JP2006093399A - Light-emitting device, its manufacturing method and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device improving a wavelength conversion efficiency by a phosphor and enhancing an optical output from the light-emitting device while having excellent illumination characteristics such as a brightness, a color rendering or the like. <P>SOLUTION: The light-emitting device has a base body 1 in which a placing section 1a placing a light-emitting element 3 is formed on a top face; a frame-shaped reflecting member 2 which is joined so as to surround the placing section 1a to the outer peripheral section of the top face of the base body 1, and in which an inner peripheral surface 2a is formed in a reflecting surface reflecting a light emitted from the light-emitting element 3; and a first light-transmitting member 4 formed so as to coat the light-emitting element 3 on the inside of the reflecting member 2. The light-emitting device further has a second tabular light-transmitting member 5 which is formed so as to coat the first light-transmitting member 4 at an interval between the first light-transmitting member 4 and the inner peripheral surface, or top face of a frame body on the inner peripheral surface or the top face of the frame body and in which the phosphor 6 is distributed unevenly in a layer shape on the top face side. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a light emitting device that houses a light emitting element, a method for manufacturing the same, and a lighting device.

  A conventional light emitting device is shown in FIG. In FIG. 9, the light emitting device has a mounting portion 11a for mounting the light emitting element 13 at the center of the upper surface, and leads that electrically connect the inside and outside of the light emitting device from the mounting portion 11a and its periphery. A base 11 made of an insulator on which a wiring conductor (not shown) made of terminals, metallized wiring, etc. is formed, and adhesively fixed to the upper surface of the base 11 so that the inner peripheral surface 12a spreads outward as it goes upward. The inner peripheral surface 12a is a reflecting surface that reflects the light emitted from the light emitting element 13, and the light transmitted from the light emitting element 13 to the translucent member. It mainly comprises a wavelength conversion layer 15 containing a phosphor (not shown) for wavelength conversion, and a translucent member 16 filled inside the reflecting member 12 to protect the light emitting element 13. .

  The substrate 11 is made of an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, ceramics such as glass ceramics, or a resin such as epoxy resin. When the substrate 11 is made of ceramic, the wiring conductor is formed on its upper surface by firing a metal paste made of tungsten (W), molybdenum (Mo) -manganese (Mn), etc. at a high temperature. When the base 11 is made of a resin, lead terminals made of copper (Cu), iron (Fe) -nickel (Ni) alloy, etc. are molded and fixed inside the base 11.

  The reflecting member 12 is made of metal such as aluminum (Al) or Fe-Ni-cobalt (Co) alloy, ceramics such as alumina ceramics or resin such as epoxy resin, and is used for cutting, die molding, extrusion molding, etc. Formed by molding technique.

  Further, the reflecting member 12 has an inner peripheral surface 12a as a reflecting surface that reflects light from the light emitting element 13 and the wavelength conversion layer 15, and the inner peripheral surface 12a is made of a metal such as Al by vapor deposition or plating. It is formed by adhering. The reflecting member 12 is joined to the upper surface of the base 11 by a soldering material such as solder, silver (Ag) solder, or a joining material such as a resin adhesive so as to surround the mounting portion 11a with the inner peripheral surface 12a.

  The light-emitting element 13 is formed on a single crystal substrate such as sapphire by liquid phase growth method or MOCVD method, for example, gallium (Ga) -Al-nitrogen (N), zinc (Zn) -sulfur (S), Zn -Selenium (Se), Silicon (Si) -Carbon (C), Ga-Phosphorus (P), Ga-Al-Arsenic (As), Al-Indium (In) -Ga-P, In-Ga-N, Ga A light emitting layer such as -N or Al-In-Ga-N is formed. Examples of the structure of the light emitting element 13 include a homo structure having a MIS junction and a PN junction, a hetero structure, and a double hetero structure. Further, the emission wavelength of the light emitting element 13 is variously selected from ultraviolet light to infrared light depending on the material of the light emitting layer and the degree of mixed crystal thereof. Note that the light emitting element 13 has a method of using a bonding wire (not shown) for the wiring conductor arranged around the mounting portion 11a and the electrode of the light emitting element 13, or the electrode of the light emitting element 13 is installed on the lower side. Then, they are electrically connected by a method using a flip chip bonding method in which solder bumps are used for connection.

  In addition, the wavelength conversion layer 15 contains phosphors in a translucent member such as an epoxy resin or a silicone resin, and is thermally cured to form a plate and covers the opening of the reflecting member 12, thereby emitting from the light emitting element 13. The visible light and near-ultraviolet light, which are emitted light wavelengths, can be absorbed and converted into other long-wavelength light to be emitted. Accordingly, the wavelength conversion layer 15 is a light-emitting device that can extract light having a desired wavelength spectrum by using various types of light depending on the emission wavelength of the light emitted from the light-emitting element 13 or the desired light emitted from the light-emitting device. It can be done. The light emitting device can emit white light when the light emitted from the light emitting element 13 and the light from the phosphor are in a complementary color relationship.

  Examples of phosphors include yttrium / aluminum / garnet phosphors activated with cerium (Ce), perylene derivatives, zinc cadmium sulfide activated with Cu and Al, and magnesium oxide activated with Mn. Various types such as titanium oxide can be used. These phosphors may be used alone or in combination of two or more.

Furthermore, the translucent member 16 uses a translucent member such as an epoxy resin or a silicone resin to protect the light emitting element 13 and reduce the difference in refractive index between the light emitting element 13 and the translucent member. Accordingly, it is possible to suppress light from being confined inside the light emitting element 13.
JP 2000-349346 A

  In the conventional light emitting device, the phosphor is dispersed in the entire wavelength conversion layer 15 by injecting the liquid wavelength conversion layer 15 containing the phosphor on the upper surface of the translucent member 16 and thermally curing it. It was.

  However, the light emitted from the phosphor located on the lower side of the wavelength conversion layer 15 causes a light loss when passing through the wavelength conversion layer 15, and the light intensity emitted outside the light emitting device is reduced. There was a point.

  On the other hand, in order to increase the light intensity of the light-emitting device, it is possible to increase the intensity of light incident on the phosphor and increase the intensity of light emitted outside the light-emitting device by increasing the light-emitting intensity of the light-emitting element 13. is there.

  However, when the incident light intensity to the phosphor is relatively small, the intensity of the emitted light from the phosphor increases in proportion to the incident light intensity, but gradually becomes non-proportional as the incident light intensity increases. However, it is difficult to increase the light intensity of a desired wavelength that has been wavelength-converted, since the light emitted from the phosphor without being wavelength-converted by the phosphor is increased while the intensity of the emitted light remains constant. Had a point.

  In addition, light that travels downward after being wavelength-converted to a phosphor, or light of a light-emitting element that is reflected downward without being wavelength-converted by the phosphor is diffusely reflected inside the light-emitting device, and the light-emitting element, substrate, etc. There is also a problem that light loss occurs due to absorption by the light.

  Accordingly, the present invention has been completed in view of the above-described conventional problems, and an object of the present invention is to provide a light emitting device having high radiated light intensity and high luminance and high luminous efficiency.

  The light emitting device of the present invention is bonded to a base having a mounting portion on which the light emitting element is mounted on the upper surface and an outer peripheral portion of the upper surface of the base so as to surround the mounting portion, and an inner peripheral surface is A frame-like reflecting member that is a reflecting surface that reflects light emitted from the light emitting element, and a first light transmissive member formed so as to cover the light emitting element inside the reflecting member; The inner surface or upper surface of the frame body is provided so as to cover the first light transmissive member with a gap between the frame and the first light transmissive member, and the phosphor is layered on the upper surface side. And a plate-like second translucent member that is unevenly distributed.

  The light emitting device of the present invention is bonded to a base having a mounting portion on which the light emitting element is mounted on the upper surface and an outer peripheral portion of the upper surface of the base so as to surround the mounting portion, and an inner peripheral surface is A frame-like reflecting member that is a reflecting surface that reflects light emitted from the light emitting element, and a first light transmissive member formed so as to cover the light emitting element inside the reflecting member; A plate-like second light-transmitting member provided so as to cover the first light-transmitting member and having a refractive index larger than that of the first light-transmitting member and phosphors being unevenly distributed on the upper surface side. It is characterized by having a sex member.

  The manufacturing method of the present invention is a manufacturing method of the above-described light-emitting device of the present invention, the step of bonding the reflecting member to the outer peripheral portion of the upper surface of the base, and the step of mounting the light-emitting element on the mounting portion Injecting the liquid first translucent member inside the reflective member so as to cover the light emitting element, and then curing the first translucent member; and a liquid containing the phosphor A step of forming the second translucent member into a plate shape, and the phosphor in the second translucent member is allowed to settle to one main surface side, and then the second translucent member is A step of curing, and a step of attaching the cured second light-transmitting member so as to cover the light emitting element on the upper surface or the inner peripheral surface of the reflecting member so that the one main surface side is on the upper side. It is characterized by comprising.

  The manufacturing method of the present invention is a manufacturing method of the above-described light-emitting device of the present invention, the step of bonding the reflecting member to the outer peripheral portion of the upper surface of the base, and the step of mounting the light-emitting element on the mounting portion Injecting the liquid first translucent member inside the reflecting member so as to cover the light emitting element; and the first translucent member having a refractive index larger than that of the first translucent member and including the phosphor. A step of forming the light transmissive member in a plate shape, and the phosphor in the second light transmissive member is allowed to settle to one main surface side, and then the second light transmissive member is cured. A step of covering the first translucent member with the upper surface of the first translucent member such that the one main surface side is the upper side of the cured second translucent member And a step of attaching to the substrate.

  The light-emitting device according to the first aspect of the present invention is bonded to the base on which the mounting portion for mounting the light-emitting element is formed on the upper surface, and the outer periphery of the upper surface of the base so as to surround the mounting portion. A frame-like reflecting member whose inner peripheral surface is a reflecting surface that reflects light emitted from the light emitting element, and a first light transmissive member formed so as to cover the light emitting element inside the reflecting member; The inner peripheral surface or the upper surface of the frame body is provided so as to cover the first light transmissive member with a gap between the first light transmissive member and the phosphors are unevenly distributed in a layered manner on the upper surface side. By providing the plate-like second translucent member, the light wavelength-converted by the phosphor can be efficiently emitted to the outside of the light emitting device with strong radiated light intensity and high luminance.

  Conventionally, the phosphor is dispersed throughout the wavelength conversion layer. Among the phosphors present in the entire wavelength conversion layer, for the phosphors present below, the emission intensity of the light emitting element can be increased so that the phosphor can be excited and emit light with the maximum emitted light intensity. In addition, light loss increases by irregularly reflecting between phosphors without passing through the wavelength conversion layer while passing through the wavelength conversion layer, and only light emitted outside without wavelength conversion is increased. The intensity of light that has been wavelength-converted and emitted to the outside of the light-emitting device has become weak.

  However, in the present invention, since the phosphors are unevenly distributed in layers above the second light transmissive member, the light emitted from the light emitting element reaches the phosphor after passing through the second light transmissive member. At that time, even if the emission intensity of the light-emitting element is increased so that the phosphor is excited and can emit light with the maximum emission light intensity, the light passes through the second translucent member after wavelength conversion. Since it travels to a very short path and is immediately emitted to the outside, it is emitted to the outside of the light emitting device with almost no light loss.

  That is, according to the present invention, the light wavelength-converted by the phosphor can be efficiently emitted to the outside of the light emitting device with strong radiated light intensity and high luminance.

  In addition, there is a gap below the second light-transmissive member for light that travels downward after being wavelength-converted to the phosphor, or light from the light-emitting element that is reflected by the phosphor without being wavelength-converted. Thus, it becomes easy to totally reflect at the interface between the gap and the lower surface of the second translucent member, and is favorably reflected upward. As a result, it is possible to suppress light loss caused by light that travels downward after being wavelength-converted into a phosphor and is diffusely reflected inside the light-emitting device and absorbed by the light-emitting element or the substrate. Furthermore, the light of the light emitting element reflected downward without being wavelength-converted by the phosphor irradiates the phosphor again, which improves the wavelength conversion efficiency and increases the intensity of the emitted light extracted outside. it can.

  Of the light that is wavelength-converted by the phosphor and travels in all directions, the light emitted downward has a gap below the second light transmissive member, so that the gap and the second light transmissive property are reduced. It becomes easy to totally reflect at the interface with the lower surface of the member, and can be reflected upward. Since the wavelength-converted light travels upward, it becomes difficult to be absorbed by the light emitting element, the substrate, and the like, so that the intensity of radiated light extracted outside the light emitting device is increased.

  In addition, by narrowing the interval between the phosphors to form a moderately dense layer and making the thickness of the layered phosphor uniform, it is possible to suppress uneven color and intensity distribution on the light emitting surface and the irradiated surface. It is possible to manufacture a lighting device having a color rendering property with a stable illuminance distribution.

  Furthermore, when the light generated from the light emitting element is in the ultraviolet light region from near-ultraviolet light of 400 nm or less, it is possible to suppress the light that is transmitted without being wavelength-converted through the gaps between the phosphors, and to reduce the influence on the human body. .

  The light emitting device according to the second aspect of the present invention is bonded to the base on which the mounting portion for mounting the light emitting element is formed on the upper surface, and the outer periphery of the upper surface of the base so as to surround the mounting portion. A frame-like reflecting member whose inner peripheral surface is a reflecting surface that reflects light emitted from the light emitting element, and a first light transmissive member formed so as to cover the light emitting element inside the reflecting member; The inner peripheral surface or the upper surface of the frame body is provided so as to cover the first translucent member, and the refractive index is larger than that of the first translucent member, and the phosphors are unevenly distributed on the upper surface side. By providing the plate-like second translucent member, light emitted from the light-emitting element can be emitted to the outside with high radiant light intensity and high luminance with high luminous efficiency.

  That is, light emitted from the light emitting element is transmitted through the second light transmissive member and emitted to the outside of the light emitting device. Since the phosphor is unevenly distributed on the upper surface side of the second translucent member, the light emitted from the light emitting element is transmitted through the phosphor, adjusted to a desired light color, and emitted to the outside.

  Conventionally, the phosphor is dispersed throughout the wavelength conversion layer. Among the phosphors present in the entire wavelength conversion layer, for the phosphors present below, the emission intensity of the light emitting element can be increased so that the phosphor can be excited and emit light with the maximum emitted light intensity. In addition, light loss increases by irregularly reflecting between phosphors without passing through the wavelength conversion layer while passing through the wavelength conversion layer, and only light emitted outside without wavelength conversion is increased. The intensity of light that has been wavelength-converted and emitted to the outside of the light-emitting device has become weak.

  However, in the present invention, since the phosphors are unevenly distributed in layers above the second light transmissive member, the light emitted from the light emitting element reaches the phosphor after passing through the second light transmissive member. At that time, even if the emission intensity of the light-emitting element is increased so that the phosphor is excited and can emit light with the maximum emission light intensity, the light passes through the second translucent member after wavelength conversion. Since it is emitted to the outside immediately after traveling a short path, it is emitted to the outside of the light emitting device with almost no light loss.

  That is, according to the present invention, the light wavelength-converted by the phosphor can be efficiently emitted to the outside of the light emitting device with strong radiated light intensity and high luminance.

  In addition, light that travels downward after being wavelength-converted to the phosphor, or light of the light emitting element that is reflected downward without being wavelength-converted by the phosphor, is transmitted from the first translucent member to the second translucent light. Since the refractive index of the translucent member is larger, total reflection is likely to occur at the interface between the upper surface of the first translucent member and the lower surface of the second translucent member, and the upper member is favorably reflected upward. As a result, it is possible to suppress light loss caused by light that travels downward after being wavelength-converted into a phosphor and is diffusely reflected inside the light-emitting device and absorbed by the light-emitting element or the substrate. Furthermore, the light of the light emitting element reflected downward without being wavelength-converted by the phosphor irradiates the phosphor again, which improves the wavelength conversion efficiency and increases the intensity of the emitted light extracted outside. it can.

  In addition, among the light that has been wavelength-converted to the phosphor that travels in any direction, the light emitted downward has a higher refractive index of the second light transmissive member than the first light transmissive member. It becomes easy to totally reflect at the interface between the upper surface of the first translucent member and the lower surface of the second translucent member, and can be reflected upward. As the wavelength-converted light travels in the upward direction in this way, it becomes difficult to be absorbed by the light emitting element, the substrate, etc., and the intensity of the emitted light extracted outside the light emitting device is increased.

  In addition, by narrowing the interval between the phosphors to form a moderately dense layer and making the thickness of the layered phosphor uniform, it is possible to suppress uneven color and intensity distribution on the light emitting surface and the irradiated surface. It is possible to manufacture a lighting device having a color rendering property with a stable illuminance distribution.

  Furthermore, when the light generated from the light emitting element is in the ultraviolet light region from near-ultraviolet light of 400 nm or less, it is possible to suppress the light that is transmitted without being wavelength-converted through the gaps between the phosphors, and reduce the influence on the human body .

  The method for manufacturing a light emitting device according to the present invention includes a step of bonding a reflective member to the outer peripheral portion of the upper surface of the base, a step of mounting the light emitting element on the mounting portion, and reflecting the liquid first translucent member. A step of curing the first light-transmitting member after injecting the light-emitting element inside the member, a step of forming a liquid second light-transmitting member containing a phosphor into a plate shape, The step of allowing the phosphor in the translucent member of 2 to settle to one main surface side and then curing the second translucent member, and the one main surface side of the cured second translucent member to be on the upper side And the step of covering and attaching the light emitting element to the upper surface or inner peripheral surface of the reflecting member so that the phosphor is easily provided on the one main surface side of the second light transmissive member. In addition, a light-emitting device that can be uniformly distributed in a layer shape, has a small intensity distribution, and has high light emission efficiency can be easily manufactured.

  The method for manufacturing a light emitting device according to the present invention includes a step of bonding a reflecting member to the outer peripheral portion of the upper surface of the base, a step of mounting the light emitting element on the mounting portion, and a liquid first light transmissive member as the reflecting member. A step of injecting the light emitting element so as to cover the light emitting element, a step of forming a second light transmissive member having a refractive index larger than that of the first light transmissive member and including a phosphor into a plate shape, After the fluorescent substance in the translucent member is settled to one main surface side, the step of curing the second translucent member, and the one main surface side of the cured second translucent member are on the upper side The main surface side of the second translucent member by comprising the step of attaching the upper surface of the first translucent member to cover the first translucent member In addition, phosphors can be easily and uniformly unevenly distributed in layers, and a light emitting device with high emission efficiency with little uneven intensity distribution can be easily manufactured. .

  Since the lighting device of the present invention is installed so as to have a predetermined arrangement, the lighting device of the present invention is higher than the lighting device in which the conventional phosphors are dispersed because the phosphor exists above. It can be set as a luminance lighting device. As a result, it is possible to irradiate light with a stable radiant light intensity, and it is possible to provide an illuminating device in which color unevenness and uneven illuminance distribution on the irradiated surface are suppressed.

  In addition, the light emitting device of the present invention is installed in a predetermined arrangement as a light source, and by installing a reflection jig, an optical lens, a light diffusing plate, etc. optically designed in an arbitrary shape around these light emitting devices, It can be set as the illuminating device which radiates | emits the light of this light distribution.

  The light-emitting device according to the first aspect of the present invention will be described in detail below. FIG. 1 is a cross-sectional view showing an example of an embodiment of a light emitting device of the present invention. In this figure, 1 is a base, 2 is a reflecting member, 4 is a first translucent member injected so as to cover the light emitting element 3 inside the reflecting member 2, and 5 is above the light emitting element 3 and the first A second translucent member disposed on the inner peripheral surface 2 a or the upper surface of the reflecting member 2 with a gap between the translucent member 4 and the upper surface side of the second translucent member 5. Is a phosphor that generates fluorescence by converting the wavelength of light emitted by the light-emitting element 3, and a light-emitting device for housing the light-emitting element 3 is mainly composed of these phosphors.

  The substrate 1 is made of alumina ceramic, aluminum nitride sintered body, mullite sintered body, ceramic such as glass ceramic, metal such as Fe-Ni-Co alloy or Cu-W, or resin such as epoxy resin, A placement portion 1 a on which the light emitting element 3 is placed is formed on the upper surface of the base 1.

  The base 1 is attached to the upper surface with a bonding material such as solder, a brazing material such as Ag brazing, or a resin adhesive such as an epoxy resin so that the reflecting member 2 surrounds the mounting portion 1a. The reflecting member 2 has a desired surface accuracy around the light emitting element 3 (for example, in the longitudinal section of the light emitting device, light reflecting surfaces provided on both sides of the light emitting element 3 with the light emitting element 3 interposed therebetween are symmetrical. In this state, the inner peripheral surface 2a is attached. Therefore, even if the light emitted from the light emitting element 3 travels in the lateral direction, it can be favorably reflected upward by the reflecting member 2 and travel toward the second light transmissive member 5. The emitted light is wavelength-converted by the phosphor 6 and is efficiently emitted to the outside of the light emitting device. As a result, since the light emitting device can immediately emit the wavelength-converted light to the outside, the light emitting device has high radiated light intensity and high luminance, and can improve luminous efficiency.

  Moreover, it is preferable that the mounting portion 1a protrudes so that the height is higher than the lower end of the inner peripheral surface 2a of the first reflecting member 2 as shown in FIG. Accordingly, even light emitted obliquely downward from the light emitting element 3 efficiently travels upward by the reflecting member 2, so that the light emitting element is wavelength-converted by the phosphor 6 after passing through the second light transmissive member 5. The light of No. 3 increases, and the emitted light intensity of the light emitting device is improved.

  The protruding mounting portion 1a is integrally fired by removing the periphery thereof by polishing, cutting, etching or the like, or by laminating the ceramic green sheets to be the base 1 and the mounting portion 1a. Thus, it is formed so as to protrude from the upper surface of the substrate 1. Alternatively, another member that becomes the mounting portion 1a may be attached to and formed on the upper surface of the base 1 with an adhesive or the like. For example, alumina ceramics, aluminum nitride sintered bodies, mullite sintered bodies, ceramics such as glass ceramics, silicon (Si) substrates, metals such as Fe-Ni-Co alloys and Cu-W, or epoxy resins A member to be the mounting portion 1a made of resin can be provided by attaching to the upper surface of the base 1 with a bonding material such as a brazing material or an adhesive.

  Moreover, as shown in FIG. 4, it is preferable that the mounting part 1a is inclined so that its side surface expands outward as it goes downward. Thereby, when the first translucent member 4 made of a liquid resin before thermosetting is injected into the inside of the reflecting member 2, the protruding mounting portion 1a and the upper surface of the base 1 or the inner peripheral surface 2a It is possible to effectively prevent bubbles and air pockets from being formed at the corners between the lower ends. Furthermore, the light emitted from the light emitting element 3 is favorably reflected in the upward and inner peripheral surface 2a directions by the side surface of the protruding mounting portion 1a, and the emitted light intensity of the light emitting device can be further improved. Furthermore, the heat generated in the light emitting element 3 is efficiently diffused and transmitted to the base 1 side via the mounting portion 1a, so that the temperature rise of the light emitting element 3 is more effectively suppressed.

  Further, the mounting portion 1a is formed with a wiring conductor (not shown) for electrically connecting the light emitting element 3. The wiring conductor is led to the outer surface of the light emitting device via a wiring layer (not shown) formed inside the base 1 and connected to an external electric circuit, whereby the light emitting element 3 and the external electric circuit are connected. It will be electrically connected.

  The reflecting member 2 is made by cutting or molding a metal having a high reflectivity such as Al, Ag, gold (Au), platinum (Pt), titanium (Ti), chromium (Cr), or Cu. It is formed by. Alternatively, the reflecting member 2 is made of an insulator such as ceramic or resin, and a metal thin film having a high reflectivity such as Al, Ag, Au, Pt, Ti, Cr, or Cu is formed on the inner peripheral surface 2a by plating or vapor deposition. It may be formed. Among these, when the inner peripheral surface 2a is made of a metal that is easily discolored by oxidation such as Ag or Cu, for example, an Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer having a thickness of about 0.1 to 3 μm are formed on the surface. Is preferably deposited sequentially by electrolytic plating or electroless plating. Thereby, the corrosion resistance of the inner peripheral surface 2a is improved and the deterioration of the reflectance is suppressed.

  Furthermore, the arithmetic average roughness Ra of the inner peripheral surface 2a is preferably 0.004 to 4 μm, and thus the light from the light emitting element 3 can be reflected well. When Ra exceeds 4 μm, the light from the light emitting element 3 is not reflected uniformly, but diffusely reflects inside the light emitting device, and the light loss tends to increase. On the other hand, if it is less than 0.004 μm, it tends to be difficult to form such a surface stably and efficiently.

  Further, the reflecting member 2 has no problem even if the longitudinal sectional shape of the outer peripheral surface is changed to a curved shape.

  The light emitting element 3 is electrically connected to the wiring conductor formed on the substrate 1 by wire bonding or a flip chip bonding method in which the electrodes of the light emitting element 3 are connected to each other by solder bumps. Preferably, the connection is made by a flip chip bonding method. Thereby, since the wiring conductor can be provided immediately below the light emitting element 3, it is not necessary to provide a space for providing the wiring conductor on the upper surface of the base 1 around the light emitting element 3. Therefore, it is possible to effectively suppress the light emitted from the light emitting element 3 from being absorbed in the space of the wiring conductor of the base body 1 and the radiation light intensity from being lowered.

  This wiring conductor is formed by, for example, forming a metallized layer of a metal powder such as W, Mo, Cu, Ag, or by burying a lead terminal such as an Fe-Ni-Co alloy, or by forming a wiring conductor. An input / output terminal made of an insulating material is provided by being fitted and joined to a through hole provided in the base 1.

  It should be noted that the exposed surface of the wiring conductor should be coated with a metal having excellent corrosion resistance, such as Ni or Au, with a thickness of about 1 to 20 μm, which can effectively prevent oxidative corrosion of the wiring conductor. The electrical connection between the light emitting element 3 and the wiring conductor can be strengthened. Therefore, for example, an Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer having a thickness of about 0.1 to 3 μm are sequentially deposited on the exposed surface of the wiring conductor by an electrolytic plating method or an electroless plating method. Is more preferable.

  The first light transmissive member 4 and the second light transmissive member 5 are made of transparent resin such as epoxy resin or silicone resin, or light transmissive glass, and are formed so as to cover the light emitting element 3. Injected into the reflection member 2. Thereby, the refractive index difference between the inner side and the outer side of the light emitting element 3 is reduced, more light can be extracted from the light emitting element 3, the emission intensity is improved, and the emitted light intensity and the luminance can be remarkably improved.

  The second translucent member 5 is formed by containing the phosphor 6 in a translucent member such as an epoxy resin, a silicone resin, or glass, and the phosphor 6 is unevenly distributed in a layered manner on the upper surface side.

  Such a phosphor 6 is excited by light from the light emitting element 3 and can emit fluorescence having a desired wavelength. For example, the phosphor 6 is selected from alkaline earth aluminate phosphors and rare earth elements. Further, phosphors such as yttrium, aluminum, and garnet phosphors activated with at least one element, pigments, and the like are used.

  In the light emitting device of the present invention, the phosphor 6 is unevenly distributed in the form of a layer on the upper surface side of the second translucent member 5, whereby the emission intensity can be improved as follows.

  For example, as a condition that the phosphor 6 is excited and can emit light with the maximum emitted light intensity, when light having an intensity of 100 is incident on the phosphor 6 from the light emitting element 3, the excited phosphor 6 emits light. It is assumed that the maximum intensity of the outgoing light that is wavelength-converted and output is X.

  The light emitted from the light emitting element 3 is absorbed by the first light transmissive member 4, the gap, and the second light transmissive member 5 before reaching the phosphor 6. If the intensity is 110, light can be incident on the phosphor 6 at an intensity of 100, and the maximum emitted light intensity X can be emitted from the phosphor 6. Thereafter, the light emitted from the phosphor 6 with the intensity X travels through the second light-transmissive member 5 and travels to a very short path, and then is emitted to the outside. The light of the light emitting element 3 reflected by the light is easily totally reflected at the interface between the gap and the lower surface of the second light transmissive member 5 because there is a gap below the second light transmissive member 5. Reflected upward. For this reason, it can be emitted to the outside while maintaining the maximum emitted light intensity X (or a value close thereto).

  However, in the conventional light emitting device, even if the intensity of the light emitting element 13 is determined so that light is emitted from the phosphor with the maximum emitted light intensity, the light emitted from the light emitting element 13 is below the wavelength conversion layer 15. After being emitted from the phosphor existing at the intensity X, an optical loss occurs when passing through the wavelength conversion layer 15, and therefore when emitted outside the light emitting device, it is emitted outside at the maximum output light intensity X. I couldn't.

  As described above, the phosphor existing under the wavelength conversion layer has a loss due to a long path until it is emitted to the outside even when light is emitted with the maximum emitted light intensity, and is not wavelength-converted. Although the light emitted to the outside increases, in the present invention, since the phosphor 6 exists above the second translucent member 5, it is emitted to the outside immediately after being converted to the maximum emitted light intensity. In addition, since there is a gap below the second translucent member 5, the light of the light emitting element 3 that is reflected downward without being wavelength-converted by the phosphor 6 is reflected between the gap and the second translucency. It becomes easy to totally reflect at the interface with the lower surface of the member 5, and the light that is reflected upward and illuminates the phosphor 6 increases, and is emitted with strong radiated light intensity and high brightness.

  Here, even if the intensity of the light emitting element 13 in the conventional light emitting device is set to a large value such as 200 to increase the emitted light from the light emitting device, the light that can be emitted by wavelength conversion with the phosphor is already saturated. Therefore, it does not become larger than the maximum emitted light intensity X, and only the light emitted to the outside without being wavelength-converted is increased. For this reason, not only the intensity of the desired light cannot be improved, but also an unnecessary amount of light that is not wavelength-converted increases, thereby deteriorating the optical characteristics of the light emitting device.

  Here, in the present invention, the phosphor 6 is unevenly distributed on the upper surface side of the second translucent member 5 because 90% of the total mass of the phosphor 6 included in the second translucent member 5 is 90%. It means that% or more exists above half of the thickness of the second translucent member 5.

Preferably, the second translucent member 5 is inclined so that the concentration of the phosphor 6 gradually increases from the lower surface to the upper surface. As a result, the concentration change of the phosphor 6 in the thickness direction of the second translucent member 5 becomes gradual, so that distortion that is likely to occur when the concentration change is abrupt is suppressed, and there is no color unevenness or unevenness in strength. Light emission can be performed.

  More preferably, the concentration of the phosphor 6 gradually increases from the lower surface to the upper surface in the thickness direction of the second translucent member 5, and from the upper surface of the second translucent member 5, It is preferable that 60% to 70% of the total mass of the phosphor 6 is contained up to 1/3 of the thickness of the optical member 5. In addition, it is preferable that 30% to 10% of the total mass of the phosphor 6 is contained between one third and two thirds of the thickness of the second translucent member 5. Moreover, it is preferable to contain 0% to 10% of the total mass of the phosphor 6 from the two thirds of the thickness of the second translucent member 5 to the lower surface.

  Thus, although the fluorescent substance 6 is unevenly distributed in the 2nd translucent member 5, the content rate of the fluorescent substance 6 becomes small gradually from one main surface to the opposite main surface, The one main surface side The phosphor 6 is most unevenly distributed.

  Thereby, it is possible to effectively prevent the second translucent member 5 from being distorted, to secure an appropriate gap between the phosphors, and to prevent light from being blocked by the phosphors 6. Can be prevented.

  The manufacturing method of the 2nd translucent member 5 containing the fluorescent substance 6 produces several translucent members from which the content rate of a fluorescent substance differs, for example, and laminate | stacks it in order from a thing with a high content rate. 2 is formed so as to be inclined so that the content rate of the phosphor 6 gradually decreases from one main surface to the opposite main surface of the translucent member 5. It can be produced by a method such as attaching to the upper surface or inner peripheral surface 2a of the reflecting member 2 so as to be on the upper side.

  More preferably, after the uncured silicone resin containing the phosphor is vibrated to cause the phosphor 6 to settle to one main surface side and thermally cured, the one main surface side on which the phosphor 6 has settled is the upper side. It is good to attach to the upper surface or inner peripheral surface 2a of the reflecting member 2 so that it may become.

  The method of placing the second translucent member 5 containing the phosphor 6 in the light emitting device is, for example, by injecting the first translucent member 4 and thermosetting it, and then forming a gap on it. After placing the second translucent member 5 so that the one main surface side on which the phosphor 6 has settled is on the upper side so as to open and cover the first translucent member 4, the inner side or upper surface of the reflective member 2 It can be produced by a method such as attaching to the resin via a resin adhesive or the like.

  In this way, the phosphor 6 can be easily and uniformly unevenly distributed in a layered manner on the one main surface side of the second translucent member 5, and a light emitting device with high emission efficiency with less uneven intensity distribution. It can be easily manufactured.

  Next, the second invention of the present invention will be described. In the second invention of the present invention, no gap is formed between the first translucent member 4 and the second translucent member 5, and the first translucent member 4 The refractive index is the same as that of the first invention except that the refractive index is larger than the refractive index of the second translucent member 5, and a detailed description of the same portion is omitted.

  On the upper surface of the substrate 1, a mounting portion 1a on which the light emitting element 3 is mounted is formed. As shown in FIG. 2, the reflecting member 2 is joined so as to surround the mounting portion 1 a on the upper surface of the base 1, and the inner peripheral surface 2 a is a reflecting surface that reflects light emitted from the light emitting element 3. Yes. A first translucent member 4 is provided on the inner side of the reflective member 2 so as to cover the light emitting element 3, and the first translucent member is provided on the upper surface of the first translucent member 4. 4 and a plate-like second light-transmitting member 5 having a refractive index larger than that of the first light-transmitting member 4 and having phosphors 6 unevenly distributed on the upper surface side. ing.

  Further, the refractive index of the second light transmissive member 5 is larger than that of the first light transmissive member 4. Preferably, the refractive index of the second translucent member 5 is 0.3 or greater than that of the first translucent member 4. As a result, the light emitted downward from the phosphor 6 is likely to be totally reflected at the interface between the upper surface of the first translucent member 4 and the lower surface of the second translucent member 5, which is very efficient. Released outside the light emitting device. Examples of the material of the first translucent member 4 include sol-gel glass and fluorine resin, and examples of the material of the second translucent member 5 include silicone resin and polyimide resin. Can be mentioned.

  The manufacturing method of the 2nd translucent member 5 containing the fluorescent substance 6 produces several translucent members from which the content rate of a fluorescent substance differs, for example, and laminate | stacks it in order from a thing with a high content rate. After forming the second translucent member 5 so that the content of the phosphor 6 gradually decreases from one main surface to the opposite main surface of the second translucent member 5, 6 can be produced by a method such as attaching to the upper surface of the first translucent member 4 such that one main surface side having a high content of 6 is on the upper side. More preferably, after the uncured silicone resin containing the phosphor is vibrated to cause the phosphor 6 to settle on one main surface side and thermally cure, the one main surface side on which the phosphor 6 settles is the upper side. It is good to attach to the upper surface of the 1st translucent member 4 so that it may become.

  By such a manufacturing method, the phosphors 6 are unevenly distributed in the second translucent member 5, but the content of the phosphors 6 gradually decreases from one main surface to the opposite main surface. The phosphor 6 is most unevenly distributed on the surface side.

Thereby, it is possible to effectively prevent the second translucent member 5 from being distorted, and to secure an appropriate gap between the phosphors, which is excited by the light of the light emitting element 3. 6 increases, the fluorescence generated when the phosphor 6 is excited improves. Also, the second translucent member 5 containing the phosphor 6 is attached on the first translucent member 4. For example, after the uncured first light-transmissive member 4 is injected and semi-cured, the second light-transmissive member 5 that has been heat-cured is placed thereon, and the first light-transmissive member 5 is placed thereon. It is formed by further thermosetting the translucent member 4. Or after inject | pouring and hardening the 1st translucent member 4, the 2nd translucent member 5 is mounted on the small amount via the uncured 1st translucent member on it, The uncured first translucent member 4 may be cured.

  In this way, the phosphor can be easily and uniformly unevenly distributed in a layered manner on the one main surface side of the second translucent member 5, and a light emitting device with high emission efficiency with less intensity distribution is easily obtained. Can be produced.

  In addition, about the 1st translucent member 4 and the 2nd translucent member 5, it can select in consideration of a refractive index difference and the transmittance | permeability so that the emitted light intensity of a light-emitting device may become the maximum.

  In the light emitting device of the present invention, the phosphor 6 is unevenly distributed in the form of a layer on the upper surface side of the second translucent member 5, whereby the emission intensity can be improved as follows.

  For example, as a condition that the phosphor 6 is excited and can emit light with the maximum emitted light intensity, when light having an intensity of 100 is incident on the phosphor 6 from the light emitting element 3, the excited phosphor 6 emits light. It is assumed that the maximum intensity of the outgoing light that is wavelength-converted and output is X.

  In addition, since the light emitted from the light emitting element 3 is absorbed by the first light transmissive member 4 and the second light transmissive member 5 before reaching the phosphor 6, the intensity is assumed to be 110 in anticipation of the absorption. As a result, light can be incident on the phosphor 6 at an intensity of 100, and the maximum emitted light intensity X can be emitted from the phosphor 6. Thereafter, the light emitted from the phosphor 6 with the intensity X travels through the second light-transmissive member 5 and travels to a very short path, and then is emitted to the outside. The light of the light emitting element 3 reflected by the light is easily totally reflected at the interface between the gap and the lower surface of the second light transmissive member 5 because there is a gap below the second light transmissive member 5. It can be reflected upward. For this reason, it can be emitted to the outside while maintaining the maximum emitted light intensity X (or a value close thereto).

  However, in the conventional light emitting device, even if the intensity of the light emitting element 13 is determined so that light is emitted from the phosphor with the maximum emitted light intensity, the light emitted from the light emitting element 13 is below the wavelength conversion layer 15. After being emitted from the phosphor existing at the intensity X, an optical loss occurs when passing through the wavelength conversion layer 15, and therefore when emitted outside the light emitting device, it is emitted outside at the maximum output light intensity X. I couldn't.

  In this way, the phosphor existing below the wavelength conversion layer has a loss due to a long path until it is emitted to the outside even if light is emitted with the maximum emitted light intensity. Since the body 6 exists above the second light-transmissive member 5, it is emitted to the outside immediately after being converted to the maximum emitted light intensity, and thus is emitted with strong radiated light intensity and high luminance.

  Here, even if the intensity of the light emitting element 13 in the conventional light emitting device is set to a large value such as 200 to increase the emitted light from the light emitting device, the light that can be emitted by wavelength conversion with the phosphor is already saturated. Therefore, it does not become larger than the maximum emitted light intensity X, and only the light emitted to the outside without being wavelength-converted is increased. For this reason, not only the desired light intensity cannot be improved, but also the amount of unnecessary light that is not wavelength-converted increases, thereby degrading the optical characteristics of the light-emitting device.

  In addition, the light emitting device of the present invention is a circular shape in which one device is installed in a predetermined arrangement, or a plurality of light emitting devices, for example, a lattice shape, a staggered shape, a radial shape, or a plurality of light emitting devices. In addition, a lighting device can be obtained by installing the light emitting device groups in a plurality of concentric shapes so as to have a predetermined arrangement. Thereby, since light emission by recombination of electrons of the light emitting element 3 made of a semiconductor is used, it is possible to achieve lower power consumption and longer life than a lighting device using a conventional discharge, and generate less heat. It can be set as a small illuminating device. As a result, fluctuations in the center wavelength of the light generated from the light emitting element 3 can be suppressed, and light can be emitted with a stable radiant light intensity and radiant light angle (light distribution distribution) over a long period of time. It can be set as the illuminating device by which the color nonuniformity in the surface and the bias of illuminance distribution were suppressed.

  In addition, the light emitting device of the present invention is installed in a predetermined arrangement as a light source, and by installing a reflection jig, an optical lens, a light diffusing plate, etc. optically designed in an arbitrary shape around these light emitting devices, It can be set as the illuminating device which can radiate | emit the light of this light distribution.

  For example, as shown in FIG. 5 and FIG. 6, a plurality of light emitting devices 101 are arranged in a plurality of rows on the light emitting device driving circuit board 102 and optically designed in an arbitrary shape around the light emitting device 101. In the case of an illuminating device in which the reflecting jig 103 is installed, in a plurality of light emitting devices 101 arranged on adjacent rows, an arrangement in which the interval between the adjacent light emitting devices 101 is not the shortest, a so-called staggered pattern It is preferable that That is, when the light emitting devices 101 are arranged in a grid, the glare is strengthened by arranging the light emitting devices 101 as light sources on a straight line, and such a lighting device enters human vision. Thus, discomfort and eye damage are likely to occur, but by forming a staggered pattern, glare is suppressed and discomfort and damage to the eyes of the human eye can be reduced. Furthermore, since the distance between adjacent light emitting devices 101 is increased, thermal interference between adjacent light emitting devices 101 is effectively suppressed, and heat in the light emitting device driving circuit board 102 on which the light emitting devices 101 are mounted is reduced. Clouding is suppressed, and heat is efficiently dissipated to the outside of the light emitting device 101. As a result, it is possible to manufacture a long-life lighting device that has little obstacle to human eyes and has stable optical characteristics over a long period of time.

  Further, the lighting device is a concentric arrangement of a circular or polygonal light emitting device 101 group composed of a plurality of light emitting devices 101 on the light emitting device driving circuit board 102 as shown in the plan view and the cross-sectional view shown in FIGS. In the case of the illuminating device formed in a plurality of groups, it is preferable that the number of the light emitting devices 101 in one circular or polygonal light emitting device 101 group is increased from the central side of the illuminating device to the outer peripheral side. Thereby, it is possible to arrange more light emitting devices 101 while maintaining an appropriate interval between the light emitting devices 101, and it is possible to further improve the illuminance of the lighting device. In addition, the density of the light emitting device 101 in the central portion of the lighting device can be reduced to suppress heat accumulation in the central portion of the light emitting device driving circuit board 102. Therefore, the temperature distribution in the light emitting device driving circuit board 102 becomes uniform, heat is efficiently transmitted to the external electric circuit board and the heat sink on which the lighting device is installed, and the temperature rise of the light emitting device 101 can be suppressed. As a result, the light-emitting device 101 can operate stably over a long period of time, and a long-life lighting device can be manufactured.

  Examples of such lighting devices include general lighting fixtures, chandelier lighting fixtures, residential lighting fixtures, office lighting fixtures, store lighting, display lighting fixtures, street lighting fixtures, used indoors and outdoors. Guide light fixtures and signaling devices, stage and studio lighting fixtures, advertising lights, lighting poles, underwater lighting lights, strobe lights, spotlights, security lights embedded in power poles, emergency lighting fixtures, flashlights, Examples include electronic bulletin boards and the like, backlights for dimmers, automatic flashers, displays and the like, moving image devices, ornaments, illuminated switches, optical sensors, medical lights, in-vehicle lights, and the like.

  It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the scope of the present invention.

It is sectional drawing which shows an example of embodiment of the light-emitting device of 1st invention of this invention. It is sectional drawing which shows the other example of embodiment of the light-emitting device of 1st invention of this invention. It is sectional drawing which shows an example of embodiment of the light-emitting device of 1st invention of this invention. It is sectional drawing which shows the other example of embodiment of the light-emitting device of 1st invention of this invention. It is a top view which shows the other example of embodiment of the illuminating device of this invention. It is sectional drawing of the illuminating device of FIG. It is a top view which shows the other example of embodiment of the illuminating device of this invention. It is sectional drawing of the illuminating device of FIG. It is sectional drawing of the conventional light-emitting device.

Explanation of symbols

1: Base 1a: Placement part 2: Reflecting member 2a: Inner peripheral surface 3: Light emitting element
4: 1st translucent member 5: 2nd translucent member 6: Phosphor

Claims (5)

A base on which a mounting portion for mounting a light emitting element is formed on the upper surface, and an outer peripheral portion of the upper surface of the base are joined so as to surround the mounting portion, and an inner peripheral surface emits light from the light emitting element. A frame-shaped reflecting member that is a reflecting surface that reflects light, a first translucent member that is formed so as to cover the light emitting element inside the reflecting member, and an inner peripheral surface of the frame Alternatively, a plate-like shape is provided on the upper surface so as to cover the first light-transmitting member with a gap between the first light-transmitting member and the phosphor is unevenly distributed in a layered manner on the upper surface side. And a second light-transmitting member. A base on which a mounting portion for mounting a light emitting element is formed on the upper surface, and an outer peripheral portion of the upper surface of the base are joined so as to surround the mounting portion, and an inner peripheral surface emits light from the light emitting element. A frame-shaped reflecting member that is a reflecting surface that reflects light, a first light-transmitting member formed so as to cover the light-emitting element inside the reflecting member, and the first light-transmitting member A plate-like second light-transmitting member provided so as to cover the member, and having a refractive index larger than that of the first light-transmitting member and phosphors being unevenly distributed on the upper surface side. A light emitting device characterized by comprising: 2. The method of manufacturing a light emitting device according to claim 1, wherein the step of bonding the reflecting member to the outer peripheral portion of the upper surface of the base body, the step of mounting the light emitting element on the mounting portion, and the liquid first. And a step of curing the first light-transmitting member after injecting the light-transmitting member inside the reflecting member so as to cover the light-emitting element, and the liquid second light-transmitting light containing the phosphor A step of forming a conductive member into a plate shape, a step of curing the second light transmissive member after the phosphor in the second light transmissive member is settled to one main surface side, and a curing And attaching the second light-transmitting member formed so as to cover the light-emitting element on the upper surface or the inner peripheral surface of the reflecting member so that the one main surface side is on the upper side. A method for manufacturing a light-emitting device. 3. The method of manufacturing a light emitting device according to claim 2, wherein the step of bonding the reflecting member to the outer peripheral portion of the upper surface of the base body, the step of mounting the light emitting element on the mounting portion, and the liquid first. A step of injecting the translucent member to cover the light emitting element inside the reflective member, and the second translucent member having a refractive index larger than that of the first translucent member and including a phosphor. And a step of curing the second light-transmitting member after the phosphor in the second light-transmitting member is allowed to settle to one main surface side. Attaching the second translucent member so as to cover the first translucent member on the upper surface of the first translucent member so that the one main surface side is on the upper side; A method of manufacturing a light emitting device, comprising: An illuminating device, wherein the light emitting device according to claim 1 or 2 is installed in a predetermined arrangement.

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