JP2012014957A - Light-emitting module, and lighting fixture equipped with this - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting module with slow degradation of a luminous flux maintenance factor.SOLUTION: The light-emitting module 21 includes a module substrate 22, a wiring pattern 25 for a cathode, a wiring pattern 26 for an anode, a plurality of semiconductor light-emitting elements 45, bonding wires 47 to 52, and translucent sealing resin 57. The semiconductor light-emitting elements 45 are directly mounted on the module substrate 22, and these light-emitting elements 45 and the wiring patterns 25, 26 are electrically connected to the bonding wires 47 to 52. The sealing resin 57, provided on the module substrate 22 with phosphors mixed in, seals the semiconductor light-emitting elements 45, wiring patterns 25, 26, and the bonding wires 47 to 52, and a light-emitting face 57a is formed on the surface of the sealing resin 57. An occupying rate of an area covered with the sealing resin 57 of the wiring patterns 25, 26 to the light-emitting face 57a is to be 5% or more to 40% or less.

Description

  Embodiments of the present invention relate to a light-emitting module that can be suitably used for, for example, a light source, and a lighting device such as a road lamp that includes the module as a light source.

  As a COB (Chip On Board) type light emitting module, a plurality of semiconductor light emitting elements, for example, chip-shaped LEDs (light emitting diodes) are arranged between a plurality of wiring patterns provided on a module substrate, and these LEDs are connected with bonding wires. A device having a configuration in which a wiring pattern, each LED, and the like are embedded with a sealing resin mixed with a phosphor is known as a prior art.

  When white light emission is obtained with this light emitting module, an LED that emits blue light is generally used, and a yellow phosphor that emits yellow light when excited by blue light is used as the phosphor. Thereby, the surface of the sealing resin functions as a white light emitting surface.

  In a light emitting module having such a light emitting surface, the wiring pattern made of Ag (silver) is because the color of light reflected by the wiring pattern is similar to the color of the light emitting surface. This is preferable in that the light color reflected by the light source is not easily affected and the cost is relatively low.

  By the way, the sealing resin has gas permeability. Therefore, the silver wiring pattern reacts with the sulfur gas in the air that permeates the sealing resin and gradually becomes darker. As the blackening of the wiring pattern progresses, the light reflection performance gradually decreases, so that the light extraction efficiency from the light emitting module decreases. In other words, the luminous flux maintenance factor of the light emitting module decreases. Therefore, it is desired to make the decrease in the luminous flux maintenance factor of the light emitting module as slow as possible.

  At the same time, in a luminaire including a COB light emitting module as a light source, it is recommended that the luminaire be replaced when the light source reaches a specified life even when it can be turned on. Here, the specified life of the light source is the life specified by the manufacturer of the lighting fixture, and the state in which the luminous flux maintenance factor is reduced to, for example, 70% or less based on the luminous flux maintenance factor immediately after production. Pointing. The specified life of such a light source is relatively short due to the blackening phenomenon in a lighting fixture having the above-described light emitting module.

  Then, there is no way for the user to know whether or not the light source comprising the COB type light emitting module has reached the specified life. Therefore, the user may continue to use the lighting fixture even when the luminous flux maintenance factor is reduced to, for example, 70% or less. In this case, there is an inconvenience that the lighting environment is considerably lowered. Therefore, it is preferable that the time until the light source of the luminaire composed of the COB type light emitting module reaches the specified life is as long as possible, and it is desired to realize such.

JP 2009-290244 A

  Embodiments are intended to provide a light-emitting module with a slow decrease in luminous flux maintenance factor, and a luminaire that includes this module as a light source and can increase the time until the light source reaches a specified life. .

  In order to solve the above problems, a light emitting module of an embodiment includes a module substrate, a positive electrode wiring pattern, a negative electrode wiring pattern, a plurality of semiconductor light emitting elements, bonding wires, and a translucent sealing resin. The module substrate is made of white ceramics. A wiring pattern is formed of silver, and these patterns are provided on the module substrate. The semiconductor light emitting elements are mounted directly on the module substrate, and the light emitting elements and the wiring pattern are electrically connected with bonding wires. The sealing resin is mixed with a phosphor, and the sealing resin is provided on the module substrate to seal the semiconductor light emitting element, the wiring pattern, and the bonding wire, and the light emitting surface is formed by the sealing resin. The occupation ratio of the area covered with the sealing resin of the silver wiring pattern with respect to the light emitting surface is 5% or more and 40% or less.

  According to the light emitting module of the embodiment, it is possible to expect an effect that it is possible to moderate the decrease in the luminous flux maintenance factor.

It is a perspective view which shows the road light provided with the light emitting module which concerns on Example 1. FIG. It is a perspective view which expands and shows the lamp of the road light of FIG. It is a perspective view which shows the light source device with which the lamp of FIG. 2 is provided. It is a schematic front view which shows the light source device of FIG. It is a front view which shows the light emitting module with which the light source device of FIG. 3 is provided. It is a front view which shows the light emitting module of FIG. 5 in the state which passed through the 1st manufacturing process. It is a front view which shows the light emitting module of FIG. 5 in the state which passed through the 2nd manufacturing process. It is a front view which shows the light emitting module of FIG. 5 in the state which passed through the 3rd manufacturing process. It is a front view which shows the light emitting module of FIG. 5 in the state which passed through the 4th manufacturing process. FIG. 5 is a cross-sectional view taken along line F10-F10 in FIG. It is a graph which shows the relationship between the wiring silver occupation rate and luminous flux maintenance factor in the light emitting module of FIG.

  The light emitting module of Embodiment 1 includes a module substrate made of white ceramics; a silver wiring pattern provided on the module substrate with a positive electrode; and a silver wiring provided on the module substrate with a negative electrode A plurality of semiconductor light emitting elements mounted between the wiring patterns and directly mounted on the module substrate; bonding wires provided by electrically connecting the semiconductor light emitting elements and the wiring patterns; And a light-transmitting sealing resin which is provided on the module substrate by sealing the semiconductor light emitting element, the wiring pattern, and the bonding wire, and forms a light emitting surface. The occupation ratio of the area covered with the sealing resin of the wiring pattern made of silver to the light emitting surface is 5% or more and 40% or less. It is a symptom.

  In the first embodiment, the white ceramic forming the module substrate is any one selected from aluminum oxide (alumina), aluminum nitride, boron nitride, silicon nitride, magnesium oxide, forsterite, steatite, and low-temperature sintered ceramics. Alternatively, these composite materials can be used, and in particular, alumina that is inexpensive, has high light reflectance, and is easy to process can be suitably used. In the first embodiment, that the wiring pattern is made of silver includes a pure silver wiring pattern and a wiring pattern formed mainly of silver.

  In the first embodiment, for example, various light-emitting elements in which a compound semiconductor is provided on an element substrate can be used as the semiconductor light-emitting element, and in particular, a blue LED made of a bare chip that emits blue light is used. Although it is preferable, it is also possible to use a semiconductor light emitting element that emits ultraviolet light or green light.

  In the first embodiment, the bonding wire may be a fine metal wire, such as a gold wire, an aluminum wire, a copper wire, and a platinum wire, but in particular, moisture resistance, environment resistance, adhesion, electrical conductivity, It is preferable to use a gold wire having good thermal conductivity and elongation as a bonding wire.

  In Embodiment 1, a translucent resin material such as an epoxy resin, a urea resin, or a silicone resin can be used as the sealing resin. In the first embodiment, the phosphor mixed in the sealing resin is excited by the light emitted from the semiconductor light emitting element, emits light of a color different from this light, and the color of the emitted light For example, in order to obtain white illumination light under the condition that a blue LED is used for the semiconductor light-emitting element, light of a color necessary for illumination is formed by a combination with the emission color of the semiconductor light-emitting element. In order to obtain white illumination light under the condition that an LED emitting ultraviolet light is used for the semiconductor light emitting element, red, blue and yellow phosphors may be used. In the first embodiment, the light emitting surface refers to a surface from which illumination light is emitted toward an illumination target or the like, and specifically is a surface of a sealing resin.

  In the first embodiment, since the module substrate is made of white ceramics, the light incident on the component mounting surface consisting of the ground surface of the module substrate from the semiconductor light emitting element and the phosphor directly mounted on the substrate is It can be reflected in the light extraction direction on the component mounting surface. The light reflection performance is maintained constant regardless of the elapsed time from the start of use of the light emitting module. On the other hand, the silver wiring pattern sealed with the sealing resin is gradually darkened, and its light reflection performance gradually decreases. However, since the area occupation ratio with respect to the light emitting surface of the portion sealed with the sealing resin of the wiring pattern is set to 40% or less, the deterioration of the light reflecting performance with the progress of the blackening of the wiring pattern causes the light reflection of the entire light emitting module. The effect on performance can be limited to a small level. Along with this, it is possible to slow down the decrease in luminous flux maintenance factor. In addition, since the area occupation ratio of the portion of the wiring pattern sealed with the sealing resin with respect to the light emitting surface is set to 5% or more, there is no problem in electrically connecting the semiconductor light emitting element with the bonding wire. Therefore, it is possible to prevent manufacturing feasibility from becoming difficult.

  The light emitting module of Embodiment 2 is characterized in that the average reflectance of the module substrate with respect to visible light is 85% or more and 99% or less in Embodiment 1.

  In the second embodiment, since the light reflection performance of the white module substrate is higher than that in the first embodiment, the light extraction efficiency can be increased, and the decrease in the luminous flux maintenance factor can be slowed under this condition. .

  The lighting fixture of Embodiment 3 includes a light source device having the light emitting module of Embodiment 1 or 2 as a light source; and a fixture body to which the light source device is attached. This Embodiment 3 can be applied to any type of lighting fixture without being restricted by the road lamp described in Example 1 described later.

  In the luminaire of Embodiment 3, the light source device has the light emitting module described in Embodiment 1 or 2 as the light source, and accordingly, the light source is defined in accordance with the slow decrease in the luminous flux maintenance factor of the light emitting module. It is possible to lengthen the time until reaching the lifetime.

  Hereinafter, the lighting fixture provided with the light emitting module of Example 1, for example, a road lamp, is demonstrated in detail with reference to FIGS. Note that FIG. 10 is drawn with the protective layer described later omitted for convenience of explanation.

  Reference numeral 1 in FIG. 1 indicates a road lamp installed for road illumination. The road lamp 1 is formed by attaching a lamp 3 to the upper end of a column 2.

  The column 2 is erected on the side of the road, and its upper part is bent so as to cover the road. As shown in FIG. 2, the lamp 3 includes a fixture body connected to the column 2 as shown in FIG. 2, for example, a lamp body 4, a translucent plate 5 attached to the lamp body 4 by closing the lower surface opening of the lamp body 4 facing the road, At least one light source device 6 accommodated in the lamp body 4 is formed to face the light transmitting plate 5. The lamp body 4 is formed by combining a metal, for example, a plurality of aluminum die cast products. The translucent plate 5 is made of tempered glass.

  As shown in FIGS. 3 and 4, the light source device 6 has a plurality of heat radiation fins 14 protruding from the back surface of the device base 11, and a reflector 15 and a light emitting module 21 as a light source are attached to the front surface of the device base 11. This is a unitized configuration.

  The device base 11 is made of a metal, for example, aluminum die-cast, and is formed in a square shape. The apparatus base 11 has a module installation portion 12 (see FIGS. 4 and 10) formed of a square recess opened on the front surface thereof. The bottom surface 12a of the module installation part 12 is flat, and the four side surfaces 12b defining the module installation part 12 are continuous at right angles to each other. The heat radiating fins 14 are formed integrally with the apparatus base 11.

  The reflector 15 is formed by combining the first reflecting plate 15a to the fourth reflecting plate 15d in a trumpet shape. The first reflecting plate 15a and the second reflecting plate 15b are flat mirrors having a flat configuration, and are provided in parallel to each other. The third reflecting plate 15c and the fourth reflecting plate 15d connected to the first reflecting plate 15a and the second reflecting plate 15b are curved mirrors having a curved configuration so that the distance between them gradually increases. Is provided.

  The light source device 6 is fixed in the lamp body 4 with the exit opening of the reflector 15 facing the translucent plate 5. In this fixed state, a part of the device base 11, for example, a peripheral portion is connected to the inner surface of the lamp body 4 so as to be able to conduct heat. This thermal connection can be realized by bringing the peripheral portion into direct contact with the inner surface of the lamp body 4, and the peripheral portion is connected to the inner surface of the lamp body 4 through a heat conductive member such as a metal or a heat pipe having high heat dissipation. It can be realized by connecting to. As a result, the heat generated by the light source device 6 can be released to the outside using the metal lamp body 4 as a heat radiating surface.

  Next, the light emitting module 21 will be described. As shown in FIG. 5 and the like, the light emitting module 21 includes a module substrate 22, a first wiring pattern, for example, a wiring pattern 25 that forms a positive electrode, a second wiring pattern, for example, a wiring pattern 26 that forms a negative electrode, an alignment mark 35, Protective layer 37, second protective layer 38, a plurality of identity marks, for example, a first identity mark 41 to a fourth identity mark 44, a plurality of semiconductor light emitting elements 45, and bonding wires 47 to 52. A frame 55, a sealing resin 57, a connector 61, a capacitor 65, and the like.

The module substrate 22 is formed of white ceramic, for example, white AL ₂ O ₃ (aluminum oxide). The module substrate 22 may be formed of only aluminum oxide, but may contain aluminum oxide as a main component and other ceramics or the like mixed therein. The content is preferably 70% or more.

  The average reflectance of the white module substrate 22 with respect to the visible light region is 80% or more, and more preferably 85% or more and 99% or less. Therefore, the module substrate 22 has similar light for blue light having a specific emission wavelength of 440 nm to 460 nm emitted by a blue LED described later and yellow light having a specific emission wavelength of 470 nm to 490 nm emitted by a phosphor described later. Exhibits reflective performance.

  As shown in FIG. 4, the module substrate 22 has a substantially rectangular shape that is slightly smaller than the module installation portion 12. As shown in FIG. 5, the four corners of the module substrate 22 are rounded. The thickness of the module substrate 22 is thinner than the depth of the module installation part 12 as shown in FIG. Both surfaces of the module substrate 22 are flat surfaces made parallel to each other, and one of the surfaces is used as a component mounting surface 22a.

  The positive electrode wiring pattern 25 and the negative electrode wiring pattern 26 are provided on the component mounting surface 22a.

  Specifically, as shown in FIG. 6 and the like, the positive electrode wiring pattern 25 has a positive electrode pattern base portion 25a and a wire connection portion 25b. The wire connecting portion 25b is formed to extend straight. The positive electrode pattern base portion 25a and the wire connection portion 25b are substantially parallel to each other and are integrally continuous via an oblique pattern portion. A first positive electrode pad portion 25c and a second positive electrode pad portion 25d are integrally projected on the positive electrode pattern base portion 25a.

  The negative electrode wiring pattern 26 includes a negative electrode pattern base portion 26a, a first wire connection portion 26b, an intermediate pattern portion 26c, and a second wire connection portion 26d. This wiring pattern 26 is provided so as to surround the wiring pattern 25 for the positive electrode.

  That is, the negative electrode pattern base 26 a is provided adjacent to the positive electrode pattern base 25 a of the wiring pattern 25 with a predetermined insulation distance A therebetween. A first negative electrode pad portion 26e provided side by side with the first positive electrode pad portion 25c is integrally projected from the negative electrode pattern base portion 26a. The first wire connecting portion 26b is integrally continuous so as to be bent about 90 ° with respect to the negative electrode pattern base portion 26a. The first wire connection portion 26b is provided substantially parallel to the wire connection portion 25b by forming a first element disposition space S1 between the wire connection portion 25b of the wiring pattern 25. Here, “substantially parallel” includes a parallel form as shown in FIG. 6, a slightly inclined form with respect to the wire connecting portion 25 b, a slightly curved form, and the like.

  The intermediate pattern portion 26c is provided integrally and continuously so as to be bent about 90 ° with respect to the first wire connecting portion 26b. The leading end of the wire connecting portion 25b (the end opposite to the positive electrode pattern base portion 25a) is adjacent to the intermediate portion in the longitudinal direction of the intermediate pattern portion 26c. Both end portions of the intermediate pattern portion 26c are inclined in opposite directions, and the intermediate pattern portion 26c is formed in a substantially curved shape. Thereby, the intermediate portion in the longitudinal direction of the intermediate pattern portion 26c is kept away from the tip of the wire connection portion 25b.

  The second wire connecting portion 26d is provided integrally and continuously so as to be bent by approximately 90 ° with respect to the intermediate pattern portion 26c. Thereby, the second wire connecting portion 26d is provided substantially parallel to the wire connecting portion 25b by forming the second element disposition space S2 between the wire connecting portion 25b of the wiring pattern 25 and the second element connecting space 25b. Here, “substantially parallel” includes a parallel form as shown in FIG. 6, a slightly inclined form with respect to the wire connecting portion 25b, a slightly curved form, and the like.

  Therefore, the negative electrode wiring pattern 26 is provided so as to surround the positive electrode wiring pattern 25 from three directions. The first wire connecting portion 26b and the second wire of the negative wiring pattern 26 are bordered by the wire connecting portion 25b of the wiring pattern 25 disposed in the center of the region surrounded by the negative wiring pattern 26. The connecting portions 26d are arranged symmetrically.

  A second negative electrode pad portion 26f is provided corresponding to the second positive electrode pad portion 25d continuously and integrally at the tip of the second wire connection portion 26d. The second negative electrode pad portion 26f and the second positive electrode pad portion 25d are spaced apart from each other, and an intermediate pad 27 is formed on the component mounting surface 22a so as to be positioned therebetween.

  The wiring pattern 25 may be used for the negative electrode and the wiring pattern 26 may be used for the positive electrode. In this case, “positive electrode” or “positive electrode” in the above description is read as “for negative electrode” or “negative electrode” and “negative electrode” “For” or “negative electrode” may be read as “for positive electrode” or “positive electrode”.

  Further, lighting inspection pads 28 and 29 for lighting confirmation test, temperature inspection pad 31 for temperature measurement, and mounting pad 33 for component fixing are provided on the component mounting surface 22a.

  That is, the lighting inspection pad 28 is connected to the wiring pattern 25 for the positive electrode. Specifically, the lighting inspection pad 28 is provided through a pattern portion 28a branched from the positive electrode pattern base portion 25a and integrally protruding. Similarly, the lighting inspection pad 29 is connected to the negative wiring pattern 26. Specifically, a lighting inspection pad 29 is provided through a pattern portion 29a that branches from the negative electrode pattern base portion 26a and protrudes integrally.

  The temperature inspection pad 31 is provided in the vicinity of the lighting inspection pad 29 and the negative electrode wiring pattern 26 independently without having an electrical connection relationship therewith. A thermocouple is connected to the temperature inspection pad 31 so that the temperature of the light emitting module 22 can be measured.

  A pair of mounting pads 33 are formed, and these mounting pads 33 are provided between the lighting inspection pads 28 and 29.

  The alignment mark 35 includes a wire connecting portion 25b, a first element disposing space S1 and a second element disposing space S2 on both sides thereof, a first wire connecting portion 26b adjacent to the first element disposing space S1, and a second A plurality of second wire connecting portions 26d adjacent to the element arrangement space S2 are provided on both sides of the second wire connecting portion 26d. Therefore, a part of the alignment mark 35 is provided in a line along the longitudinal direction of the first wire connection part 26b at a predetermined interval, and the other alignment marks 35 are similarly connected to the second wire at a predetermined interval. It is provided in a line along the longitudinal direction of the portion 26d.

  The wiring patterns 25 and 26, the intermediate pad 27, the lighting inspection pads 28 and 29, the mounting pad 33, and the alignment mark 35 are all made of silver, for example, silver as a main component, and these are mounted by screen printing or the like. It is provided by printing on the surface 22a (first manufacturing process). In addition, it can replace with printing and can also provide by plating.

  The first protective layer 37 and the second protective layer 38 are made of an electrically insulating material, and are printed on the component mounting surface 22a by screen printing, and the sealing resin 57 described later in the silver printed matter. In order to prevent the deterioration of the part that is not sealed by this, this part is mainly covered (second manufacturing process).

  That is, as shown in FIG. 7, the first protective layer 37 is applied to the positive electrode pattern base 25a except for the first positive electrode pad portion 25c and the second positive electrode pad portion 25d, and the first negative electrode Except for the pad portion 26e, the negative electrode pattern base portion 26a is attached. Further, the first protective layer 37 is also applied to a gap portion that secures an insulation distance A between the positive electrode pattern base portion 25a and the negative electrode pattern base portion 26a, and is also applied to the pattern portions 28a and 29a. ing. In addition, the first protective layer 37 is attached to the end of the second wire connecting portion 26d on the second negative electrode pad portion 26f side except for the second negative electrode pad portion 26f, and the intermediate layer The pad 27 is also attached to the intermediate pad 27 except for both ends of the pad 27. The second protective layer 38 is attached to substantially the entire intermediate pattern portion 26c.

  The first identity mark 41 to the fourth identity mark 44 are provided on the component mounting surface 22a in a color different from that of the module substrate 22 by screen printing or the like (third manufacturing process). Further, by this printing or the like, polarity indications of “+” and “−” are also provided on the component mounting surface 22a. The first identity mark 41 to the fourth identity mark 44 and the like are preferably printed and provided simultaneously with the first protective layer 37 and the second protective layer 38. The first identity mark 41 is a company name indicating the manufacturer, the second identity mark 42 is a product name, the third identity mark 43 is a product number, and the fourth identity mark 44 is It is a two-dimensional barcode (QR code) showing information about the light emitting module 21.

  For each of the plurality of semiconductor light emitting elements 45, a light emitting element that generates heat in a light emitting state, for example, a chip-like blue LED that emits blue light is used. These semiconductor light emitting elements 45 are preferably formed of a bare chip having a configuration in which a semiconductor light emitting layer is provided on a light-transmitting element substrate made of sapphire glass and a pair of element electrodes is provided on the light emitting layer.

  Since light emission of an LED is realized by passing a forward current through a pn junction of a semiconductor, the LED is a solid element that directly converts electric energy into light. A semiconductor light emitting element that emits light based on such a light emission principle has an energy saving effect as compared with an incandescent bulb that inclines a filament to a high temperature by energization and emits visible light by its thermal radiation.

  Half of the semiconductor light emitting elements 45 are directly mounted on the module substrate 22 in the first element disposition space S1. This mounting is realized by bonding the element substrate to the component mounting surface 22a using a transparent die bond material, and the plurality of semiconductor light emitting elements 45 mounted in the first element disposition space S1 are aligned vertically and horizontally. Arranged in a matrix. Similarly, the remaining semiconductor light emitting elements 45 are mounted directly on the module substrate 22 in the second element arrangement space S2. This mounting is also realized by adhering the element substrate to the component mounting surface 22a using a transparent die bond material, and the plurality of semiconductor light emitting elements 45 mounted in the second element arrangement space S2 are also aligned vertically and horizontally. Arranged in a matrix.

  The plurality of semiconductor light emitting elements 45 disposed in the first element disposition space S1 and the plurality of semiconductor light emitting elements 45 disposed in the second element disposition space S2 are provided symmetrically with respect to the wire connection portion 25b. It has been.

  The semiconductor light emitting elements 45 arranged in a line in the direction in which the wire connection part 25 b of the wiring pattern 25 and the first wire connection part 26 b of the wiring pattern 26 are arranged are connected in series by a bonding wire 47. The semiconductor light emitting elements 45 arranged at one end of the element rows connected in series in this way are connected to the wire connecting portion 25b by the bonding wires 48. At the same time, the semiconductor light emitting element 45 disposed at the other end of the element row is connected to the first wire connecting portion 26b by a bonding wire 49.

  Similarly, the semiconductor light emitting elements 45 arranged in a row in the direction in which the wire connection portion 25 b of the wiring pattern 25 and the second wire connection portion 26 d of the wiring pattern 26 are arranged are connected in series by a bonding wire 50. . The semiconductor light emitting element 45 arranged at one end of the element rows thus connected in series is connected to the wire connecting portion 25b by the bonding wire 51. At the same time, the semiconductor light emitting element 45 disposed at the other end of the element row is connected to the second wire connecting portion 26d by the bonding wire 52 (fourth manufacturing process). The bonding wires 47 to 52 are all made of fine metal wires, preferably gold wires, and are provided by wire bonding.

  By electrically connecting a plurality of semiconductor light emitting elements 45 mounted on the module substrate 22 as described above, a COB (Chip On Board) type light emitting module 21 is configured. Due to the electrical connection, the plurality of semiconductor light emitting elements 45 provided in the element disposition spaces S1 and S2 are electrically connected to, for example, 12 element rows formed by connecting 7 semiconductor light emitting elements 45 in series. Is an array connected in parallel.

  The alignment marks 35 are respectively disposed on the extended lines of the element rows in series. Then, with reference to the left and right (in the drawing) alignment marks 35 positioned on the extension line, the semiconductor light emitting element 45 is mounted by a mounting machine on a straight line passing therethrough.

  As shown in FIG. 9, the frame 55 has, for example, a square ring shape, and each of the wire connecting portions 25b, 26b, and 26d, the plurality of semiconductor light emitting elements 45, and the bonding wires 47 to 52 are housed inside the frame. Mounted on the surface 22a. The frame 55 is preferably made of a white synthetic resin. The frame 55 is attached to part of the first protective layer 37 and part of the second protective layer 38.

  The sealing resin 57 is filled in the frame 55 and seals the wire connecting portions 25b, 26b, and 26d, the plurality of semiconductor light emitting elements 45, and the bonding wires 47 to 52 in an embedded state. Are provided on the module substrate 22 (fifth manufacturing step). The sealing resin 57 is made of a transparent silicone resin or the like mixed with a phosphor (not shown), and is translucent and gas permeable. A yellow phosphor that emits yellow light when excited by blue light emitted from the semiconductor light emitting element 45 is used as the phosphor.

  White light is formed by mixing the blue light and yellow light having a complementary color to the blue light, and the white light is emitted from the surface of the sealing resin 57 in the light use direction. Therefore, the light emitting surface 57 a of the light emitting module 21 is formed by the surface of the sealing resin 57, that is, the light emitting surface. The size of the light emitting surface 57 a is defined by the frame 55.

  When the area of the silver portion covered with the sealing resin 57 is C and the area of the light emitting surface 57a is D, the occupation ratio of the area C to the area D is 5% or more and 40% or less, preferably 15%. It is set in the range of 25% or less. The portions covered with the sealing resin 57 of the wiring patterns 25 and 26 are the wire connection portions 25b, 26b, and 26d. The area of the reflective region covered with the sealing resin 57 is defined by a frame 55, and the size is 13 mm in the vertical direction of the frame 55 and 17.5 mm in the horizontal direction of the frame 55 in FIG. is there.

  Alternatively, the sealing resin 57 may be provided by providing a mold member corresponding to the frame 55 and providing the sealing resin 57 therein, and then removing the mold member from the module substrate 22. In this case, the portion of the wiring patterns 25 and 26 that protrudes from the sealing resin 57 is preferably previously deposited with the first protective layer 37 or the second protective layer 38.

  As shown in FIG. 5, one connector 61 and two capacitors 65 made of surface-mounted components are mounted on the component mounting surface 22a (sixth manufacturing process).

  That is, the connector 61 has a two-pin type configuration having a first terminal pin 61a and a second terminal pin 61b protruding from one side surface thereof. The connector 61 is soldered to the mounting pad 33, thereby being disposed between the lighting inspection pads 28 and 29. At the same time, the first terminal pin 61a is attached to the first positive electrode pad portion 25c, and the second terminal pin 61b is attached to the first negative electrode pad portion 26e. The connector 61 is connected with an insulation coated electric wire for direct current power supply connected to a power supply device (not shown). As a result, power can be supplied to the light emitting module 21 via the connector 61.

  One of the two capacitors 65 is soldered to one end portion of the second positive electrode pad portion 25d and the intermediate pad 27 of the wiring pattern 25, and is disposed over these. Similarly, the other of the two capacitors 65 is soldered to the second negative electrode pad portion 26 f of the wiring pattern 26 and the other end portion of the intermediate pad 27, and is disposed over these. In a normal lighting state in which direct current is supplied to each semiconductor light emitting element 45, no current flows through the capacitor 65. However, when an alternating current flows due to noise superposition, a current flows through the capacitor 65 and the wiring patterns 25 and 26 are short-circuited, whereby an alternating current is supplied to each semiconductor light emitting element 45. It is preventing.

  As shown in FIG. 10, the light emitting module 21 having the above-described configuration is attached to the apparatus base 11 by bringing the back surface of the module substrate 22, that is, the surface opposite to the component mounting surface 22 a into close contact with the bottom surface 12 a of the module installation portion 12. It is supported. Thereby, the light emitting module 21 is supported by the apparatus base 11 so that heat can be radiated from the module substrate 22 to the module installation unit 12. In a state where the light emitting module 21 supported in this way is attached to the lamp body 3, the light emitting surface 57 a faces the light transmitting plate 5.

  In order to support the module, a plurality of, for example, two metal pressing plates 71 are screwed to the apparatus base 11 as shown in FIGS. The front ends of these presser plates 71 are opposed to the peripheral portion of the module substrate 22, and a metal spring 72 that presses the peripheral portion of the module substrate 22 is attached to the front end portion. The state in which the back surface of the module substrate 22 is in close contact with the bottom surface 12a is maintained by the spring force of the springs 72. Such holding can prevent the module substrate 22 from being damaged even if stress is applied to the ceramic module substrate 22 in the heat cycle caused by the temperature increase accompanying the lighting of the light emitting module 21 and the temperature decrease accompanying the extinction of light. It is configured.

  When power is supplied to the road light 1 having the above-described configuration, the plurality of semiconductor light emitting elements 45 included in the light emitting module 21 emit light at the same time, so that white light emitted from the light emitting surface 57a is transmitted through the light transmitting plate 5. Directly transmitted or reflected by the inner surface of the reflector 15 and then transmitted through the light-transmitting plate 5 to illuminate a road having illumination symmetry. With this illumination, the light reflected by the first reflecting plate 15a and the second reflecting plate 15b made of a plane mirror is irradiated mainly in the longitudinal direction of the road without substantially spreading. At the same time, the light reflected by the third reflecting plate 15c and the fourth reflecting plate 15d made of a curved mirror is mainly irradiated in the width direction of the road with the irradiation angle with respect to the width direction of the road being controlled.

  In such illumination, light emitted from the light emitting surface 57a is light that has directly transmitted through the sealing resin 57 from the semiconductor light emitting element 45, or light that has been emitted from the phosphor in the sealing resin 57 and directly transmitted through the sealing resin 57. In addition, the light is incident on the component mounting surface 22a through the element substrate and the die bonding material of the semiconductor light emitting device 45, reflected by the component mounting surface 22a, and transmitted through the sealing resin 57, and emitted from the phosphor. Light that is incident on the component mounting surface 22a through the sealing resin 57, reflected by the component mounting surface 22a, and transmitted through the sealing resin 57 again is included.

  As described above, the light emitting module 21 has the module mounting surface 22a having the component mounting surface 22a made of white ceramics and has an average reflectance of 80% or more. Therefore, the light incident on the component mounting surface 22a, that is, The blue light emitted from the blue LED forming the semiconductor light emitting device 45 and the yellow light emitted from the phosphor having the emission wavelength of 470 nm to 490 nm are efficiently emitted in the road direction, in other words, the light extraction direction. Can be reflected. In particular, when the average reflectance of the component mounting surface 22a of the module substrate 22 is 85% or more and 99% or less, the light incident on the component mounting surface 22a is more efficiently reflected in the light extraction direction. Can do.

  Since the module substrate 22 having the component mounting surface 22a that reflects light is made of white ceramics and uses the ground surface as the component mounting surface 22a, the reflection performance of the module substrate 22 is as follows. Regardless of the elapsed time from the start of use of the light emitting module 21, it is maintained constant.

  Further, the reflection of light on the module substrate 22 side is not limited to the component mounting surface 22a, but the wire connection portion 25b of the silver wiring pattern 25 sealed with the sealing resin 57 and the first of the silver wiring pattern 26. The wire connection portion 26b and the second wire connection portion 26d are also performed. However, the wire connection portions 25b, 26b, and 26d become darker as the elapsed time from when the road light 1 is installed becomes longer. The light reflection performance gradually decreases.

  However, in the light emitting module 21 configured as described above, the area occupation ratio of the silver wire connection portions 25b, 26b, and 26d with respect to the area of the light emitting surface 57a is defined to be 40% or less. In other words, the reflection area on the component mounting surface 22a is ensured to exceed 60% of the area of the light emitting surface 57a. In this case, the positive electrode pattern base 25a of the silver wiring pattern 25 and the intermediate pattern portion 26c of the silver wiring pattern 26 are not sealed with the sealing resin 57 and are outside the light emitting surface 57a. It is preferable for making the area occupancy 40% or less.

  By defining the area occupancy rate, it is possible to limit the influence of the decrease in the light reflection performance accompanying the progress of the blackening of the wire connection portions 25b, 26b, and 26d on the light reflection performance of the entire light emitting module 21. Therefore, according to the light emitting module of Example 1, it is possible to moderate the decrease in the luminous flux maintenance factor of the light emitting module 21. In other words, the deterioration of the light reflection performance in the reflection region covered with the light emitting surface 57a is slow. As a result, the light extraction efficiency is maintained at a high level, so that the energy saving effect can be promoted.

  As the decrease in the luminous flux maintenance factor is slow as described above, it is possible to provide the road lamp 1 that takes a long time for the light emitting module 21 as the light source to reach a specified life, for example, the luminous flux maintenance factor reaches 70%. Is possible. In other words, when the area occupancy of the sealed silver portion with respect to the light emitting surface 57a is 40% or less, even when the road lamp (lighting fixture) 1 is used beyond the recommended life, Regardless of the blackening of the portion, the luminous flux maintenance factor of the light emitting module 21 can be maintained at 70% or more. Note that the recommended life as a guide for replacement of the road lamp 1 is defined when the luminous flux maintenance factor reaches 70%.

  FIG. 11 is a graph showing the relationship between the luminous flux maintenance factor and the wiring silver area occupancy rate in the reflection region, based on the results of tests conducted by the inventors using the light emitting module 21 having the above configuration. As a test result, when the wiring silver area occupation ratio is 18%, the luminous flux maintenance ratio is 86%, when the wiring silver area occupation ratio is 25%, the luminous flux maintenance ratio is 80%, and when the wiring silver area occupation ratio is 35%, the luminous flux maintenance ratio is high. It was confirmed that the luminous flux maintenance factor was 69% when 73% and the wiring silver area occupation ratio were 40%. From this result, it is understood that the luminous flux maintenance factor can be increased to 70% or more by setting the wiring silver area occupation ratio to 40% or less. In particular, it is preferable that the wiring silver area occupancy is 15% to 25% because the luminous flux maintenance factor can be 80% or more.

  When the area occupancy ratio of the sealed silver portion to the light emitting surface 57a (that is, the wiring silver area occupancy ratio) exceeds 40%, the light of the entire light emitting module 21 due to the progress of blackening of the silver portion. The influence on the reflection performance becomes too great, and accordingly, the decrease in the luminous flux maintenance factor of the light emitting module 21 is accelerated, and the time required until the luminous flux maintenance factor reaches 70% is shortened. Therefore, the problem of the present embodiment cannot be solved, which is inappropriate.

  Further, the area occupancy ratio of the wire connection portions 25b, 26b, 26d of the wiring patterns 25, 26 sealed with the sealing resin 57 to the light emitting surface 57a (that is, the wiring silver area occupancy ratio) is 5% or more. Thereby, the width of the wire connecting portions 25b, 26b, and 26d can be formed to be wide to some extent so as not to hinder the wire bonding of the bonding wires 48, 49, 51, and 52 to these portions. Accordingly, it is possible to prevent manufacturing problems. In particular, when the wiring silver area occupancy is less than 15%, the wire bonding area when the semiconductor light emitting element 45 made of the LED chip is mounted in the reflection area having the above-described area is eliminated. The feasibility of manufacturing 22 becomes extremely difficult. However, this difficulty in mounting can be solved by setting the wiring silver area occupation ratio to 15% or more. Therefore, the light emitting module 22 having the wiring silver area occupation ratio of 15% or more and 25% or less is preferable in that there is no difficulty in manufacturing and the luminous flux maintenance factor can be secured at 80% or more.

  DESCRIPTION OF SYMBOLS 1 ... Road light (lighting fixture), 4 ... Lamp body (equipment main body), 6 ... Light source device, 21 ... Light emitting module, 22 ... Module board | substrate, 25 ... Wiring pattern, 26 ... Wiring pattern, 45 ... Semiconductor light-emitting device, 47 ˜52: bonding wire, 57: sealing resin, 57a: light emitting surface

Claims (3)

A module substrate made of white ceramics;
A silver wiring pattern provided on the module substrate as a positive electrode;
A silver wiring pattern provided on the module substrate as a negative electrode;
A plurality of semiconductor light-emitting elements located between the wiring patterns and mounted directly on the module substrate;
A bonding wire provided by electrically connecting the semiconductor light emitting element and the wiring pattern;
A translucent sealing resin which is mixed with a phosphor and seals the semiconductor light emitting element, the wiring pattern, and the bonding wire and is provided on the module substrate to form a light emitting surface;
Comprising
An occupancy ratio of the area covered with the sealing resin of the wiring pattern made of silver to the light emitting surface is 5% or more and 40% or less.   2. The light emitting module according to claim 1, wherein an average reflectance of the module substrate with respect to visible light is 85% or more and 99% or less. A light source device having the light emitting module according to claim 1 as a light source;
An instrument body to which the light source device is attached;
The lighting fixture characterized by comprising.

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