JP2013243306A - Led light source and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To place protruding parts including a second color conversion material on a surface of an LED light source, thereby adjusting the luminous color of light emitted from the surface of the LED light source regardless of the shape of the LED light source.SOLUTION: An LED light source 110-1 includes: an LED chip 1 mounted on a mounting surface 2-1 of a wiring board 2; a sealing part 4 formed by a curable transparent resin 4a containing a first color conversion material 4b and sealing the LED chip 1; and multiple protruding parts 5 formed by a curable transparent resin 5a containing a second color conversion material 5b and formed on a surface 4-1 of the sealing part. Since the protruding parts 5 containing the second color conversion material 5b are placed on the surface 4-1 of the sealing resin, the LED light source 110-1 is able to adjust the luminous color of light emitted from the LED light source regardless of the shape of the LED light source.

Description

  The present invention relates to a structure of an LED light source and a method for manufacturing the LED light source.

  A technique is used in which an LED light source is sealed with a transparent resin mixed with a color conversion material such as a phosphor to obtain an emission color such as white light. However, due to the distribution of the color conversion material in the sealing resin and the shape of the sealing resin, there is a problem that the color tone varies depending on the light emission direction.

Japanese Patent Laid-Open No. 11-46019 JP 2007-35885 A

  Patent Document 1 corrects the color tone of such an LED light source by adding a color conversion material later by inkjet. However, it is difficult to ensure the accuracy of application to a dome-shaped curved surface with a structure that ejects ink. Patent Document 2 forms the second wavelength conversion unit, but requires a molding die and has many restrictions on the shape after molding.

  An object of the present invention is to arrange a protrusion including a second color conversion material on the surface of an LED light source so that the emission color of light emitted from the surface of the light source can be adjusted regardless of the shape of the light source. .

The LED light source of this invention is
An LED chip mounted on the mounting surface of the mounting member;
A curable resin material containing a first color conversion material, and a sealing portion for sealing the LED chip;
It is made of a curable resin material containing a second color conversion material, and has a plurality of protrusions formed on the surface of the sealing portion.

According to the present invention, it is possible to eliminate individual differences between LED light sources while adjusting the light emitted from the LED chip in all directions in an LED light source that adjusts the emission color using a color conversion material.
Further, according to the present invention, even in an LED light source that has a different emission color depending on the direction of light emission due to the shape of the sealing resin, the protrusion containing the second color conversion material is transferred to the surface of the sealing resin. By adjusting, an LED light source that emits light of a uniform color in all directions can be produced.

Sectional drawing of the LED light source 110-1 of Embodiment 1. FIG. The side view at the time of manufacture of LED light source 110-1 of Embodiment 1. FIG. Sectional drawing at the time of taking out the sealing resin material of Embodiment 1. FIG. 4 is a graph of an emission spectrum when there is no protrusion 5 according to the first embodiment. The graph of the emission spectrum in case the protrusion part 5 of Embodiment 1 exists. Sectional drawing of the bullet-shaped LED light source 110-2 of Embodiment 1. FIG. Sectional drawing of the LED light source 120 of Embodiment 2. FIG. Sectional drawing of the LED light source 130 of Embodiment 3. FIG. FIG. 6 is a side view of an LED light source 140 according to a fourth embodiment. FIG. 6 is a top view of an LED light source 140 according to Embodiment 4. Sectional drawing at the time of manufacture of LED light source 140 of Embodiment 4. FIG. The perspective view from the downward direction of the transcription | transfer component of Embodiment 4. FIG. Sectional drawing at the time of application | coating of the transfer component of Embodiment 4, and the LED light source 140. FIG.

Embodiment 1 FIG.
As shown in FIGS. 1, 2, 6, 7, 8, 9, 10 and the like to be described later, the outer shape of the sealing resin (after curing and before the formation of the protrusion) of the LED light source described in the following embodiment is as follows. From the mounting surface on which the LED chip is mounted, it has a raised convex shape in the normal direction of the mounting surface (the direction opposite to the X direction in FIG. 9). The tip of the convex shape is a smooth curved surface (for example, a part of a substantially spherical surface), and the entire shape of the sealing resin is a rotating body shape. Further, the “cross section” of the LED light source means a cross section of a portion corresponding to “YY” in FIG. In the following first to fourth embodiments, the uppermost portion of the convex shape is referred to as a top portion T (shown in FIGS. 9 and 10).

  First, the LED light source 110-1 of Embodiment 1 will be described with reference to FIGS. FIG. 1 is a cross-sectional view of the LED light source 110-1. FIG. 2 is a side view of the LED light source 110-1 at the time of manufacturing. FIG. 3 is a cross-sectional view when the sealing resin 4 in which the first color conversion material 4b is contained in the transparent curable transparent resin 4a is taken out. The sealing resin 4 has a configuration in which the transparent resin 4a contains the first color conversion material 4b.

(Configuration of LED light source 110-1)
As shown in FIG. 1, the LED light source 110-1 includes at least one LED chip 1 mounted on the mounting surface 2-1 of the wiring board 2 (mounting member), the wiring board 2, and the wiring material 3. The sealing resin 4 (sealing portion) and the protrusion 5 are configured. The sealing resin 4 is a mixture of a transparent resin 4a (transparent curable resin material) and a first color conversion material 4b. The wiring board 2 is obtained by bonding an insulating layer 2a and a conductor layer 2b.

(Protrusion 5)
(1) As shown in FIGS. 1 and 2, the protrusion 5 is transferred in a dot shape. That is, as shown in FIGS. 1 and 2, each of the plurality of protrusions 5 formed on the surface 4-1 of the sealing resin has a substantially grain shape.
(2) The protrusion 5 includes a transparent resin 5a that is cured by a reaction such as heat, ultraviolet rays, component volatilization, and moisture, and a second color conversion material 5b.
(3) The transparent resin 5a is a material that can be cured from a liquid such as a silicone resin, an epoxy resin, an olefin resin, an acrylic resin, or a fluororesin. It is also conceivable to use a resin material obtained by synthesizing these materials.
(4) The second color conversion material 5b may be the same color conversion material as the first color conversion material 4b or may be a different color conversion material. The second color conversion material 5b is selected according to the emission color to be adjusted.

  As shown in FIG. 2, the protrusion 5 is transferred by the transfer pin 6. As the material of the projection 5 (sealing resin 4 before curing), a plurality of types in which the transparent resin 5a and the second color conversion material 5b are mixed at different blending ratios are prepared. Transfer pins are prepared corresponding to the plurality of types. In FIG. 2, nine transfer pins 6 are shown, but for each of the nine transfer pins 6, the concentration of the second color conversion material 5 b of the sealing resin 4 transferred as the protrusions 5 is all different. Alternatively, the nine transfer pins 6 may be roughly divided into two groups that transfer the sealing resin 4 having one of two types of concentrations. Or the structure from which the content density | concentration of two color conversion materials differs may be sufficient as at least 2 of several protrusion part. The case where the nine transfer pins 6 all use the same concentration of the sealing resin 4 will be described in the second and third embodiments.

(Transfer pin 6)
The diameter of the tip 6-1 of the transfer pin 6 is, for example, 0.3 mm to 1 mm, and the projection 5 to be transferred has a grain shape with the same diameter. As shown in FIG. 3, the transfer pin 6 has the tip 6-1 immersed in a raw material liquid in which a transparent resin 5a and a second color conversion material 5b are mixed and placed in a container 7, and the raw material liquid is put into the tip part. 6-1.

  The LED chip 1 is fixed to the wiring board 2 with solder or a resin adhesive. The wiring board 2 is a printed board or a flexible printed board, and the LED chip and the wiring board are electrically connected by a wiring material 3.

(Sealing resin 4)
The sealing resin 4 protects the LED chip 1 and the wiring material 3. The first color conversion material 4b converts the wavelength of light from the LED chip 1 and adjusts the emission color. In the first embodiment, the distance L1 (FIG. 1) to the surface of the light source is relatively short above the sealing resin 4 (in the T direction in FIG. 1). On the other hand, the sealing resin 4 is thick in the side surface direction (S direction in FIG. 1), and the distances L2 and L3 from the LED chip 1 to the light source surface are long.
That is, as shown in FIG. 1, L1 <L2 <L3,
It has become. Therefore, since the light emitted in the vertical direction (L1 direction) from the LED chip 1 has a short distance to reach the surface 4-1 of the sealing resin, the amount that is wavelength-converted by the first color conversion material 4b. There are relatively few. On the other hand, the amount of light that is directed in the side surface direction (L3 direction) is relatively wavelength-converted. For this reason, as a result, a difference occurs in the emission color near the surface 4-1 of the sealing resin. In order to reduce the difference in the emission color, after the sealing resin 4 is cured, the protrusions 5 are applied in the form of dots by the transfer pins 6 corresponding to the difference in the emission color.

(Transfer of protrusion 5)
Regarding “corresponding to the difference in emission color”, the transfer of the protrusion 5 by the transfer pin 6 is performed after the LED chip 1 is sealed with the sealing resin 4 (sealing process) and the sealing resin is cured. , The emission color of the emitted light of the LED light source 110-1 in a semi-finished state (without the protrusion 5) is measured (emission color measurement step), and the protrusion formed on the surface 4-1 of the sealing resin based on the measurement result The position of the part 5 may be determined, and the protruding part 5 may be formed at the position (projecting part forming step). Alternatively, without providing the emission color measurement step, for example, the tendency of the difference in emission color in the vicinity of the surface 4-1 of the sealing resin is acquired as data from the measurement result of the sample, and the sealing is performed based on this data. The position of the protrusion 5 to be formed on the surface 4-1 of the stop resin may be determined, and the protrusion 5 may be formed (projection formation process).

(Concentration of protrusion 5)
The protrusions 5 can be arranged from the top (T in FIG. 1) to the side surface (S in FIG. 1) of the sealing resin 4 and are arranged at equal intervals. At this time, the protrusions 5 arranged on the upper side (more in the top T direction) contain more second color conversion material 5b (higher concentration on the upper side), and the protrusions 5 closer to the side surface (S direction) A smaller amount of the second color conversion material 5b is contained (the lower the side, the lower the concentration). Thereby, it adjusts so that the luminescent color of the light inject | emitted from LED light source 110-1 may become uniform. By this adjustment, the amount of the second color conversion material 5b is adjusted in accordance with the color change due to the emission angle of the generated light, so that the light emitted from the LED light source 110-1 is uniform in all directions. Become a color.

  FIG. 4 and FIG. 5 show emission spectra comparing the presence / absence of the protrusion 5 in the first embodiment. FIG. 4 shows a case where the protrusion 5 is not provided. FIG. 5 shows a case where the protrusion 5 is provided. Moreover, both FIG. 4, FIG. A broken line indicates an upward direction (a direction from the LED chip 1 toward the top T). A solid line indicates a side surface direction (a direction from the LED chip 1 toward the side surface S).

(Without protrusion 5)
In FIG. 4 (without protrusions), the upward spectrum (broken line) measured from the top direction of the LED light source has a high peak near 450 nm emitted without wavelength conversion, and the peak near 570 nm after color conversion is Low. With respect to the spectrum (solid line) measured from the horizontal direction, the peak around 450 nm that is not wavelength-converted is low, and the peak near 570 nm after wavelength conversion is high.

(When there is a protrusion 5)
About the spectrum after arrange | positioning the projection part 5 of FIG. 5, the difference of a spectrum is small in the upward direction (broken line) and the horizontal direction (solid line). That is, by arranging the protrusions 5, as shown in FIG. 5, the difference in spectral shape between the upward direction (broken line) and the horizontal direction (solid line) is reduced. As a result, it is possible to correct the light source colors that have different color tones in the upward direction (L1 direction in FIG. 1) and the lateral direction (L3 direction in FIG. 1) to the same color tone.

  As described above, after the sealing resin 4 is cured, the characteristics (light emission color) of the light source (the LED light source 110-1 in a state where no protrusion is formed) are measured, and wavelength conversion is performed according to the measurement result. The color deviation of each LED light source can be eliminated by adjusting the members. Here, “adjusting the wavelength conversion member” means adjusting the concentration of the second color conversion material 5b according to the measurement result of the emission color (FIG. 3) or nine transfer pins shown in FIG. 6 means to determine the density of the second color conversion material 5b to be transferred. Alternatively, it includes determining the position of the protrusion 5 to be formed.

  In the LED light source 110-1 shown in FIG. 1, FIG. 2, etc., the LED chip 1 is mounted on the wiring board 2, and the shape of the sealing resin 4 is relatively thin. It was. On the other hand, the LED light source may be a bullet-shaped LED light source 110-2 as shown in FIG. In the case of the LED light source 110-2, the LED chip 1 is mounted on the mounting surface 8-1 of the lead frame 8 and sealed with the sealing resin 4 as shown in FIG. 6.

  According to the LED light sources 110-1 and 110-2 of the first embodiment described above and the LED light source manufacturing method of the first embodiment, the LED chip in the LED light source of the method of adjusting the emission color by the color conversion material Individual differences of LED light sources can be eliminated while adjusting the emitted light of 1 in all directions. In addition, according to the LED light sources 110-1 and 110-2 and the LED light source manufacturing method of the first embodiment, even in LED light sources that emit different colors depending on the direction of light emission due to the shape of the sealing resin, By transferring and adjusting the protrusion containing the second color conversion material on the surface of the sealing resin, an LED light source that emits light of a uniform color in all directions can be produced.

Embodiment 2. FIG.
Next, the LED light source 120 of Embodiment 2 is demonstrated with reference to FIG. FIG. 7 is a cross-sectional view of the LED light source 120. The LED light source 120 is an embodiment in which the arrangement of the protrusions 5 is provided with high and low arrangement density. In the LED light source 120, the plurality of protrusions 5 are arranged so that the arrangement density gradually decreases as the distance from the top T (predetermined reference position) of the surface of the sealing resin 4 increases.

  As shown in FIG. 7, the LED light source 120 includes at least one LED chip 1, a wiring substrate 2, a wiring material 3, a sealing resin 4, and a plurality of protrusions, similar to the LED light source 110-1 in FIG. 1. 5 is provided.

  Similar to the first embodiment, the protrusions 5 transferred in the form of dots (granular shapes) are composed of the transparent resin 5a and the second color conversion material 5b, as in the first embodiment.

  As shown in the first embodiment, also in the second embodiment, the light emitted from the LED chip 1 in the vertical direction (the direction of the top T) reaches the surface 4-1 of the sealing resin 4. Since the distance L1 is short, the amount of wavelength conversion by the first color conversion material 4b is relatively small. On the other hand, since the distance L2 until reaching the surface 4-1 of the sealing resin 4 is long (L1 <L2), the amount of light directed toward the side surface direction S is relatively wavelength-converted. Therefore, the spectrum difference as shown in FIG. 4 occurs as in the first embodiment.

  Therefore, in the LED light source 120, the protrusions 5 are arranged so that the arrangement density thereof is denser toward the upper side and is more sparser in the side surface direction so that the emission color of light emitted from the LED light source 120 is uniform. adjust. This adjustment makes the emission spectrum equal in all directions, and the light emitted from the LED light source 120 has a uniform color in all directions.

  Depending on the shape (dense arrangement) of the protrusions, a material (liquid protrusion material) having a single compounding ratio can be obtained without changing the compounding ratio (concentration) of the second color conversion material 5b included in the protrusions 5. While being used, the emission color can be adjusted by the angle as in the first embodiment.

Embodiment 3 FIG.
Next, the LED light source 120 of Embodiment 2 is demonstrated with reference to FIG. FIG. 8 is a cross-sectional view of the LED light source 130 according to the third embodiment. The feature of the LED light source 130 of Embodiment 3 is that the plurality of protrusions 5 are mixed with grain shapes having different sizes. More specifically, as shown in FIG. 8, a larger protrusion is formed closer to the top T of the LED light source 130, and a smaller protrusion is formed closer to the side S.

  The basic configuration of the LED light source 130 as the LED light source is the same as that of the LED light source 110-1 and the LED light source 120. As shown in FIG. 8, the LED light source 130 includes at least one LED chip 1, a wiring board 2 (insulating layer 2a, conductor layer 2b), a wiring material 3, a sealing resin 4, and a plurality of protrusions 5. ing. Similarly to the first and second embodiments, the protrusion 5 transferred in a dot shape is composed of a transparent resin 5a and a second color conversion material 5b.

  The transfer pin 6 for transferring the protrusion 5 to the surface 4-1 of the sealing resin is prepared with a plurality of diameters. The protrusion 5 is arranged on the surface 4-1 of the sealing resin as in the first and second embodiments. However, the protrusion 5 can be changed by changing the size of the tip 6-1 of the transfer pin depending on the arrangement position. Adjust the diameter. With this shape, the transfer pin 6 is selected while using a material with a single compounding ratio (resin with a concentration of a single second color conversion material) without changing the compounding ratio of the material contained in the protrusion 5. By doing so, the emission color can be adjusted by the angle as in the first and second embodiments.

Embodiment 4 FIG.
Next, the LED light source 140 of Embodiment 4 is demonstrated with reference to FIGS. In the LED light source 140, as shown in FIGS. 9 and 10, the plurality of protrusions 5-1, 5-2, and 5-3 all have a circumferential shape. The plurality of projecting portions 5-1, 5-2, and 5-3 are sequentially arranged adjacent to each other, and the LED chip 1 from the normal direction (X direction in FIG. 9) of the mounting surface 2-1 of the wiring board 2. When one of the protrusions is seen, one of the adjacent protrusions is disposed inside the circumference of the other protrusion so as to be nested as a whole. FIG. 9 is a side view of the LED light source 140. FIG. 10 is a top view of the LED light source 140. As in the first embodiment, the LED light source 140 includes at least one LED chip 1, a wiring board 2, a wiring material 3, a sealing resin 4, and a protrusion 5. Similarly to the first embodiment, the protrusions 5 (protrusions 5-1, 5-2, 5-3) are transferred to the surface of the sealing resin 4. The protrusion 5 is formed in a concentric shape with the top T as the center.

(Transfer part 9)
The concentric protrusions 5-1 to 5-3 shown in FIGS. 9 and 10 are transferred by the transfer component 9 shown in FIG. The transfer component 9 in FIG. 11 has a circular tip (FIG. 11 is a cross-sectional view). As shown in the perspective view of FIG. 12, the transfer component 9 has a cylindrical shape, and the end surface 9-1 which is the tip has an unevenness in a contact portion with the sealing resin 4. When the liquid resin enters the concave portion (groove), the raw material liquid can be taken out (attached) and transferred. Since the amount of protrusions transferred varies depending on the area of the front end portion of the transfer component and the depth and width of the recess, it is possible to adjust the emission color according to the angle by preparing and selecting a plurality of transfer components.

  More resin is transferred by deepening the concave portion at the tip as shown in FIG. The dimension of the protrusion can be adjusted within a range where the liquid material does not flow. By this method, it is possible to transfer the protrusion with a simple shape as compared with the method of transferring with a transfer pin.

(Manufacturing method of LED light source)
Below, the outline | summary of the manufacturing method of LED light source 110-1,110-2,120,130,140 grade | etc., Described in Embodiment 1-4 is shown.

(1. LED chip sealing process)
First, in the LED chip sealing step, the LED chip mounted on the mounting surface of the mounting member (wiring board 2, lead frame, etc.) is sealed with a curable transparent resin 4a containing the first color conversion material 4b. Stop.
(2. Projection forming step)
Next, a plurality of protrusions 5 are formed on the surface of the cured sealing resin 4 with the curable transparent resin 5a containing the second color conversion material 5b.

(3. Projection forming step)
Furthermore, the “LED light source manufacturing method” may include the following “emission color measurement step” after the “LED chip sealing step” and before the “projection portion forming step”. The emission color measurement process has the following contents. In the emission color measurement step, the emitted light of the LED chip 1 sealed with a curable transparent resin 4a (sealing resin 4) containing the first color conversion material 4b after the “LED chip sealing step”. In this step, the emission color of the emitted light transmitted through the sealing resin 4 is measured. In the “projection portion forming step”, a plurality of projection portions are formed on the surface 4-1 of the sealing resin based on the measurement result of the emission color in the “light emission color measurement step”.

  In the fourth embodiment, the “projection forming step” uses a transfer component 9 in which a plurality of circumferential concave shapes (grooves) are formed on one end surface of a cylindrical shape, thereby forming a plurality of concave shapes. An uncured transparent resin 5a containing the second color conversion material 5b is adhered. Then, the attached transparent resin 5a is transferred to the surface 4-1 of the cured sealing resin.

  In the first to fourth embodiments described above, after the LED chip is sealed with the curable sealing resin mixed with the first color conversion material and the curing of the sealing resin is completed, the color deviation in the angular direction is dealt with. Thus, the LED light source that transfers the curable sealing resin in which the second color conversion material is mixed on the surface of the sealing resin in a dotted (or circumferential) manner has been described.

  Needless to say, the contents described in Embodiments 1 to 4 can be implemented in combination within a consistent range. For example, the first and second embodiments are combined to change the concentration of the second color conversion material 5b in the protrusion 5 (Embodiment 1) and to change the arrangement density of the protrusions (Embodiment 2). You may do it. Further, in addition to these, the size of the protrusion may be changed (Embodiment 3). Further, the fourth embodiment may be combined with the second embodiment (arrangement density of projections) (the arrangement density of the circumferential ground projections is changed), or the third embodiment (projection size). ((Changing the size of the circumferentially shaped ground protrusion). Also, the first embodiment and the fourth embodiment are combined to form a dot-shaped protrusion on the surface of the sealing resin (the embodiment). Both 1) and the circumferential projection (Embodiment 4) may be formed.

  DESCRIPTION OF SYMBOLS 1 LED chip, 2 wiring board, 2-1 mounting surface, 2a insulating layer, 2b conductor layer, 3 wiring material, 4 sealing resin, 4-1 sealing resin surface, 4-2 reference position, 4a transparent resin, 4b 1st color conversion material, 5 protrusion, 5a transparent resin, 5b 2nd color conversion material, 6 transfer pin, 6-1 tip, 7 container, 8 lead frame, 8-1 mounting surface, 9 transfer component .

Claims (9)

An LED chip mounted on the mounting surface of the mounting member;
A curable resin material containing a first color conversion material, and a sealing portion for sealing the LED chip;
An LED light source comprising a curable resin material containing a second color conversion material and comprising a plurality of protrusions formed on the surface of the sealing portion. At least two of the plurality of protrusions are
The LED light source according to claim 1, wherein the concentration of the second color conversion material is different. The plurality of protrusions are
3. The LED light source according to claim 1, wherein the LED light source is arranged so that the arrangement density gradually decreases as the distance from a predetermined reference position on the surface of the sealing portion increases. The plurality of protrusions are
The LED light source according to claim 1, wherein the LED light source has a substantially grain shape. The plurality of protrusions are
The LED light source according to claim 4, wherein the grain shapes having different sizes are mixed. The plurality of protrusions are
Each of them has a circumferential shape and is sequentially disposed adjacent to each other, and when the LED chip is viewed from the normal direction of the mounting surface of the mounting member, one of the adjacent protrusions is adjacent to the other protrusion. The LED light source according to any one of claims 1 to 3, wherein the LED light source is disposed inside the circumference and is nested as a whole. A sealing step of sealing the LED chip mounted on the mounting surface of the mounting member with a curable resin material containing the first color conversion material;
A method for producing an LED light source, comprising: a curable resin material containing a second color conversion material; and a projection forming step of forming a plurality of projections on the surface of the sealing portion. The manufacturing method of the LED light source is as follows:
After the sealing step, the emitted light of the LED chip sealed with the curable resin material containing the first color conversion material, and the emitted color of the emitted light transmitted through the resin material is measured. With a luminescent color measurement process
The protrusion forming step includes
8. The method of manufacturing an LED light source according to claim 7, wherein the plurality of protrusions are formed on the surface of the sealing portion based on the measurement result of the emission color in the emission color measurement step. The protrusion forming step includes
By using a transfer part in which a plurality of circumferential grooves are formed on one end surface of the cylindrical shape, the resin material before curing containing the second color conversion material is attached to the plurality of grooves, The method for producing an LED light source according to claim 8, wherein the adhered resin material is transferred to a surface of the sealing portion.

Images