JP2019016629A - LED module - Google Patents

Abstract

To provide an LED module which is used for constituting a direct-type backlight and achieves both high luminance as a light source and lighting inspection easiness at the time of product shipment or the like.SOLUTION: Disclosed is an LED module 10 including: a substrate 1 for an LED element in which a metal wiring part 13 is formed on the surface of a support substrate 11; a plurality of LED elements 2 mounted on the metal wiring part 13; and a reflective material 15 laminated on the substrate 1 for the LED element while covering a region excluding an LED element mounting region. The reflective material 15 is made of resin sheet having flexibility. An opening is formed at a position corresponding to the LED element mounting region. A part of resin sheet is erected following to bending toward the top part of the LED element 2, thereby a side wall surrounding LED element 151 is formed in a portion in parallel with or roughly in parallel with a conduction direction between a pair of conductive plates 131, 132 out of the peripheral edge of the opening.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an LED module.

  In recent years, various LED display devices using an LED backlight as a light source, such as an in-vehicle display device, are rapidly spreading.

  In these display devices, in order to construct a backlight using an LED element as a light source, a circuit board for an LED element in which a metal wiring portion is formed on a support substrate (referred to as “LED element use in this specification”). Substrate ") is used. A laminate in which LED elements are mounted on such a substrate (in this specification, a laminate having such a configuration is referred to as an “LED module”) constitutes backlights of various LED display devices. Widely used as a light source module.

  The LED backlight includes an edge light type backlight in which LED elements are arranged on the side of the display surface, and a direct-type backlight that constitutes a surface light source by arranging LED elements as light sources on the back side of the display surface; It is divided roughly into. Among these, in particular, in the direct type LED backlight, in order to use the light emitted from the LED element more efficiently, the reflection for reflecting the light leaking to the back side of the LED backlight to the display screen side. The material is arranged around the LED element mounting region (see Patent Document 1).

  Here, in order to use the light emitted from the LED element more efficiently, the periphery of the opening of the reflecting material formed surrounding the periphery of the LED element and the individual surrounded by the opening. It is desirable to minimize the distance (gap width) between the LED element and the outer edge as much as possible.

  However, the processing accuracy of the position and size of the opening of the reflector and the positional accuracy of mounting the LED element both have certain limits. Specifically, it was extremely difficult to make the gap width about 0.1 mm or less.

  On the other hand, since an LED backlight incorporating an LED module is one in which a large number of LED elements are mounted by soldering, a lighting inspection before shipment of the final product is essential. However, for example, when the gap width is narrowed to the limit value in processing technology of about 0.1 mm, it is not possible to visually observe the bonding state of the solder portion located below the reflector. When there is even one defective element, it is necessary to destructively peel off the reflective material and other laminated members and reinspect the bonding state of the solder portion. Since this destructive inspection leads to an increase in work load and productivity reduction, in order to avoid this, even if sacrificing the optical characteristics, emphasizing ease of lighting inspection, the above gap width is dared. In some cases, it was designed to leave a width of about 0.6 mm.

JP 2010-155853 A

  The present invention has been made in view of the situation as described above, and is an LED module used for constituting a direct type backlight, which has high luminance as a light source and lighting inspection at the time of product shipment, etc. An object of the present invention is to provide an LED module that is compatible with ease.

  As a result of intensive research, the present inventors have formed a form in which an LED element-enclosing side wall that surrounds the LED element and rises is formed with respect to a specific portion of the periphery of the opening formed in the reflective material arranged in the LED module, As a structure in which the inner surface of the LED element surrounding side wall is attached to the side surface of the LED element, the gap width between the individual LED elements and the peripheral edge of the opening of the reflector is minimized, and conduction at the LED element junction is performed. The present invention has been completed by finding that the above problem can be solved by forming a gap width that allows the state of the solder portion to be visually recognized at the periphery of the LED element in a specific direction with respect to the direction. . Specifically, the present invention provides the following.

  (1) Covering the area excluding the LED element substrate on which the metal wiring part is formed on the surface of the support substrate, the plurality of LED elements mounted on the metal wiring part, and the LED element mounting area And a reflective material laminated on the LED element substrate, wherein the LED element is a part of the metal wiring part and is formed at a position facing and spaced apart from each other. Mounted on a mounting portion consisting of a pair of conductive plates, and the reflective material is made of a flexible resin sheet, and an opening is formed at a position corresponding to the mounting region. A portion of the resin sheet is bent toward the top of the LED element at a portion of the periphery of the opening that is parallel or substantially parallel to the conduction direction between the pair of conductive plates. stand up An LED element surrounding side wall is formed, and at least a part of an inner surface including the top of the LED element surrounding side wall is in contact with a side surface of the LED element, and among the peripheral edges of the opening, In the portion parallel to or substantially parallel to the direction orthogonal to the conduction direction, the LED element surrounding side wall is not formed, and in the plan view from the light emitting surface side of the LED module, out of the periphery of the opening An LED module in which a solder part fixing the LED element to the metal wiring part is visibly exposed in the vicinity of a part where the LED element surrounding side wall is not formed.

  In the invention of (1), individual portions located in the opening only in the portion parallel to or substantially parallel to the conduction direction of the mounted LED element, of the periphery of the opening of the reflector disposed on the LED element substrate. The LED element surrounding side wall surrounding the LED element is formed, and at least a part of the inner surface including the top of the LED element surrounding side wall is attached to the side surface of each LED element. Thereby, in the LED module used to construct a direct type backlight, the use efficiency of light emitted from the LED element by reducing the gap width between each LED element and the peripheral edge of the opening of the reflecting material Can be increased. On the other hand, a minimum gap width is intentionally left in the portion other than the above in the periphery of the opening, and the LED element 2 is connected to the metal wiring portion 13 (conductive plate 131, conductive plate 131, in a plan view from the light emitting surface side of the LED module 10). 132), the solder part 17 fixed to 132) is exposed so as to be visible. Thereby, while enjoying the above-mentioned effect of improving the utilization efficiency of the light emitted from the LED element, the conductive state of the solder part is destroyed without destroying any part of the LED module including the reflective material and other members. An LED module that can be inspected, that is, an LED module that is excellent in optical characteristics and capable of nondestructive lighting inspection.

  Here, the “LED element mounting region” in the present specification is a region composed of a portion to be a joint portion to the metal wiring portion of the LED element on the LED element substrate and its peripheral portion, and the mounting of the LED element. It refers to a region immediately below a space that is at least required as an optical path to the outside of the light emitted from the LED element.

  (2) The LED module according to (1), wherein a bending stress based on ASTM-D790 of the resin sheet forming the reflective material is 10 MPa or more and 40 MPa or less.

  In invention of (2), it was set as the structure which limits the bending stress of the material resin sheet of the reflector in invention of (1) to a predetermined range. Thereby, a part of flexible resin sheet which comprises a reflecting material can be easily bent and made to follow. In addition, the preferred form of the subordinate LED element surrounding side wall can be easily maintained.

  (3) An adhesive layer is formed on the back surface of the reflective material, and the reflective material is adhered to the LED element substrate and the LED element via the adhesive layer. LED module as described in 2).

  In the invention of (3), an adhesive layer is formed on the inner surface of the reflecting material, and by sticking through this layer, the position of the reflecting material on the LED element substrate and the LED on the LED element surrounding side wall are reduced. A configuration in which peeling from the side surface of the element can be prevented more reliably. Thereby, the effect of the brightness improvement of the direct type LED backlight using the LED module of (1) or (2) can be stably maintained over a longer period.

  (4) The LED element-enclosing side wall stands up substantially perpendicularly to the surface of the LED element substrate at the periphery of the opening, and the entire surface of the inner surface of the LED element-enclosing side wall is the LED element. The LED module according to any one of (1) to (3), which is attached to a side surface of the LED.

  In the invention of (4), the contact surface between the inner surface of the LED element surrounding side wall and the side surface of the LED element in the LED module according to any one of (1) to (3) is maximized, It is possible to further enhance the stability of adhesion or sticking of both parts at this interface.

  (5) Only a part of the back surface of the LED element surrounding side wall near the top side is in contact with a part of the LED element side wall near the top, and the LED element surrounding side wall has the opening portion. The LED module according to any one of (1) to (4), wherein the LED module rises in a tapered shape with an opening diameter narrowing from the periphery of the LED toward the top of the LED element.

  In the invention of (5), the direction in which the reflecting surface formed by the LED element surrounding side wall in the LED module according to any one of (1) to (3) can be reflected from the vicinity of the light source toward the far side of the light source. Formed towards. Thereby, the diffusion of light is promoted toward the outer side when each LED element is the center, and the luminance uniformity over the entire light emitting surface of the LED module according to any one of (1) to (3) is achieved. Can be improved.

  (6) The LED module according to (5), wherein the LED element surrounding side wall has a concave curved surface shape convex toward the support substrate side.

  In invention of (6), the reflective surface which the LED element surrounding side wall in the LED module as described in (5) comprises was made into the reflective surface which consists of concave curved surface shape. Thereby, in LED backlight provided with the LED module as described in (5), the light with higher brightness | luminance which will reflect in a position nearer to an LED element can be reflected toward a distant place. Thereby, it is possible to improve the uniformity of the brightness of the entire surface light source while maintaining a higher brightness.

  (7) The LED module according to any one of (1) to (6), wherein the LED substrate is a flexible substrate because the support substrate is a flexible resin film.

  In the invention (7), the LED element substrate constituting the LED module according to any one of (1) to (6) is not a rigid rigid substrate but a so-called flexible substrate. According to this, the LED backlight which enjoys the effect which the LED module in any one of (1) to (6) show | plays, and is excellent in the shape followability to the installation surface of various shapes Can be configured.

  (8) An LED display device comprising a backlight comprising the LED module according to any one of (1) to (7).

  In invention of (8), it was set as the LED display apparatus provided with the LED backlight comprised using the LED module in any one of (1) to (7). According to this, an LED display device including a high-brightness LED backlight can be obtained by the effect produced by any one of the LED modules (1) to (7).

  (9) The lighting inspection method for an LED module according to any one of (1) to (7), wherein the LED module is exposed in the vicinity of the periphery of the opening by a plan view from the light emitting surface side of the LED module. A method for inspecting lighting of an LED module, comprising a step of inspecting a conduction state of the solder part without destroying any part of the LED module.

  In the invention of (9), by making the LED module as described in any one of (1) to (7), the effect of improving the use efficiency of emitted light that can be achieved by these LED modules is achieved. In the lighting inspection performed before product shipment, the conduction state of the solder portion exposed in the vicinity of the periphery of the opening portion in a plan view from the light emitting surface side of the LED module is inspected by nondestructive inspection while enjoying the product. be able to.

  According to the present invention, there is provided an LED module that is used for constituting a direct type backlight, and has both high luminance as a light source and easy lighting inspection at the time of product shipment. can do.

It is a top view which shows typically an example of the LED module of this invention. FIG. 2 is a diagram illustrating a state of a mounting portion of an LED element in the LED module of the present invention in a state where a reflective material in the LED module of FIG. 1 is removed. FIG. 2 is an enlarged cross-sectional view schematically showing a cross section of the AA portion of FIG. 1, and is a drawing for explaining a layer configuration of the LED module of the present invention. It is drawing with which it uses for description of the layer structure in other embodiment of the LED module of this invention. It is drawing with which it uses for description of the layer structure in other embodiment of the LED module of this invention. It is a partial expansion top view of the reflecting material which can be preferably used for the LED module of this invention. It is the elements on larger scale of the LED mounting area periphery part in other embodiment of the LED module of this invention. FIG. 8 is a partially enlarged front view and a side view of a peripheral portion of an LED mounting region in the embodiment shown in FIG. 7 of the LED module of the present invention. It is drawing which uses for description of the manufacturing method of the LED module of this invention. It is a perspective view which shows typically the outline of the layer structure of the LED display apparatus which uses the LED module of this invention.

  Hereinafter, embodiments of the LED module and the LED display device of the present invention will be described. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present invention.

<LED module>
As shown in FIGS. 1 to 3, the LED module 10 of the present invention is a light source module in which a surface light source is configured by mounting a plurality of LED elements 2 in a matrix on an LED element substrate 1. This light source module can be preferably used mainly as a light source of a direct type LED backlight.

  The LED element substrate 1 constituting the LED module 10 has a metal wiring portion 13 formed on the surface of a support substrate 11 and is flexible in a manner covering other portions except for the mounting area of the plurality of LED elements 2. A reflective material 15 made of a resin sheet having properties is laminated on the LED element substrate 1. In addition, as shown in FIG. 3, the LED module 10 is preferably such that the insulating protective film 14 is formed so as to cover the metal wiring portion 13, and in this case, the reflective material 15 is the insulating protective film. 14 is arranged.

  In the “LED element mounting region” of the LED module 10, the LED element 2 is mounted on the metal wiring part 13 via the solder part 17, and in this state, of the periphery of the opening part of the reflector 15. The LED element-enclosing side wall 151 that follows from the periphery of the opening of the reflector 15 is formed only in a portion parallel or substantially parallel to the conduction direction between the pair of conductive plates 131 and 132. The inner surface of the surrounding side wall 151 is in contact with the side surface of the LED element 2.

  In the conventional LED module, a gap width of about 0.1 mm or more is normally unavoidable between the peripheral edge of the opening of the reflector and the side surface of the LED element located in the opening as described above. Were present. However, in the LED module 10 of the present invention, the gap width can be reduced to 0 by bringing at least a part of the inner surface including the top of the LED element surrounding side wall 151 into contact with the side surface of the LED element 2. it can. Here, “attachment” in the present specification refers to all aspects in which the attachment object is in contact with no gap, and the attachment structure is desired in the overall configuration of the article (for example, LED module). A mode having stability is sufficient, and includes a mode of contact that does not necessarily have a chemical bonding structure such as an adhesive or an adhesive. For example, due to the elasticity of the resin sheet constituting the reflecting material, a very small part from the top of the inner surface of the LED element surrounding side wall 151 or between the top surface of the LED element surrounding side wall 151 and the inner surface. The aspect in which the corners are in line contact and the contact state with the LED element 2 is maintained is also one aspect of the above “attachment”.

  However, the adhesion between the inner surface of the LED element-enclosing side wall 151 of the reflector 15 and the side surface of the LED element 2 located in the opening is as shown in FIG. It is more preferable that the mode is via. Details of the reflector 15 having the adhesive layer 16 will be described later.

  On the other hand, in the “LED element mounting region” of the LED module 10, as shown in FIG. 7, the LED element surrounding side wall 151 is formed in the periphery of the opening in the plan view from the light emitting surface side of the LED module 10. The LED element 2 is fixed to the metal wiring portion 13 (conductive plates 131 and 132) in the vicinity of the portion that is not present, that is, in the vicinity of the portion of the periphery of the opening that is parallel or substantially parallel to the direction orthogonal to the conduction direction. The solder part 17 is exposed so as to be visible. By adopting such a configuration, while enjoying the above-described effect of improving the utilization efficiency of light emitted from the LED element 2, the conduction state of the solder part including the reflector 15 and other members is included in the LED module 10. It can be set as the LED module which can test | inspect without destroying any part, ie, the LED module in which the lighting test | inspection by a nondestructive test | inspection is possible.

  The LED module 10 having the above-described configuration can be preferably used as a light source module constituting a direct type LED backlight in the LED display device 100 shown in FIG. 10 and various other LED display devices in general. .

  When a direct-type LED backlight is configured using the LED module 10, a transmissive reflector or a diffuser plate (both not shown) are located at a predetermined distance from the light emitting surface of the LED element 2. It is common to further arrange an optical member such as

[Substrate for LED element]
Next, the detail of the board | substrate 1 for LED elements which comprises the LED module 10 is demonstrated. As shown in FIGS. 1 to 3, the LED element substrate 1, which is a wiring board on which the LED element 2 is mounted, has a conductive metal wiring portion 13 made of metal foil or the like on the surface of a support substrate 11 made of resin film or the like. Are laminated via the adhesive layer 12. An insulating protective film 14 is formed on the support substrate 11 and the metal wiring portion 13 except for the “LED element mounting region”. The reflective material 15 is laminated on the outermost surface of the LED module 10 on the light emitting surface side so as to cover the region excluding the “LED element mounting region” on the support substrate 11 and the metal wiring part 13.

(Support substrate)
As the support substrate 11, various substrate materials conventionally used as a support substrate for LED element substrates can be appropriately used. However, this substrate material is preferably a flexible resin film. In the present specification, “having flexibility” means that “the radius of curvature is at least 1 m or less, preferably 50 cm, more preferably 30 cm, further preferably 10 cm, particularly preferably 5 cm. Say.

  When a flexible resin film is used as the material for the support substrate 11, the film is required to have high heat resistance and insulation. As such a resin film, a resin film made of polyimide (PI), polyethylene naphthalate (PEN) or the like excellent in heat resistance, dimensional stability during heating, mechanical strength, and durability can be preferably used. Especially, what consists of polyethylene naphthalate (PEN) which improved heat resistance and dimensional stability by performing heat resistance improvement processes, such as annealing treatment, can be used especially preferably. Further, a resin film made of polyethylene terephthalate (PET) whose flame retardancy is improved by adding a flame retardant inorganic filler or the like can also be preferably used as the material of the support substrate 11.

  When the substrate material for forming the support substrate 11 is a resin film made of a thermoplastic resin, the heat shrinkage start temperature is 100 ° C. or higher, or the temperature becomes 100 ° C. or higher due to the annealing treatment or the like. Thus, it is preferable to use one having improved heat resistance. Usually, the peripheral portion of the element may reach a temperature of about 90 ° C. due to heat generated from the LED element. From this viewpoint, it is preferable that the resin film forming the support substrate has heat resistance equal to or higher than the above temperature. In this specification, “thermal shrinkage start temperature” means that a sample film made of a thermoplastic resin to be measured is set in a TMA apparatus, a load of 1 g is applied, and the temperature is increased to 120 ° C. at a rate of temperature increase of 2 ° C./min. Measure the amount of shrinkage (in%) at that time, output this data and record the temperature and amount of shrinkage, read the temperature that deviates from the 0% baseline due to shrinkage, and heat shrink the temperature This is the starting temperature.

The support substrate 11 is required to be a resin having a high insulating property that can provide the insulating property necessary for the LED element substrate 1 during integration as the LED module 10. In general, the support substrate 11 has a volume resistivity of preferably 10 ¹⁴ Ω · cm or more, and more preferably 10 ¹⁸ Ω · cm or more.

  The thickness of the support substrate 11 is not particularly limited. However, the thickness of the support substrate 11 is not less than 12 μm and not more than 500 μm from the viewpoint of not being a bottleneck as a heat dissipation path, having heat resistance and insulation, and balance of manufacturing costs. Is preferable, and more preferably 20 μm or more and 250 μm or less. Also, the thickness is preferably within the above-mentioned thickness range from the viewpoint of maintaining good productivity when manufacturing by the roll-to-roll method.

(Adhesive layer)
In the LED element substrate 1, the formation of the metal wiring portion 13 on the surface of the support substrate 11 is preferably performed by a dry laminating method with the adhesive layer 12 interposed. As the adhesive forming the adhesive layer 12, a known resin adhesive can be used as appropriate. Of these resin adhesives, acrylic, urethane, polycarbonate, or epoxy adhesives can be particularly preferably used.

(Metal wiring part)
As shown in FIGS. 2 and 3, the metal wiring portion 13 is a wiring pattern formed on the surface of the support substrate 11 constituting the LED element substrate 1 by a conductive base material made of various metal foils.

  The metal wiring part 13 is a form in which a basic unit of mounting shown in FIG. 3, that is, a basic unit composed of a combination of a pair of conductive plates 131 and 132 is repeatedly formed in the X direction and the Y direction perpendicular thereto. It is preferable. By mounting a plurality of LED elements 2 in such a wiring pattern in a matrix, a surface light source of a direct type LED backlight can be configured.

  As shown in FIG. 3, each LED element 2 is a part of the metal wiring portion 13, and is mounted on a mounting portion composed of a pair of conductive plates 131 and 132 formed at positions facing each other while being separated from each other. It is mounted via the solder part 17.

  The metal wiring portion 13 is not only a portion serving as a basic unit of the above-described mounting, but also a connector wiring for connecting between conductive plates arranged in different rows or columns in a matrix arrangement, or a row or column end portion. 1 includes a terminal for electrical connection between the LED module 10 and an external power source or the like. In the LED element substrate 1, the degree of freedom in designing the conductive plates 131 and 132 constituting the metal wiring portion 13, the connector wiring, the arrangement of the terminals, and the combination thereof is high. Any connection in parallel is also possible, and wiring can be obtained by optimally combining both connections according to the characteristics required of the LED module 10 after mounting.

The metal thermal conductivity λ constituting the metal wiring part 13 is preferably 200 W / (m · K) or more and 500 W / (m · K) or less, and preferably 300 W / (m · K) or more and 500 W / (m · K) or less. More preferred. The metal resistivity R constituting the metal wiring portion 13 is preferably 3.00 × 10 ⁻⁸ Ωm or less, and more preferably 2.50 × 10 ⁻⁸ Ωm or less. Here, the measurement of the thermal conductivity λ can use, for example, a thermal conductivity meter QTM-500 manufactured by Kyoto Electronics Industry Co., Ltd., and the measurement of the electrical resistivity R can be performed, for example, a 6517B type electrometer manufactured by Keithley. Can be used. According to this, for example, in the case of copper, the thermal conductivity λ is 403 W / (m · K), and the electrical resistivity R is 1.55 × 10 ⁻⁸ Ωm. Thereby, both heat dissipation and electrical conductivity can be achieved. More specifically, since the heat dissipation from the LED element is stabilized and an increase in electrical resistance can be prevented, the variation in light emission between the LEDs is reduced, the LED can stably emit light, and the LED life is also extended. . Further, since deterioration of peripheral members such as the substrate due to heat can be prevented, the product life of the image display device itself in which the LED element substrate is incorporated as a backlight can be extended.

  Examples of the metal constituting the metal wiring part 13 include aluminum, gold, silver, and copper. The thickness of the metal wiring part 13 should just be set suitably according to the magnitude | size of the electric current resistance requested | required of the board | substrate 1 for LED elements, etc., Although it does not specifically limit, 10 micrometers-50 micrometers in thickness are mentioned as an example. From the viewpoint of improving heat dissipation, the thickness of the metal wiring portion 13 is preferably 10 μm or more. Further, if the metal layer thickness is less than the lower limit, the influence of the thermal contraction of the support substrate 11 is large, and the warp after the treatment is likely to increase during the solder reflow process. Is preferably 10 μm or more. On the other hand, when the thickness is 50 μm or less, sufficient flexibility of the LED element substrate can be maintained, and a decrease in handling property due to an increase in weight can be prevented.

(Insulating protective film)
As the resin composition for forming the insulating protective film 14, various conventionally known thermosetting inks can be used. The thermosetting ink preferably has a thermosetting temperature of about 120 ° C. or less. Specifically, an ink that can preferably use an insulating ink having a polyester resin, an epoxy resin, an epoxy resin and a phenol resin, an epoxy acrylate resin, a silicone resin, a fluorine resin, or the like as a base resin. As a representative example of Of these, polyester-based thermosetting insulating ink is particularly preferable as a material for forming the insulating protective film 14 of the LED element substrate 1 because of its excellent flexibility. In addition, the “thermosetting temperature” in the present specification is the measurement and calculation of the temperature at the rising position of the thermosetting reaction when the thermosetting resin to be measured is heated, and that temperature is the thermosetting temperature. .

  Further, by adding a white pigment to the thermosetting ink for forming the insulating protective film 14 to make it a white ink, the insulating protective film 14 can be a light reflecting layer having a light reflecting function. it can. As a white pigment used in this case, an inorganic white pigment such as titanium dioxide can be exemplified as a preferred pigment.

(Reflective material)
The reflective material 15 is a reflective member having high reflectivity mainly with respect to light in the visible light wavelength range, and as described in detail below, the LED element surrounding side wall 151 can be formed on the periphery of the opening. What is necessary is just to consist of a resin sheet which has flexibility. Such a reflective material 15 covers the region excluding the LED element mounting region for the purpose of improving the light emission capability of the LED backlight using the LED module 10, and on the outermost surface on the light emitting surface side of the LED module 10, Laminated.

  As shown in FIGS. 1 and 3, the reflector 15 has an opening at a position corresponding to the LED element mounting region. Formation of the opening part in the resin sheet which comprises the reflecting material 15 can be based on conventionally well-known various drilling processes, such as a punching process and a laser process.

  In addition, when the LED element 2 is a rectangular parallelepiped shape as shown in FIG. 3, the shape of the opening is preferably a rectangular shape corresponding to the outer peripheral shape. The LED module of the present invention can be particularly preferably applied when the outer peripheral shape of the side surface of the LED element is such a rectangular shape. However, when the LED element 2 has a cylindrical shape, it is possible to enjoy the same effect by making the shape of the opening corresponding to the circular shape. It is within the scope of the present invention. When the outer peripheral shape of the side surface of the LED element is thus circular or elliptical, the shape of the opening is changed to a shape substantially similar to each of those shapes, and furthermore, a resin sheet having a large stretchability is used. As in the case of the LED module 10 in which the rectangular LED element 2 is mounted by forming a part of the side wall depending on the extension of the sheet, or by making an appropriate notch process around the opening. The use efficiency of light emitted from the LED element can be improved by eliminating the gap width described above. In the following, details of the reflector 15 and the LED element surrounding side wall 151 when the LED element 2 has a rectangular parallelepiped shape as shown in FIG. 3, that is, when the shape of the opening is rectangular will be described.

  As shown in FIG. 3, the LED element surrounding side wall 151 is formed in the reflector 15 at the periphery of each opening. The LED element-enclosing side wall 151 is formed by bending a part of the resin sheet constituting the reflector 15 toward the top portion of the LED element 2 mounted in the opening and standing up.

  In the LED module 10, the LED element surrounding side wall 151 is in contact with the side surface of the LED element 2. Thereby, the LED module 10 includes the LED element 2 and the peripheral edge of the opening of the reflector 15 that cause a reduction in the utilization efficiency of the light emitted from the LED element 2 in the portion where the LED element surrounding side wall 151 is formed. It is made the structure which eliminated the gap width between.

  As a form of the LED element surrounding side wall 151, for example, as shown in FIG. 4, a form that is substantially perpendicular to the surface of the LED element substrate 1 is a preferred embodiment of the LED element surrounding side wall 151. It can be illustrated. In this embodiment, substantially the entire inner surface of the LED element surrounding side wall 151 is brought into contact with the side surface of the LED element 2, and the contact stability between the inner surface of the LED element surrounding side wall 151 and the side surface of the LED element 2 is stabilized. Can be higher.

  As the form of the LED element surrounding side wall 151, for example, as shown in FIG. 5, a form in which the width of the opening narrows from the periphery of the opening toward the top of the LED element 2 is formed. 151 can be exemplified as another preferred embodiment. In this form, only a part of the inner surface of the LED element surrounding side wall 151 near the top side is in contact with a part of the side of the LED element near the top. In this embodiment, it is possible to promote the diffusion of light emitted from the individual LED elements 2 and to improve the uniformity of luminance in the entire light emitting surface of the LED module 10.

  Further, when the LED element surrounding side wall 151 has a tapered shape as described above, a space E is formed between the solder portion 17 and the reflector 15 or the adhesive layer 16 as shown in FIG. By doing so, it is possible to avoid contact between the reflective member 15 and the solder portion 17 that becomes high temperature due to heat generated when the LED element 2 is turned on, and to prevent deterioration of the reflective material due to high heat.

    Further, as shown in FIG. 5, the LED element surrounding side wall 151 may further include a concave reflecting portion 152 having a concave curved surface shape convex toward the support substrate 11 side. According to the LED element surrounding side wall 151 having such a configuration, light with higher luminance that is reflected at a position closer to the LED element can be reflected toward a farther place. Thereby, in the LED module 10, the uniformity of the brightness | luminance as the whole surface light source can be improved, hold | maintaining higher brightness | luminance.

  In addition, about the gap G (FIG. 4) of both height which is a difference of the vertical direction position of the re-top part of LED element surrounding side wall 151, and the vertical direction position of the top part of LED element 2 which has contacted this, The optical characteristics and the size in the case of improving the luminance are preferably within 0.1 mm, and most preferably 0.

  Further, as shown in FIG. 6, the reflecting material 15 may be formed by forming a plurality of cuts 153 for facilitating the formation of the LED element surrounding side wall 151 at the periphery of the opening. This notch 153 makes it easier to form the LED element surrounding side wall 151 that follows the position surrounding the LED mounting region by bending the resin sheet constituting the reflector 15 along the line including the end point portion. In addition, these can be formed while maintaining higher position and shape accuracy.

  The resin sheet constituting the reflector 15 may be a member having reflectivity for reflecting the light emitted from the LED element 2 and guiding it in a predetermined direction in terms of optical characteristics. In this respect, more specifically, the reflector 15 preferably has a light reflectance of 95% or more, more preferably 97% or more, for light having a wavelength of 450 nm to 650 nm. Moreover, in order to improve the uniformity of the luminance on the entire light emitting surface of the LED module, it is more preferable to have a reflecting surface with a high diffuse reflectance. As a preferable index of diffuse reflectance, a resin sheet having a reflective surface with a regular reflectance of 30% or less can be cited as an example of a preferred resin sheet.

Here, the definitions of the light reflectance, diffuse reflectance, and regular reflectance in the present specification are as follows.
The reflectance at 450 nm to 650 nm was measured, and the numerical values at each wavelength were averaged to obtain the reflectance and diffuse reflectance. Further, the regular reflectance was calculated from the reflectance and diffuse reflectance at each wavelength by the following formula (1), and the numerical values at each wavelength were averaged to obtain the regular reflectance. In addition, since it is difficult to strictly measure the absolute reflectance, the relative reflectance with the reference standard sample is usually used for the reflectance. In the present invention, barium sulfate is used as a comparative standard sample. The reflectance in the present invention is determined by attaching an integrating sphere attachment device (for example, integrating sphere unit ISN-723) to a spectrophotometer (for example, JASCO Corporation V-670DS), using barium sulfate as a standard plate, and using 100 as the standard plate. It is a value obtained by measuring the relative reflectance in%.

  Regular reflectance (%) = reflectance (%) − diffuse reflectance (%) (1)

  If the light reflectance of the reflector 15 is 95% or more, most of the light leaking from the LED element 2 to the side and back sides of the light emitted from the LED element 2 is reflected to the display screen side. Can do. And thereby, the light emitted from the LED element 2 can be utilized very efficiently.

  The regular reflectance of the reflector 15 calculated by the above method is preferably 30% or less, and more preferably 1% or more and 25% or less. By increasing the ratio of the diffuse reflectance to the reflectance of the light as much as possible, the light emitted from the LED element 2 is uniformly diffused over the entire screen of the LED display device 100 to reduce luminance unevenness and improve the image quality. be able to. From the viewpoint of improving the diffuse reflectance, the smaller the regular reflectance, the better. However, since a special material such as a filler having a very narrow particle size distribution or a manufacturing method is required, it is not preferable from the viewpoint of cost. When the regular reflectance exceeds 30%, the ratio of the diffuse reflectance decreases, and the halation due to light reflection becomes too strong, which is not preferable because the display screen feels dazzling.

  In the LED module 10, the reflecting material 15 is also required to have a specific bending stress as a mechanical strength in addition to the above-described optical property requirements. A part of the resin sheet constituting the reflecting material 15 can be easily bent to form the LED element surrounding side wall 151, and further, the shape of the side wall can be easily maintained. Is preferred. In order to satisfy this requirement, the resin sheet forming the reflecting material 15 is preferably a resin sheet having a bending stress based on ASTM-D790 of 10 MPa or more and 40 MPa or less. When the bending stress is less than 10 MPa, it is difficult to stably hold the LED element-enclosed side wall 151 and the attachment to the side surface of the LED element 2 particularly when the adhesive layer 16 is not present. Even in the case where the adhesive layer 16 is present, this bending stress causes the reflecting material 15 to be bent and deformed to form the LED element surrounding side wall 151 and to maintain its preferred shape. Therefore, the pressure is preferably 10 MPa or more. On the other hand, when the bending stress exceeds 40 MPa, it is not preferable in that it is difficult to form the LED element surrounding side wall 151 having a desired shape by supporting the reflector 15.

  Examples of the resin sheet for making the reflector 15 satisfy the above requirements concerning the optical characteristics and mechanical strength include, for example, a foamed resin film using an olefin resin, a foam type white polyester, and silver. A vapor deposition polyester etc. can be mentioned. Any one of these resin sheets can be appropriately selected according to the form and application of the LED display device as the final product and the required specifications. For example, when the LED module 10 is used as a backlight of an in-vehicle LED display device that is relatively small but has high luminance and is required to follow the shape of various installation surfaces, Among these, a foamed resin film using an olefin resin can be preferably used. In addition, since in-vehicle LED display devices are also required to be flame retardant, in this respect as well, olefin-based foamed resins such as foamed resins based on polypropylene-based resins that have self-digestibility are used for this purpose. It is extremely suitable as a material for a display device.

  As an example of a foamed resin sheet that can be particularly preferably used as the resin sheet constituting the reflector 15, a resin sheet having the same composition as the “foamed resin film” disclosed in International Publication No. 2007/132826 is preferable. Specific examples can be given. This foamed resin sheet can be obtained by stretching and molding a resin composition containing an olefin resin as a base resin and containing a filler, as disclosed in the above document. Hereinafter, the detail of this foamed resin sheet is demonstrated.

  Among the olefin resins, the base resin of the foamed resin sheet constituting the reflecting material 15 is particularly preferably a polypropylene resin such as a propylene homopolymer or a propylene-ethylene copolymer. In addition, ethylene resins such as high-density polyethylene can also be used. These may be used in combination of two or more. Among these, it is more preferable to use a propylene resin from the viewpoint of water resistance, water repellency, chemical resistance, production cost, and the like.

  Copolymerization of propylene homopolymer, propylene as a main component, and α-olefin such as ethylene, 1-butene, 1-hexene, 1-heptene, 4-methyl-1-pentene as the propylene resin Coalescence can be used. The stereoregularity is not particularly limited, and isotactic or syndiotactic and those showing various degrees of stereoregularity can be used. The copolymer may be a binary system, a ternary system, or a quaternary system, and may be a random copolymer or a block copolymer.

  The foamed resin sheet constituting the reflective material 15 preferably contains 20% by mass to 75% by mass of filler. If the filler contained in the foamed resin sheet is 75% by mass or less in total, the foamed resin sheet has high strength, and it is easy to obtain one that can withstand practical use. When the filler content is 20% by mass or more, it is easy to form sufficient pores, and preferable diffuse reflectance is easily obtained.

  As said filler contained in said foamed resin sheet, various inorganic fillers or organic fillers can be used. Examples of the inorganic filler include heavy calcium carbonate, precipitated calcium carbonate, calcined clay, talc, titanium oxide, barium sulfate, aluminum sulfate, silica, zinc oxide, magnesium oxide, diatomaceous earth, and the like.

  According to the reflective material 15 made of the above foamed resin sheet, by setting the thickness of the reflective material 15 in the range of 50 μm or more and 200 μm or less, the light reflectance is 95% or more and the regular reflectance is 30%. The following optical characteristics can be imparted to the reflector 15. Further, if necessary, the reflective material 15 can be given a higher reflectance by making the reflective material 15 thicker.

  Further, by setting the thickness of the reflective material 15 made of the foamed resin sheet to be in the range of 50 μm to 200 μm, the bending stress based on ASTM-D790 of the reflective material 15 is optimized in the range of 10 MPa to 40 MPa. can do.

  The above-mentioned foamed resin sheet has a larger surface friction than a general non-foamed resin sheet. Therefore, when such a foamed resin sheet is used as the reflective material 15, compared with a case where a non-foamed resin sheet having a smooth surface is used, the interface between the back surface of the reflective material 15 and the side surface of the LED element 2 is attached. Even when there is no adhesive layer or when the contact area is very small, it is easy to maintain the above-mentioned contact state in a preferable shape by the elasticity of the resin sheet and the above frictional force.

  The reflective material 15 may be one in which an adhesive layer 16 is formed on the inner surface when laminated on the LED module 10, that is, on the back surface side opposite to the surface exposed on the outermost surface of the LED module. preferable. Before the reflecting material 15 is finally fixed by another fixing means in the module by adopting a configuration in which the reflecting material 15 is adhered to the surface of the LED element substrate 1 through the adhesive layer 16. It is possible to prevent misalignment at this stage. Moreover, the LED element surrounding side wall 151 which is a part of the reflecting material 15 is similarly attached to the side surface of the LED element 2 via the adhesive layer 16, so that the adhesion between both surfaces is achieved. As a result, the long-term stability of the brightness enhancement effect that can be achieved by the LED module 10 can be enhanced.

  The pressure-sensitive adhesive layer 16 is preferably configured using a double-sided adhesive tape having heat resistance enough to withstand a high temperature of about 100 ° C. For example, the pressure-sensitive adhesive layer 16 is configured by using an acrylic adhesive double-sided adhesive tape having such heat resistance, so that the LED element surrounding side wall 151 is exposed from the side surface of the LED element 2 due to the high temperature emitted from the LED element 2. It can prevent peeling. As such a double-sided adhesive tape having heat resistance, for example, a commercially available “heat-resistant double-sided adhesive tape: No. 5919ML (manufactured by Nitto Denko Corporation)” or the like can be used.

[LED element]
The LED element 2 is a light emitting element that utilizes light emission at a PN junction where a P-type semiconductor and an N-type semiconductor are joined. There are proposed a structure in which a P-type electrode and an N-type electrode are provided on the upper and lower surfaces of the element and a structure in which both the P-type and N-type electrodes are provided on one side of the element. The LED element 2 having any structure can be used for the LED module 10 of the present invention, but among the above, an LED element having a structure in which both the P-type and N-type electrodes are provided on one side of the element is particularly preferably used. it can.

  In order to display a high-quality image without unevenness in the LED module 10, in order to diffuse light having directivity emitted from each LED element serving as a light source uniformly over the entire light emitting surface of the backlight, In the substrate 1, a light diffusion lens (not shown) may be attached to each LED element 2. The light diffusing lens is a light diffusing lens that diffuses the light emitted from the LED element 2, and is an aspheric lens, for example. For example, it can be formed of a transparent resin material such as polymethyl methacrylate (PMMA), polycarbonate (PC), epoxy resin (EP), or transparent glass. For example, an optical member capable of producing a desired light diffusion effect can be used as appropriate, including a conventional known lens member disclosed in JP2013-12417A.

[Solder part]
In the LED element substrate 1, the metal wiring part 13 and the LED element 2 are joined through the solder part 17. The bonding method using solder can be roughly classified into two methods, a reflow method and a laser method.

<Method for producing LED element substrate>
The LED element substrate 1 can be manufactured by an etching process, which is one of the conventionally known methods for manufacturing an electronic substrate, and a reflector placement process unique to the present invention.

[Etching process]
A laminated body made of a material is obtained by laminating a metal wiring portion 13 such as a copper foil as a material of the metal wiring portion 13 on the surface of the support substrate 11 subjected to a heat treatment such as an annealing treatment as necessary. As a lamination method, a metal foil is adhered to the surface of the support substrate 11 with an adhesive, or a plating method or a vapor deposition method (sputtering, ion plating, electron beam evaporation, Examples thereof include a method of depositing the metal wiring portion 13 by vacuum deposition, chemical vapor deposition, or the like. From the viewpoint of cost and productivity, a method of bonding the metal foil to the surface of the support substrate 11 with a urethane-based adhesive is advantageous.

  Next, an etching mask patterned into a shape required for the metal wiring portion 13 is formed on the surface of the metal foil of the above laminate. In the future, the etching mask is provided so that the wiring pattern forming portion of the metal foil to be the metal wiring portion 13 is free from corrosion by the etching solution. The method for forming the etching mask is not particularly limited. For example, the etching mask may be formed on the surface of the laminated film by developing after exposing a photoresist or dry film through the photomask, an inkjet printer, or the like. An etching mask may be formed on the surface of the laminated film by the printing technique.

  Next, the metal foil in a portion not covered with the etching mask is removed with an immersion liquid. Thereby, parts other than the location used as the metal wiring part 13 are removed among metal foil.

Finally, the etching mask is removed using an alkaline stripping solution. As a result, the etching mask is removed from the surface of the metal wiring portion 13.
(Etching process)
On the surface of the support substrate 11, a metal wiring part 13 such as a copper foil used as the material of the metal wiring part 13 is stacked to obtain a laminate used as the material of the LED element substrate 1. As a lamination method, a metal foil is adhered to the surface of the support substrate 11 with an adhesive, or a plating method or a vapor deposition method (sputtering, ion plating, electron beam evaporation, Examples thereof include a method of depositing the metal wiring portion 13 by vacuum deposition, chemical vapor deposition, or the like. From the viewpoint of cost and productivity, a method of bonding the metal foil to the surface of the support substrate 11 with a urethane-based adhesive is advantageous.

  Next, an etching mask patterned in the shape of the metal wiring portion 13 is formed on the surface of the metal foil of the laminate. In the future, the etching mask is provided so that the wiring pattern forming portion of the metal foil that will become the metal wiring portion 13 is free from corrosion by the etching solution. The method for forming the etching mask is not particularly limited. For example, the etching mask may be formed on the surface of the laminated sheet by exposing the photoresist or the dry film through the photomask and then developing the ink mask. An etching mask may be formed on the surface of the laminated sheet by a printing technique such as.

  Next, the metal foil in a portion not covered with the etching mask is removed with an immersion liquid. Thereby, parts other than the location used as the metal wiring part 13 are removed among metal foil.

  Finally, the etching mask is removed using an alkaline stripping solution. As a result, the etching mask is removed from the surface of the metal wiring portion 13.

(Insulating protective film formation process)
After forming the metal wiring part, the insulating protective film 14 is laminated. This lamination is not particularly limited as long as it is a coating means that can uniformly coat the insulating ink. For example, screen printing, spray coater, honmelt coater, bar coater, applicator, blade coater, knife coater, air knife coater, curtain Flow coaters, roll coaters, gravure coaters, offset printing, dip coaters, brush coating, and other ordinary methods can all be used. However, among these, by adjusting the ink viscosity, the screen mesh count (screen hole size), and other printing processing conditions (mainly the speed of plate separation), a desired surface roughness can be applied to the surface of the insulating protective film 14. It is preferable to use screen printing that can easily form an arbitrary diffuse reflection surface 141. In particular, in the case where the insulating protective film 14 has a multilayer structure as described above, it is extremely preferable to form the insulating protective film 14 by a process of repeatedly applying the insulating ink by screen printing. In addition, when forming a white insulating protective film having a multilayer structure in which a light reflecting layer as shown in FIG. 6 is formed on an adhesion layer, white insulating ink is applied in a desired pattern for each layer. It is preferable to use a production method in which coating is performed by a screen printing method.

  In addition, in the case of overcoating by screen printing when the insulating protective film 14 has a multilayer structure, the coating range of the insulating ink for forming the adhesion layer is more than the coating range of the insulating ink for forming the light reflecting layer. Expand to the area close to the outer edge of the LED element 2 (in the range of about 0.1 to 0.2 mm in front of the coating area of the insulating ink forming the light reflecting layer so as not to reach the outer edge of the adhesion layer) It is preferred to print each of these layers. By performing the above-described overcoating in such a manner, a fine leak spread from the coating area of the insulating ink that forms a light reflection layer having a relatively large coating thickness, a very fine plate shift, etc. It can prevent that the area | region for LED element mounting which should be ensured on optical design will be eroded.

<Manufacturing method of LED module>
An LED module manufacturing method in which the LED element substrate 1, the LED element 2, and the reflective material 15 manufactured by the above manufacturing method are integrated to form an LED module will be described.

[LED element mounting process]
The LED element 2 is mounted on the LED element substrate 1 by bonding the LED element 2 to the metal wiring portion 13 by soldering. This soldering joining can be performed by a reflow method or a laser method. In the reflow method, the LED element 2 is mounted on the metal wiring part 13 through solder, and then the LED element substrate 1 is transported into the reflow furnace, and hot air at a predetermined temperature is applied to the metal wiring part 13 in the reflow furnace. In this method, the solder paste is melted by spraying, and the LED element 2 is soldered to the metal wiring portion 13. The laser method is a method of soldering the LED element 2 to the metal wiring portion 13 by locally heating the solder with a laser. Solder bonding of the LED element 2 to the metal wiring portion 13 is preferably performed by laser irradiation from the back surface side of the support substrate 11. Thereby, the ignition of the organic component of the solder by heating and the accompanying damage to the base material can be more reliably suppressed. In this step, the solder portion 17 is formed at the position shown in FIG.

[Reflecting material lamination process]
Reflector 15 in which openings are formed in advance on LED element substrate 1 on which a plurality of LED elements 2 are mounted in a matrix is placed at an appropriate position so that all the openings overlap each LED mounting region. The process to mount is performed. Further, when the adhesive layer 16 is formed on the reflective material 15, the reflective material 15 is placed at the same appropriate position with the adhesive layer 16 facing each component of the LED element substrate 1. The reflective material 15 is temporarily attached to the LED element substrate 1.

  After the reflecting material 15 is placed at an appropriate position on the LED element substrate 1, the pushing film 18 is further placed on the reflecting material 15 as shown in FIG. 9. The pushing film 18 may be, for example, a resin film made of polyethylene terephthalate (PET) or the like and having a pushing opening formed at a position corresponding to the opening of the reflecting material 15.

  After the pressing film 18 is placed, the entire surface of the pressing film 18 is evenly pressed by a roller or the like, so that the resin sheet constituting the reflector 15 is formed at the periphery of the opening in the manner shown in FIG. A part is bent toward the top of the LED element 2 to form the LED element surrounding side wall 151. At this time, the surface on the back side of the reflector 15 is pressure-bonded to the surface of the LED element substrate 1, and at the same time, the inner surface of the LED element surrounding side wall 151 is pressure-bonded to the side surface of the LED element 2. After the LED element surrounding side wall 151 is formed, the pushing film 18 is detached from the LED module 10.

  Here, as shown in FIG. 9, the size relationship between the width S3 of the opening of the film 18 for pushing used in the reflecting material pushing step, the outer width S2 of the LED element 2, and the width S1 of the opening of the reflecting material is as follows. S1 <S2 <S3 is set. The difference between S1 and S2 and the difference between S2 and S3 should be optimized as appropriate according to the thickness, bending stress, tensile elongation, etc. of the resin sheet constituting the reflector, and according to the presence or absence of the adhesive layer 16. That's fine. For example, if a heat-resistant double-sided tape having a thickness of 20 μm or more and 100 μm is laminated on a polypropylene foam film having a thickness of 50 μm or more and 200 μm and this is used as a reflecting material, the outer width S2 of the LED element is S1 (S2-1200) (μm) or more (S2-140) (μm) or less, S3 is (S2 + 140) (μm) or more (S2 + 5000) (μm) in the range, the LED element surrounding sidewall 151 It is possible to form in the mode as shown in FIG.

  In the case where the reflective material 15 does not have the adhesive layer 16, the reflective material 15 is fixed at an appropriate position by a push rivet or the like after the pushing, so that the position and form of the reflective material 15 can be appropriately set. Can be held in.

<LED module lighting inspection method>
As described above, as shown in FIGS. 7 and 8, the LED module 10 is a portion parallel to or approximately parallel to the conduction direction between the pair of conductive plates 131 and 132 in the periphery of the opening of the reflector 15. Since only the LED element-enclosing side wall 151 is formed, the LED module 10 is exposed in the vicinity of the periphery of the opening by a plan view from the light emitting surface side of the LED module 10. Alternatively, in various scenes related to subsequent distribution and sales, the conduction state of the solder portion 17 can be inspected by nondestructive inspection.

<LED display device>
FIG. 10 is a perspective view schematically showing a configuration of an LED display device 100 using the LED module 10 of the present invention. The LED display device 100 includes an LED module 10 and an image display panel 3 such as a liquid crystal display panel. In addition, the LED module 10 in this embodiment includes at least the LED element substrate 1, the LED element 2, and the reflective material 15. A reflective material 15 is formed on the outermost surface of the LED element substrate 1 on the light emitting surface side so as to cover the area excluding the LED element mounting area for the purpose of improving the light emitting ability of the LED module 10.

  In the LED display device 100, in order to radiate the heat radiated from the LED module 10 to the outside more efficiently, the heat dissipation structure 4 made of aluminum or the like is further installed on the back side of the LED element substrate 1. preferable. These members are actually fixedly arranged at appropriate positions inside an external frame (not shown) made of metal or the like to constitute the LED display device 100.

DESCRIPTION OF SYMBOLS 1 LED element substrate 11 Support substrate 12 Adhesive layer 13 Metal wiring part 131,132 Conductive plate 14 Insulating protective film 15 Reflective material 151 LED element surrounding side wall 152 Concave reflection part 153 Cut 16 Adhesive layer 17 Solder part 18 Pushing film 2 LED element 3 Image display panel 4 Heat dissipation structure 10 LED module 100 LED display device

Claims (9)

A substrate for an LED element in which a metal wiring part is formed on the surface of the support substrate;
A plurality of LED elements mounted on the metal wiring part;
A LED module that covers a region excluding the mounting region of the LED element and is laminated on the LED element substrate;
The LED element is mounted via a solder portion on a mounting portion formed of a pair of conductive plates that are part of the metal wiring portion and formed at positions facing each other apart from each other,
The reflective material is made of a flexible resin sheet, and an opening is formed at a position corresponding to the mounting area.
A part of the resin sheet is bent toward the top of the LED element and rises at a portion parallel to or substantially parallel to the conduction direction between the pair of conductive plates in the periphery of the opening. The LED element surrounding side wall is formed, and at least a part of the inner surface including the top of the LED element surrounding side wall is in contact with the side surface of the LED element,
Of the periphery of the opening, the LED element-enclosing side wall is not formed in a portion parallel or substantially parallel to the direction orthogonal to the conduction direction,
In a plan view from the light emitting surface side of the LED module, a solder portion that fixes the LED element to the metal wiring portion in the vicinity of a portion of the periphery of the opening where the LED element surrounding side wall is not formed Is an LED module that is visible.   The LED module according to claim 1, wherein a bending stress based on ASTM-D790 of the resin sheet forming the reflective material is 10 MPa or more and 40 MPa or less.   The adhesive layer is formed in the back surface of the said reflecting material, This reflecting material is affixed on the said board | substrate for LED elements and the said LED element via this adhesive layer. LED module.   The LED element-enclosing side wall rises substantially perpendicularly to the surface of the LED element substrate at the periphery of the opening, and the substantially entire inner surface of the LED element-enclosing side wall is on the side surface of the LED element. The LED module according to claim 1, which is in contact with the LED module.   Of the back surface of the LED element surrounding side wall, only a part of the surface near the top side is in contact with a part near the top side of the side surface of the LED element, and the LED element surrounding side wall extends from the periphery of the opening. The LED module according to any one of claims 1 to 4, wherein the LED module rises in a tapered shape with an opening diameter narrowing toward a top portion of the LED element.   The LED module according to claim 5, wherein the LED element surrounding side wall has a concave curved surface shape that is convex toward the support substrate side.   The LED module according to claim 1, wherein the support substrate is a flexible resin film, whereby the LED element substrate is a flexible substrate.   An LED display device comprising a backlight comprising the LED module according to claim 1. It is the lighting inspection method of the LED module in any one of Claim 1 to 7,
Inspecting the conductive state of the solder part exposed in the vicinity of the periphery of the opening part in a plan view from the light emitting surface side of the LED module without destroying any part of the LED module. A lighting inspection method for an LED module, comprising a step.

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