JP5709943B2 - LED light source manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing an LED light source, and more particularly to a method for manufacturing an LED light source in which part of light emitted from an LED is wavelength-converted by a phosphor.

  In recent years, various products have been developed for LED light sources as the brightness of the LED light sources increases. In particular, in the white LED light source that can be realized by the development of the blue LED element, the advantages of low power consumption and long life of the LED light source are added, and fluorescent lamps currently used for general lighting and interior lights, etc. It is attracting attention as a new lighting alternative to incandescent bulbs.

  FIG. 18 is a cross-sectional view of the LED light source 10.

  In the LED light source 10, the LED element 101 is disposed on a substrate. The substrate is obtained by patterning a wiring conductor 103 for supplying power to an LED on a base material 102. The LED element 101 is mounted using a die bond paste, an Ag paste, or the like when mounted on the substrate. Further, the LED element 101 emits light by being supplied with electric power from the outside via the wiring conductor 103 and the bonding wire 104 of the substrate.

  A sealing material 106 for protecting the LED element 101 is formed around the LED element 101. In addition, the first phosphor is included in a state of being mixed with the resin of the sealing material 106. The phosphor absorbs part of the light emitted from the LED element 101 and converts the wavelength to emit light. In addition, a reflection frame 105 is disposed outside the sealing material 106.

  In the LED light source 10, a nitride compound semiconductor that emits blue light is used as the LED element 101, and an yttrium aluminum garnet (YAG) phosphor activated with cerium is used as the first phosphor. Thereby, in the white LED light source 10, the blue light from the LED element 101 and the yellow light from the first phosphor are mixed to emit pseudo white light.

  In the LED light source 10 that emits pseudo white light by combining the LED element 101 and the first phosphor, there is a problem that chromaticity varies between individuals unless the ratio of blue light to yellow light is made constant. It was.

  Possible causes of chromaticity variation among the LED light sources 10 include variation in the amount of encapsulant, amount of phosphor in the encapsulant, variation in phosphor dispersion, and variation in phosphor particle size. It is done.

  FIG. 19 is a diagram illustrating an example of chromaticity coordinates.

  For example, the chromaticity of the LED light source 10 shifts from white to yellow on the chromaticity coordinates when the amount of phosphor of the encapsulant 106 is large, and when the amount of phosphor of the encapsulant 106 is small. , The color shifts from white to blue on the chromaticity coordinates. Such variations in chromaticity of LED light sources among individuals are difficult to avoid in manufacturing, and it is very difficult to mass-produce only LED light sources having uniform chromaticity.

  Patent Document 1 describes a method of adjusting the chromaticity by changing the path of the light beam from the LED element by changing the thickness of the upper part of the transparent resin layer after curing by polishing or coating.

  FIG. 20 is a diagram for explaining the chromaticity adjustment method disclosed in Patent Document 1. In FIG.

  In the LED light source 20, the LED element 101 is disposed on a substrate composed of a base material 102 and a wiring conductor 103, and is electrically connected to the wiring conductor 103 via a bonding wire 104. The inside of the reflection frame 105 disposed on the substrate is filled with a sealing material. The sealing material precipitates the first phosphor 21 in the lower part, and is cured in the state of only the transparent resin 22 in the upper part.

  FIG. 20A shows an example in which the upper transparent resin 22 is polished until the target chromaticity is reached in the chromaticity adjustment process. In the example of FIG. 20A, polishing is performed until the position 23 on the resin surface before polishing becomes the position 24 on the resin surface after polishing. For this reason, since light is confined in a narrower space (transparent resin), more reflections are repeated, and the probability that the light from the LED element 101 meets the first phosphor increases, and the wavelength conversion rate. Becomes higher. Therefore, the chromaticity of the LED light source 20 is adjusted from blue to yellow.

  FIG. 20B shows an example in which the resin surface is further increased to the position 25 by further increasing the resin above the position 23 on the resin surface in the chromaticity adjustment process. In the example of FIG. 20B, since the amount of the resin has increased, light passes through a wider space (transparent resin), and the probability that the light from the LED element 101 meets the first phosphor is increased. The wavelength conversion rate is lowered. Therefore, the chromaticity of the LED light source 30 is adjusted from yellow to blue.

  As described above, it is possible to adjust the chromaticity by simply increasing or decreasing the amount of the transparent resin. However, when the outer shape of the LED light source is limited, it is difficult to increase or decrease the amount of transparent resin. Further, when the polishing is performed, the LED light source is damaged such as force and scratches. For example, the wire bonding is broken and the reflection frame is damaged.

JP 2004-186488 A (page 4, pages 8, FIG. 2)

  Then, an object of this invention is to provide the manufacturing method of the LED light source which made it possible to eliminate the trouble mentioned above.

  Another object of the present invention is to provide a method for manufacturing an LED light source that can be easily adjusted for chromaticity with little change in the outer shape, little damage in the process of chromaticity adjustment.

  The LED light source manufacturing method according to the present invention includes an LED light source that includes an LED element, a phosphor that absorbs blue light emitted from the LED element, converts the wavelength, and emits yellow light, and a periphery of the LED element. In accordance with a step of emitting pseudo white light and measuring the chromaticity of the LED light source, and a chromaticity correction amount for adjusting the measured chromaticity to a desired chromaticity Considering the change in chromaticity when a light scattering part consisting of a concavo-convex pattern that scatters part of the light emitted from the LED element is formed inside and outside the critical angle region of the surface of the sealing material. A step of determining the position of the light scattering portion, and a step of forming the light scattering portion at the determined position in order to adjust the pseudo white light emitted from the LED light source from yellow or blue. Features.

  Furthermore, in the manufacturing method of the LED light source according to the present invention, in the forming step, in order to adjust the pseudo white light emitted from the LED light source to yellow, the light scattering portion is provided in the region within the critical angle of the surface of the sealing material. It is preferable to form the light scattering portion outside the region within the critical angle of the surface of the sealing material in order to adjust the pseudo white light emitted from the LED light source to be blue.

  Furthermore, in the method for manufacturing an LED light source according to the present invention, it is preferable that the light scattering portion is formed in a shifted position in accordance with the chromaticity correction amount in the forming step.

  Furthermore, in the manufacturing method of the LED light source which concerns on this invention, it is preferable at a formation process that a light-scattering part is formed by shifting the position of the same area with the same pattern shape.

  Furthermore, in the manufacturing method of the LED light source which concerns on this invention, it is preferable that a light-scattering part is formed so that it may have the same scattering efficiency at a formation process.

  Furthermore, in the manufacturing method of the LED light source which concerns on this invention, it is preferable that a light-scattering part contains the unevenness | corrugation formed in dot shape.

  Furthermore, in the manufacturing method of the LED light source which concerns on this invention, it is preferable that a light-scattering part contains the unevenness | corrugation formed in linear form.

  Furthermore, in the manufacturing method of the LED light source which concerns on this invention, it is preferable that a light-scattering part contains the unevenness | corrugation formed in planar shape.

  According to the present invention, there is provided an LED light source capable of easily adjusting chromaticity by forming a light scattering portion on the surface of the sealing material, hardly changing the outer shape, causing little damage in the process of adjusting chromaticity. be able to.

It is sectional drawing which shows the LED light source which concerns on this invention. It is a detailed view of the shape of the light scattering unit 107. It is a figure which shows the example of the light emission spectrum of a LED light source. It is a figure which shows the example of chromaticity coordinates. It is a figure for demonstrating the behavior of the light in a light-scattering part. It is a figure for demonstrating chromaticity correction amount distribution and a critical angle. It is a figure which shows the example of another LED light source. It is a figure which shows the example of another LED light source. It is a figure which shows the example of another LED light source. It is a figure which shows another LED light source. It is a figure which shows the example of another chromaticity coordinate. It is a figure which shows the example of another LED light source. It is a figure for demonstrating the shift of a light-scattering part. It is a figure which shows the example of the LED light source which shifted. It is a figure which shows the relationship between shift distance d and chromaticity correction amount (DELTA) x. It is a figure which shows the example of another chromaticity coordinate. It is a figure which shows the pattern of the light-scattering part for forming it shifting. It is a cross-sectional surface of the white LED light source 10. It is a figure which shows an example of chromaticity coordinates. It is a figure for demonstrating the chromaticity adjustment method shown by patent document 1. FIG.

  The LED light source manufacturing method according to the present invention will be described below with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to these embodiments, but extends to the invention described in the claims and equivalents thereof.

  FIG. 1 is a view showing an LED light source according to the present invention.

  FIG. 1A is a top view of the LED light source 100, and FIG. 1B is a cross-sectional view taken along line AA ′ of FIG.

  The LED element 101 is disposed on a substrate composed of a base material 102 and a wiring conductor 103, and is electrically connected to the wiring conductor 103 via a bonding wire 104. As the base material 102, those having insulating properties and heat resistance are preferable, and as the material, glass epoxy, ceramic, BT resin, silicone or the like is used. The LED element 101 is mounted on the substrate using a die bond paste, an Ag paste, or the like. Electric power is supplied to the LED element 101 and the wiring conductor 103 via the bonding wire 104.

  A sealing material 106 for protecting the LED element 101 is formed around the LED element 101. As the sealing material 106, a transparent epoxy resin or silicone resin is used. Further, the sealing material 106 includes a first phosphor mixed with a resin. The first phosphor absorbs a part of the light emitted from the LED element 101 and emits the wavelength-converted light. Further, a scattering material for uniformly dispersing the light emitted from the sealing material 106 and the LED element 101 may be included.

  A reflection frame 105 is disposed outside the sealing material 106. The reflection frame 105 is for efficiently irradiating the entire surface with light from the LED element 101 and the first phosphor, and a material having a high surface reflectance such as resin, ceramic, or metal material is used. .

  In the LED light source 100, a nitride compound semiconductor that emits blue light is used as the LED element 101, and an yttrium aluminum garnet (YAG) phosphor activated with cerium is used as the first phosphor. Thereby, in the LED light source 100, the blue light from the LED element 101 and the yellow light from the first phosphor are mixed to emit pseudo white light.

  Further, in the LED light source 100, since ten light scattering portions 107 are formed in a circular shape in the region 71 within the critical angle of the surface 108 of the sealing material 106, the chromaticity of the emitted light from the LED light source 100 is determined. Is adjusted to the yellow side on the chromaticity coordinates. The dotted line 72 indicates the boundary line of the region within the critical angle. The adjustment of the critical angle and chromaticity will be described later.

  The light scattering portion refers to a portion where a light scattering shape is formed. The shape and size of the light-scattering shape do not need to be constant. For example, a number of light-scattering shapes with various shapes and size distributions overlap to form a light-scattering part. You may do it. By the way, when a certain light traveling from the inside of the LED light source 100 to the outside is scattered by the light scattering portion 107 provided on the surface 108, 60% of the intensity of the original light travels as it is without being scattered. When 40% of the original light intensity is uniformly scattered without changing the direction (that is, approximately 20% of the original light intensity is scattered toward the outside of the LED light source 100, and the original light intensity is scattered. Is scattered toward the inside of the LED light source 100), the scattering efficiency of the light scattering portion 107 is defined as 40%. Similarly, when certain light traveling from the inside to the outside of the LED light source 100 is scattered by the light scattering portion 107 provided on the surface 108, 40% of the intensity of the original light is not scattered and remains as it is. When the traveling direction is not changed, 60% of the intensity of the original light is uniformly scattered (that is, approximately 30% of the intensity of the original light is scattered toward the outside of the LED light source 100 and When approximately 30% of the intensity is scattered toward the inside of the LED light source 100), the scattering efficiency of the light scattering portion 107 is defined as 60%. Further, the LED element indicates a semiconductor light emitting device, and the LED light source indicates an electronic component on which the LED element or the like is mounted and packaged.

  FIG. 2 is a detailed view of the shape of the light scattering portion.

  FIG. 2A is a diagram illustrating the light scattering unit 107 used in the LED light source 100. The light scattering portion 107 is formed as a dot-like depression, and a plurality of irregularities 109 that scatter light are formed on the surface of the depression. The unevenness 109 has a surface shape that is clearly different from the surface 108 of the original flat sealing material. The dot-like depression can be formed very easily using a needle, for example. The unevenness 109 for scattering light, which is formed on the surface of the dot-like depression, is formed by roughening the surface by inserting a needle into the sealing material.

  FIG. 2B is a diagram illustrating another light scattering unit 110. The light scattering portion 110 is formed by forming irregularities 109 that scatter light by scratching, scraping, or polishing the surface 108 of the sealing material 106. The light scattering unit 110 has the same effect as the light scattering unit 107 shown in FIG.

  FIG. 2C is a diagram showing still another light scattering unit 111. The light scattering portion 111 is formed by forming irregularities 109 for scattering light by cutting the surface 108 of the sealing material 106. The light scattering portion 111 has the same effect as the light scattering portion 107 shown in FIG.

  FIG. 2D is a diagram showing still another light scattering unit 112. The light scattering portion 112 is obtained by attaching unevenness 109 separately formed on the surface 108 of the sealing material 106 with a seal or the like. The light scattering portion 112 has the same effect as the light scattering portion 107 shown in FIG.

  As described above, the light scattering portion can be formed by various methods. In addition, said light-scattering part is an example, Comprising: It is possible to utilize the light-scattering part formed by the other method. For example, the light scattering portion can be formed by attaching or embedding particles to the surface 108, or by attaching a separately created light scattering shape to the surface 108. The shape of the light scattering portion is not limited to the dot shape, and may be various shapes such as a linear shape and a planar shape. Moreover, if it is a linear light-scattering part, it can be formed with things like a cutter and a scriber, and if it is a planar light-scattering part, it can be easily realized by polishing. Can do. Further, in the process of forming the light scattering portion, the irregularities 109 that scatter light are formed on the surface in any case such as a dot shape, a linear shape, or a planar shape.

  For example, by attaching a nanocrystal having a diameter of 200 nm or less on the surface 108, light that causes Rayleigh scattering more strongly with respect to blue light emitted from the LED element 101 than yellow light from the first phosphor. A scattering part can be formed. Rayleigh scattering refers to scattering that occurs when the shape of light scattering is shorter than or equal to the wavelength of light. As will be described later, when the light scattering portion is formed in the region 71 within the critical angle, the main purpose is to scatter blue light, and thus the light scattering portion that causes Rayleigh scattering is particularly useful. . It is also possible to form a light scattering portion that causes Mie scattering that occurs when the shape of light scattering is longer than the wavelength of the light.

  Next, the effect of chromaticity adjustment will be described.

  As an example for showing the effect of chromaticity adjustment, the number of light scattering portions 107 (see FIG. 2A) formed on the surface 108 of the sealing material 106 is stepwise set to 0, 5, and 10 , 15 and 20 were changed. The case where the number of light scattering portions 107 is 10 corresponds to the LED light source 100 shown in FIG. 1, and the case where the number of light scattering portions 107 is 0 corresponds to the LED light source 10 shown in FIG. Will be.

  FIG. 3 is a diagram illustrating an emission spectrum example of the LED light source.

  In FIG. 3, the dotted line 31 indicates the spectrum of the LED light source 10 where the light scattering portion 107 is not formed, and the solid line 30 indicates the spectrum of the LED light source when the number of light scattering portions 107 is 20.

  As is clear from FIG. 3, the spectrum of the LED light source is changed by forming the light scattering portion and adjusting the chromaticity, and the peak near 450 nm derived from the blue LED is reduced, resulting from the yellow phosphor. The peak near 560 nm increases. That is, by forming the light scattering portion, the chromaticity coordinates of the LED light source can be changed in the yellow direction.

  FIG. 4 is a diagram illustrating an example of chromaticity coordinates.

  In FIG. 4, the vertical axis and the horizontal axis indicate chromaticity coordinate changes Δy and Δx, respectively. Note that the chromaticity coordinate change of the LED light source before chromaticity adjustment (when the number of light scattering portions 107 is zero) is the origin (Δy, Δx) = (0, 0).

  In the figure, the chromaticity coordinate change 40 is when the number of light scattering portions 107 is zero, the chromaticity coordinate change 41 is when the number of light scattering portions 107 is five, and the chromaticity coordinate change 42 is when the number of light scattering portions 107 is ten. In this case, the chromaticity coordinate change 43 corresponds to the case where the number of the light scattering portions 107 is 15, and the chromaticity coordinate change 44 corresponds to the case where the number of the light scattering portions 107 is 20.

  As understood from FIG. 4, the chromaticity coordinates of the chromaticity coordinate change 40 are (0, 0), the chromaticity coordinates of the chromaticity coordinate change 41 are (+0.001, +0.002), and the chromaticity coordinate change 42. Are (+0.004, +0.008), the chromaticity coordinates of the chromaticity coordinate change 43 are (+0.006, +0.011), and the chromaticity coordinates of the chromaticity coordinate change 44 are (+0.008, +0.015), which is gradually approaching the yellow direction. Thus, the number of light scattering portions 107 and the amount of change in chromaticity coordinates are substantially proportional, and chromaticity adjustment is possible by forming the number of light scattering portions 107 corresponding to the target amount of change in chromaticity coordinates. Can be understood.

  FIG. 5 is a diagram for explaining the behavior of light in the light scattering portion.

  FIG. 5A is a diagram illustrating an example of an optical path in a place where there is no light scattering portion. When light from the LED element 101 reaches the surface 108 of the encapsulant 106 from the inside of the encapsulant 106 at an angle α that is equal to or less than the critical angle, the incident light 401 from the LED element 101 is almost at the surface 108 of the encapsulant 106. Are not reflected and are emitted to the atmosphere as transmitted light 402. The critical angle is an angle unique to the LED light source 100, which is determined by the wavelength of light emitted from the LED element 101, the refractive index of the sealing material 106, and the like.

  FIG. 5B is a diagram illustrating an example of an optical path in the light scattering portion. When light from the LED element 101 reaches the unevenness 109 formed in the dot-shaped light scattering portion 107 from the inside of the sealing material 106 at an angle α that is equal to or less than the critical angle, 401 of incident light is formed in the light scattering portion 107. The scattered light 109 is scattered and travels as scattered light 403 in various directions. For this reason, when there is a light scattering portion within a critical angle, a part of the scattered light 403 returns to the inside of the sealing material 106, unlike FIG. The scattered light 403 returning to the inside of the sealing material 106 increases the probability that the light emitted from the LED element 101 hits the phosphor existing inside the sealing material 106, and the color conversion efficiency also increases. Therefore, if a light scattering portion is provided within a critical angle, yellow light due to color conversion increases, and the chromaticity of light emitted from the LED light source 100 can be changed in the yellow direction on the chromaticity coordinates. It becomes. In this case, the intensity of light returning to the inside of the LED light source 100 is determined by the scattering efficiency of the light scattering unit 107.

  FIG. 5C is a diagram illustrating an example of an optical path in a place where there is no light scattering portion. When light from the LED element 101 reaches the surface 108 of the encapsulant 106 from the inside of the encapsulant 106 at an angle β that is equal to or greater than the critical angle, incident light from most LED elements 101 on the surface 108 of the encapsulant 106. 401 is reflected, and the reflected light 404 returns to the inside of the sealing material 106.

  FIG. 5D is a diagram illustrating an example of an optical path in the light scattering portion. When light from the LED element 101 reaches the unevenness 109 formed on the dot-shaped light scattering portion 107 from the inside of the sealing material 106 at an angle β equal to or greater than the critical angle, 401 of incident light is formed on the light scattering portion 107. The scattered light 109 is scattered and travels as scattered light 403 in various directions. For this reason, in the case where the light scattering portion is present at a position equal to or greater than the critical angle, a part of the scattered light 403 is emitted to the outside of the sealing material 106 unlike FIG. The scattered light 403 emitted to the outside of the sealing material 106 reduces the light returning to the inside of the sealing material 106, reduces the probability that the light emitted from the LED element 101 hits the phosphor, and reduces the color conversion efficiency. . Therefore, if a light scattering portion is provided at a position above the critical angle, yellow light due to color conversion is reduced, and the chromaticity of light emitted from the LED light source 100 can be changed in the blue direction on the chromaticity coordinates. It becomes. In this case, the intensity of light returning to the inside of the LED light source 100 is determined by the scattering efficiency of the light scattering unit 107.

  As described above, in the LED light source 100 according to the present invention, the light scattering portion 107 is formed on a part of the surface 108 of the sealing material 106 to generate the scattered light 403 and change the light path in the LED light source 100. By doing so, the chromaticity of the LED light source is adjusted. Note that the above chromaticity adjustment method is completely different from the chromaticity adjustment described in Patent Document 1 by simple increase / decrease of the amount of the transparent resin 702 in principle. In the LED light source 100 according to the present invention, the light scattering portion 107 is formed on a part of the surface 108 of the sealing material 106, so that the outer shape of the LED light source 100 is hardly changed and damage caused in the process of chromaticity adjustment. The chromaticity can be easily adjusted.

  FIG. 6 is a diagram for explaining the chromaticity correction amount distribution and the critical angle.

  6A shows an example of the chromaticity correction amount (Δx) distribution, FIG. 6B shows a top view of the LED light source 10, and FIG. 6C shows a cross section taken along line L in FIG. 6B. FIG.

  FIG. 6A shows a chromaticity correction amount (Δx) distribution 70 toward the yellow side by the light scattering portion provided on the line L in FIG. 6B. For example, as shown in FIG. 6B, when only the light scattering portion 86 is formed on the surface 108, the color of the LED light source corresponds to the shaded portion 73 in the chromaticity correction amount distribution 70 of FIG. The degree will be corrected to the yellow side. Similarly, as shown in FIG. 6B, when only the light scattering portion 92 having the same scattering efficiency as that of the light scattering portion 87 is formed on the surface 108, diagonal lines in the chromaticity correction amount distribution 70 of FIG. The chromaticity of the LED light source is corrected to the yellow side by an amount corresponding to the portion 74. Thus, even if a light scattering portion having the same scattering efficiency and the same area is formed on the surface 108, the chromaticity correction amount (Δx) by the light scattering portion is large at the center portion of the surface 108 and small at the peripheral portion. . This is because the LED element is arranged directly below the center O of the surface 108, so that the intensity of blue light is strong, and the influence of scattering by the light scattering portion 87 is strong, and at the center O of the surface 108, Since the light path from the light emitted from the LED element to the surface 108 is the shortest, the probability of encountering the phosphor is low, and the probability of reaching the surface 108 with blue light is high, so the influence of the light scattering portion 87 is strong. Because. As described above, by using the chromaticity correction amount distribution 70, it is possible to determine in advance how much the chromaticity of the LED light source can be changed by forming what light scattering portion at which position. Is possible.

  In the chromaticity correction amount distribution 70 of FIG. 6A, a chromaticity meter is fixedly disposed right above the center O of the LED light source 10, and only the light scattering portion 80 is formed on the surface 108 first. The degree is measured, and a chromaticity correction amount that is a difference from the chromaticity when no light scattering portion is formed is calculated. Next, a light scattering unit 81 is further formed to measure the chromaticity, and a chromaticity correction amount that is a difference from the chromaticity when only the light scattering unit 80 is formed is calculated. As described above, the chromaticity correction amount distribution 70 for a predetermined LED light source can be obtained by calculating the chromaticity correction amount each time the light scattering portions 80 to 94 are formed on the line L.

  The chromaticity correction amount distribution 70 in FIG. 6A is for the line L in FIG. 6B, but a two-dimensional chromaticity correction amount distribution for the surface 108 can also be obtained. is there. In this case, as shown in FIG. 6B, the chromaticity correction amount may be calculated every time a plurality of light scattering portions are provided not only on a predetermined line but also on the entire surface 108.

  The angle γ shown in FIG. 6C is the critical angle, and the region 71 in FIG. 6B shows the region within the critical angle. As described with reference to FIG. 5, the chromaticity of the light emitted from the LED light source 100 is adjusted to the yellow side on the chromaticity coordinates by providing the light scattering portion in the region 71 within the critical angle. It becomes possible to do. Moreover, although it is the surface 108 of the sealing material 106, by providing a light scattering part outside the region 71 within the critical angle, the chromaticity of the light emitted from the LED light source 100 is more blue on the chromaticity coordinates. It becomes possible to adjust to the side.

  FIG. 7 is a diagram illustrating an example of another LED light source.

  FIG. 7B is a top view of another LED light source 120, and FIG. 7A is a diagram illustrating a chromaticity correction amount distribution according to FIG. 7B. Similarly, FIG. 7D is a top view of still another LED light source 130, and FIG. 7C is a diagram showing a chromaticity correction amount distribution according to FIG. 7D.

  The LED light sources 120 and 130 differ only in the light scattering portion provided on the surface 108 of the sealing material 106, and other portions are the same as the LED light source 100 shown in FIG. Is omitted. In FIGS. 7B and 7D, a dotted line 72 indicates the boundary line of the region within the critical angle (see FIG. 6).

  In the LED light source 120 shown in FIG. 7B, a circular light scattering portion 121 is formed in a region within a critical angle on the surface 108. The light scattering portion 121 is formed by polishing the surface 108 as in the light scattering portion 110 shown in FIG. However, other light scattering portions as shown in FIGS. 2A, 2C and 2D may be formed.

  As shown in FIG. 7B, by providing the light scattering portion 121 in a region within the critical angle on the surface 108, the chromaticity of the emitted light of the LED light source 120 is adjusted from yellow on the chromaticity coordinates. can do. Further, the chromaticity correction amount by the light scattering unit 121 shown in FIG. 7B corresponds to the area of the shaded portion 75 in the chromaticity correction amount distribution 70 of FIG.

  In the LED light source 130 shown in FIG. 7D, four dot-shaped light scattering portions 131 to 134 are formed in a region within a critical angle on the surface 108. The four light scattering portions 131 to 134 are assumed to have the same scattering efficiency as that of the light scattering portion 121 in FIG.

  By providing the four light scattering portions 131 to 134 in the region within the critical angle on the surface 108 as shown in FIG. It can be adjusted more than yellow. Further, the chromaticity correction amounts by the light scattering portions 131 to 134 shown in FIG. 7D correspond to the area of the shaded portion 76 in the chromaticity correction amount distribution 70 of FIG. By comparing with the shaded portion 75 in the chromaticity correction amount distribution 70 shown in FIG. 7A, the degree of chromaticity correction amount of the light scattering portions 131 to 134 can be known.

  FIG. 8 is a diagram showing another example of the LED light source.

  FIGS. 8A and 8B are the same as FIGS. 7A and 7B. FIG. 8D is a top view of still another LED light source 140, and FIG. 8C is a diagram showing a chromaticity correction amount distribution according to FIG. 8D.

  The LED light source 140 is different only in the light scattering portion provided on the surface 108 of the sealing material 106, and other portions are the same as the LED light source 100 shown in FIG. To do. In FIG. 8D, the dotted line 72 indicates the boundary line of the region within the critical angle (see FIG. 6), and the dotted line 121 indicates the outline of the light scattering portion 121 shown in FIG. .

  In the LED light source 140, a circular light scattering portion 141 smaller than the light scattering portion 121 shown in FIG. 8B is formed in a region within a critical angle on the surface 108. The light scattering portion 141 is formed by polishing the surface 108 as in the light scattering portion 131 shown in FIG. 8D, and the scattering efficiency is the same as that of the light scattering portion 121.

  As shown in FIG. 8D, the light scattering portion 141 is provided in a region within the critical angle on the surface 108, thereby adjusting the chromaticity of the light emitted from the LED light source 140 to be yellower than the chromaticity coordinates. can do. Further, the chromaticity correction amount by the light scattering portion 141 shown in FIG. 8D corresponds to the area of the shaded portion 77 in the chromaticity correction amount distribution 70 of FIG. By comparing with the shaded portion 75 in the chromaticity correction amount distribution 70 shown in FIG. 8A, the degree of chromaticity correction amount of the light scattering portion 141 can be known. As described above, if the light scattering portion has the same scattering efficiency, it is possible to change the chromaticity correction amount (that is, change the chromaticity adjustment amount) by changing the area.

  FIG. 9 is a diagram illustrating another example of the LED light source.

  FIGS. 9A and 9B are the same as FIGS. 7A and 7B. FIG. 9D is a top view of still another LED light source 150, and FIG. 9C is a diagram showing a chromaticity correction amount distribution according to FIG. 9D.

  The LED light source 150 is different only in the light scattering portion provided on the surface 108 of the sealing material 106, and the other portions are the same as the LED light source 100 shown in FIG. To do. In FIG. 9D, a dotted line 72 indicates the boundary line of the region within the critical angle (see FIG. 6).

  In the LED light source 150 shown in FIG. 9D, a circular light scattering portion 151 is formed in a region within a critical angle on the surface 108. The light scattering portion 151 is formed by polishing the surface 108 similarly to the light scattering portion 110 shown in FIG. 2B, and has the same area as the light scattering portion 121 shown in FIG. 9B. However, the scattering efficiency of the light scattering portion 151 is set to be lower than the scattering efficiency of the light scattering portion 121.

  As shown in FIG. 9D, by providing the light scattering portion 151 in a region within the critical angle on the surface 108, the chromaticity of the emitted light of the LED light source 150 is adjusted to be more yellow than the chromaticity coordinates. can do. Further, the chromaticity correction amount by the light scattering unit 151 shown in FIG. 9D corresponds to the area of the hatched portion 78 in the chromaticity correction amount distribution 70 ′ of FIG. 9C. Although the area of the light scattering portion 151 is the same as that of the light scattering portion 121, the scattering efficiency of the light scattering portion 151 is set to be lower than the scattering efficiency of the light scattering portion 121. It can be understood that the degree correction amount is lower than the chromaticity correction amount of the light scattering unit 121.

  FIG. 10 is a diagram showing still another LED light source.

  FIG. 10A shows an example of the chromaticity correction amount distribution of the LED light source 160, FIG. 10B shows a top view of the LED light source 160, and FIG. 10C shows the AA ′ cross section of FIG. FIG.

  The difference between the LED light source 160 shown in FIG. 10 and the LED light source 100 shown in FIG. 1 is only the light scattering portions 161 and 162 provided on the surface 108 of the LED 160, and the description of other portions is omitted. In addition, the dotted line 72 in FIG.10 (b) has shown the boundary line of the area | region within a critical angle (refer FIG. 7).

  The light scattering portions 161 and 162 are formed by polishing the surface 108 as in the light scattering portion 110 shown in FIG. 2B, and the scattering efficiency is the same. However, other light scattering portions as shown in FIGS. 2A, 2C and 2D may be formed. Further, the light scattering portions 161 and 162 are disposed outside the region within the critical angle. As shown in FIG. 10, by providing the two light scattering portions 161 and 162 outside the region within the critical angle on the surface 108, the chromaticity of the emitted light of the LED light source 160 is made to be blue on the chromaticity coordinates. Can be adjusted. Further, the chromaticity correction amount toward the yellow side by the light scattering unit 161 illustrated in FIG. 10B corresponds to the area of the shaded portion 79 in the chromaticity correction amount distribution 70 illustrated in FIG. Since the hatched portion 79 in FIG. 10A is on the minus side, it means that the light scattering portion 161 can adjust the chromaticity of the emitted light of the LED light source 160 from blue on the chromaticity coordinates. doing.

  FIG. 11 is a diagram illustrating another example of chromaticity coordinates.

  In FIG. 11, the vertical axis and the horizontal axis indicate chromaticity coordinate changes Δy and Δx, respectively. Note that the chromaticity coordinate change of the LED light source (when no light scattering portion is formed) before chromaticity adjustment is set to the origin (Δy, Δx) = (0, 0).

  In the figure, a chromaticity coordinate change 80 indicates a case where there is no light scattering portion (corresponding to the LED light source 10 in FIG. 18), and a chromaticity coordinate change 81 indicates a light scattering portion 161 outside the region within the critical angle on the surface 108. And 162 are provided (corresponding to the LED light source 160 in FIG. 10).

  Further, as understood from FIG. 11, the chromaticity coordinates of the chromaticity coordinate change 80 are (0, 0), and the chromaticity coordinates of the chromaticity coordinate change 81 are (0.0018, −0.0024), Approaching blue direction. Thus, it can be understood that the chromaticity adjustment from blue can be achieved by providing the light scattering portion outside the region within the critical angle on the surface 108.

  FIG. 12 is a diagram illustrating another example of the LED light source.

  FIG. 12A is a top view of the LED light source 170. Since the difference between the LED light source 170 shown in FIG. 12A and the LED light source 100 shown in FIG. 1 is only the light scattering portion 171 provided on the surface 108 of the LED 170, other description is omitted. In addition, the dotted line 72 in Fig.12 (a) has shown the boundary line of the area | region within a critical angle (refer FIG. 7). In the LED light source 170, a plurality of dot-like light scattering portions 171 are arranged along the outer edge of the upper surface 108 of the LED light source 170 outside the region within the critical angle. The plurality of light scattering portions 171 are indentations formed using a needle, like the light scattering portion 107 shown in FIG. However, you may form other light-scattering parts as shown to FIG.2 (b)-(d). By providing a plurality of light scattering portions 171 outside the region within the critical angle on the surface 108 as shown in FIG. 12 (a), the chromaticity of the emitted light from the LED light source 170 is made more blue than on the chromaticity coordinates. Can be adjusted.

  FIG. 12B is a top view of the LED light source 180. Since the difference between the LED light source 180 shown in FIG. 12B and the LED light source 100 shown in FIG. 1 is only the light scattering portion 181 provided on the surface 108 of the LED 180, other description is omitted. In addition, the dotted line 72 in FIG.12 (b) has shown the boundary line of the area | region within a critical angle (refer FIG. 7). In the LED light source 180, a plurality of dot-like light scattering portions 181 are arranged in a circle outside the region within the critical angle. The plurality of light scattering portions 181 are indentations formed using a needle, like the light scattering portion 107 shown in FIG. However, you may form other light-scattering parts as shown to FIG.2 (b)-(d). By providing a plurality of light scattering portions 181 outside the region within the critical angle on the surface 108 as shown in FIG. 12 (b), the chromaticity of the emitted light of the LED light source 180 is made more blue than on the chromaticity coordinates. Can be adjusted.

  FIG. 12C is a top view of the LED light source 190. Since the difference between the LED light source 190 shown in FIG. 12C and the LED light source 100 shown in FIG. 1 is only the light scattering portions 191 to 194 provided on the surface 108 of the LED 190, other explanations are omitted. . In addition, the dotted line 72 in FIG.12 (c) has shown the boundary line of the area | region within a critical angle (refer FIG. 7). In the LED light source 190, a plurality of strip-shaped light scattering portions 191 to 194 are concentrically arranged outside the region within the critical angle. The plurality of light scattering portions 191 to 194 are formed by cutting the surface in the same manner as the light scattering portion 110 shown in FIG. However, other light scattering portions as shown in FIGS. 2A, 2C and 2D may be formed. By providing a plurality of light scattering portions 191 to 194 outside the region within the critical angle on the surface 108 as shown in FIG. 12C, the chromaticity of the emitted light of the LED light source 190 is expressed on the chromaticity coordinates. It can be adjusted more than blue.

  FIG. 12D is a top view of the LED light source 200. Since the difference between the LED light source 200 shown in FIG. 12D and the LED light source 100 shown in FIG. 1 is only the light scattering portion 201 provided on the surface 108 of the LED 200, other description is omitted. In addition, the dotted line 72 in FIG.12 (d) has shown the boundary line of the area | region within a critical angle (refer FIG. 7). In the LED light source 200, a strip-shaped light scattering portion 201 is disposed outside the region within the critical angle. The light scattering portion 201 is formed by polishing the surface in the same manner as the light scattering portion 110 shown in FIG. However, other light scattering portions as shown in FIGS. 2A, 2C and 2D may be formed. By providing the light scattering part 201 outside the region within the critical angle on the surface 108 as shown in FIG. 12D, the chromaticity of the emitted light of the LED light source 200 is adjusted to be blue from the chromaticity coordinates. can do.

  FIG. 13 is a diagram for explaining shifting of the light scattering portion.

  FIGS. 13A and 13B show the same state as FIGS. 7A and 7B. That is, by providing the light scattering portion 121 in a region within the critical angle on the surface 108, the chromaticity of the emitted light from the LED light source 120 is adjusted to be yellower than the chromaticity coordinates.

  FIG. 13D shows an LED light source 120 ′ in which the light scattering unit 121 of FIG. 13B is shifted to the right side in the drawing by a distance d as a light scattering unit 122. A shaded portion 75 in the chromaticity correction amount distribution 70 in FIG. 13A indicates the chromaticity correction amount of the LED light source 120, and a shaded portion 125 in the chromaticity correction amount distribution 70 in FIG. The chromaticity correction amount of 'is shown. 13A and 13C, the area of the shaded portion 75> the area of the shaded portion 125. As described above, the chromaticity correction amount can be changed (adjusted) by shifting the light scattering portion having the same scattering efficiency, the same shape, and the same area on the surface 108.

  The light scattering unit 121 and the light scattering unit 122 are both provided in the region within the critical angle. However, when the light scattering unit 123 is further shifted to be a critical part, a part of the light scattering unit 123 is critical. It is arranged outside the area within the angle, and the degree of chromaticity adjustment is further different.

  FIG. 14 is a diagram illustrating an example of a shifted LED light source.

  14A is the same drawing as FIG. 13B, and FIG. 14B is a cross-sectional view taken along the line AA ′ of FIG. FIG. 14C is the same as FIG. 13D, and FIG. 14D is a cross-sectional view taken along the line AA ′ of FIG.

  The difference between the LED light source 120 ′ shown in FIGS. 14C and 14D and the LED light source 100 shown in FIG. 1 is only the light scattering part 122 on the LED light source 120 ′, and other explanations are omitted.

  FIG. 15 is a diagram illustrating the relationship between the shift amount (d) and the chromaticity correction amount Δx.

  The chromaticity correction amount Δx was measured by changing the shift amount (d) of the light scattering portion having the same scattering efficiency as the light scattering portion 121 shown in FIG. Point 90 indicating the case where the shift amount d = 0, point 91 indicating the case where the shift amount d = 170 μm, point 92 indicating the case where the shift amount d = 200 μm, point indicating the case where the shift amount d = 220 μm As shown in FIG. 15, a predetermined correlation is seen at a point 94 indicating 93 and a shift amount d = 310.

  FIG. 16 is a diagram showing still another example of chromaticity coordinates.

  In FIG. 16, the vertical axis and the horizontal axis indicate chromaticity coordinate changes Δy and Δx, respectively. Note that the chromaticity coordinate change of the LED light source (when there is no light scattering portion) before chromaticity adjustment is set to the origin (Δy, Δx) = (0, 0). Also, the points 90 to 94 in FIG. 16 correspond to the points 90 to 94 in FIG.

  15 and 16, it is possible to correct the degree of chromaticity adjustment by changing the shift amount d of the light scattering portion of the same size formed by the same method. That is, by forming the light scattering portion 121 as shown in FIGS. 14A and 14B, the chromaticity of the light emitted from the LED light source 120 can be adjusted to the yellow side on the chromaticity coordinates. Further, by increasing the amount d of shifting the light scattering portion having the same shape as the light scattering portion 121, the chromaticity of the light emitted from the LED light source 120 ′ is adjusted to the blue side on the chromaticity coordinates step by step. be able to.

  FIG. 17 is a diagram showing a pattern of the light scattering portion for forming by shifting.

  FIG. 17A shows a pattern similar to that of the light scattering portion 121 shown in FIG.

  FIG. 17B shows a pattern in which a plurality of circular dot-shaped light scattering portions 220 are formed in substantially the same area as the light scattering portion 121. FIG. 17C shows a light scattering portion 230 having a pattern in which a plurality of band-like light scattering portions are formed concentrically within the same area as the light scattering portion 131. Further, FIG. 17D shows a light scattering portion 240 having a pattern in which a grid-like light scattering portion is formed in a square having a predetermined size. The example shown in FIGS. 17A to 17D is an example, and can be used as a pattern of a light scattering portion for shifting and forming other patterns.

  Hereinafter, a method for adjusting the chromaticity of the LED light source will be described.

  First, as shown in FIG. 18, the LED light source 10 in which the light scattering portion is not formed is manufactured, the LED light source is caused to emit light, and the chromaticity of the emitted light is measured.

  Next, when the measured chromaticity is not the desired chromaticity, a light scattering portion for performing adjustment according to the chromaticity difference between the measured chromaticity and the desired chromaticity is used as the surface 108 of the LED light source. Form on top. If the relationship between the chromaticity difference and the type of the light scattering portion to be formed is determined in advance and the light scattering portion is formed accordingly, the cost and time required for chromaticity adjustment can be saved. For example, if the chromaticity difference is moderate from that of blue, 10 dot-shaped light scattering portions 107 are formed as shown in FIG. 1, and if the chromaticity difference is small, the dot shape shown in FIG. The five light scattering portions 107 are formed in a circular shape, and if the chromaticity difference is large, 20 dot-shaped light scattering portions 107 shown in FIG. 1 are formed in a circular shape.

  Further, as described with reference to FIG. 14, when performing chromaticity adjustment, the light scattering unit always has the same scattering efficiency as the light scattering unit 121 shown in FIG. However, the formation position, that is, the shift amount (d) may be changed according to the chromaticity difference. In that case, the relationship between the chromaticity difference and the shift amount is set in a table or the like, and the light scattering portion may be formed according to the shift amount (d) set in the table based on the measurement result. .

  As described above, using the method of adjusting the chromaticity by shifting the position of the light scattering portion formed by the same method is very effective in manufacturing the LED light source and reducing the cost. In other words, according to the chromaticity difference between the measured chromaticity and the desired chromaticity, it has the same scattering efficiency and the same shape as compared with the case where a plurality of types of light scattering portions are prepared and formed on the surface of the LED light source. If the light scattering portions having the same area are formed by shifting the positions, the light scattering portions can be formed very simply, and the manufacturing cost can be reduced.

  In the above example, the LED element that emits blue light and the LED light source that emits pseudo white light using the phosphor that absorbs blue light and emits yellow light has been described. The present invention is not limited to such a combination, and can be applied to other types of LED light sources. For example, the present invention relates to an LED light source that emits pseudo blue-green light using an LED element that emits blue light and a phosphor that absorbs blue light and emits G-color light, and an LED element that emits blue light and blue light. The present invention can be applied to LED light sources that emit pseudo-violet light using a phosphor that absorbs light and emits R-color light, and their chromaticity correction.

  Furthermore, the present invention relates to an LED element that emits blue light, and as an example, a phosphor that emits G color (hereinafter referred to as “G color phosphor”) and a phosphor that emits R color light (hereinafter referred to as “R color fluorescence”). It can also be applied to an LED light source including a sealing resin in which a plurality of phosphors such as “body” are mixed. For example, the light scattering portion provided on the surface of the RGB-LED light source on the straight line on the chromaticity coordinates determined by the mixture ratio of the G-color phosphor and the R-color phosphor with the chromaticity of the RGB-LED light source It is possible to adjust by.

  Furthermore, the present invention can be applied not only to LED elements that emit blue light but also to LED light sources that include LED elements that emit G-color light.

100, 120, 130, 130 ′, 140, 150, 160, 170, 180, 190, 200 LED light source 101 LED element 102 substrate 103 wiring conductor 104 bonding wire 105 reflection frame 106 sealing material 107, 110-112, 121 -123, 131-134, 141, 151, 161, 162, 171, 181, 191-194, 201 Light scattering portion 108 Surface of sealing material 109 Concavity and convexity 401 Incident light 402 Transmitted light 403 Scattered light

Claims (8)

An LED element, a phosphor that absorbs blue light emitted from the LED element and converts the wavelength to emit yellow light, and a sealing material that includes the phosphor and is disposed around the LED element, A method of manufacturing an LED light source that emits white light,
Measuring the chromaticity of the LED light source;
In accordance with the chromaticity correction amount for adjusting the measured chromaticity to a desired chromaticity, light emission from the LED element is performed within the region within the critical angle and outside the region within the critical angle of the surface of the sealing material. Taking into account the chromaticity change when forming a light scattering portion consisting of an uneven pattern that scatters a part, determining the position of the light scattering portion;
Forming the light scattering portion at the determined position in order to adjust the pseudo white light emitted from the LED light source from yellow or blue , and
In the forming step, the light scattering portion is formed in a region within a critical angle of the surface of the sealing material in order to adjust the pseudo white light emitted from the LED light source to yellow, and emitted from the LED light source. Forming the light scattering portion outside the region within the critical angle of the surface of the sealing material in order to adjust the pseudo-white light to be blue.
A method of manufacturing an LED light source.   The method of manufacturing an LED light source according to claim 1, wherein in the forming step, the light scattering portion is formed with a position shifted according to the chromaticity correction amount.   2. The method of manufacturing an LED light source according to claim 1, wherein in the forming step, the light scattering portion is formed by shifting the position of the same area with the same pattern shape. In the forming step, the light scattering portion is formed to have the same scattering efficiency, a manufacturing method of the LED light source according to any one of claims 1 to 3. The said light-scattering part is a manufacturing method of the LED light source as described in any one of Claims 1-4 containing the unevenness | corrugation formed in dot shape. The said light-scattering part is a manufacturing method of the LED light source as described in any one of Claims 1-4 containing the unevenness | corrugation formed in linear form. The said light-scattering part is a manufacturing method of the LED light source as described in any one of Claims 1-4 containing the unevenness | corrugation formed in planar shape. The region within the critical angle is a region where the light scattering unit can change the chromaticity of light emitted from the LED light source in the yellow direction on the chromaticity coordinates. The manufacturing method of the LED light source as described in any one.

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