JP2015195299A - Light emitting diode module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting diode module, improving light extraction efficiency while suppressing the deterioration of a heat dissipation effect and durability performance.SOLUTION: A light-emitting diode module 1 includes a plurality of light-emitting diode elements 2 on a copper substrate 3. A reflector plate 5 is attached in such a manner that the whole surface is closely adhered to a predetermined area α on the copper substrate 3. The light-emitting diode elements 2 are mounted on the reflector plate 5 in an electrical insulation state. A titanium oxide thin film 7 is formed by vacuum deposition on the whole surface of a side face of the reflector plate 5 on which the plurality of light-emitting diode elements 2 are secured. The plurality of light-emitting diode elements 2 are encapsulated on the copper substrate 3 along with the reflector plate 5, by a light transmissive resin which includes a fluorescent material.

Description

  The present invention relates to a light emitting diode module in which a plurality of light emitting diode elements are arranged close to each other so as to be integrated on a single substrate. In particular, the present invention relates to a light emitting diode module suitable for a light source of a light emitting diode type lighting apparatus having a relatively large output power and a large light amount.

  In recent years, with the progress of light emitting diode (LED) technology, light emitting diodes have come to be used as light sources for illumination that require higher illuminance. In the present invention, the substantial brightness of light on a plane irradiated on an object is referred to as illuminance. Since the degree of brightness is influenced by human sensation, the illuminance is expressed by the amount of the total luminous flux incident per unit area in order to objectively and quantitatively indicate the brightness as necessary.

  Strictly speaking, there is no white light emitting diode element, so that white light can be obtained by combining two or three color light emitting diode elements, or by combining yellow light emitting diode elements with blue light emitting diode elements. Yes. However, the light emitting diode element alone does not have a sufficient amount of light that can be used as a light source for illumination.

  Therefore, when a light emitting diode is used as a light source for illumination, a required amount of light is obtained by a plurality of light emitting diode elements. However, the light emitted from the light emitting diode has directivity, and the amount of light that can be obtained with the same amount of current varies among the individual light emitting diode elements.

  If adjacent light emitting diode elements are too far apart, even if the supplied current is increased to increase the output power of the light source, the light source is not organized and it is difficult to experience the brightness required for illumination. In order to form a light source that obtains a required illuminance with a plurality of light emitting diode elements, the structure of the light emitting diode elements is more advantageous than the shell type.

  In a chip-type light-emitting diode type lighting fixture, for example, a light-emitting diode element is mounted on a printed wiring board or a metal substrate having an insulating layer by die bonding, and the light-emitting diode element including a phosphor, a translucent portion, or a reflecting member is mounted. It is packaged and attached to the body of the luminaire.

  In particular, in the present invention, a plurality of light-emitting diode elements are arranged close to each other so as to be integrated on a single substrate, and the light-transmitting resin enclosing the plurality of light-emitting diode elements is included in the light-transmitting resin. A unit of a light source integrated with a phosphor, wiring, and terminals is called a light emitting diode module. The light emitting diode module may include a circuit element such as a switching element or a resistance element, a heat radiating member, or a reflecting member.

  Since the light emitting diode is a semiconductor, it generates heat. If the light emitting diode is left standing in a high temperature environment where the temperature exceeds approximately 80 ° C., the semiconductor is damaged. In particular, in the case of a module structure, when the temperature of the light source becomes high, a large number of light emitting diode elements are damaged all at once, or the wiring is blown or short-circuited. There is a risk of damage.

  In addition, as the temperature of the light emitting diode element increases, the light emission efficiency for converting electrical energy into light decreases rapidly, and the amount of light planned in design cannot be obtained. Increasing the current supplied to the light emitting diode element increases the amount of heat generation. Therefore, in order to obtain a larger amount of light as a light source, it is required to increase the number of light emitting diode elements and not to increase the burden on each light emitting diode element.

  When the number of light emitting diode elements is increased to increase the output power of the entire light source, the amount of heat generated by each light emitting diode element does not change, so the temperature around the light source cannot be lowered. In the light emitting diode module, the adjacent light emitting diode elements are provided close to each other so as not to be separated from each other. Therefore, as the number of light emitting diode elements increases, the heat dissipation effect around the light source decreases and the temperature of the light emitting diode elements increases. It falls into a vicious circle of rising.

  Most light-emitting diode luminaires are provided with an aluminum heat sink having a plurality of heat dissipating fins. By quickly dissipating heat generated from a number of light emitting diode elements to the atmosphere by the heat sink, an increase in the temperature of the light source can be suppressed. Further, by improving the light extraction efficiency with a reflector (reflector), the illuminance is increased without increasing the output power so that the temperature around the light source does not increase as much as possible.

  In lighting fixtures that require relatively high illuminance, more light-emitting diode elements are required, so the density of a plurality of light-emitting diode elements arranged on a single substrate is increased, and the output power is correspondingly increased. large. For example, in the case of a lighting device with a large amount of light that has a relatively large output power, such as a projector installed in an outdoor competition facility, the expected heat dissipation effect may not be obtained when the temperature is high. In a large-intensity lighting fixture installed outdoors, it is considerably difficult to suppress an increase in the temperature of the light source by only natural heat dissipation due to air convection.

  By providing a cooling device that has a power source such as a blower fan and actively cools the light emitting diode element, it can be expected to suppress an increase in the temperature of the light emitting diode element. However, providing a cooling device that requires a power source increases power consumption, lowers the production efficiency of the luminaire, increases production costs, and increases the weight of the luminaire.

  In particular, in the case of a luminaire installed outdoors, the cooling device is also more easily damaged because the cooling device is also exposed to sunlight and wind and snow. If the illumination lamp is continuously turned on in a state where the cooling device fails and the operation is stopped, the temperature of the light source rises rapidly and the light emitting diode module is damaged. For this reason, the burden of work and costs required for maintenance such as inspection, repair, or replacement of parts of the lighting fixtures is further increased.

  For this reason, in order to realize a light-emitting diode type projector with a large amount of light that can provide the required brightness in a remote place that can be used in outdoor competition facilities, It is not sufficient to improve the heat radiation efficiency by such a heat sink, the light extraction efficiency by the reflector, and the light emission efficiency of the light emitting diode element itself.

The basic technical idea of improving the light emission efficiency by improving the light extraction efficiency of the light emitting diode element is to provide a light diffusion layer mixed with fine powder made of a material having a reflection characteristic or a reflection layer that reflects light. Is to provide. A useful material capable of obtaining a high reflectance is called a “light diffusing material”. As a light diffusing material, for example, alumina (aluminum) or titania (titanium oxide) is known. In addition, aluminum or titanium oxide includes a case where the chemical formula is Al ₂ O ₃ and TiO ₂ (titanium dioxide).

  In a light emitting diode element semiconductor package or light emitting diode module, a light reflecting layer is formed on the surface of a substrate to which the light emitting diode element is attached, or a light reflecting film is formed on the inner surface of the side wall of the semiconductor package housing. Has been. Further, a fine powder of a light diffusing material is mixed in a light transmitting part (light transmitting resin). The fine powder mixed in the light transmissive resin may be referred to as a filler.

  Specifically, Patent Document 1 and Patent Document 2 disclose a method of forming a light reflection layer on a substrate to which a light-emitting diode element is attached. Patent Document 3 discloses a method of forming a light reflection coating on the inner surface of the side wall of a semiconductor package. Patent Document 4 discloses a method of mixing an appropriate amount of a light diffusing material into a light transmitting part of a semiconductor package. The method shown in the above patent document is a typical example.

JP 2008-199000 A (paragraph 0006) JP 2008-153669 A (paragraph 0111) Japanese Patent Laying-Open No. 2005-19919 (paragraph 0011) JP 10-215001 A (paragraph 0028)

  Providing a light reflecting layer or diffusing layer is effective in improving the light extraction efficiency. In particular, reflecting light scattered in a direction opposite to the desired irradiation direction in the irradiation direction is important for further improving the light extraction efficiency. In a light-emitting diode type lighting fixture that requires a large amount of light, the number of light-emitting diode elements that can be provided as one light source has reached the limit, so even if it is only a few percent, reflection of light is possible as much as possible. It is desired to improve the rate.

  For example, in an existing light emitting diode type projector having an output power of a large capacity such that the output power of the light source exceeds 300 W, in order to make the light emitted from a large number of light emitting diode elements apparently be the light of one light source Hundreds of light emitting diode elements are disposed on a substrate of about several tens mm to several tens of mm square. Therefore, if the reflective layer is formed on the entire surface of the substrate having low thermal conductivity, the required heat dissipation effect cannot be obtained and the probability of damaging the light emitting diode module is further increased.

  In view of the above problems, it is a primary object of the present invention to provide an improved light-emitting diode module capable of sufficiently suppressing a decrease in heat dissipation effect and durability and improving light extraction efficiency. The benefits that can be obtained by the light emitting diode module of the present invention will be described in detail in the description of the embodiments.

  In order to solve the above problems, a light emitting diode module of the present invention has a copper substrate (3) and a plurality of light emitting diode elements (2) disposed in a predetermined region (α) on the copper substrate (3). And a plurality of light emitting diode elements (2) fixed in an electrically insulated state so that the entire surface is in close contact with a predetermined region (α) of the copper substrate (3). A reflecting plate (5) for reflecting light traveling in the direction of (3), a titanium oxide thin film (7) formed by vacuum deposition provided on the entire reflecting surface side of the reflecting plate (5), and a phosphor And a package (11) enclosing a plurality of light emitting diode elements (2) on the copper substrate (3) together with the reflector (5) by the light-transmitting resin.

  In the more effective light emitting diode module (1), the reflector (5) is made of aluminum. As for the reflecting plate (5) made of aluminum, it is desirable to form an aluminum thin film by vacuum deposition on the entire surface on the reflecting surface side.

  Moreover, a preferable light emitting diode module (1) is formed by bonding the reflector (5) to the copper substrate (3) with a silicon paste mixed with an appropriate amount of aluminum fine powder. The light emitting diode module (1) has a plating layer (4) in addition to at least the predetermined region (α) of the copper substrate (3). The plating layer (4) is preferably a nickel plating layer.

  The light emitting diode module of the present invention is formed by attaching a reflector on which a titanium oxide thin film is formed in close contact with a copper substrate. Therefore, the heat generated by the light emitting diode element is transmitted to the outside of the diode module in a short time, and suppresses the deterioration of the heat dissipation effect. Since the titanium oxide thin film formed by vacuum deposition substantially passes the surface of the original reflector, visible light directed to the copper substrate side of the light-emitting diode element is reversed more efficiently in the irradiation direction. The titanium oxide thin film reflects light having a specific wavelength, for example, with which an aluminum reflector cannot provide sufficient reflectance.

  The light emitting diode module of the present invention improves the light extraction efficiency by increasing the reflectance of visible light toward the substrate side. In addition, an increase in the temperature around the light source is suppressed as the reflectance increases. As a result, in a large-capacity light-emitting diode type lighting fixture in which many light-emitting diode elements are arranged close to each other so as to be integrated on a single substrate to form a single light source, and the output power at the light source is relatively large, Illuminance can be improved.

It is sectional drawing which shows the structure of the light emitting diode module of this invention. It is a perspective view which shows the outline of the light emitting diode module of this invention.

  FIG. 1 shows a suitable embodiment of the light emitting diode module of the present invention. FIG. 1 schematically shows a longitudinal section of a light emitting diode module according to an embodiment. FIG. 1 does not accurately reflect the size of each part in order to show basically all important parts in the drawing. FIG. 2 shows an appearance of the light emitting diode module according to the embodiment shown in FIG. FIG. 2 shows a light-emitting diode module according to an embodiment designed to be applied to a light-emitting diode projector having an output power of a light source of 360 W. The configuration of the module according to the embodiment shown in the drawings will be specifically described below.

  In the light emitting diode module 1 of the embodiment, a plurality of light emitting diode elements 2 (2A, 2B, 2C) are arranged in a predetermined region α on the copper substrate 3 with a predetermined interval L. The light-emitting diode element 2 shown in FIG. 1 has a well-known general configuration in which each semiconductor layer and an electrode are stacked on a sapphire insulating substrate. Therefore, the light emitting diode module 1 according to the embodiment has a chip on board (COB) structure.

  The plurality of light emitting diode elements 2 (2A, 2B, 2C) are arranged at intervals of a length L so as to appear as one light source. In the light emitting diode module 1 of the embodiment shown in FIG. 1, all the light emitting diode elements 2 are arranged at equal intervals. Depending on the planar shape of the light emitting diode elements 2, the interval in the vertical arrangement of the light emitting diode elements 2 and the interval in the horizontal arrangement may be different.

  In the light emitting diode module 1 of the embodiment shown in FIG. 2, 400 chip type light emitting diode elements 2 are arranged in a predetermined region α on a 140 mm × 140 mm copper substrate 3. Electrically, series circuits in which several light emitting diode elements 2 are connected in series are connected in parallel.

  A metal plating for protecting the copper substrate 3 from corrosion is applied to the surface on the light emitting surface side of the copper substrate 3. In the following description, the surface of the copper substrate 3 on which the light emitting diode element 2 is attached is referred to as a light emitting surface, and the surface opposite to the light emitting surface is referred to as a non-light emitting surface. The plating layer 4 formed by metal plating is provided uniformly on at least a surface other than the predetermined region α on the light emitting surface of the copper substrate 3. In the light emitting diode module 1 of the embodiment, the plating layer 4 is provided on the entire surface of the copper substrate 3 on the light emitting surface side.

  The plating material of the plating layer 4 is nickel. The plating layer 4 is formed by an electric plating method. The plating thickness of the nickel plating layer 4 of the embodiment is about 20 μm. As the plating material for the plating layer 4, a metal having high plating performance against copper, which is effective for protecting the copper substrate 3, can be used in addition to nickel, but it is assumed that the light emitting diode module 1 forms a light source having a relatively large light amount. Therefore, a metal having good thermal conductivity is selected.

  The reflecting plate 5 reflects light traveling in the direction of the copper substrate 2 out of the light emitted from the light emitting diode element 2 in the normal irradiation direction. In the following description, the surface of the reflecting plate 5 on which the light emitting diode element 2 is attached is referred to as a reflecting surface, and the surface opposite to the reflecting surface is referred to as a non-reflecting surface. The reflecting plate 5 is attached and fixed so that the entire surface is in close contact with a predetermined region α on the light emitting surface side of the copper substrate 3. A plurality of light emitting diode elements 2 are mounted on the surface of the reflecting plate 5 on the reflecting surface side, and are fixed in an electrically insulated state.

  As the material of the reflector 5, a material that can achieve a reflectance of 90% or more is selected. In addition, since it is assumed that the light emitting diode module 1 can form a light source having a relatively large amount of light, a material having a relatively good thermal conductivity is selected as the material of the reflector 5.

  The reflecting plate 5 in the light emitting diode module 1 of the embodiment is an aluminum plate. The aluminum reflector 5 is appropriate in relation to the titanium oxide thin film 7 described later. In order to improve the reflectivity of visible light of the reflecting plate 5, aluminum or silver particles can be uniformly adhered to the entire surface of the reflecting surface of the aluminum reflecting plate 5 by vacuum deposition.

  In the present invention, silver is an example of a metal material applicable to the reflector 5 other than aluminum. However, silver is sulfided to cause discoloration due to alteration, and may reduce the reflectance of visible light. When a material that is easily altered is applied to the reflecting surface of the reflector, measures against the alteration may be required.

  The aluminum reflector 5 is bonded by a silicon paste 6 in which an appropriate amount of fine aluminum powder having a relatively high thermal conductivity is mixed with a nickel plating layer 4 formed on the surface of the copper substrate 3 interposed therebetween. Since the copper substrate 3 and the reflecting plate 5 are closely contacted by the flexible silicon paste 6 containing fine aluminum powder, the contact area between the copper substrate 3 and the reflecting plate 5 can be maximized. As high a thermal conductivity as possible.

  The nickel plating layer 4 is not so high in thermal conductivity. However, since nickel is not at least a heat insulating material and has a plating thickness of about a dozen μm, it does not significantly affect the heat dissipation effect of the light source. However, the plating layer 4 in a predetermined region α in close contact with the reflecting plate 5 with the silicon paste 6 interposed on the light emitting surface side on the copper substrate 3 can be limitedly removed. When the copper substrate 3 is in direct contact with the aluminum reflecting plate 5, it can be expected that the thermal conductivity is further increased even if it is slight.

  The flexible silicon paste 6 absorbs the difference in thermal expansion between the copper substrate 3 and the aluminum reflector 5. In the light emitting diode module 1 according to the embodiment having a relatively large surface area of the substrate, the collapse of the adhesion between the copper substrate 3 which may reach 70 ° C. and the copper substrate 3 due to the thermal displacement of the aluminum reflector 5 or the light emission. The deformation of the diode module 1 can be prevented.

  A titanium oxide thin film 7 formed by vacuum deposition is provided on the entire surface of the aluminum reflecting plate 5 on the reflecting surface side. The film thickness of the titanium oxide thin film 7 by vacuum deposition is basically a thinness close to the particle level, and is several hundred nm to several μm. Accordingly, the titanium oxide thin film 7 does not microscopically cover the aluminum reflecting plate 5 and substantially transmits the surface on the reflecting surface side of the aluminum reflecting plate 5. Therefore, the titanium oxide thin film 7 formed by vacuum deposition does not lose the function of reflecting the visible light of the aluminum reflector 5.

  The aluminum reflector 5 having the titanium oxide thin film 7 formed by vacuum deposition reflects visible light traveling in the direction of the copper substrate 3 with high reflectivity in the normal irradiation direction. The wavelength of light emitted from the light emitting diode element 2 is about 400 nm to 800 nm, but the aluminum reflector 5 cannot reflect light having a specific wavelength of about 700 nm to 800 nm with high reflectance. The titanium oxide thin film 7 scatters light of a specific wavelength that cannot be sufficiently reflected by the aluminum reflector 5. As a result, the reflection plate 5 as a whole can obtain a high reflectance of 97% at the maximum.

  In the light emitting diode module 1 of the embodiment, the titanium oxide thin film (vacuum deposited film) by vacuum deposition is, for example, a resin layer (light transmissive resin film) in which fine powder of titanium oxide (titanium dioxide) is mixed in a light transmissive resin. ) Cannot be practically replaced.

  The vacuum deposited film obtains a slightly higher reflectance than the transmissive resin film. A slight difference in reflectance greatly affects the performance of the light source. Moreover, since the light-transmitting resin film is basically thermally insulating, the thermal conductivity is lowered. In a light-emitting diode module that has a relatively large amount of light and is more likely to be damaged by heat generation, a decrease in thermal conductivity between the light-emitting diode element and the copper substrate causes a decrease in the heat dissipation effect that cannot be ignored. May cause damage.

  As shown in FIG. 1, the plurality of light emitting diode elements 2 (2A, 2B, 2C) are arranged in a predetermined region α on the copper substrate 3 with an aluminum reflector 5 interposed therebetween. Each light emitting diode element 2 is fixed on the aluminum reflector 5 by die bonding. When the bonding material 8 is regarded as a coating layer, a material that is electrically insulated from the copper substrate 3 and the reflection plate 5 is desirable. For the bonding material 8, for example, a heat insulating thermosetting resin such as an epoxy resin can be applied.

  As already described, the light-emitting diode element 2 has a chip-type configuration, and each layer and an electrode are stacked on an insulating sapphire substrate. Therefore, even if the bonding material 8 has a conductive property, the light emitting diode element 2 and the copper substrate 3 and the reflection plate 5 are electrically insulated.

  Therefore, although it is safer that the bonding material 8 is a material having electrical insulation, it is not strictly required to have electrical insulation, and a fine powder having thermal conductivity is mixed into the bonding material 8. Or a material that prioritizes thermal conductivity can be selected. In particular, when a light source having a large amount of heat and a large amount of light is formed, at the same time, in order to obtain as high a heat dissipation effect as possible, the light-emitting diode element 2 is bonded to the aluminum reflector with an adhesive having thermal conductivity as much as possible. It is desirable to fix to 5.

  On the light emitting surface side of the copper substrate 3, a flexible wiring substrate 9 made of polyimide or polyester is attached on the outer surface of the predetermined region α where the aluminum reflector 5 is provided. On the flexible wiring board 9, suitable wirings for supplying currents to the plurality of light emitting diode elements 2 are printed in advance.

  In the light emitting diode module 1 of the embodiment, as shown in FIG. 2, in order to more easily attach and fix the light emitting diode module 1 as a light source to the main body of the projector, a copper substrate 3 is attached to an aluminum heat sink (not shown). In the periphery of the substrate mounting part, the surface on the light emitting surface side of the copper substrate 3 on which the plating layer 4 is provided is partially exposed. However, since the light emitting surface of the light emitting diode module 1 may receive sunlight directly, the copper substrate 3 does not have to be exposed.

  As shown in FIG. 2, all the light emitting diode elements 2 disposed on a predetermined region α on the light emitting surface side surface of the copper substrate 3 include a phosphor together with an aluminum reflecting plate 5 corresponding to a base. It is sealed in one package 11 by a light transmissive resin 13. The package 11 that accommodates all the light emitting diode elements 2 is essentially composed only of the outer frame. The outer frame is provided on the flexible wiring board 9. Apparently, the light emitting diode module 1 forms one light source 11.

  In each light emitting diode element 2, wiring by the conducting wire 12 made of gold wire or copper wire is performed by wire bonding. The conducting wire 12 is connected to the printed wiring of the flexible wiring board 9 in the package 11. The conducting wire 12 is accommodated in the package 11 together with the aluminum reflector 5 and the plurality of light emitting diode elements 2 (2A, 2B, 2C).

  An appropriate amount of yellow phosphor is mixed in the light-transmitting portion 13 formed of the light-transmitting resin in consideration of the desired color of light. The light-transmitting portion 13 of the light-emitting diode module according to the embodiment is formed by mixing a hyalon-based phosphor with silicon resin. Therefore, in the light emitting diode module 1 shown in FIG. 2, when the light emitting diode element 2 is not emitting light, the light source 10 as a whole looks yellow.

  The copper substrate 3 is attached to, for example, an aluminum heat sink having a large number of large fins (not shown). A thin elastic body having high thermal conductivity such as a graphite sheet is interposed between the copper substrate 3 and the heat sink, and the copper substrate 3 is closely attached to the heat sink without any gap. Therefore, the heat of the light source emitted by the light emitting diode element 2 is transmitted to the heat sink in a relatively short time and is radiated to the atmosphere.

  In the case of the light-emitting diode module 1 according to the embodiment, the light-emitting diode module 1 includes the aluminum reflecting plate 5 provided with the titanium oxide thin film 7, has 400 light-emitting diode elements 2, and has the same output power as the previous light emission. When the total luminous flux of the diode module was 30,297 lm, the total luminous flux was 43,874 lm, and the illuminance was improved by 44.81%. For reference, the light emitting diode module 1 according to the embodiment has a color temperature of 5360K and a color rendering property of 53Ra.

  The light emitting diode module of the embodiment configured as described above can be disposed so as to integrate a large number of light emitting diode elements in a chip-on-board structure, and apparently one light source. The light-emitting diode module according to the embodiment can be used as a light source of a lighting fixture having a relatively large amount of light. At this time, since a large number of light emitting diode elements are arranged on a single substrate, the light emitting diode module may be damaged if the output power is increased.

  The light emitting diode module according to the embodiment can obtain a higher reflectance by a reflector having a titanium oxide thin film formed by vacuum deposition on the surface, and can obtain higher illuminance without increasing the output voltage. Therefore, the heat generation amount does not increase. Moreover, the improvement in the reflectance of visible light promotes a decrease in the temperature around the light source. As a result, the light emitting diode module can be prevented from being damaged.

  The heat generated by the light emitting diode element is quickly transferred from the reflecting plate having a relatively high thermal conductivity to the copper substrate. The heat transferred to the copper substrate is transferred to the heat sink and dissipated into the atmosphere. By providing the reflecting plate, the thermal conductivity is reduced compared to the case where the heat of the light emitting diode element is directly transmitted to the copper substrate, so that the risk of damage to the light emitting diode element is increased, but in the module of the embodiment, Even if a reflector is provided, the decrease in thermal conductivity is sufficiently suppressed, and the light emitting diode element is not damaged.

  The light emitting diode module of the present invention is not limited to the same configuration as the light emitting diode module of the embodiment unless it is contrary to the technical idea of the present invention. Some examples have already been shown, but can be modified, replaced, or implemented in combination with other inventions.

  The present invention can be applied to a light-emitting diode type luminaire. In particular, it is suitable for a light-emitting diode type lighting apparatus having a large light quantity such as a large light-emitting diode type projector used in outdoor facilities. It can be expected to give light emitting diode lighting fixtures the same performance as mercury lamp lighting fixtures, promote the spread of light emitting diode lighting fixtures that consume less power and do not use harmful substances compared to mercury lamp lighting fixtures, and develop society To contribute.

DESCRIPTION OF SYMBOLS 1 Light emitting diode module 2 Light emitting diode element 3 Copper substrate 4 Metal plating layer 5 Reflecting plate 6 Silicon paste 7 Titanium oxide thin film (vacuum deposition film)
8 Bonding material 9 Flexible wiring board 10 Light source 11 Package 12 Conductor 13 Transmission part

As shown in FIG. 2, all the light emitting diode elements 2 disposed on a predetermined region α on the light emitting surface side surface of the copper substrate 3 include a phosphor together with an aluminum reflecting plate 5 corresponding to a base. It is sealed in one package 11 by a light transmissive resin 13. The package 11 that accommodates all the light emitting diode elements 2 is essentially composed only of the outer frame. The outer frame is provided on the flexible wiring board 9. Apparently, the light emitting diode module 1 forms one light source 10 .

An appropriate amount of yellow phosphor is mixed in the light-transmitting portion 13 formed of the light-transmitting resin in consideration of the desired color of light. The light-transmitting portion 13 of the light-emitting diode module according to the embodiment is formed by mixing a sialon-based phosphor with silicon resin. Therefore, in the light emitting diode module 1 shown in FIG. 2, when the light emitting diode element 2 is not emitting light, the light source 10 as a whole looks yellow.

Claims (7)

  A copper substrate, a plurality of light emitting diode elements disposed in a predetermined region on the copper substrate, and the plurality of light emitting diode elements attached to the predetermined region of the copper substrate so as to be in close contact with each other. A reflective plate that is fixed in an insulating state and reflects light directed toward the copper substrate out of the light from the light-emitting diode element; and a titanium oxide thin film formed by vacuum deposition provided on the entire surface of the reflective surface of the reflective plate; A light emitting diode module comprising:   The light emitting diode module according to claim 1, further comprising a package that encloses the plurality of light emitting diode elements together with the reflecting plate on the copper substrate with a light transmissive resin including a phosphor.   The light emitting diode module according to claim 1, wherein the reflector is made of aluminum.   4. The light emitting diode module according to claim 3, wherein an aluminum thin film is formed by vacuum deposition on the entire surface of the reflecting plate made of aluminum on the reflecting surface side.   2. The light emitting diode module according to claim 1, wherein the reflector is adhered to the copper substrate with a silicon paste mixed with an appropriate amount of aluminum fine powder.   The light emitting diode module according to claim 1, further comprising a plating layer other than at least the predetermined region of the copper substrate.   The light emitting diode module according to claim 6, wherein the plating layer is a nickel plating layer.

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