JP2015043359A - Led light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED light-emitting device including means for effectively suppressing ring-shaped color unevenness occurring due to an optical path length difference in a wavelength conversion member.SOLUTION: In an LED light-emitting device produced by mounting an LED element on a substrate and sealing an upper surface side of the LED element with a wavelength conversion member that absorbs emitted light and performs wavelength conversion, an optical film layer for controlling an optical characteristic of outgoing light is provided for an upper surface of the wavelength conversion member, with the optical film layer being made of a dielectric multilayer film and being formed in a ring shape. The optical film layer formed in the ring shape is constructed to selectively reflect excitation light that is a cause of color unevenness. Thus, application to LED light-emitting devices having various structures of cup type, pancake type, and the like is possible and effective suppression of color unevenness is possible.

Description

  The present invention relates to an LED light-emitting device used for illumination or the like, and more particularly to an LED light-emitting device provided with means for controlling color unevenness of emitted light.

  In recent years, white LEDs having features such as power saving, high efficiency, and long life have been replaced by conventional light sources such as conventional incandescent lamps and fluorescent lamps, and have begun to spread rapidly. There are several types of light emitting devices for white LEDs, but the LED element is coated with a translucent resin containing fluorescent particles, and white light is mixed by the mixed light of LED light and wavelength converted light by fluorescent particles. A light-emitting device that obtains the above is well known.

  In such an LED light emitting device, the emitted light is radiated to the outside, and when the emitted light is viewed from the light emission observation surface side, ring-shaped color unevenness having different color tones is observed at the central portion and the outer portion. is there. The cause of many of these is that there is a difference in the optical path length in the translucent resin between the light emitted from the LED element in the upward direction and the light emitted in the oblique direction, and the light is dispersed in the translucent resin. It is considered that light in an oblique direction has a large amount of converted light components due to a difference in encounter opportunities with fluorescent particles.

  Various proposals have been made as LED light emitting devices having such means for suppressing color unevenness, but here, a semi-spherical type (hereinafter referred to as pancake type) translucency having no reflective frame. Patent Document 1 of an LED light emitting device in which color unevenness is suppressed by forming a resin from a first phosphor layer and a second phosphor layer, and a reflective frame (hereinafter referred to as a cup type), and the interior Patent Document 2 of an LED light-emitting device in which color unevenness is suppressed by disposing a plate-like phosphor layer via an encapsulating layer and a heat insulating layer will be described as a conventional example.

  Here, the pancake-type LED light-emitting device disclosed in FIG. 1 of Patent Document 1 is shown in FIG. 14, the cup-type LED light-emitting device disclosed in FIG. 5 of Patent Document 2 is shown in FIG. Hereinafter, those conventional examples will be described. For ease of understanding, the names of parts are aligned with the present application within a range not departing from the spirit of the invention, and the drawings are also simplified.

  First, the pancake-type LED light emission measure 200 of Patent Document 1 will be described with reference to FIG. FIG. 14A shows the state of color unevenness on the irradiated surface 201 of the emitted light of the LED light emitting device 200, and FIG. First, in FIG. 14B, the LED element 102 is mounted on the wiring board 103, and the electrodes on the upper surface of the element are electrically connected to the wiring pattern provided on the wiring board 103 by bonding wires 131. The phosphor layer 104 is a pan that covers the first phosphor layer 141 covering the periphery of the LED element 102 and the LED element 102 and the first phosphor layer 141 so as to be substantially the same height as the upper surface of the LED element 102. And a cake-type phosphor layer 142. Here, the phosphor concentration of the second phosphor layer 142 is configured to be higher than the phosphor concentration of the first phosphor layer 141. Thereby, the emitted light of the LED element 102 has a small amount of conversion component emitted in the lateral direction of the first phosphor layer 141 and a large amount of conversion component emitted in the lateral direction from the second phosphor layer 142. Since light is mixed appropriately (C region light), color unevenness in the lateral direction is unlikely to occur.

  Next, the cup-type LED light emitting device 300 of Patent Document 2 will be described with reference to FIG. FIG. 15A shows the state of color unevenness on the irradiation surface 301 of the emitted light of the LED light emitting device 300, and FIG. 15B shows the cross-sectional configuration of the LED light emitting device 300. FIG. First, in FIG. 15B, the LED element 312 is mounted on the wiring pattern 311-1 on the wiring board 311 provided with the reflection frame body 318 by flip chip or the like, and the electrode of the element and the wiring pattern are electrically connected. It is connected. The LED element 312 is sealed inside the reflective frame 318 by a translucent resin (encapsulation layer) 315. A phosphor layer 313 is disposed via a heat insulating layer (air layer) 316 disposed on the upper surface thereof. A heat dissipation layer 314 is disposed on the upper surface of the phosphor layer 313. Thereby, the excitation heat 313-2h generated when the phosphor 313-2 mixed in the phosphor layer 313 is excited by the emitted light of the LED element 312 is converted into the heat 314h in the air via the heat dissipation layer 314. It becomes heat dissipation. Further, since the radiant heat from the LED element 312 is reduced by the heat insulating layer 316, deterioration of the phosphor layer 313 can be reduced. In addition, due to the thin plate-like effect of the phosphor layer 313, the difference in optical path length between light in the upward direction (A area light) and oblique light (B area light) is small, and color unevenness is suppressed. Is done.

JP 2012-248553 A (FIG. 1) Japanese Patent No. 5100744 (FIG. 5)

  Here, in FIG. 14B, in the region of the radiated light A of the conventional LED light emitting device 200, the concentration of the phosphor is assumed assuming the distance s1 through which the radiant light P1 in the upward direction passes through the phosphor layer 142. It is set so that white light can be obtained by appropriately mixing blue light and yellow light. Thereby, the conversion component light by a fluorescent substance is the radiation light of moderate density (the density of arrow Py is moderate). In the region C, light having a small amount of conversion component passing through the phosphor layer 141 having a low concentration and light having a large amount of conversion component passing through the phosphor layer 142 having a high concentration are appropriately mixed so that the conversion component is moderate. The density radiation light (the density of the arrow Py is moderate).

  However, in the region B, the obliquely emitted light P2 is transmitted through the phosphor layer 142 having a high concentration, but the distance s2 is longer than the transmission distance s1 of the emitted light P1. Therefore, it is radiant light (the density of arrow Py is high) with many conversion components. As a result, there is a concern that the density of the converted component light Py becomes high in the region B sandwiched between A and C as shown by the irradiation surface 201 in FIG. In addition, in manufacturing, it is difficult to manage the process if the height of the resin serving as the first phosphor layer is controlled to be substantially the same as the upper surface of the LED element. Also, the management of different concentrations of the two phosphor layers tends to vary. As a result, there is a concern that the man-hour increases and the manufacturing cost increases.

  Next, in FIG.15 (b), the fluorescent substance layer 313 of the conventional LED light-emitting device 300 is thin plate shape, and since it is arrange | positioned in the position away from the LED element, it passes through the fluorescent substance layer 313. The difference in optical path length is considerably reduced between the transmission distance s1 of the radiation light P1 in the upward direction and the transmission distance s2 of the radiation light P2 in the oblique direction. However, since the optical path length difference (s2−s1) is not completely eliminated, the B component tends to have more converted component light Py (the density of the arrow Py is higher) than the A region. As shown in (a), there is a concern that color unevenness occurs in the area A and the area B. In addition, since the heat insulating layer 316 is provided below the phosphor layer 313, it is difficult to radiate the excitation heat 313-2h generated in the phosphor layer 313 directly from the encapsulating layer 315 to the substrate side. As a result, it is necessary to dissipate heat by providing the heat dissipation layer 314 on the upper surface side of the phosphor layer 313. For this reason, there is a concern that the heat radiation of the excitation heat of the phosphor layer 313 cannot be sufficiently performed.

(Object of invention)
Therefore, an object of the present invention is to solve the above-mentioned problems, and can be applied to LED light-emitting devices having different structures such as pancake type and cup type, have good heat dissipation, high productivity, and Another object of the present invention is to provide an LED light emitting device provided with means for effectively suppressing color unevenness.

In order to achieve the above object, the configuration of the LED light emitting device in the present invention is as follows.
In the LED light emitting device formed by mounting the LED element on the substrate and sealing the upper surface side of the LED element with a wavelength conversion member that absorbs emitted light and converts the wavelength,
An optical film layer for controlling the optical characteristics of the emitted light is provided on the upper surface of the wavelength conversion member, and the optical film layer is characterized in that a dielectric multilayer film is formed in a ring shape.

  According to the above-described configuration, the ring-shaped dielectric multi-layer corresponding to the ring-shaped color unevenness generated due to the optical path length difference in the wavelength conversion member of the light emission directed directly upward and the light emission directed toward the side surface. Since the optical film layer made of a film is provided to control the emitted light, color unevenness can be effectively and easily suppressed. Further, since the LED element is sealed on the substrate with the wavelength conversion member, it is easy to radiate the LED element and the excitation heat of the wavelength conversion member. Moreover, since the wavelength conversion member of several density | concentration is not required, manufacture is easy.

  Further, the optical film layer formed in a ring shape may be formed by concentrically forming a plurality of dielectric multilayer films having different optical characteristics.

  Accordingly, since the optical film layer composed of a plurality of ring-shaped dielectric multilayer films having different optical characteristics is provided in response to the chromaticity difference of the ring-shaped color unevenness that occurs, the stepwise color unevenness It becomes possible to suppress color unevenness more effectively.

  The LED element is a blue LED element, the wavelength conversion member is a fluorescent resin containing yellow fluorescent particles, and the dielectric multilayer film preferably has an optical characteristic of reflecting yellow light corresponding to the color unevenness of the emitted light. . Thereby, in the LED light emitting device composed of the blue LED and the yellow fluorescent resin, the reflectance or the reflection wavelength range corresponding to the generated color unevenness can be set and the color unevenness can be effectively suppressed.

  The LED element is a blue LED element, the wavelength conversion member is a fluorescent resin containing yellow fluorescent particles and red fluorescent particles, and the dielectric multilayer film reflects yellow light and red light corresponding to the color unevenness of the emitted light. It may have optical properties. This effectively suppresses color unevenness by setting a reflectance or a reflection wavelength range corresponding to the color unevenness that occurs in the configuration of an LED light emitting device that includes yellow fluorescent particles and red fluorescent particles and has improved color rendering. can do.

  The LED element is a blue LED element, the wavelength conversion member is a fluorescent resin containing green fluorescent particles and red fluorescent particles, and the dielectric multilayer film reflects green light and red light corresponding to the color unevenness of the emitted light. It may have optical properties. This effectively suppresses color unevenness by setting a reflectance or a reflection wavelength range corresponding to the color unevenness that occurs in the configuration of an LED light emitting device that includes green fluorescent particles and red fluorescent particles and has improved color rendering. can do.

  A reflective frame is provided on the upper surface of the substrate, and the fluorescent resin is preferably filled in the reflective frame. As a result, in the cup-type LED light emitting device in which the LED frame mounted on the substrate is filled and sealed with the fluorescent resin, the reflectance or the reflection wavelength range corresponding to the generated color unevenness is set. Thus, color unevenness can be effectively suppressed. Further, heat radiation from the reflection frame is added, and heat radiation from the LED element and excitation heat from the wavelength conversion member are facilitated.

  According to the configuration of the present invention, an optical film layer composed of a ring-shaped dielectric multilayer film is provided in response to the ring-shaped color unevenness that occurs, and the reflectance or reflection wavelength of the optical film layer depends on the chromaticity difference. Since the area can be set, color unevenness can be effectively suppressed. Further, since the optical film layer can be formed on a flat surface or a curved surface, it can be applied to both pancake type and cup type LED light emitting devices. Further, since the LED element can be sealed on the substrate with one concentration of fluorescent resin, the manufacturing is easy. Moreover, it is easy to release the excitation heat of the phosphor through the fluorescent resin. As a result, it is possible to provide an LED light emitting device having good heat dissipation, high productivity, a wide range of application to structures, and means capable of effectively suppressing color unevenness.

It is sectional drawing and irradiation figure of the LED light-emitting device of 1st Embodiment of Example 1. FIG. It is a figure which shows the reflective characteristic of the dielectric multilayer film of 1st Embodiment of Example 1. FIG. 1 is a principle diagram of a dielectric multilayer film according to a first embodiment of Example 1. FIG. 3 is a perspective view showing a film layer of the first embodiment of Example 1. FIG. It is sectional drawing and irradiation figure of the LED light-emitting device of 2nd Embodiment of Example 1. FIG. It is a figure which shows the reflective characteristic of the dielectric multilayer film of 2nd Embodiment of Example 1. FIG. It is a perspective view which shows the film | membrane layer of 2nd Embodiment of Example 1. FIG. It is a figure which shows the reflective characteristic of the dielectric multilayer film of 3rd Embodiment of Example 1. FIG. It is a figure which shows the reflective characteristic of the dielectric multilayer film of 4th Embodiment of Example 1. FIG. It is sectional drawing and irradiation figure of the LED light-emitting device of 1st Embodiment of Example 2. FIG. 6 is a perspective view showing a film layer according to a first embodiment of Example 2. FIG. It is sectional drawing and irradiation figure of the LED light-emitting device of 2nd Embodiment of Example 2. FIG. 6 is a perspective view showing a film layer according to a second embodiment of Example 2. FIG. It is sectional drawing and irradiation figure which show the conventional LED light-emitting device 200. It is sectional drawing and irradiation figure which show the conventional LED light-emitting device 300.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiment described below exemplifies an LED light emitting device for embodying the idea of the present invention, and the present invention is not limited to the following configuration. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments are merely illustrative examples and not intended to limit the scope of the present invention unless otherwise specified. Absent. In addition, the size, positional relationship, optical path, and the like of the members shown in each drawing may be exaggerated for clarity of explanation, and in particular, explanation of light emission of LED and excitation light of fluorescent particles is simplified with arrows and the like. Is explained. In the following description, the same parts and the same components are denoted by the same names and reference numerals, and detailed description may be omitted as appropriate.

[Features of each embodiment]
The LED light-emitting device of the present invention comprises an LED element mounted on a substrate part and a wavelength conversion member (hereinafter referred to as a fluorescent resin) containing fluorescent particles for sealing the LED element, and a dielectric multilayer film on the upper surface of the fluorescent resin. The present invention relates to an improvement in suppression of color unevenness generated in the irradiated light by providing an optical film layer made of According to the structure using the optical film layer of the present invention, ring-shaped color unevenness caused by the difference in the optical path length in the fluorescent resin between the light emission directed upward and the light emission directed toward the side surface is effectively suppressed. can do. Here, Example 1 relates to an improvement of a cup-type LED light emitting device that includes a reflective frame on a substrate, mounts the LED element therein, and seals the LED element with a fluorescent resin. The present invention relates to an improvement of a pancake-type LED light emitting device which is not provided with a reflection frame and in which an LED element is sealed with a fluorescent resin. Hereinafter, Example 1 is demonstrated using FIGS. 1-9, and Example 2 is demonstrated using FIGS. 10-13.

  Hereinafter, a cup-type LED light-emitting device of Example 1 according to the present invention will be described. Here, there are four embodiments in Example 1, the first embodiment is shown in FIGS. 1 to 4, the second embodiment is shown in FIGS. 5 to 7, and the third embodiment is shown in FIG. 8 and FIG. 9 shows a fourth embodiment.

[Description of First Embodiment of Example 1: FIGS. 1 to 4]
Hereinafter, the LED light emitting device 50 according to the first embodiment of Example 1 will be described with reference to FIGS. FIG. 1A is an irradiation diagram showing the color unevenness state on the irradiated surface of the LED light emitting device 50, and FIG. 1B shows a cross-sectional configuration of the LED light emitting device 50. FIG. 2 shows the reflection characteristics of the optical film layer, and the light emission spectrum of the LED light emitting device 50 is superimposed and displayed. The horizontal axis of the graph indicates the wavelength (nm), the left vertical axis indicates the reflectance (%) of the optical film layer, and the right vertical axis indicates the relative emission intensity of the emission spectrum. Here, how to read the graph is the same in other embodiments described later. FIG. 3 is a principle diagram concerning the film layer configuration and reflection of the dielectric multilayer film, and is common to other embodiments described later. FIG. 4 is a perspective view of an optical film layer formed in a ring shape.

[Description of configuration: FIG. 1]
First, the configuration of the LED light emitting device 50 will be described with reference to FIG. In FIG. 1B, the blue LED element 1 is provided with an electrode on one surface, and is flip-chip mounted on the wiring electrode 5 and the wiring electrode 6 provided on the substrate 4 by two bumps 3, respectively. Electrically connected. The wiring electrode 5 and the wiring electrode 6 are formed on the surface of the substrate 4, and one surface forms a wiring pattern for mounting the blue LED element 1, and the other surface is an LED light emitting device or the like (illustrated). None) is formed as a wiring pattern.

  In addition, although the mounting structure of the LED element is flip-chip bonding in the embodiment, a mounting method by wire connection in which the electrode forming surface side of the LED element is the main light extraction surface can be adopted, and is appropriately adjusted to the structure of the element. Connection means can be employed. Further, the substrate 4 is formed with a wiring pattern connected to at least the electrode of the LED element, and the substrate material is preferably ceramic such as alumina with good heat dissipation characteristics, and the light emission from the LED element is in the light extraction direction. It is preferable that at least the surface thereof is made of a highly reflective material so that it can be effectively reflected.

  Next, the reflection frame 7 is fixed on the substrate 4 and filled with a fluorescent resin 8 containing fluorescent particles to seal the mounted blue LED element 1. The reflective frame 7 is made of a resin containing a material that reflects light as a constituent material, and is formed on the substrate 4 by a molding machine. Further, the inner surface is provided with a taper so that the emitted light of the blue LED element 1 can be reflected in the extraction direction.

  Here, the fluorescent resin 8 contains dispersed yellow fluorescent particles that convert the emission wavelength of the blue LED element 1 and emit yellow light Py. When the fluorescent resin 8 is filled in the reflection frame 7, the blue light emitted from the LED element 1 is radiated in each direction, passes through the fluorescent resin 8, and is emitted into the air without encountering the fluorescent particles. Some of them encounter fluorescent particles and wavelength-convert them to become yellow light Py, which is emitted into the air.

  Next, an optical film layer 10 made of a ring-shaped dielectric multilayer film is provided on the upper surface of the fluorescent resin 8. As shown in FIG. 4, the ring-shaped optical film layer 10 is formed so as to cover the upper surface of the fluorescent resin 8 with a width t <b> 1 according to the outer shape of the reflection frame 7 and the filling shape of the fluorescent resin 8. The optical characteristics and detailed shape of the optical film layer 10 will be described later.

[Explanation of emission spectrum: FIG. 2]
Next, the emission spectrum 21 of the LED light emitting device 50 will be described with reference to FIG. The emission spectrum 21 (shown by a broken line) shown in FIG. 2 is 2 of blue light B (peak is about 450 nm) emitted from the blue LED element 1 and yellow light Y (peak is about 560 nm) excited by yellow fluorescent particles. It consists of light with two peaks. Thereby, the blue light B and the yellow light Y are mixed appropriately and white light is obtained.

[Description of Optical Film Layer: FIGS. 1, 2, 3, and 4]
Next, details of the optical film layer 10 made of a dielectric multilayer film will be described with reference to FIG. FIG. 3 is an EE cross-sectional view of the upper surface portion of the fluorescent resin 8 in the LED light emitting device 50 shown in FIG. In FIG. 3, a film of a quarter wavelength thick low refractive index material 13 made of a dielectric is coated on the upper surface of the fluorescent resin 8, and a quarter wavelength thick high refractive index material 14 made of a dielectric is further formed thereon. The film is coated. By laminating a plurality of these two layers as a pair, an optical film layer 10 having a reflection characteristic obtained by additively overlapping the reflected wavefront from the boundary surface of each layer with respect to the incident light can be configured. .

  Further, the optical film layer 10 changes the refractive index ratio between the dielectric film 13 having a low refractive index and the dielectric film 14 having a high refractive index, or has a refractive index that is the same as that of the dielectric film 13 having a low refractive index. By changing the film thickness of the high dielectric film 14, the reflectance can be changed. In addition, the reflectance can be changed for light in a specific wavelength range.

  Next, the optical characteristics of the optical film layer 10 employed in the present embodiment will be described with reference to FIG. The reflection characteristic 22 (shown by a solid line) of the optical film layer 10 shown in FIG. 2 has a ra% reflectance for yellow light in the range of about 500 nm to 640 nm, and the reflectance is zero in other wavelength regions. The characteristics are as follows. In addition, the reflectance and the reflection wavelength region can be changed by changing the dielectric film layer configuration as described above, and the film layer width t1 (FIG. 1) can also be changed. As a result, by adjusting the reflectance, the reflection wavelength region, and the film layer width of the optical film layer 10 in accordance with the chromaticity difference of color unevenness and the ring width of color unevenness, an extra yellow color that causes color unevenness It becomes possible to return the light Py into the fluorescent resin 8 by reflection, and the density of the yellow light Py in the oblique direction can be made equal to the density of the yellow light Py in the upward direction as shown in FIG. In the irradiation surface 51 of FIG. 1A, color unevenness is suppressed.

  Next, the shape of the optical film layer will be described with reference to FIG. In the LED light emitting device 50, the shape of the optical film layer 10 can be changed according to the shape of the reflection frame 7. For example, as shown in FIG. 4A, when the inner wall of the reflection frame 7 has a round cup shape, an optical film layer 10a having a round inner diameter in accordance with the round fluorescent resin 8 (LED light emission). Apparatus 50A). As shown in FIG. 4B, when the inner wall of the reflection frame 7 has a square cup shape, an optical film layer 10b (LED light emitting device 50B) having a square inner side in accordance with the square fluorescent resin 8 is used. Also good.

  The optical film layer made of these dielectrics can be formed by a method such as vacuum vapor deposition or sputtering, and an optical film layer having predetermined characteristics is formed by laminating a predetermined film thickness using a predetermined material. Can be formed. Moreover, it can form in a predetermined shape and width | variety using a masking technique. Further, the reflection characteristics of the optical film layer, the principle of the dielectric multilayer film, and the shape of the optical film layer described in FIGS. 2, 3, and 4 are the same in other embodiments described later, and are duplicated figures. Or some explanation is omitted.

[Description of light emission operation: FIGS. 1 and 2]
Next, the light emission operation of the LED light emitting device 50 will be described with reference to FIGS. 1 and 2. First, in FIG. 1B, when a voltage is applied from the outside to the wiring electrode 5 and the wiring electrode 6 disposed on the substrate 4 of the LED light emitting device 50 (not shown), the blue LED element 1 A voltage is applied to the electrode to emit blue light. Of this LED light, the blue light P1 heading upward is transmitted through the fluorescent resin 8 at a distance s1 and radiated upward. On the other hand, the blue light P2 traveling in the oblique direction is transmitted through the fluorescent resin 8 at a distance s2, and is emitted in the oblique direction.

  Here, since the yellow fluorescent particles are uniformly dispersed in the fluorescent resin 8, the transmission distance difference s2-s1 is a difference in the chance of encountering the yellow fluorescent particles, and the blue light P2 traveling in the oblique direction is the yellow fluorescent particles. And more opportunities to encounter. For this reason, the density of the yellow light Py excited by the blue light P1 is increased. As a result, when blue light and yellow light Py are mixed in the irradiation range of the LED light emitting device 50, white light having a high density of yellow light Py is obtained in the oblique direction as compared with the directly upward direction, and as a result, the optical film layer In the state where there is no 10, there is a ring-shaped color unevenness with a strong yellowishness on the irradiated surface. (As described above, the density of the region B in the oblique direction increases as indicated by the arrow indicating the density of the yellow light Py emitted from the conventional LED light emitting device 300. See FIG. 15B).

  Here, in the present embodiment, the ring-shaped optical film layer 10 is disposed on the upper surface of the fluorescent resin 8 at a portion where the emitted light in the oblique direction is emitted, and a part of the yellow light Py is reflected into the fluorescent resin 8. As a result, the density of yellow light Py can be reduced. In addition, since the reflectance, reflection wavelength region, and film layer width of the optical film layer 10 can be adjusted, the density of the yellow light Py can be adjusted with respect to the radiation light in the oblique direction.

  Next, the operation of the optical film layer 10 disposed on the upper surface of the fluorescent resin 8 will be described with reference to FIG. The optical film layer 10 is formed in a predetermined configuration based on the principle of the optical film layer composed of the above-described dielectric multilayer film, and reflects ra% of yellow light (yellow light in the range of about 500 nm to 640 nm). It is a characteristic to do. As a result, ra% of the yellow light Py that is about to pass through the optical film layer 10 is reflected and returned to the fluorescent resin 8. The remaining (100-ra)% yellow light Py passes through the optical film layer 10 and is emitted to the outside. Further, since the reflectance of the optical film layer 10 with respect to blue light is zero%, all blue light can be transmitted. As a result, the obliquely emitted light has a lower density of the yellow light Py and can be at the same level as the density of the yellow light Py emitted in the upward direction. As a result, the density of the yellow light Py is uniform in the entire radiation region, color unevenness is suppressed on the irradiated surface 51 (FIG. 1A), and uniform white light can be obtained.

[Effects of First Embodiment of Example 1]
According to 1st Embodiment of Example 1 demonstrated above, the effect shown next is acquired.
[Effect 1]
In a cup-type LED light-emitting device with a reflective frame and directivity, a ring-shaped optical film layer consisting of a dielectric multilayer film is provided on the top surface of the fluorescent resin, and its reflection characteristics and shape are compatible with color unevenness situations Therefore, color unevenness can be effectively suppressed by combining them.
[Effect 2]
The wavelength conversion member that seals the LED element in the reflection frame has high productivity because the concentration of the fluorescent particles contained therein can be easily controlled by using a single concentration of fluorescent resin.
[Effect 3]
By adopting a configuration (cup type) in which the LED element is filled and sealed with a fluorescent resin in the reflective frame provided on the substrate, excitation heat generated from the fluorescent particles can be efficiently transferred to the substrate side through the fluorescent resin or the reflective frame. It can dissipate heat.
Thereby, in a cup-type LED light-emitting device, it is possible to provide an LED light-emitting device that is excellent in the heat dissipation effect of excitation heat, has high productivity, and includes means for effectively suppressing color unevenness.

  The shape of the reflection frame is not limited to the embodiment such as the depth, area, and shape of the slope. For example, the fluorescent resin filling portion may be round or square. . Moreover, although this embodiment demonstrated the case where there was one LED element, it is not limited to this, It can apply also to the light-emitting device which packaged the some LED element of the array form.

[Second Embodiment of Example 1: FIGS. 5 to 7]
Next, the LED light emitting device 55 according to the second embodiment of Example 1 will be described with reference to FIGS. FIG. 5A is an irradiation diagram showing the color unevenness state on the irradiated surface of the LED light emitting device 55, and FIG. 5B shows a cross-sectional configuration of the LED light emitting device 55. FIG. 6 shows the reflection characteristics of the optical film layer, and FIG. 7 shows a perspective view of the optical film layer. The LED light emitting device 55 is different from the first embodiment in that the second optical film layer 11 is provided concentrically in addition to the first optical film layer 10. Since it is the same as that of 1 embodiment, the same number is attached | subjected to the same element and the overlapping description is partially abbreviate | omitted.

[Description of configuration: FIG. 5]
First, the structure of the LED light-emitting device 55 of 2nd Embodiment is demonstrated using FIG.5 (b). In FIG. 5B, the LED light emitting device 55 has the same basic configuration as the LED light emitting device 50 except for the optical film layer, and the second optical film layer 11 is concentrically inside the first optical film layer 10. Is provided. The first optical film layer 10 and the second optical film layer 11 have different reflection characteristics and film layer widths, respectively, so that color unevenness can be suppressed in stages. Here, the film layer width of the first optical film layer 10 is t2, and the film layer width of the second optical film layer 11 is t3.

[Description of Optical Film Layer: FIGS. 6 and 7]
Next, the reflection characteristics of the optical film layer 10 and the optical film layer 11 will be described with reference to FIG. In FIG. 6, the reflection characteristic 22 of the optical film layer 10 has a reflectance of rb%, and the reflection characteristic 23 of the optical film layer 11 has a reflectance of rc%. The reflection wavelength range is a wavelength range that substantially covers the yellow light Y as in the first embodiment. Thereby, the reflectance of the two optical film layers, the reflection wavelength region, and the film layer width can be changed to match the color unevenness.

  Further, in the LED light emitting device 55, the shapes of the optical film layer 10 and the optical film layer 11 can be changed according to the shape of the reflection frame 7. For example, as shown in FIG. 7A, when the inner wall of the reflection frame 7 has a circular cup shape, the optical film layer 10a is rectangular on the outside and circular on the inside, and the optical film is circular on both the outside and the inside. It can be set as the structure (LED light-emitting device 55A) by the combination of the film layer 11a. Further, as shown in FIG. 7B, when the inner wall of the reflection frame 7 has a square cup shape, a configuration (LED light emission) by a combination of the rectangular optical film layer 10b and the rectangular optical film layer 11b. Device 55A).

[Description of light emitting operation: FIGS. 5 and 6]
Next, the operation of the LED light emitting device 55 will be described with reference to FIGS. 5 and 6. First, in FIG. 5B, the blue light P1 that passes through the fluorescent resin 8 and goes directly upward is transmitted through the fluorescent resin 8 at a distance s1 and is emitted directly upward. On the other hand, the blue light P2 radiated in the oblique direction has a distance of passing through the fluorescent resin 8 as s2, and s1 <s2 with respect to the passing distance s1 in the directly upward direction, so that there are many opportunities to encounter yellow fluorescent particles. The density of the excited yellow light Py is increased.

  Further, the blue light P3 traveling in the middle between the directly upward direction and the diagonal direction has a distance of passing through the fluorescent resin 8 as s3, and each distance has a relationship of s1 <s2 <s3. As a result, the density of the yellow light Py becomes higher in the order of s1 <s2 <s3, and color unevenness such as a strong yellowishness on the outer side on the irradiation surface, a slight yellowishness on the inner side, and white in the central portion occurs. Here, in the present embodiment, the optical film layer 10 and the optical film layer 11 having different ring-shaped optical characteristics are disposed on the upper surface of the fluorescent resin 8 in the portions that emit the obliquely emitted radiation light s2 and s3, respectively. Since part of the yellow light Py is reflected into the fluorescent resin 8, the density of the yellow light Py can be reduced stepwise. Further, since the reflectance, reflection wavelength region, and film layer width of the optical film layer 10 and the optical film layer 11 can be adjusted, the density of the yellow light Py is adjusted stepwise with respect to the obliquely radiated light. can do. As a result, the density of the yellow light Py is uniform in the entire radiation region, color unevenness is suppressed on the irradiation surface 56 (FIG. 5A), and uniform white light can be obtained.

[Effect of Second Embodiment of Example 1]
According to 2nd Embodiment of Example 1 demonstrated above, the effect shown next is acquired.
[Effect 1]
In a cup-type LED light-emitting device having a reflective frame and having directivity, two ring-shaped optical film layers made of a dielectric multilayer film are provided concentrically on the top surface of a fluorescent resin, and their optical characteristics and shape are determined. Color unevenness can be more effectively suppressed by adjusting in steps corresponding to the color unevenness situation. In the present embodiment, two optical film layers are provided, but the present invention is not limited to this, and may be three or more.

[Description of the third embodiment of the first embodiment: FIG. 8]
Next, a third embodiment of Example 1 will be described with reference to FIG. Here, since the figure which shows the structure of 3rd Embodiment is the same as that of FIG. 5 in 2nd Embodiment, a structure figure is abbreviate | omitted and it is set as the LED light-emitting device 57. FIG. The LED light emitting device 57 of the third embodiment is different from the second embodiment in that the fluorescent resin 8 contains two types of fluorescent particles and two optical film layers are provided in order to improve color rendering. It is a point corresponding to it. Since other configurations and operations are the same as those of the second embodiment, the same elements are denoted by the same reference numerals or symbols, and a part of overlapping description is omitted.

  Here, in the LED light emitting device 57, yellow fluorescent particles and red fluorescent particles are mixed in the fluorescent resin 8, and the emission spectrum of the LED light emitting device 57 will be described with reference to FIG. In FIG. 8, the emission spectrum 24 (indicated by a broken line) includes blue light B (peak is about 450 nm) emitted from the blue LED element 1 and yellow light Y (peak is about 560 nm) excited by yellow fluorescent particles. It is composed of light having three peaks of red light R (peak is about 650 nm) excited by red fluorescent particles. Thereby, the blue light B, the yellow light Y, and the red light R are mixed appropriately and white light with high color rendering properties is obtained.

  Next, the reflection characteristics of the two optical film layers will be described. The reflectance of the first optical film layer 10 is rd%, and the reflectance of the second optical film layer 11 is re%. Further, both of the reflection wavelength regions are regions including yellow light Y and red light R. With the above configuration, in the LED light emitting device 57 in which yellow fluorescent particles and red fluorescent particles are mixed in the fluorescent resin 8 to improve color rendering, stepwise by providing two different optical film layers corresponding to color unevenness. The reflection characteristics and the film layer width are combined, and yellow light Y and part of red light R are reflected to suppress color unevenness.

[Effects of Third Embodiment of Example 1]
According to 3rd Embodiment of Example 1 demonstrated above, the effect shown next is acquired.
[Effect 1]
In a cup-type LED light-emitting device having improved color rendering properties containing yellow fluorescent particles and red fluorescent particles, color unevenness can be more effectively suppressed by providing two optical film layers.
In this embodiment, two optical film layers are used. However, one optical film layer may be used.

[Description of Fourth Embodiment of Example 1: FIG. 9]
Next, the 4th light-emitting device 58 of Example 1 is demonstrated using FIG. Here, since the figure which shows the structure of 4th Embodiment is the same as that of FIG. 5 in 2nd Embodiment, a structure figure is abbreviate | omitted and it is set as the LED light-emitting device 58. FIG. The LED light emitting device 58 of the fourth embodiment is different from the second embodiment in that the fluorescent resin 8 contains two types of fluorescent particles in order to improve color rendering, and two optical film layers are provided. It is a point corresponding to it. Since other configurations and operations are the same as those of the second embodiment, the same elements are denoted by the same reference numerals or symbols, and a part of overlapping description is omitted.

  Here, in the LED light-emitting device 58, green fluorescent particles and red fluorescent particles are mixed in the fluorescent resin 8, and the emission spectrum of the LED light-emitting device 58 will be described with reference to FIG. An emission spectrum 27 (indicated by a broken line) is generated by blue light B (peak is about 450 nm) emitted from the blue LED element 1, green light G (peak is about 520 nm) excited by green fluorescent particles, and red fluorescent particles. It is composed of light having three peaks of red light R to be excited (peak is about 650 nm). Thereby, the blue light B, the green light G, and the red light R are mixed appropriately, and white light with high color rendering properties is obtained.

Next, the reflection characteristics of the two optical film layers will be described with reference to FIG. The reflectance of the first optical film layer 10 is rf%, and the reflectance of the second optical film layer 11 is rg%. Further, both of the reflection wavelength regions are regions including the green light G and the red light R. With the above configuration, in the LED light-emitting device 58 in which green fluorescent particles and red fluorescent particles are mixed in the fluorescent resin 8 to improve color rendering, by providing two different optical film layers corresponding to the color unevenness, stepwise. The reflection characteristics and the film layer width are combined with each other, and part of the green light G and the red light R is reflected to suppress color unevenness.
The effect of the optical film layer in the third and fourth embodiments with improved color rendering is also effective in a pancake-type LED light emitting device described later.

  Next, a pancake-type LED light emitting device of Example 2 according to the present invention will be described. Here, Example 2 has two embodiments. The first embodiment is shown in FIGS. 10 and 11, and the second embodiment is shown in FIGS. 12 and 13.

[Description of First Embodiment of Example 2: FIGS. 10 and 11]
First, the LED light emitting device 60 according to the first embodiment of Example 2 will be described with reference to FIGS. 10 and 11. FIG. 10A is an irradiation diagram illustrating the color unevenness state on the irradiation surface of the emitted light of the LED light emitting device 60, and FIG. 10B illustrates a cross-sectional configuration of the LED light emitting device 60. FIG. 11 is a perspective view showing a state in which the optical film layer is provided on the curved surface of the fluorescent resin 8 of the LED light emitting device 60 of the optical film layer. The LED light emitting device 60 is different from the first embodiment of Example 1 described above only in that the LED light emitting device 60 is a pancake type LED light emitting device that does not have a reflecting frame, and a basic structure in which a ring-shaped optical film layer is provided. Since the general configuration is the same as that of the first embodiment of the first embodiment, the same elements are denoted by the same reference numerals or the same reference numerals, and a part of overlapping description is omitted.

[Description of Configuration: FIG. 10]
First, in FIG. 10, the configuration of the pancake type LED light emitting device 60 is not provided with a reflection frame body and the fluorescent resin 8 is substantially hemispherical as compared with the cup type LED light emitting device of Example 1. The difference is that it is a wide-angle light distribution type that can emit light in the lateral direction. The optical film layer 10 shown in FIG. 10B is provided on the curved surface of the fluorescent resin 8, and when shown in a perspective view, it becomes a three-dimensional optical film layer as shown in FIG. However, the optical film layer can be easily formed on these curved surfaces by a method such as vacuum vapor deposition or sputtering as in the case of forming on a flat surface.

[Description of light emission operation: FIG. 10]
Here, also in the pancake-type LED light emitting device 60, the color unevenness can be suppressed by the same operation as in the above-described embodiments.

[Effect of First Embodiment of Example 2]
As mentioned above, according to 1st Embodiment of Example 2 demonstrated, the effect shown next is acquired.
[Effect 1]
In a pancake-type LED light-emitting device capable of wide-angle light distribution, a ring-shaped optical film layer is provided on the curved surface of the fluorescent resin, and the reflection characteristics and film layer width are matched to correspond to the color unevenness situation, thereby causing uneven color. Can be suppressed.

[Explanation of Second Embodiment of Example 2: FIGS. 12 and 13]
Next, the LED light emitting device 65 according to the second embodiment of Example 2 will be described with reference to FIGS. FIG. 12A is an irradiation diagram showing the color unevenness state on the irradiated surface of the LED light emitting device 65, and FIG. 12B shows a cross-sectional configuration of the LED light emitting device 65. FIG. 13 is a perspective view showing a state in which the optical film layer is provided on the curved surface of the fluorescent resin 8 of the LED light emitting device 65 of the optical film layer. The LED light emitting device 65 is different from the first embodiment of Example 2 described above in that two ring-shaped optical film layers are provided on the curved surface of the fluorescent resin 8 of the pancake type LED light emitting device. Since the basic configuration for providing the ring-shaped optical film layer is the same as that of the second embodiment of the first embodiment, the same elements are denoted by the same reference numerals or the same reference numerals, and redundant description is omitted.

The pancake-type LED light-emitting device 65 can obtain the same effects as those of the second embodiment of Example 1 in a wide-angle light distribution type configuration, and can more effectively suppress color unevenness.
In addition, although 1st Embodiment or 2nd Embodiment of Example 2 demonstrated the improvement of suppression of the color nonuniformity in a pancake type light-emitting device, it is not limited to this, A hemispherical type or a shell type It is applicable also to this LED light-emitting device.

DESCRIPTION OF SYMBOLS 1 Blue LED element 3 Bump 4 Substrate 5, 6 Wiring electrode 7 Reflection frame 8 Fluorescent resin (wavelength conversion member)
10, 11 Optical film layer (dielectric multilayer film)
21, 24, 27 Emission spectrum 22, 23, 25, 26, 28, 29 Reflective characteristics of optical film layer 50, 55, 57, 58, 60, 65 LED light emitting device

Claims (6)

In an LED light-emitting device in which an LED element is mounted on a substrate and the upper surface side of the LED element is sealed with a wavelength conversion member that absorbs emitted light and converts the wavelength,
An LED light emitting device comprising an optical film layer for controlling optical characteristics of emitted light on an upper surface of the wavelength conversion member, wherein the optical film layer has a dielectric multilayer film formed in a ring shape.   2. The LED light emitting device according to claim 1, wherein the optical film layer formed in the ring shape includes a plurality of concentric dielectric multilayer films having different optical characteristics.   The LED element is a blue LED element, the wavelength conversion member is a fluorescent resin containing yellow fluorescent particles, and the dielectric multilayer film has an optical characteristic of reflecting yellow light corresponding to color unevenness of emitted light. The LED light-emitting device according to claim 1, wherein the LED light-emitting device is provided.   The LED element is a blue LED element, the wavelength conversion member is a fluorescent resin containing yellow fluorescent particles and red fluorescent particles, and the dielectric multilayer film has yellow light and red light corresponding to the color unevenness of the emitted light. The LED light-emitting device according to claim 1, wherein the LED light-emitting device has an optical characteristic of reflecting light.   The LED element is a blue LED element, the wavelength conversion member is a fluorescent resin containing green fluorescent particles and red fluorescent particles, and the dielectric multilayer film has green light and red light corresponding to color unevenness of emitted light. The LED light-emitting device according to claim 1, wherein the LED light-emitting device has an optical characteristic of reflecting light.   The LED light-emitting device according to claim 1, wherein a reflective frame is provided on an upper surface of the substrate, and the fluorescent resin is filled in the reflective frame. .

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