JP2010146931A - Linear light source device and planar illumination device - Google Patents

Abstract

The present invention provides a linear light source device that includes a plurality of LED chips and that can easily cope with an increase in length, and a sidelight type planar illumination device to which the linear light source device is applied.
[Solution]
The linear light source device 10 includes three LED packages 11 and an insulating substrate 27 on which each of the LED packages 11 is mounted along one direction. The LED package 11 includes four LED chips 12 arranged in one direction and a lead frame 14 on which the LED chips 12 are mounted. The lead frame 14 has a mounting portion 16 for mounting the LED chip 12 and a pair of electrode terminal portions 21 formed separately at both ends outside the mounting portion 16. The mounting portion 16 is configured to be located behind the pair of electrode terminal portions 21. On the other hand, three through holes 28 are formed in the insulating substrate 27, and the mounting portions 16 of the LED packages 11 are arranged in the three through holes 28, respectively.
[Selection] Figure 1

Description

  The present invention relates to a linear light source device configured by arranging a plurality of bare chip-shaped light emitting elements in one direction, and a sidelight type planar illumination device using the linear light source device, and more particularly to relatively display. The present invention relates to a linear light source device suitable for a backlight for a liquid crystal display panel having a large area, and a planar illumination device.

  A so-called sidelight type planar illumination device in which a light source is arranged on the side surface of a light guide plate as illumination means for a liquid crystal display panel is advantageous for thinning. Widely adopted in the center. As a light source disposed on the side surface of the light guide plate, a small LED (Light Emitting Diode) having excellent environmental compatibility is frequently used.

  Recently, as the performance of light guide plates and LEDs has improved, the field of application of sidelight type planar lighting devices has expanded. For example, the display area used in car navigation systems, notebook computers, desktop computers, etc. It is also being applied to large liquid crystal display panels.

  In order to apply a sidelight type planar illumination device using LEDs as a light source to a large liquid crystal display panel, it is necessary to arrange more LEDs on the light incident surface of the light guide plate in response to the expansion of the illumination area. . As a means for increasing the number of LEDs, a plurality of LED chips are arranged in one direction (straight) instead of a point light source configured by arranging one LED chip (LED bare chip) in one package. It has been studied to use a long linear light source arranged in an array. (For example, see Patent Document 1)

  The light emitting module (linear light source device) disclosed in Patent Document 1 has a plurality of LED chips mounted directly on a lead frame excellent in heat dissipation and light reflectivity, and excellent insulation on the back side of the lead frame. A heat-dissipating metal substrate is disposed through the thermally conductive resin. Thereby, the light emitting module excellent in heat dissipation is realized.

  In addition, by bending the lead frame in a concave shape along one direction (LED chip arrangement direction), a pair of side wall surfaces serving as a reflection plate for light emitted in a direction orthogonal to the one direction is formed. Thereby, the light emitted toward the pair of side wall surfaces from the LED chip can be reflected toward the front (illuminated body side), and a light emitting module excellent in light emission efficiency is realized.

JP 2007-165843 A

  By configuring the light emitting module as described above, a linear light source excellent in heat dissipation and light emission efficiency can be realized.

  However, when the light emitting module disclosed in Patent Document 1 is further lengthened to cope with a larger liquid crystal display panel, it is difficult to ensure mechanical strength and the assembling workability is deteriorated. There is a problem of fear. This is because, from the viewpoint of workability of the lead frame, there is a limit to increasing the thickness of the lead frame forming the casing of the light emitting module alone, and it becomes difficult to ensure rigidity proportional to the lengthening.

  In the light emitting module, the lead frame is divided into two along one direction, and one of them functions as an anode electrode and the other functions as a ground electrode. For this reason, in order to arrange the divided lead frame on the heat radiating metal substrate made of the same block, it is necessary to ensure insulation between the lead frame and the heat radiating metal substrate. For this reason, there is a problem that it is necessary to fix the lead frame to the metal substrate for heat dissipation through a heat conductive resin having excellent insulating properties.

  In addition, the light emitting module has a problem that improvement in optical performance is always required.

  Therefore, the present invention has been made in view of the above-described problems, and is a linear light source device that excels in assembly workability, is easily adaptable to lengthening, and has excellent optical performance, and the linear light source device. It is an object of the present invention to provide a sidelight type planar illumination device that can be easily applied to expansion of an illumination area by being applied as a planar light source.

  In order to solve the above problems, the linear light source device according to the present invention is characterized in that a plurality of light emitting element packages each having a plurality of light emitting element chips mounted on a lead frame along one direction, and the light emitting element package. And an insulating substrate on which a wiring pattern for supplying a driving signal to each light emitting device package is formed, and the lead frame includes each of the light emitting device chips. A strip-shaped mounting part to be mounted, and a pair of electrode terminal parts arranged separately from the mounting part on both outer sides in one direction of the mounting part, each of the electrode terminal parts, A connection terminal disposed near the mounting portion and electrically connected to an electrode pad of the wiring pattern, and an inclination configured to be disposed on the outer side in the one direction of the connection terminal and to spread toward the front outer side. Preparative includes, on the insulating substrate, in response to each of the light emitting device package, in that a plurality of positioning recesses for accommodating a portion of the light emitting device packages are formed, respectively.

  In this case, the mounting portion of the lead frame is configured to protrude rearward from the pair of electrode terminals, and the positioning recess of the insulating substrate is configured to accommodate the mounting portion of the lead frame. It may be formed. Further, the pair of electrode terminal portions of the lead frame each have a folded piece extending from the front outer front end of the inclined wall toward the insulating substrate side, and the positioning recess of the insulating substrate is the folded piece. It may be formed so that each of the tip portions thereof is accommodated.

  According to this invention, a long linear light source device is configured by arranging a plurality of light emitting element packages in which a plurality of light emitting element chips are arranged in one direction in the same direction. For this reason, the length of each light emitting element package can be suppressed (adjusted) to a length that can ensure a desired mechanical strength. Further, by mounting a plurality of light emitting element packages on one insulating substrate as a circuit board, the plurality of light emitting element packages are integrated. Thereby, the mechanical strength as the whole linear light source device is securable. Further, since the chromaticity can be adjusted for each light emitting element package, the chromaticity of the entire linear light source device can be easily adjusted.

  In addition, a pair of electrode terminal portions (connection terminals) electrically connected to the wiring pattern formed on the insulating substrate is provided separately (independently) from the mounting portion on which the light emitting element chip is mounted. That is, the mounting portion is configured not to function as an electrode. As a result, the heat sink can be brought into direct contact with the back surface of the lead frame mounting portion (the surface opposite to the surface on which the light emitting element chip is mounted). Alternatively, it is possible to fix the heat sink to the back surface of the mounting portion using a conductive resin having excellent thermal conductivity. As a result, the cooling efficiency by the heat sink is improved. By improving the cooling efficiency, a large driving current can be passed through the light emitting element chip, and the amount of light emitted from the linear light source device is increased.

  In addition, the light emitting device chips are configured to spread outward at both ends in the longitudinal direction (corresponding to one direction) of the mounting portion on which each light emitting device chip is mounted and toward the front (side toward the light emitting surface of the light emitting device chip). A pair of inclined walls is provided. Thereby, the light radiate | emitted along one direction from each light emitting element chip | tip can be reflected ahead, and luminous efficiency improves.

  Further, the lead frame connection terminals to be electrically connected to the electrode pads of the insulating substrate are arranged on the inner side (closer to the mounting portion) than the inclined wall. For this reason, even if the dimensions and positions of the electrode pads formed on the insulating substrate vary, there is no possibility that the electrode pads come into contact with the connection terminals of the adjacent light emitting element packages. That is, the dimensional accuracy and position accuracy of the electrode pad can be relaxed. Further, the interval between adjacent light emitting device packages can be made as narrow as possible, and uniform illumination light with a small dark portion can be obtained.

  Further, since the positioning recess for arranging a part of the light emitting element package is formed on the insulating substrate, the alignment of the individual light emitting element packages is facilitated. In addition, the positional deviation at the time of electrical bonding of the light emitting element package to the insulating substrate (at the time of solder bonding) is suppressed. Thereby, the dispersion | variation in the optical characteristic between individual | individuals is suppressed, and the linear light source device excellent in assembly workability | operativity is realizable.

  Another feature of the linear light source device according to the present invention is that the positioning recess is formed as a through hole penetrating from the surface on the side where the light emitting element package is disposed to the surface on the opposite side. The surface of the mounting part opposite to the surface on which the light emitting element chips are arranged is exposed to the outside.

  According to this invention, the back surface of the mounting portion on which the plurality of light emitting element chips of the lead frame are mounted is exposed to the outside. As a result, the heat sink can be brought into contact with the back surface of the mounting portion from the outside, and the heat transmitted from the light emitting element chip to the heat sink can be efficiently released to the outside.

  In addition, the surface illumination device according to the present invention is characterized by any one of the linear light source devices described above, a light incident surface that receives light emitted from the linear light source device, and light incident from the light incident surface. And a light guide plate having an emission surface for emitting light.

  According to this invention, it is possible to realize a planar illumination device that can effectively exhibit the effects of the linear light source device described above and can easily cope with an increase in the size of the illumination area.

  Further, in this case, the lead frame extends substantially parallel to each other from a pair of long reflection wall portions extending forward from both end edges along the one direction of the mounting portion and the pair of long reflection wall portions. A pair of protrusions, wherein the pair of protrusions sandwich the vicinity of the light incident surface of the light guide plate. According to this invention, the linear light source device and the light guide plate can be integrated via the lead frame.

[First Embodiment]
<Linear light source device>
Hereinafter, a linear light source device 10 according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view schematically showing the overall configuration of the linear light source device 10. FIG. 2 is a partially enlarged cross-sectional view along the longitudinal direction of the linear light source device 10, and FIG. 3 is a cross-sectional view along the short direction of the linear light source device 10.

  As shown in FIG. 1, the linear light source device 10 includes a plurality of (three in this embodiment) LED packages arranged in one direction (straight) (hereinafter, this arrangement direction is referred to as “one direction”). (Light emitting element package) 11 and a long insulating substrate 27 on which each of the LED packages 11 is mounted.

  As shown in FIG. 2, the LED package 11 includes a plurality of (four in this embodiment) LED chips (light emitting element chips) 12 arranged in one direction, and a lead frame 14 on which each of the LED chips 12 is mounted. And a resin sealing body 25 that integrally covers the plurality of LED chips 12 and the lead frame 14 are linearly configured.

  In the present embodiment, the LED chip 12 is a blue LED chip (bare chip) that has a pair of electrodes (not shown) on the light emitting surface 12a that is the surface thereof and emits blue light (410 nm to 480 nm). The LED chip 12 is mounted on the lead frame 14 with the back surface (the surface opposite to the light emitting surface 12a) as an adhesive surface. Further, wire bonding is performed on the pair of electrodes on the light emitting surface 12 a, and the four LED chips 12 are connected in series by the bonding wires 26.

  The lead frame 14 is formed of a material (in this embodiment, a silver-plated copper plate, hereinafter referred to as a silver-plated copper plate) that is excellent in thermal conductivity, workability, and light reflectivity and that can be wire-bonded. The lead frame 14 includes a main body portion 15 and a pair of electrode terminal portions 21 as shown in a development view (including four LED chips 12 indicated by a two-dot chain line) in FIG. In addition, the broken line in FIG. 4 has shown the bending position at the time of bending the lead frame 14. FIG.

  The main body portion 15 includes a strip-shaped mounting portion 16 on which the four LED chips 12 are mounted, four rectangular hanging wall portions 17 connected to the four outer peripheral edges of the mounting portion 16, and four hanging walls, respectively. The rectangular portion 17 is connected to the outer edge side of a pair of vertical wall portions (long vertical wall portions) 17a parallel to one direction (longitudinal direction), and the length in one direction is longer than the long vertical wall portion 17a. And a pair of long reflecting wall portions 18 having a shape.

  The mounting part 16 is electrically disconnected from the electrodes of the four LED chips 12 to be mounted. That is, the main body portion 15 including the mounting portion 16 is configured not to have a function as an electrode.

  As shown in FIGS. 2 and 3, the four vertical wall portions 17 are bent vertically from the outer peripheral edge of the mounting portion 16 toward the front (the side on which the light emitting surface 12 a of the LED chip 12 faces). As a result, the four LED chips 12 are surrounded by the four vertical wall portions 17. The height of the four vertical wall portions 17 (the length in the vertical direction in FIG. 3) is set to a value obtained by adding the thickness of a solder connection layer including an electrode pad 29 described later to the thickness of the insulating substrate 27. .

  As shown in FIG. 3, the pair of long reflecting wall portions 18 are bent so as to spread at a predetermined angle toward the front outer side. Thereby, the light radiate | emitted toward the up-down direction (short direction orthogonal to one direction) of illustration from the LED chip 12 can be reflected ahead.

  On the other hand, as shown in FIG. 4, the pair of electrode terminal portions 21 are disposed on the outer sides of both ends in one direction of the main body portion 15 so as to be separated from the main body portion 15. As shown in FIG. 2, each electrode terminal portion 21 is disposed at substantially the same height as the upper end edge of the vertical wall portion 17, and is connected to a connection terminal 22 that is substantially parallel to the mounting portion 16 and has a rectangular planar shape. The terminal 22 includes a rectangular flat inclined wall 23 that is connected to the outer edge of the terminal 22 in one direction and is inclined to spread outward at a predetermined angle. That is, the pair of inclined walls 23 are configured to spread toward the front outside. For the pair of connection terminals 22, one electrode of each adjacent LED chip 12 (an electrode not connected to the adjacent LED chip 12) and a bonding wire 26 (not shown in FIGS. 1 and 3) are used. Are electrically connected.

  Next, the resin sealing body 25 is formed using a translucent material (silicone resin in the present embodiment), and the translucent material receives blue light emitted from the LED chip 12 and receives a yellow component. The yellow phosphor that emits the light is dispersed. That is, the resin sealing body 25 is formed so that predetermined white light can be obtained by mixing blue light emitted from the LED chip 12 and yellow light emitted from the yellow phosphor. In this embodiment, the resin sealing body 25 is integrally formed with the lead frame 14 in an area surrounded by the lead frame 14 (the main body portion 15 and the pair of electrode terminal portions 21) by an insert molding method. In the illustrated example, the resin sealing body 25 is also present outside the pair of long reflecting wall portions 18 and the pair of inclined walls 23. However, the light-transmitting material is not necessarily present in these portions. Good.

  Next, the insulating substrate 27 on which the plurality of LED packages 11 are mounted will be described. The insulating substrate 27 is, for example, a substrate (in this embodiment, a glass epoxy substrate) having high rigidity and excellent insulating properties and workability, and is formed in a long rectangular plate shape as a whole. As shown in FIG. 1, the insulating substrate 27 includes a plurality of (three in the embodiment, the number of LED packages 11) through-holes (positioning recesses) 28 penetrating in the thickness direction, and a plurality of (LED packages). A pair of electrode pads 29 corresponding to the number of 11).

  The three through holes 28 are formed at a predetermined pitch along the longitudinal direction (corresponding to one direction) of the insulating substrate 27. The predetermined pitch is set slightly longer than the length of the LED package 11 in the longitudinal direction. In addition, the opening shape of each through hole 28 is the same as the planar view shape of the mounting portion 16 of the lead frame 14 or is slightly larger than that.

  By forming the through hole 28 in this way, as shown in FIGS. 2 and 3, a rectangular parallelepiped region (virtual plane including the connection terminals 22) surrounded by the mounting portion 16 and the four hanging wall portions 17 of the LED package 11. The convex portion protruding rearward) is inserted or inserted (accommodated) into the through hole 28. Accordingly, the three LED packages 11 are positioned with respect to the insulating substrate 27, respectively. At this time, the back surface of the mounting portion 16 (surface opposite to the surface on which the LED chip 12 is mounted) and the back surface of the insulating substrate 27 (surface opposite to the surface on which the LED package 11 is mounted) are substantially flush. Become. In addition, the three LED packages 11 are arranged in a straight line with a slight gap W1 between the adjacent LED packages 11 so as not to be short-circuited.

  The pair of electrode pads 29 is formed in a rectangular shape in plan view at a position facing the connection terminal 22 of the lead frame 14 in a state where the three LED packages 11 are mounted on the insulating substrate 27. In other words, the pair of electrode pads 29 are respectively formed on both outer sides in the longitudinal direction of the corresponding through hole 28. The connection terminal 22 and the electrode pad 29 are solder-connected by, for example, a reflow process, thereby being electrically connected to each other. The electrode pad 29 is connected to a wiring pattern (not shown) formed on the insulating substrate 27, and a drive signal (electric signal) supplied from the outside is fed to each of the three LED packages 11. It has become so.

  Next, the operation of the linear light source device 10 according to the first embodiment will be described. Drive signals from a control circuit (not shown) installed outside are applied to the electrode terminal portions 21 (connection terminals 22) of the three LED packages 11 via the wiring patterns on the insulating substrate 27 and the electrode pads 29, respectively. Applied. The drive signal applied to the electrode terminal portion 21 is fed to each LED chip 12 via the bonding wire 26. Each LED chip 12 emits blue light based on a drive signal supplied with power. A part of the blue light is converted into yellow light by the yellow phosphor mixed in the resin sealing body 25, and white light is generated by mixing the blue light and the yellow light. And when all the LED chips 12 arranged in the same direction emit light, linear white light is obtained as a whole.

  The generated linear white light is emitted forward, and enters, for example, a light incident surface (see FIG. 5 described later) of a light guide plate constituting a sidelight type planar illumination device (backlight). The linear white light incident on the light guide plate is converted into planar light by an optical path changing means such as a dot pattern formed on the back surface (reflective surface) of the light guide plate, and is illuminated (for example, a liquid crystal display panel) Illuminate.

  Next, the operation and effect of the linear light source device 10 having the above configuration will be described. The linear light source device 10 includes a plurality of linear LED packages 11 in which a plurality of LED chips 12 are arranged in one direction, and an insulating substrate 27 on which the plurality of LED packages 11 are mounted in one direction. Has been. That is, even when the number of LED chips 12 arranged in one direction is relatively large, all the LED chips 12 can be subdivided according to the number of LED packages 11. For this reason, the length of each LED package 11 can be suppressed to a length that can ensure mechanical strength. Moreover, the mechanical strength as the whole linear light source device 10 is also securable by mounting and integrating the several LED package 11 in the insulated substrate 27. FIG.

  Further, since the chromaticity can be adjusted for each LED package 11, the chromaticity adjustment of the linear light source device 10 as a whole becomes easy. In particular, when configured as a pseudo white LED comprising a combination of a monochromatic light source (blue LED) and a phosphor (yellow phosphor) as described above, the effect is effectively exhibited.

  In addition, a pair of electrode terminal portions 21 (connection terminals 22) to be electrically connected to the wiring pattern formed on the insulating substrate 27 are provided independently of the mounting portion 16 of the lead frame 14 on which the LED chip 12 is mounted, The mounting unit 16 does not have a function as an electrode. For this reason, the heat sink can be brought into direct contact with the mounting portion 16 of the lead frame 14 (see FIG. 5 described later). Alternatively, it is possible to fix the heat sink to the mounting portion 16 using a resin that has conductivity and is excellent in thermal conductivity. As a result, the cooling efficiency by the heat sink is improved. In addition, a pair of inclined walls 23 configured to spread at a predetermined angle toward the front outer side are provided on both outer sides in the longitudinal direction of the mounting portion 16 on which each of the LED chips 12 is mounted. The light emitted from the LED chip 12 in the lateral direction (one direction) can be reflected forward. As a result, further improvement in luminous efficiency can be expected.

  In addition, since the connection terminal 22 of the lead frame 14 to be electrically connected to the electrode pad 29 of the insulating substrate 27 is disposed on the inner side (mounting part 16 side) than the inclined wall 23, the dimensional variation of the electrode pad 29 is reduced. Even if a positional deviation occurs, there is no risk of contact with the connection terminal 22 of the adjacent LED package 11. That is, the dimensional accuracy and position accuracy of the electrode pad 29 are relaxed. Moreover, the space | interval between adjacent LED packages 11 can be narrowed as much as possible, and uniform illumination light with a small dark part is obtained.

  Moreover, since the through-hole 28 as a positioning recessed part which arrange | positions a part of LED package 11 was formed in the insulating substrate 27, position alignment of each LED package 11 becomes easy. Moreover, the position shift of the LED package 11 in a reflow process can be suppressed. Thereby, the linear light source device 10 which is excellent in assembling workability and can obtain stable optical characteristics can be realized.

<Surface lighting device>
The linear light source device 10 having such an effect is suitable, for example, as a linear light source of a sidelight type planar illumination device having a relatively large illumination area. FIG. 5 shows a configuration example in the case where the linear light source device 10A is applied as the linear light source of the sidelight type planar illumination device.

  A planar illumination device 30 shown in FIG. 5 includes a linear light source device 10A according to the present embodiment, a light incident surface that receives light emitted by the linear light source device 10A, and light that enters from the light incident surface. A rectangular light guide plate 31 having a light exit surface and a rectangular parallelepiped shape disposed so as to be in direct contact with the mounting portion 16 of the lead frame 14 on the back portion (the side opposite to the light guide plate 31) of the linear light source device 10A. And a housing frame 37 having a U-shaped cross section for accommodating the linear light source device 10 </ b> A and the heat sink 36. In addition, a reflection sheet 32 is disposed on the reflection surface (lower surface in the drawing) side that scatters and reflects light incident on the light guide plate 31, and emits light from the light guide plate 31 toward the illuminated body (liquid crystal display panel). A diffusion sheet 33 and two prism sheets 34 and 35 are arranged on the surface (upper surface in the drawing) side.

  The linear light source device 10 </ b> A is different from the linear light source device 10 in that it includes a pair of protruding portions 19 that protrude forward from the tips of the pair of long reflecting wall portions 18 of the lead frame 14 substantially in parallel to each other. The pair of protrusions 19 sandwich the vicinity of the light incident surface of the light guide plate 31 including the reflection sheet 32, the diffusion sheet 33, and the two prism sheets 34 and 35. Thereby, the linear light source device 10 </ b> A can be integrated with the light guide plate 31. In addition, light leaking from the vicinity of the light incident surface of the light guide plate 31 can be suppressed. Furthermore, it is possible to directly radiate heat to the housing of the liquid crystal module, for example, through the protruding portion 19 exposed to the outside.

[Second Embodiment]
<Linear light source device>
Hereinafter, a linear light source device 50 according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 6 is an exploded perspective view schematically showing the overall configuration of the linear light source device 50. FIG. 7 is a partially enlarged cross-sectional view along the longitudinal direction of the linear light source device 50, and FIG. 8 is a cross-sectional view along the short direction of the linear light source device 50. In addition, the same code | symbol is attached | subjected to the member which is common in 1st Embodiment, and description is abbreviate | omitted suitably.

  As shown in FIG. 6, the linear light source device 50 includes a plurality (three in the present embodiment) of LED packages (light emitting element packages) 51 arranged in one direction (straight), and each of the LED packages 51. And a long insulating substrate 67 on which is mounted.

  As shown in FIG. 7, the LED package 51 includes a plurality (four in this embodiment) of LED chips (light emitting element chips) 12 arranged in one direction, and a lead frame 54 on which the plurality of LED chips 12 are mounted. And a resin sealing body 65 that integrally covers the plurality of LED chips 12 and the lead frame 54 are linearly configured.

  The LED chip 12 is mounted on the lead frame 54 so that the back surface side is an adhesive surface, wire bonding is performed on the light emitting surface 12 a, and four LED chips 12 are connected in series by bonding wires 66.

  The lead frame 54 is formed using a silver-plated copper plate, and as shown in a development view (including four LED chips 12 indicated by a two-dot chain line) in FIG. 9, a main body portion 55, a pair of electrode terminal portions 61, and , Is composed of. In addition, the broken line in FIG. 9 has shown the bending position at the time of bending the lead frame 54. FIG.

  The main body portion 55 is connected to the strip-shaped mounting portion 56 on which the four LED chips 12 are mounted and the outer edge side parallel to one direction (longitudinal direction) of the mounting portion 56, and has a length in one direction. And a pair of rectangular long reflection wall portions 58 that are longer than the length of the mounting portion 56.

  The mounting part 56 is electrically disconnected from the electrodes of the four LED chips 12 to be mounted. That is, the main body portion 55 of the lead frame 54 is configured not to have a function as an electrode.

  As shown in FIG. 8, the pair of long reflective wall portions 58 are bent so that one (upper side in the drawing) of the long reflective wall portion (upper long reflective wall portion) 58a spreads at a predetermined angle toward the front outer side. In contrast, the other long reflection wall portion (lower long reflection wall portion) 58b is bent vertically from the mounting portion 56 toward the front.

  On the other hand, as shown in FIG. 9, the pair of electrode terminal portions 61 are disposed on the outer sides in one direction of the main body portion 55 so as to be separated from the main body portion 55. As shown in FIG. 7, each electrode terminal portion 61 is positioned substantially on the same plane as the mounting portion 56, and has a connection terminal 62 formed in a rectangular planar shape, and an outer edge in one direction of the connection terminal 62. A rectangular flat inclined wall 63 that is connected and bent so as to spread at a predetermined angle toward the front outer side, and an elongated shape that extends continuously from substantially the center of the front outer edge of the inclined wall 63 toward the rear. And a strip-shaped folded piece 64.

  The pair of connection terminals 62 are electrically connected to one electrode of the adjacent LED chip 12 (an electrode not connected to the adjacent LED chip 12) and a bonding wire 66 (see FIG. 7). .

  The folded piece 64 is bent so as to intersect substantially perpendicular to a plane parallel to the mounting portion 56 (or connection terminal 62). The length of the folded piece 64 in the folded state is such that the tip of the folded piece 64 has a thickness of the solder connection layer including the electrode pads 29 described later in the thickness of the insulating substrate 67 rather than the virtual plane including the connection terminals 62. The value obtained by adding is set to a length located rearward.

  The resin sealing body 65 leads to a substantially rectangular parallelepiped region surrounded by the lead frame 54 (the main body portion 55 and the pair of electrode terminal portions 61) by an insert molding method using the same material as that described in the first embodiment. It is formed integrally with the frame 54.

  Next, the insulating substrate 67 on which the plurality of LED packages 51 are mounted will be described. The insulating substrate 67 is also a glass epoxy substrate in the present embodiment, and is formed in a long rectangular flat plate shape as a whole. As shown in FIG. 6, the insulating substrate 67 includes a plurality of (three sets corresponding to the number of LED packages 51) that penetrates in the thickness direction and a plurality ( A pair of electrode pads 69 corresponding to the number of LED packages 51 and a plurality of notches 70 corresponding to the number of LED packages 51 are formed.

  The three pairs of through holes 68 are formed at a predetermined pitch along the longitudinal direction (corresponding to one direction) of the insulating substrate 67. The predetermined pitch is set slightly longer than the length of the LED package 51 in the longitudinal direction. The distance between the two through holes 68 constituting the pair of through holes 68 is set to a length that matches the distance between the pair of folded pieces 64 of the lead frame 54. In addition, the opening shape of each through hole 68 is the same as the cross-sectional shape of the folded piece 64 or is slightly larger than that.

  By forming the pair of through holes 68 in this way, as shown in FIG. 7, the tip portions of the pair of folded pieces 64 (convex portions protruding rearward from the virtual plane including the connection terminals 62) are paired through. The hole 68 is inserted or inserted (accommodated). Thereby, the three LED packages 51 are each positioned with respect to the insulating substrate 67. At this time, the tips of the pair of folded pieces 64 and the back surface of the insulating substrate 67 are substantially flush. Further, the three LED packages 51 are arranged in a straight line with a slight gap W2 between the adjacent LED packages 51 so as not to be short-circuited.

  The pair of electrode pads 69 are formed at positions facing the connection terminals 62 of the lead frame 54 when the LED package 51 is mounted on the insulating substrate 67. That is, the pair of electrode pads 69 are formed on the inner side in the longitudinal direction than the corresponding pair of through holes 68. For example, the connection terminal 62 and the electrode pad 69 are solder-connected by a reflow process, and are thereby electrically connected to each other. The electrode pad 69 is connected to a wiring pattern (not shown) formed on the insulating substrate 67, and a drive signal supplied from the outside is supplied to each of the three LED packages 51. ing.

  As shown in FIG. 8, the cutout portion 70 is viewed in plan from the outer peripheral edge on the side where the lower long reflection wall portion 58b is arranged in a state where the LED package 51 is mounted on the insulating substrate 67. It is formed in a long rectangular shape. As shown in FIG. 7, the length of the cutout portion 70 in the longitudinal direction is set somewhat shorter than the length of the mounting portion 56 in the lead frame 54 in the longitudinal direction. On the other hand, the length in the short direction of the notch 70 is set somewhat shorter than the length in the short direction of the mounting portion 56 in the lead frame 54 as shown in FIG.

  By forming the cutout portion 70 in this manner, the mounting portion 56 of the lead frame 54 can be stably mounted on the insulating substrate 67 and the portion excluding the vicinity of the outer peripheral edge of the back surface of the mounting portion 56 is exposed to the outside. be able to. As a result, the heat sink can be brought into direct contact with the back surface of the mounting portion 56 (see FIG. 10 described later). In place of this, it is possible to fix the heat sink to the mounting portion 56 using a resin that has conductivity and is excellent in thermal conductivity. Note that the cutout portion 70 should be formed as necessary, and need not be provided depending on the specifications of the apparatus.

  The linear light source device 50 having the above-described configuration performs the same operation as that described for the linear light source device 10 according to the first embodiment, and can exhibit the same operations and effects.

<Surface lighting device>
The linear light source device 50 is suitable, for example, as a linear light source of a sidelight type planar illumination device having a relatively large illumination area. FIG. 10 shows a configuration example when the linear light source device 50A is applied as the linear light source of the sidelight type planar illumination device.

  A planar illumination device 80 shown in FIG. 10 includes a linear light source device 50A according to the present embodiment and a rectangular light guide plate 31 in which the linear light source device 50A is disposed along a light incident surface that is one end surface. A rectangular parallelepiped heat sink 86 disposed on the back of the linear light source device 50A (on the side opposite to the light guide plate 31) so as to be in direct contact with the mounting portion 56 of the lead frame 54, the linear light source device 50A, and the light guide plate 31 and a housing frame 87 for holding the heat sink 86. A reflection sheet 32 is disposed on the lower surface (reflection surface) side of the light guide plate 31, and a diffusion sheet 33 and two prism sheets 34 and 35 are disposed on the upper surface (emission surface) side of the light guide plate 31.

  In addition, the linear light source device 50A includes a pair of protrusions protruding substantially in parallel to the front from the ends of the pair of long reflection wall portions 58 (the upper long reflection wall portion 58a and the lower long reflection wall portion 58b) of the lead frame 54. 59 in that it is different from the linear light source device 50. The pair of protrusions 59 sandwich the vicinity of the light incident surface of the light guide plate 31. Thereby, the linear light source device 50 </ b> A can be integrated with the light guide plate 31. In addition, light leaking from the vicinity of the light incident surface of the light guide plate 31 can be suppressed. Furthermore, it is easy to radiate heat directly to, for example, the housing flat portion of the liquid crystal module through the lower long reflecting wall portion 58b exposed to the outside in the same plane and the lower protruding portion 59.

[Other Embodiments]
The preferred embodiments of the present invention have been described above. However, the embodiments are not limited to the above, and various changes and combinations can be made based on the gist of the present invention.

  For example, in any of the above embodiments, the positioning recess for positioning the LED packages 11 and 51 has been described as the through holes 28 and 68 penetrating in the thickness direction of the insulating substrates 27 and 67. However, the present invention is not limited to this. For example, a bottomed non-through hole may be used instead of the through hole.

  In addition, the inclined walls 23 and 63 and the long reflecting wall portions 18 and 58 have been described as planar, but the present invention is not limited to this, and may be curved, for example.

  The plurality of LED chips 12 are not limited to blue LED chips, and may be composed of, for example, three primary color (RGB) LED chips. Further, the phosphor dispersed in the resin sealing bodies 25 and 65 in the case of using a blue LED chip is not limited to the yellow phosphor. For example, the phosphor that emits green light and the phosphor that emits red light. It is good also as the fluorescent substance which consists of. Further, for example, a semiconductor laser chip may be applied instead of the LED chip.

  Moreover, although the case where the several LED chip 12 was connected in series (series drive) was demonstrated, it is not limited to this, You may connect in parallel (parallel drive).

  Further, the linear light source devices 10 and 50 according to the present invention are suitable for the linear light source of the sidelight type planar illumination device, but are not limited to this, and can be applied to other uses. Is.

It is a disassembled perspective view which shows the whole structure of the linear light source device which concerns on the 1st Embodiment of this invention. It is a partial expanded sectional view which follows the 2-2 line of the linear light source device. It is sectional drawing which follows the 3-3 line of the linear light source device. It is a plane expanded view for demonstrating the lead frame of the same linear light source device. It is a longitudinal cross-sectional view which shows an example of the planar illuminating device comprised by attaching the same linear light source device to the light-guide plate. It is a disassembled perspective view which shows the whole structure of the linear light source device which concerns on the 2nd Embodiment of this invention. It is a partial expanded sectional view which follows the 7-7 line | wire of the same linear light source device. It is sectional drawing which follows the 8-8 line | wire of the same linear light source device. It is a plane expanded view for demonstrating the lead frame of the same linear light source device. It is a longitudinal cross-sectional view which shows an example of the planar illuminating device comprised by attaching the same linear light source device to the light-guide plate.

Explanation of symbols

10, 10A, 50, 50A Linear light source device 11, 51 LED package 12 LED chip 12a Light emitting surface 14, 54 Lead frame 15, 55 Body portion 16, 56 Mounting portion 17 Hanging wall portion 17a Long hanging wall portion 18, 58 Long Reflective wall portion 58a Upper long reflective wall portion 58b Lower long reflective wall portion 19, 59 Protruding portion 21, 61 Electrode terminal portion 22, 62 Connection terminal 23, 63 Inclined wall 25, 65 Resin sealing body 26, 66 Bonding wire 27 , 67 Insulating substrate 28, 68 Through hole (positioning recess)
29, 69 Electrode pads 30, 80 Planar illumination device 31 Light guide plate 32 Reflective sheet 33 Diffusion sheet 34, 35 A pair of prism sheets 36, 86 Heat sink 37, 87 Housing frame 64 Folding piece 70 Notch W1, W2 Gap

Claims (6)

A plurality of light emitting device packages formed by mounting a plurality of light emitting device chips along one direction on a lead frame;
Each of the light emitting device packages is mounted along the same direction as the one direction, and an insulating substrate on which a wiring pattern for supplying a driving signal to each light emitting device package is formed.
The lead frame has a strip-shaped mounting portion for mounting each of the light emitting element chips, and a pair of electrode terminal portions arranged separately from the mounting portion at both ends outside the one direction of the mounting portion, Have
Each of the electrode terminal portions is disposed near the mounting portion and is electrically connected to the electrode pad of the wiring pattern, and is disposed on the outer side in the one direction of the connection terminal and spreads toward the front outer side. The insulating substrate is formed with a plurality of positioning recesses that respectively accommodate a part of the light emitting device package corresponding to each of the light emitting device packages. Light source device. The linear light source device according to claim 1,
The mounting portion of the lead frame is configured to protrude rearward from the pair of electrode terminals,
The linear light source device, wherein the positioning recess of the insulating substrate is formed so as to accommodate the mounting portion of the lead frame. The linear light source device according to claim 2,
The positioning recess is formed as a through hole penetrating from the surface on the side where the light emitting element package is disposed to the surface on the opposite side, so that the surface of the mounting portion opposite to the surface on which the light emitting element chip is mounted. A linear light source device whose surface is exposed to the outside. The linear light source device according to claim 1,
The pair of electrode terminal portions of the lead frame each have a folded piece extending from the front outer front end of the inclined wall toward the insulating substrate side,
The linear light source device, wherein the positioning concave portion of the insulating substrate is formed so that a tip portion of the folded piece is accommodated. The linear light source device according to any one of claims 1 to 4,
A planar illumination device comprising: a light incident surface that receives light emitted from the linear light source device; and a light guide plate that includes an output surface that emits light incident from the light incident surface. The planar illumination device according to claim 5,
The lead frame includes a pair of long reflecting wall portions extending forward from both end edges along the one direction of the mounting portion, and a pair of protruding portions extending substantially parallel to each other from the tips of the pair of long reflecting wall portions. Have
The planar illumination device is configured such that the pair of protrusions sandwich the vicinity of the light incident surface of the light guide plate.

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