of the flexible wiring substrate and the light source device on the inner surface of the second substrate portion 12 22 are each implemented. Hereinafter, the light source device mounted on the inner surface of the second substrate unit 12 will be referred to as a “second light source device”. When the light emitting device 100 is viewed from the main light emitting surface 101 side, the first light source device 20 and the second light source device 22 are disposed so as not to face each other in the vertical direction. That is, the first light source device 20 and the second light source device 22 are disposed laterally offset so as not to overlap each other. Thus, the light emitting device 100 can be easily formed thin. In addition, the mounting interval of the light source device on the flexible wiring substrate 10 can be increased compared to the case where the same number of light source devices are mounted on only one of the first substrate portion 11 and the second substrate portion 12. The heat dissipation of can be enhanced. Furthermore, when the same number of light source devices are mounted on only one of the first substrate portion 11 and the second substrate portion 12, the restriction of the width and / or the spacing of the wiring 15 received can be avoided, Easy to place. In addition, in this example, although the 1st light source device 20 and the 2nd light source device 22 are arrange | positioned so that it may be alternately located in a line with the horizontal direction, it does not restrict to this.

  As shown in FIG. 1B, in the light emitting device 100, the first substrate portion 11 and the second substrate portion 12 of the flexible wiring substrate have the light reflecting members 16 other than the wiring 15. Thereby, the light emitted from the first light source device 20 and / or the second light source device 22 can be efficiently reflected by the light reflective member 16. Therefore, leakage of light emitted from the first light source device 20 and / or the second light source device 22 in the vertical direction of the device can be further suppressed, and light emitted from the first light source device 20 and / or the second light source device 22 Can be efficiently extracted from the main light emitting surface 101. Although it is preferable that both the first substrate unit 11 and the second substrate unit 12 have the light reflective member 16 as in this example, one of the first substrate unit 11 and the second substrate unit 12 is used. One of them may have the light reflective member 16. The light reflective members 16 provided on the first substrate unit 11, the second substrate unit 12, and the intermediate substrate unit 13 may be different from each other, although they are simple and preferable to be the same.

  As shown in FIGS. 1A to 1C, in the light emitting device 100, the first light source device 20 and the second light source device 22 are side-emitting type LED packages. The side surface light emitting type LED package can efficiently emit light in one direction parallel to the mounting surface by itself and can be formed on the inner surface of the first substrate portion 11 and / or the second substrate portion 12 of the flexible wiring substrate. When mounted, highly efficient light emission to the main light emitting surface 101 side is possible. However, the amount of light emitted from the package in the vertical and backward directions is also small, and such light leakage is suppressed by the first substrate portion 11, the second substrate portion 12, and the intermediate substrate portion 13 of the flexible wiring substrate. Thus, light leakage in the vertical direction and the rear direction of the light emitting device can be effectively suppressed.

  As shown in FIGS. 1A and 1B, in the light emitting device 100, the distance (maximum value) between the inner surface of the first substrate unit 11 and the inner surface of the second substrate unit 12 is the first light source device 20. It is twice or less the thickness of (the second light source device 22 may be). Thus, the light emitting device 100 can be easily formed thin. In particular, the distance between the inner surface of the first substrate unit 11 and the inner surface of the second substrate unit 12 can be approximately the thickness of the first light source device 20 (which may be the second light source device 22). In that case, the upper surface (top surface) of the first light source device 20 may be in contact with the inner surface of the second substrate unit 12 and / or the upper surface (top surface) of the second light source device 22 may be in contact with the inner surface of the first substrate portion 11 . More strictly, the “thickness of the first light source device 20 (or the second light source device 22)” may include the thickness of an adhesive such as solder.

  As shown in FIG. 1A, in the light emitting device 100, when the light emitting device 100 is viewed from the main light emitting surface 101 side, the first light source device 20 and the second light source device 22 which are side light emitting type LED packages The width of the main surface on the mounting side (bottom surface of the package) is larger than the width of the main surface on the opposite side to the mounting side (top surface of the package). Thereby, when the flexible wiring board 10 is bent, the first light source device 20 and the second light source device 22 interfere with each other, or the first light source device 20 or the second light source device 22 such as solder It is easy to avoid interference of the adhesive, and it is easy to arrange the first light source device 20 and the second light source device 22 densely.

  As shown in FIGS. 1 (a) and 1 (b), in the light emitting device 100, an electric circuit for covering the first light source device 20 and the second light source device 22 between the first substrate portion 11 and the second substrate portion 12 An insulating covering member 30 is provided. Thus, the first light source device 20 and the second light source device 22 can be stably held on the flexible wiring board 10. Further, damage due to interference between the first light source device 20 and the second light source device 22 and / or an electrical short can be suppressed or avoided. Furthermore, the first substrate unit 11 and the second substrate unit 12, the first light source device 20 and the second substrate unit 12, the second light source device 22 and the first substrate unit 11, the first light source device 20 and the second light source device 22 etc. Can be glued together. Although the covering member 30 may be provided in a part between the first substrate unit 11 and the second substrate unit 12, the covering member 30 may be provided between the first substrate unit 11 and the second substrate unit 12 as in this example. It is preferable to be filled so as to fill substantially all of the voids. The same applies to the covering member 32 described later.

  As shown in FIG. 1 (b), in the light emitting device 100, the covering member 30 contains a filler 35. Thereby, the covering member 30 can be provided with various functions. For example, if the filler 35 is a substance having high thermal conductivity, the covering member 30 can be functioned as a heat dissipation grease to enhance the heat dissipation of the first light source device 20 and / or the second light source device 22. In this case, the filler 35 may be metal as long as it is a range that can avoid an electrical short of the light source device and / or the wiring 15. Examples of the metal filler 35 include silver, copper, and alloys of these. Further, for example, if the filler 35 is a substance having high light reflectivity such as a white pigment, the front luminance of the light emitting device 100 can be increased. Further, for example, if the filler 35 is a substance having a high light shielding property such as a black pigment, the light emission area for each light source device can be highlighted, reflection of return light and / or extraneous light on the main light emission surface 101 side can be suppressed, can do.

  As shown in FIGS. 1A to 1C, in the light emitting device 100, the light source device is not mounted on the intermediate substrate portion 13 of the flexible wiring substrate. Thereby, the flexible wiring substrate 10 can be easily bent by the intermediate substrate portion 13, and the light emitting device 100 can be easily formed thin. However, the present invention is not limited to this, and for example, the light source device may be mounted also on the intermediate substrate portion 13 of the flexible wiring substrate in order to achieve high luminous flux (see Embodiment 4 described later). In addition, a semiconductor device other than the light source device such as a protective element may be mounted on the intermediate substrate portion 13 of the flexible wiring substrate. As a protective element, a Zener diode is mentioned, for example.

  Although the shape of the intermediate substrate portion 13 of the flexible wiring substrate is not particularly limited, in the light emitting device 100, as shown in FIG. 1B, the intermediate substrate portion 13 of the flexible wiring substrate is curved. . As a result, the fatigue of the intermediate substrate portion 13 of the flexible wiring substrate can be reduced, and the occurrence of breakage of the wiring 15 and peeling of the light reflective member 16 can be suppressed or avoided. In addition, if the intermediate substrate portion 13 of the flexible wiring substrate is angularly bent, such as when the flexible wiring substrate 10 is bent in a V shape in cross section, the intermediate substrate portion 13 and thus the light emitting device 100 can be miniaturized. Can be formed. In addition, when the light source device and / or another semiconductor device is mounted on the intermediate substrate portion 13 of the flexible wiring substrate, the flexible wiring substrate 10 may include a flat region at the center of the intermediate substrate portion 13 ( For example, if it is bent in a U-shape in cross section, it is easy to arrange the light source device and / or other semiconductor devices in the flat region (refer to the fourth embodiment described later, particularly FIG. 4B). In addition, although the shape after bending of such a flexible wiring substrate 10 can be maintained by the presence of the wiring 15, a supporting member for supporting the flexible wiring substrate 10 is provided to make it easier to maintain. It may be done. The support member may be a support (such as a case or a bracket) for supporting the outer surface of the flexible wiring substrate 10, or may be a dummy mounting formed on the flexible wiring substrate 10 and electrically insulated from the wiring 15. It may be a (dummy) wiring or a metal film.

Second Embodiment
Fig.2 (a) is a schematic front view of the light-emitting device 200 which concerns on Embodiment 2, FIG.2 (b) is a schematic sectional drawing which expands and shows the BB cross section in FIG. 2 (a), and is a figure. 2 (c) is a schematic plan view showing the arrangement of the light source device on the flexible wiring substrate before bending in the light emitting device 200. FIG.

  The light emitting device 200 according to the second embodiment includes the bent shape of the flexible wiring board, the point that the second light source device (the second light source device 22 in the first embodiment) is not provided, and the first light source device The light emitting device 100 is common to the light emitting device 100 according to the first embodiment in the other points, unlike the light emitting device 100 according to the first embodiment in terms of the shape of the light emitting device 100. Although the light emitting device 200 in the illustrated example is not provided with the covering member (the covering member 30 in the first embodiment), the present invention is not limited to this, and a covering member may be provided.

  As shown in FIGS. 2A to 2C, the light emitting device 200 is a laterally long light emitting device having a main light emitting surface 201 at the front. Although the light emitting device 200 has a smaller number of light source devices than the light emitting device 100 of the first embodiment, the light emitting device 200 is simpler in structure and easier to form than the light emitting device 100 of the first embodiment. In the light emitting device 200, the first light source device 23 is mounted on the inner surface of the first substrate portion 11 of the flexible wiring board, and the light source device is not mounted on the inner surface of the second substrate portion 12. The second substrate unit 12 is provided to cover the first light source device 23. The inner surface of the second substrate unit 12 may be in contact with the upper surface of the first light source device 23 and may be adhered to the upper surface of the first light source device 23 by an adhesive or the covering member 30 in the first embodiment. Also in the present example, the first substrate unit 11 and / or the second substrate unit 12 includes the light reflective member 16 other than the wiring 15 so that the light emitting device in the vertical direction of the light emitted by the first light source device 23 Can be further suppressed, and the light emitted from the first light source device 23 can be efficiently extracted from the main light emitting surface 201. When the light emitting device 200 is viewed from the main light emitting surface 201 side, the width of the main surface on the mounting side (bottom surface of the package) in the first light source device 23 is the main surface on the opposite side to the mounting side (package It is almost the same as the width of the sky).

  In the light emitting device 100 according to the first embodiment, light extraction in the lateral direction is promoted as a pseudo light source container in which the flexible wiring substrate 10 is opened in the lateral direction. On the other hand, in the light emitting device 200, as shown in FIGS. 2A and 2C, the flexible wiring board 17 has the side wall portion 18. As shown in FIG. As described above, the flexible wiring board 10 in the light emitting device 100 can be obtained by using the flexible wiring board 10 as a pseudo light source container closed in the horizontal direction (left and right sides) in addition to the upper and lower portions and the rear. The frontal brightness can be increased compared to the form of. In the present example, the side wall portion 18 is provided continuously to the end of the second substrate portion 12 and bent to the first substrate portion 11 side, but is continuous to the end of the first substrate portion 11 , And may be bent to the second substrate 12 side, or may be formed continuously to the end of the intermediate substrate 13 and bent to the main light emitting surface 201 (forward). It is also good. In addition, in order to reduce a gap between the side wall portion 18 and the first substrate portion 11, the second substrate portion 12, or the intermediate substrate portion 13, a fold-off portion which is bent along the main surfaces of these portions. May be included. Preferably, the side wall portion 18 also has a light reflective member 16 other than the wiring 15.

Embodiment 3
Fig.3 (a) is a schematic front view of the light-emitting device 300 which concerns on Embodiment 3, FIG.3 (b) is a schematic sectional drawing which expands and shows the CC cross section in FIG. 3 (a), and is a figure. 3 (c) is a schematic plan view showing the arrangement of the light source device on the flexible wiring substrate before bending in the light emitting device 300. FIG.

  The light emitting device 300 according to the third embodiment is different from the light emitting device 100 according to the first embodiment in the form of the light source device, and is common to the light emitting device 100 according to the first embodiment in the other points. The light emitting device 300 in the illustrated example is not provided with the covering member (the covering member 30 in the first embodiment), but is not limited to this and may be provided with a covering member.

  As shown in FIGS. 3A to 3C, the light emitting device 300 is a laterally long light emitting device having a main light emitting surface 301 at the front. In the light emitting device 300, the first light source device 25 and the second light source device 26 are side light emitting type LED packages having a form different from those of the first and second embodiments. In this LED package, the LED chip is flip-chip mounted on the wiring substrate, and the side is a light-reflective encapsulation member, and the front is a light-transmissive member (in this example, it may be omitted to contain a phosphor) Is coated with The same material as the covering member 30 can be used as a base material of the covering member and the light transmitting member, and the covering member may contain a white pigment such as titanium oxide. The first light source device 25 and the second light source device 26 can be formed thinner than an LED package in which the LED chip is housed in a package having a recess. Therefore, the light emitting device 300 can be easily formed thinner than the light emitting device 100 of the first embodiment. However, since the package is not provided, the light emitted from the first light source device 25 and the second light source device 26 (especially the light transmitting member) in the vertical and backward directions is relatively large, but such light leakage is By restraining by the first substrate portion 11, the second substrate portion 12, and the intermediate substrate portion 13 of the flexible wiring substrate, it is possible to suppress the leakage of light in the vertical direction and the rear direction of the light emitting device. Moreover, also in this example, the first light source device 25 and / or the second light source device are provided by the first substrate portion 11 and / or the second substrate portion 12 having the light reflective member 16 other than the wiring 15. Leakage of light emitted by the light source 26 in the vertical direction of the light emitting device can be further suppressed, and light emitted from the first light source device 25 and / or the second light source device 26 can be efficiently extracted from the main light emitting surface 301.

Fourth Preferred Embodiment
FIG. 4 (a) is a schematic front view of a light emitting device 400 according to the fourth embodiment, and FIG. 4 (b) is a schematic cross-sectional view showing an enlarged DD cross section in FIG. 4 (a). 4 (c) is a schematic plan view showing the arrangement of the light source device on the flexible wiring substrate before bending in the light emitting device 400. FIG.

  The light emitting device 400 according to the fourth embodiment differs from the light emitting device 100 according to the first embodiment in the form of the light source device and in the form of the covering member, and in the other points according to the first embodiment. It is common to the light emitting device 100. The light emitting device 400 of the illustrated example is mounted on the inner surface of the intermediate light source device 29 (on the inner surface of the intermediate substrate portion 13) in terms of the relationship between the distance between the first substrate portion and the second substrate portion and the thickness of the light source device. Is different from the light emitting device 100 according to the first embodiment, but the present invention is not limited to this, and may be the same as the light emitting device 100.

  As shown in FIGS. 4A to 4C, the light emitting device 400 is a laterally long light emitting device having a main light emitting surface 401 in front. In the light emitting device 400, the first light source device 27 on the inner surface of the first substrate portion 11 of the flexible wiring board, the second light source device 28 on the inner surface of the second substrate portion 12, and the inner surface of the intermediate substrate portion 13. The third light source devices 29 are mounted respectively. The first light source device 27, the second light source device 28, and the third light source device 29 are LED chips. Between the first substrate unit 11 and the second substrate unit 12, an electrically insulating and translucent covering member 32 covering the first light source device 27, the second light source device 28, and the third light source device 29 is provided. It is provided. The covering member 32 contains a phosphor 37. With such a configuration, one linear light emission can be obtained with substantially the entire region between the first substrate unit 11 and the second substrate unit 12 as a light source region. The phosphor 37 is not necessarily required and can be omitted. In the illustrated light emitting device 400, there are also a plurality of third light source devices 29, which are arranged in the lateral direction of the light emitting device, but at least one may be provided.

  As shown in FIGS. 4A and 4B, in the light emitting device 400, the distance (maximum value) between the inner surface of the first substrate unit 11 and the inner surface of the second substrate unit 12 is the first light source device 27. It is larger than twice the thickness of (the second light source device 28 may be). When the first light source device 27 and / or the second light source device 28 are LED chips, the luminance tends to be high in the vicinity of the light source device. For this reason, the distance between the inner surface of the first substrate portion 11 and the inner surface of the second substrate portion 12, ie, the thickness of the covering member 32, is made relatively large to diffuse the light emitted from the LED chip, and the main light emission It is preferable to take out from the surface 401. Moreover, although the fluorescent substance 37 contained in the covering member 32 can be functioned also as a light diffusing agent, you may make the covering member 32 separately contain a filler as a light diffusing agent. Although the upper limit value of the distance between the inner surface of the first substrate unit 11 and the inner surface of the second substrate unit 12 is not particularly limited, for example, the thickness of the first light source device 27 (may be the second light source device 28) In order to make the light emitting device thinner, it is preferably 5 times or less, more preferably 3 times or less. Further, from the viewpoint of thinning the light emitting device, the third light source device 29 may use an LED chip which is long in the lateral direction and short in the vertical direction.

  As shown in FIG. 4B, in the light emitting device 400, the inner surface of the bending region continuous with the first substrate portion 11 in the intermediate substrate portion 13 of the flexible wiring substrate and the bending region continuous with the second substrate portion 12 The inner surface of is formed in a curved surface. Thus, the light emitted from the third light source device 29 can be easily deflected to the light directly directed to the main light emitting surface 401, and can be efficiently extracted from the main light emitting surface 401.

  As shown in FIG. 4B, in the light emitting device 400, the main light emitting surface 401 is constituted by the surface of the covering member 32. In particular, the main light emitting surface 401 of the present embodiment is formed to be convex toward the front, and light can be extracted from the main light emitting surface 401 more efficiently. Further, as shown in FIG. 4A, the side surface of the covering member 32 is also formed in a convex shape in the lateral direction. The shape of the covering member 32 is adjusted by adjusting the amount of the covering member 32 and pressing the first substrate portion 11 and / or the second substrate portion 12 when solidifying the covering member 32. It can be formed. In addition, although the main light emitting surface 401 protrudes forward from the tip (front surface) of the flexible wiring substrate 10, like the main light emitting surface in the light emitting device of the first to third embodiments described above, the flexible wiring By forming it inside the tip of the substrate, for example, the light emitting device can be easily brought close to the light incident surface (side surface) of the light guide plate of the backlight device, and the light coupling efficiency to the light guide plate can be easily improved. Furthermore, the end of the light guide plate may be located inside the tip of the flexible wiring board 10, in other words, the flexible wiring board may cover the end of the upper surface and / or the lower surface of the light guide plate. it can.

  In addition, the light-emitting device 400 can be bent and used because the covering member 32 has flexibility, and it is useful, for example, for a backlight device for a curved display.

  As mentioned above, although Embodiment 1-4 showed the example of the light-emitting device by which a light source device is mounted on the 1st board | substrate part 11 of a flexible wiring board at least, not only these but a light source device It may be mounted on the inner surface of at least one of the substrate unit 11, the second substrate unit 12, and the intermediate substrate unit 13, and may be mounted only on the inner surface of the intermediate substrate unit 13, for example.

  Hereinafter, each component of the light emitting device of the present invention will be described.

(Flexible wiring board 10, 17)
The flexible wiring substrate preferably includes at least a base and a wiring held on the base, and preferably further includes a protective film such as a coverlay or a solder resist. The flexible wiring substrate is not limited to a single layer substrate, but may be a laminated substrate. The thickness (total thickness) of the flexible wiring board is, for example, 0.05 mm or more and 2 mm or less, preferably 0.05 mm or more and 1 mm or less, and more preferably 0.05 mm or more and 0.5 mm or less. The size of the planar view before bending the flexible wiring substrate is not particularly limited, but may be, for example, about 3 mm to 10 mm in length and about 50 mm to 200 mm in width.

(Substrate 14)
As the substrate, a film of polyimide, polyethylene terephthalate, polyethylene naphthalate, liquid crystal polymer, cycloolefin polymer or the like can be used.

(Wiring 15)
The wiring is a conductor responsible for supplying power from the external power source to the light source device. The wiring may be formed on at least the upper surface of the substrate as a foil or a film, and may also be formed on the inside and / or the lower surface of the substrate. Further, the wiring preferably includes a land (die pad) portion to which the light source device is bonded, an external connection terminal portion, and a lead-out wiring portion connecting these. The external connection terminal portion is preferably provided at an end portion of the flexible wiring board (for example, an extending portion at the right end in each of the figures (a) and (c)) from the viewpoint of easy connection. It may be provided on the lower surface (the outer surface after bending) of the flexible wiring substrate, in particular, the lower surface of the first substrate portion. The wiring can be formed of copper, nickel, palladium, rhodium, tungsten, chromium, titanium, aluminum, silver, gold, or an alloy of these. It may be a single layer or multiple layers of these metals or alloys. In particular, copper or a copper alloy is preferable in terms of heat dissipation. In addition, a plating or light reflecting film of silver, aluminum, rhodium, platinum, gold or an alloy thereof may be provided on the surface layer, and silver having excellent light reflectivity is preferable among them.

(Light reflective member 16)
The light reflective member may be a member in which a white pigment is blended in a matrix of a polymer compound such as a resin. As a base material of a light reflective member, the same material as the below-mentioned covering member besides the same material as the above-mentioned base, etc. are mentioned. As white pigments, titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, zirconium oxide Etc. The light reflective member may be a protective film such as the above-described cover lay or solder resist. Besides, the light reflective member may be a metal film as long as short circuit such as wiring can be avoided through the insulating film. Such metal films include films of silver, aluminum, rhodium, platinum, or alloys thereof.

(Light source device 20, 22, 23, 25, 26, 27, 28, 29)
The light source device can use an LED chip or various LED packages. The LED package is a package type LED (especially surface mount type: SMD) in which an LED chip is sealed in a recess of a resin or ceramic package, and a substrate type LED (chip) in which the LED chip is mounted and sealed on a wiring substrate. On board: COB), a chip size package (CSP) in which a bump electrode and a phosphor layer are bonded to an LED chip. The resin package is made of particles of the same substance as the filler 35 described later (including fibrous form) in a matrix material such as polyamide resin, polycyclohexane terephthalate resin, epoxy resin, silicone resin, or modified resin or hybrid resin thereof. Can be formed. The thickness of the LED chip is preferably 0.05 mm or more and 1 mm or less, and more preferably 0.1 mm or more and 0.3 mm or less. The thickness of the LED package is preferably 0.2 mm or more and 1 mm or less, and more preferably 0.3 mm or more and 0.8 mm or less. After being mounted on a flexible wiring substrate, the LED chips may be individually sealed with a sealing member (which may contain a phosphor). In addition, when using two or more light source devices, the luminescent color of each light source device may be arrange | equalized substantially equally, and may be made to differ. For example, three types of light source devices that emit red, green, and blue light may be used. Further, the emission colors of the first light source device and the second light source device may be made different from each other.

LED chips, in particular, elements of the phosphor efficiently excitable nitride semiconductor _{(In x Al y Ga 1-} x-y N, 0 ≦ x, 0 ≦ y, x + y ≦ 1) are preferred. Besides, the LED chip may be a device of gallium arsenide based or gallium phosphide based semiconductor. When an LED chip is used as a light source device, the LED chip may be connected to the flexible wiring board by a wire, but the flip chip (face-down) mounting using a conductive adhesive may cause disconnection. Is preferred in that it is easy to suppress or avoid. For this reason, the LED chip is preferably an element having a light transmitting substrate and having positive and negative electrodes on the same side. The light transmitting substrate may, for example, be sapphire or gallium nitride. The substrate of the LED chip may be removed. The form and mounting form of the electrodes of the LED chip in the LED package are not particularly limited.

(Cover members 30, 32)
The covering member is electrically insulating and may be a flowable member before solidification. Specific base materials of the covering member include silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, TPX resin, polynorbornene resin, modified resin thereof, hybrid resin containing one or more of these resins, etc. Can be mentioned. In addition, various glasses may be used. Among them, silicone resins and modified resins thereof are preferable because they are excellent in heat resistance and light resistance, and are relatively easy to obtain flexibility. The covering member may contain a filler and / or a phosphor in these base materials.

(Filler 35)
The filler is silica, titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum sulfate, aluminum oxide, oxidized Zirconium, wollastonite, mica, potassium titanate, aluminum borate, silicon carbide, antimony oxide, zinc stannate, zinc borate, iron oxide, chromium oxide, manganese oxide, carbon black, aluminum nitride, silicon nitride, various glasses And the like particles (including fibrous) can be used.

(Phosphor 37)
The phosphor absorbs at least a part of the primary light emitted from the light source device or the light source in the light source device, and emits secondary light of a wavelength different from that of the primary light. The phosphor may be of one type or a combination of two or more types. Specific examples of the phosphor include yttrium aluminum garnet activated with cerium, nitrogen-containing calcium aluminosilicate activated with europium and / or chromium, sialon activated with europium, silicate activated with europium, manganese Preferred is activated potassium fluorosilicate or the like.

  The light-emitting device according to the present invention is a backlight source of a liquid crystal display, various lighting devices, a large display, various display devices such as advertisement or destination guidance, and images in digital video cameras, facsimiles, copiers, scanners, etc. It can be used for a reading device, a projector device, etc.

DESCRIPTION OF SYMBOLS 10, 17 ... Flexible wiring board (11 ... 1st board part, 12 ... 2nd board part, 13 ... Intermediate board part, 14 ... Base | substrate, 15 ... Wiring, 16 ... Light reflective member, 18 ... Side wall part)
20, 22, 23, 25, 26, 27, 28, 29 Light source device (20, 23, 25, 27 first light source device 22, 26, 28 second light source device 29, third light source device)
30, 32 ... Coating member (35 ... filler, 37 ... phosphor)
100, 200, 300, 400 ... light emitting devices (101, 201, 301, 401 ... main light emitting surface)

Claims (6)

A first substrate portion, a second substrate portion facing the first substrate portion, and an intermediate substrate portion between the first substrate portion and the second substrate portion, and the first substrate portion is bent; a flexible wiring board elongate shape in the transverse direction each part and the second substrate portion and the intermediate substrate portion,
A plurality of first light source devices mounted on the inner surface of the first substrate portion via a conductive first adhesive along the longitudinal direction of the flexible wiring substrate;
And a plurality of second light source devices mounted on the inner surface of the second substrate portion via a conductive second adhesive along the longitudinal direction of the flexible wiring substrate. ,
The intermediate substrate portion has a light reflecting member other than the wiring, and is provided on the side opposite to the main light emitting surface of the light emitting device.
An electrically insulating covering member is provided for bonding the inner surface of the first substrate portion, the inner surface of the second substrate portion, and the first light source device and the second light source device,
The first light source device and the second light source device are side-emitting LED packages,
When the light emitting device is viewed from the main light emitting surface side, the first light source device and the second light source device are disposed so as not to face each other in the vertical direction,
The distance between the inner surface of the first substrate unit and the inner surface of the second substrate unit is twice or less the thickness of the first light source device,
The first adhesive is disposed on a side surface of the first light source device,
The second adhesive is disposed on a side surface of the second light source device,
The first adhesive and the second adhesive do not interfere with each other ,
When the said light-emitting device is seen from the said main light emission surface side, the said LED package is a light-emitting device whose width of the main surface by the side of mounting is larger than the width of the main surface by the side opposite to the said mounting side . The light emitting device according to claim 1, wherein the first substrate unit and / or the second substrate unit includes a light reflective member other than the wiring. The light emitting device according to claim 1 , wherein the covering member is translucent. The light emitting device according to any one of claims 1 to 3 , wherein the covering member contains a filler. The light emitting device according to any one of claims 1 to 4 , wherein the covering member is flexible. The light emitting device according to any one of claims 1 to 5, further comprising a third light source device mounted on an inner surface of the intermediate substrate portion.

Images