JP2018166199A - Pseudo white series led device and silicone cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pseudo white series LED light emission device in which the occurrence of chromaticity variation (color shading) caused by a light distribution angle is suppressed, and a silicone rubber cap.SOLUTION: The pseudo white series LED comprises: a blue LED device comprising a blue LED element, a package member with a convex part housing the blue LED element, and a transparent resin sealing member sealing the blue LED element housed in the convex part and forming a light emission surface; and a silicone cap covered on the blue LED device so as to coat the light emission surface. The silicone cap includes a YAG series phosphor, a light diffusion material, and a silicone polymer, and includes a direction in which a chromaticity difference of a x value and a y value of a chromaticity coordinate (x,y) of a XYZ color system becomes 0.06 or less in any direction in a X axis and a Y axis in a whole range of 90 to 90-degree of a light distribution angle.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pseudo white LED device and a silicone cap.

  A pseudo white LED device is known in which blue light from a blue light emitting diode (blue LED element) is converted to yellow with a YAG phosphor such as a YAG: Ce phosphor, and the color is adjusted by mixing blue light and yellow light. ing. In the pseudo-white LED device, a phosphor containing YAG phosphor dispersed in a transparent encapsulant that seals the blue LED or YAG phosphor dispersed so as to cover the light emitting surface of the blue LED element is contained. A configuration is adopted in which a part of blue light is converted into yellow light by arranging a sheet.

  Since the light emitted from the blue LED element included in the blue LED device is highly directional light, the light source is conspicuous and the burden on the eyes is increased.

  A pseudo white LED device in which a blue rubber LED device is covered with a silicone rubber cap containing a YAG phosphor so as to cover its light emitting surface is already known. For example, Patent Document 1 below discloses a pseudo white LED device in which a blue LED device is provided with a silicone cap that is a molded body of silicone rubber containing a YAG phosphor.

JP 2008-252119 A

  In the case of a pseudo white LED device in which a cap that is a molded body of a silicone polymer such as silicone rubber or silicone resin containing a YAG phosphor is added to a conventional blue LED device, the directivity of light emission is still high. In addition, the blue light of the blue LED element and the yellow fluorescence of the YAG-based phosphor are color-separated, resulting in a color unevenness in which the chromaticity varies depending on the light distribution angle.

  An object of the present invention is to provide a pseudo white LED device and a silicone cap in which unevenness in chromaticity due to a light distribution angle is suppressed.

  One aspect of the present invention provides a blue LED element, a package member that includes a concave portion that accommodates the blue LED element, and a transparent resin sealing material that seals the blue LED element accommodated in the concave portion to form a light emitting surface. An LED device and a silicone cap that covers the light emitting surface of the blue LED device are provided. The silicone cap includes a YAG phosphor, a light diffusing material, and a silicone polymer, and a light distribution angle of −90 to 90 °. In the entire range, the chromaticity difference between the x value and the y value of the chromaticity coordinates (x, y) of the XYZ color system has a direction in which both the X axis direction and the Y axis direction are 0.06 or less. This is a white LED device. According to such a pseudo white LED device, it is possible to obtain a pseudo white LED device that suppresses the occurrence of a chromaticity difference depending on the light distribution angle.

  In addition, in the pseudo white LED device, it is preferable that the half-value angle of the emitted light has a direction in which both the X-axis direction and the Y-axis direction are 135 ° or more from the viewpoint of excellent light diffusibility.

  In addition, the silicone cap includes an emission surface that transmits and emits light emitted from the light emitting surface, and the emission surface includes a three-dimensional curved surface that is a flat surface, a convex surface, a concave surface, or a combination thereof. This is preferable from the viewpoint that diffusibility can be improved and uneven color can be suppressed.

  The X axis is in the major axis direction of the blue LED device, the Y axis is an axis orthogonal to the X axis, and further includes the X axis and the Z axis perpendicular to the Y axis, and the emission surface includes the Z axis. In the cross section, it includes a solid curved surface having a concave curve on the X axis and a convex curve on the Y axis, and the half-value angle of the emitted light is 155 ° or more in the X axis direction and 185 ° in the Y axis direction. The above is preferable.

  The X axis is in the direction of the long axis of the blue LED device, the Y axis is an axis orthogonal to the X axis, the exit surface includes a convex surface, and the half-value angle of the emitted light is 135 ° in the X axis direction. As described above, it is preferably 165 ° or more in the Y-axis direction.

  Further, the X axis is in the direction of the long axis of the blue LED device, the Y axis is an axis orthogonal to the direction of the X axis, and when the exit surface includes a plane, the half-value angle of the emitted light is 145 in the X axis direction. It is preferably at least 185 ° in the direction of the Y-axis.

  The X axis is in the direction of the long axis of the blue LED device, the Y axis is an axis orthogonal to the X axis, and further includes an X axis and a Z axis perpendicular to the Y axis. The surface facing the surface is a flat surface and the central thickness on the Z-axis is 0.7 to 1.5 mm, because light is diffusely reflected in the silicone cap sheet to sufficiently mix the colors. It is preferable from the point which can suppress the color nonuniformity of incident light. In the case where the emission surface includes a flat surface, the thickness of the flat surface portion is the same as that of the central portion.

  Moreover, it is preferable from containing the light-diffusion material of 2-20 mass parts with respect to 100 mass parts of silicone polymers from the point which can fully improve light diffusibility with a light-diffusion material.

  Another aspect of the present invention is a package member including a blue LED element and a concave portion that accommodates the blue LED element, and a transparent resin sealing material that seals the LED element accommodated in the concave portion to form a light emitting surface. A silicon cap including at least a YAG-based phosphor, a light diffusing material, and a silicone polymer, which covers a light emitting surface of a blue LED device including the light emitting device, wherein the light emitted from the light emitting surface is transmitted and emitted. The silicone cap includes a surface, and the exit surface includes a three-dimensional curved surface formed by a flat surface, a convex surface, a concave surface, or a combination thereof. By covering such a silicone cap on the light emitting surface of the blue LED device, it is possible to obtain a pseudo white LED device that suppresses the occurrence of color unevenness in which the chromaticity varies depending on the light distribution angle.

  ADVANTAGE OF THE INVENTION According to this invention, the pseudo | simulation white type | system | group LED device which suppressed that a chromaticity difference arises with a light distribution angle is obtained.

FIG. 1 is a schematic cross-sectional view illustrating a pseudo white LED device 10 according to the first embodiment. 2A and 2B are schematic views of the silicone cap 9 of the pseudo white LED device 10, wherein FIG. 2A is a perspective view, FIG. 2B is a top view, FIG. 2C is a front view, and FIG. FIG. 3 is a schematic cross-sectional view illustrating the pseudo white LED device 20 according to the second embodiment. 4A and 4B are schematic views of the silicone cap 19 of the pseudo white LED device 20, wherein FIG. 4A is a perspective view, FIG. 4B is a top view, FIG. 4C is a front view, and FIG. FIG. 5 is a schematic cross-sectional view illustrating a pseudo white LED device 30 according to the third embodiment. 6A and 6B are schematic views of the silicone cap 29 of the pseudo white LED device 30. FIG. 6A is a perspective view, FIG. 6B is a top view, FIG. 6C is a front view, and FIG. FIG. 7 shows the optical characteristics of the pseudo white LED device of Example 1. FIG. 8 shows the optical characteristics of the pseudo white LED device of Example 2. FIG. 9 shows the optical characteristics of the pseudo white LED device of Example 3. FIG. 10 shows the optical characteristics of the pseudo white LED device of Example 4. FIG. 11 shows the optical characteristics of the pseudo white LED device of Example 5. FIG. 12 shows optical characteristics of the pseudo white LED device of Example 6. FIG. 13 shows the optical characteristics of the pseudo white LED device of Comparative Example 1. FIG. 14 shows the optical characteristics of the pseudo white LED device of Comparative Example 2. FIG. 15 shows the optical characteristics of the pseudo white LED device of Comparative Example 3. FIG. 16 shows the optical characteristics of the pseudo white LED device of Comparative Example 4. FIG. 17 shows the optical characteristics of the pseudo white LED device of Comparative Example 5.

  Embodiments of a pseudo white LED device according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view illustrating a pseudo white LED device 10 according to the first embodiment. The pseudo white LED device 10 is a structure formed so as to cover the light emitting surface L of the blue LED device 5 with a silicone cap 9. The blue LED device 5 includes a blue LED element 2 and a transparent resin seal that forms a light emitting surface L by sealing the package member 1 including the concave portion C that accommodates the blue LED element 2 and the blue LED element 2 accommodated in the concave portion C. A blue LED device 5 including a stopper 4 is provided. The silicone cap 9 includes an emission surface P that transmits and emits light emitted from the light emitting surface L.

  2A and 2B are schematic views of the silicone cap 9 of the pseudo white LED device 10, wherein FIG. 2A is a perspective view, FIG. 2B is a top view, FIG. 2C is a front view, and FIG.

  As shown in FIG. 2, the silicone cap 9 of the present embodiment has a shape for covering a blue LED device having a rectangular package shape, for example, and a major axis direction corresponding to the X-axis direction when viewed from the upper surface And a minor axis direction corresponding to the Y axis direction orthogonal to the X axis direction. Here, for convenience of explanation, the center of the package member viewed from the top surface is defined as the intersection of the X axis and the Y axis as the origin, and the axis perpendicular to the X axis and Y axis from the origin is defined as the Z axis. By placing the origin on the surface where the silicone cap contacts the package member, the X-axis, Y-axis, and Z-axis of the silicone cap can be determined. The exit surface P corresponding to the upper surface of the silicone cap 9 includes a solid curved surface including a concave curve on the X axis and a convex curve on the Y axis in a cross section including the Z axis. Thus, by forming so that a solid curved surface may be included, light diffusibility improves and it is suppressed that a chromaticity difference arises with a light distribution angle.

  The blue LED device 5 includes a blue LED element 2, a package member 1 including a concave portion C that accommodates the blue LED element 2, and a transparent resin sealing material 4 that seals the blue LED element 2 accommodated in the concave portion C. Prepare. A reflective film such as silver plating may be formed on the inner surface of the recess C. One electrode of the blue LED element 2 is connected to the lead 1a, the other electrode of the blue LED element 2 is wire-bonded by the gold wire 3 and connected to the lead 1b, and the leads 1a and 1b are extended to the outside. ing. In such a blue LED device 5, the upper surface of the transparent resin sealing material 4 becomes the light emitting surface L. The shape of the package member 1 as viewed from above is a rectangular shape such as a square shape or a rectangular shape, but may be other shapes. The blue LED device 5 includes an LED device that emits light obtained by wavelength-converting part of light emitted from the blue LED element.

  The blue LED element 2 emits light having a peak wavelength in a blue region of 420 nm to 470 nm. And the transparent resin sealing material 4 seals and seals the blue LED element 2 accommodated in the recess C. Examples of the transparent resin forming the transparent resin sealing material include a silicone resin and an epoxy resin. In particular, a silicone resin is preferable because it is excellent in light transmittance and yellowing resistance due to heat.

  In the pseudo white LED device 10, the YAG phosphor 7 and the light diffusing material 8 are dispersed in a silicone polymer 6 such as silicone rubber or silicone resin, and the silicone cap 9 formed into a cap shape emits blue light. The color is converted so as to convert the wavelength so as to emit pseudo white light. Silicone polymers are preferable from the viewpoint that yellowing over time is suppressed even when a high-power LED device is used.

  The silicone cap 9 includes a YAG phosphor 7 as a phosphor. Further, in addition to the YAG phosphor 7, a target emission color (for example, daylight color, day white, white, warm white, or light bulb color) is used. In addition, other phosphors may be contained.

Specific examples of the YAG phosphor include, for example, Y _{3 -X} Gd _X Al ₅ O ₁₂ : Ce (0 ≦ x ≦ 3) (YAG: Ca), and an yttrium aluminate phosphor (YAG). System phosphor). Other phosphors include, for example, silicate green phosphors, aluminate green phosphors, green phosphors such as sialon green phosphors such as β-SiAlON: Eu, nitride red phosphors, Examples thereof include a silicate red phosphor, a cousin red phosphor such as CaAlSiN ₃ : Eu, a sialon red phosphor, and the like.

The light diffusing material 8 is particles that diffusely reflect light. Specific examples of the light diffusing material include particles of calcium carbonate, silica, titanium oxide, zinc sulfide, zinc oxide, alumina, magnesium oxide, barium sulfate, and the like. These may be used alone or in combination of two or more. Among these, calcium carbonate particles are preferable from the viewpoint of excellent light reflectivity. The particle size of the light diffusing material is not particularly limited, but is preferably about 4.0 to 6.0 μm in average particle size. The average particle size can be determined as a mass average value D ₅₀ in the particle size distribution measurement by laser diffraction method (or median diameter).

  The content ratio of the light diffusing material in the silicone cap 9 is 2 to 20 parts by mass, and further 5 to 10 parts by mass with respect to 100 parts by mass of the silicone polymer. It is preferable from the point of being suppressed.

  When the exit surface of the silicone cap includes a three-dimensional curved surface having a concave curve on the X axis and a convex curve on the Y axis, as in the pseudo white LED device 10 The light diffusibility is excellent such that the half-value angle of the emitted light is 155 ° or more in the X-axis direction, more preferably 160 ° or more, and 185 ° or more in the Y-axis direction perpendicular to the direction, and further 190 ° or more. A pseudo white LED device in which the occurrence of a chromaticity difference due to the light distribution angle is suppressed is obtained.

  FIG. 3 is a schematic cross-sectional view illustrating the pseudo white LED device 20 according to the second embodiment. The pseudo white LED device 20 is a structure formed so as to cover the light emitting surface of the blue LED device 5 with a silicone cap 19. The blue LED device 5 is the same as that used in the pseudo white LED device 10. The silicone cap 19 includes an emission surface R that transmits and emits light emitted from the light emitting surface. The exit surface R includes a solid curved surface having a convex surface such as a dome shape.

  4A and 4B are schematic views of the silicone cap 19, wherein FIG. 4A is a perspective view, FIG. 4B is a top view, FIG. 4C is a front view, and FIG. 4D is a right view. As described above, the light diffusibility can be improved and the occurrence of the chromaticity difference due to the light distribution angle can be suppressed by forming the output surface into a convex three-dimensional curved surface like a dome shape. The silicone cap 19 of this embodiment has a shape for covering a blue LED device having a rectangular package shape, for example, and in a cross section including the Z axis, the convex curve on the X axis is more curved than the convex curve on the Y axis. Preferably has a small curve.

  When the exit surface R of the silicone cap 19 includes a convex three-dimensional curved surface such as a dome like the pseudo white LED device 20, the half-value angle of the emitted light is 135 ° or more in the X-axis direction, It is preferably 140 ° or more and 165 ° or more, more preferably 170 ° or more in the Y-axis direction orthogonal to the direction. By having such a half-value angle of the emitted light, a pseudo white LED device having excellent light diffusibility and a small chromaticity difference due to the emitted angle can be obtained.

  FIG. 5 is a schematic cross-sectional view illustrating a pseudo white LED device 30 according to the third embodiment. The pseudo white LED device 30 is a structure formed so as to cover the light emitting surface of the blue LED device 5 with a silicone cap 29. The blue LED device 5 is the same as that used in the pseudo white LED device 10. The silicone cap 29 includes an emission surface Q that transmits and emits light emitted from the light emitting surface. The exit surface Q is a flat surface on a thick sheet that is formed to be significantly thicker than a conventional silicone cap.

  6A and 6B are schematic views of the silicone cap 29, where FIG. 6A is a perspective view, FIG. 6B is a top view, FIG. 6C is a front view, and FIG. In this way, the thickness of the silicone cap part with the exit surface facing the light-emitting surface is made to be significantly thicker, and by making it a flat surface, the light diffusibility is also improved. Moreover, color unevenness can be suppressed.

  As shown in FIG. 5, the thickness t1 of the exit surface Q of the silicone cap 29 (that is, the thickness between the entrance surface (back surface) of the central part including the Z axis of the silicone cap 29 and the exit surface) is the LED. It is formed to be significantly thicker than the thickness t2 of the peripheral ear portion that forms a recess into which the device is inserted and has a function of gripping the side wall of the LED device. Moreover, it is formed much thicker than the thickness of the portion forming the exit surface in the flat type silicone cap in which the conventional exit surface is planar. Thus, by making the thickness of the portion that becomes the exit surface extremely thicker than the thickness of the other portions, the light diffusibility is improved and the light distribution angle is also widened. Further, the occurrence of a chromaticity difference due to the light distribution angle is also suppressed. As shown in FIG. 5, when the silicone cap 29 having a thicker t1 than the t2 is used, the number of times of light reflection / scattering is increased inside the sheet, and the color mixing property and the light diffusibility are further improved. The diffused light can be emitted also from the side surface. Thereby, the light distribution angle can be further increased. The thickness t1 of the portion including the emission surface Q formed extremely thick as described above is preferably 0.7 to 1.5 mm, more preferably 0.7 to 0.9 mm. Moreover, it is 2-5 times compared with the thickness t2 of the surrounding ear | edge part which has a role which hold | grips the side wall of an LED apparatus, Furthermore, it is preferable that it is 2-3 times. When t1 is too thick, there is a tendency that a chromaticity difference is likely to occur depending on the light distribution angle. The chromaticity difference due to the light distribution angle is considered to be due to the difference in the optical path length between the light of each wavelength due to the reflection by the front and back surfaces of the silicone cap 29, and the light is split. Therefore, when it is too thick, the chromaticity difference due to the light distribution angle tends to increase. Note that a conventional silicone cap having a flat emission surface has a flat emission surface, and the thickness thereof is generally about 0.25 to 0.35 mm, and is a substantially uniform thickness as a whole. The thickness t2 of the peripheral ear of this type of conventional silicone cap is about 0.2 to 0.3 mm. (Note that the thickness t1 of the central portion including the Z-axis and the thickness t2 of the peripheral ear used in FIG. 5 have different values of t1 and t2 as dimensions of corresponding positions in other shapes of silicone caps. Can be used.)

  When the emission surface of the silicone cap includes a plane that is formed to be extremely thick like the pseudo white LED device 30, the half-value angle of the emitted light is 145 ° or more in the X-axis direction, further 150 ° or more, In the Y-axis direction orthogonal to the direction, it is preferably 185 ° or more, more preferably 190 ° or more, and a pseudo white LED device having excellent light diffusibility and a small chromaticity difference due to the emission angle can be obtained.

  The pseudo white LED devices 10, 20, and 30 of the present embodiment control the shape of the light emitting surface of the silicone cap like the silicone caps 9, 19, and 29, respectively, and the light diffusing material included in each silicone cap. As described later, the chromaticity difference between the x value and the y value of the chromaticity coordinates (x, y) of the XYZ color system in the whole range of the light distribution angle of −90 to 90 ° by the combination control of the content of Is a pseudo white LED having a small chromaticity difference in a wide range of light distribution angles such that the X-axis direction and the Y-axis direction both have a direction of 0.06 or less, preferably 0.05 or less. An apparatus can be realized.

  The emission color in the pseudo white LED device of the present embodiment includes, for example, a daylight color, a day white color, a white color, a warm white color, or a light bulb color that is toned with a YAG phosphor. More specifically, in the chromaticity coordinates (x, y) of the XYZ color system, the x value is in the range of 0.13 to 0.65 and the y value is in the entire range of the light distribution angle of −90 to 90 °. What is contained in the range of 0.07-0.65 is preferable. According to such a quasi-white LED device, it is possible to realize a quasi-white LED device that has a small chromaticity difference depending on the light distribution angle and suppresses occurrence of color unevenness.

  Hereinafter, the present invention will be described more specifically with reference to examples. The scope of the present invention is not limited by the examples.

[Production Example 1]
2 parts by mass of YAG: Ce phosphor having a fluorescence peak wavelength at 550 nm and 20 parts by mass of calcium carbonate having an average particle diameter of 5.0 μm as a light diffusing material are mixed and kneaded with 100 parts by mass of thermosetting silicone rubber. The phosphor-containing resin composition was obtained by kneading using a machine. The obtained phosphor-containing resin composition was filled in a mold, heat-treated at 165 to 170 ° C., and thermally cured to obtain a phosphor-containing sheet. A silicone rubber cap having a shape as shown in FIG. 2 was formed on the phosphor sheet. And each silicone rubber cap in a fluorescent substance sheet was cut | disconnected and separated into pieces, and silicone rubber cap A2 was manufactured. The silicone rubber cap A2 has a top surface of 2.4 mm × width 1.76 mm, a back surface of the silicone rubber cap A2, and a thickness t1 of a central portion including the Z axis is 0.8 mm, in a cross section including the Z axis and the X axis. The height difference of the curve on the exit surface was 0.13 mm, and the thickness t2 of the peripheral ear was about 0.2 mm.

[Production Example 2]
A silicone rubber cap B2 was produced in the same manner as in Production Example 1 except that a phosphor-containing sheet having the shape of a silicone rubber cap having the shape shown in FIG. The silicone rubber cap B2 has an upper surface of 2.6 mm in length and 1.86 mm in width, a rear surface of the convex surface is a flat surface, a thickness t1 of the central portion of the convex surface including the Z axis is 0.8 mm, and a thickness of the peripheral ear portion The thickness t2 was about 0.2 mm.

[Production Example 3]
A silicone rubber cap C2 was produced in the same manner as in Production Example 1 except that a phosphor-containing sheet having a silicone rubber cap having a shape as shown in FIG. The silicone rubber cap C2 has an upper surface of 2.4 mm long × 1.76 mm wide, a flat emission surface, a thickness t1 of the central portion including the Z axis is 0.8 mm, The thickness t2 was about 0.2 mm.

[Production Examples 4 to 6]
In Production Examples 1 to 3, instead of mixing 20 parts by mass of calcium carbonate, silicone rubber cap A1, silicone rubber cap B1, and silicone rubber cap C1 were respectively prepared except that 10 parts by mass of calcium carbonate was mixed. Manufactured.

[Production Examples 7 to 9]
In Production Examples 1 to 3, silicone rubber cap A0, silicone rubber cap B0, and silicone rubber cap C0 were produced in the same manner except that calcium carbonate was not added instead of mixing 20 parts by mass of calcium carbonate. did.

[Production Example 10]
With 0 parts by mass of calcium carbonate including the shape of a silicone rubber cap having the same shape except that the thickness of 0.8 mm at the center including the Z-axis of the exit surface of the silicone rubber cap C0 is changed to 0.3 mm. Except for producing a certain phosphor-containing cap sheet, a silicone rubber cap D0 corresponding to a conventional flat type having a flat emission surface was produced by the same method as in Production Example 1.

[Production Example 11]
A phosphor containing 20 parts by mass of calcium carbonate, including the shape of a silicone rubber cap having the same shape except that the thickness of 0.8 mm at the center including the Z-axis of the silicone rubber cap C2 is changed to 0.3 mm. A silicone rubber cap D2 corresponding to a conventional flat type having a flat emission surface was produced by the same method as in Production Example 1 except that the sheet was produced.

[Examples 1-6, Comparative Examples 1-5]
A surface-mounted blue LED device (Nichia Corporation) with a rectangular package size of 2.2 x 1.4 x 0.7 (mm) and chromaticity coordinates xy (0.133, 0.075) ) NESB146A) manufactured by Then, each of the silicone rubber caps A2 to C2, A1 to C1, A0 to C0, D0, and D2 obtained in Production Examples 1 to 11 is covered with a blue LED device so as to cover the light emitting surface, and silicone-based adhesion is performed. A pseudo white LED device was manufactured by bonding via an agent. And about each pseudo white LED device, the light distribution angle and the light distribution chromaticity were measured with the following method. Examples using silicone rubber caps A2, A1, B2, B1, C2 and C1 are Examples 1 to 6, respectively, and those using silicone rubber caps D0, D2, A0, B0 and C0 are respectively compared. Examples 1-6. The results are shown in Table 1 and FIGS.

[Measurement of chromaticity difference by light distribution angle]
A current set to 20 mA was passed through each pseudo white LED device, light was emitted in a dark box, and measurement was performed using a receiving optical fiber connected to a spectroscope. Then, for each of the x value and the y value, the chromaticity at a light distribution angle in the range of −90 to 90 ° was measured. A value obtained by subtracting the minimum value from the maximum value for each of the x value and the y value was defined as the chromaticity difference. The chromaticity is measured in each of the X-axis and Y-axis directions with respect to the center of the rectangular package, and the X-axis chromaticity difference and the Y-axis chromaticity difference are obtained. Was calculated for each of the x and y values. The measurement in each direction of the X axis and the Y axis is performed by setting the cathode side of the polarity on the right side and setting the lighting jig. In the notation of the X axis and the Y axis shown in FIGS. In the axis, measurement is performed from the side not described as “X-axis” to the side described as “X-axis” (from −90 ° to 90 °), and in the Y-axis, “Y-axis” is measured. Measurement was performed from the side not described as “Y axis” toward the side described as “Y axis” (from 90 ° to −90 °).

[Measurement of half-value angle]
A current set to 20 mA was passed through each pseudo white LED device, light was emitted in a dark box, and measurement was performed using a receiving optical fiber connected to a spectroscope. And the emitted light intensity was measured in the range of -100-100 degrees. The light emission intensity is measured by aligning the Z-axis with the center of the top rectangular package, taking the X-axis parallel to the long side and the Y-axis parallel to the short side. These three axes are orthogonal to each other and the XY axis is silicone. In accordance with the back surface of the rubber cap, the X axis and Y axis directions with respect to the intersection were measured. The measurement in each direction of the X axis and the Y axis is performed by setting the cathode side of the polarity on the right side and setting the lighting jig. In the notation of the X axis and the Y axis shown in FIGS. In the axis, measurement is performed from the side not described as “X-axis” to the side described as “X-axis” (from −90 ° to 90 °), and in the Y-axis, “Y-axis” is measured. Measurement was performed from the side not described as “Y axis” toward the side described as “Y axis” (from 90 ° to −90 °).

  From the results in Table 1, the exit surface of the silicone rubber cap is a three-dimensional curved surface having a concave curve on the X axis and a convex curve on the Y axis in the cross section including the Z axis as in Examples 1-2. As shown in Examples 3 to 4, the exit surface is formed into a dome-shaped solid curved surface, or the exit surface is made thick as in Examples 5 to 6, and a predetermined amount of light diffusing material is blended, thereby providing a light distribution angle − In the entire range of 90 to 90 °, the chromaticity difference between the x value and the y value of the chromaticity coordinates (x, y) of the XYZ color system is 0.06 or less, and the chromaticity difference due to the light distribution angle is A suppressed pseudo-white LED device was obtained. On the other hand, the quasi-white LED device in which the emission surface is obtained in Comparative Examples 1 and 2 has a chromaticity difference between the x value and the y value larger than those in Examples 1 to 6, and the chromaticity difference due to the light distribution angle is small. A large pseudo white LED was emitted. Further, in the cross section including the Z-axis as in Comparative Examples 3, 4 and 5, a solid curved surface having a concave curve on the X-axis and a convex curve on the Y-axis, a dome-shaped solid curved surface, Even when the thickness was increased, when the light diffusing material was not blended, the chromaticity difference due to the light distribution angle was not suppressed.

DESCRIPTION OF SYMBOLS 1 Package member 1a, 1b Lead 2 Blue LED element 3 Gold wire 4 Transparent resin sealing material 5 Blue LED device 6 Silicone 7 YAG type phosphor 8 Light diffusing material 9, 19, 29 Silicone cap 10, 20, 30 Pseudo white type LED device C Recess P, R, Q Emission surface L Emission surface

  The present invention relates to a pseudo white LED device and a silicone cap.

  A pseudo white LED device is known in which blue light from a blue light emitting diode (blue LED element) is converted to yellow with a YAG phosphor such as a YAG: Ce phosphor, and the color is adjusted by mixing blue light and yellow light. ing. In the pseudo-white LED device, a phosphor containing YAG phosphor dispersed in a transparent encapsulant that seals the blue LED or YAG phosphor dispersed so as to cover the light emitting surface of the blue LED element is contained. A configuration is adopted in which a part of blue light is converted into yellow light by arranging a sheet.

  Since the light emitted from the blue LED element included in the blue LED device is highly directional light, the light source is conspicuous and the burden on the eyes is increased.

  A pseudo white LED device in which a blue rubber LED device is covered with a silicone rubber cap containing a YAG phosphor so as to cover its light emitting surface is already known. For example, Patent Document 1 below discloses a pseudo white LED device in which a blue LED device is provided with a silicone cap that is a molded body of silicone rubber containing a YAG phosphor.

JP 2008-252119 A

  In the case of a pseudo white LED device in which a cap that is a molded body of a silicone polymer such as silicone rubber or silicone resin containing a YAG phosphor is added to a conventional blue LED device, the directivity of light emission is still high. In addition, the blue light of the blue LED element and the yellow fluorescence of the YAG-based phosphor are color-separated, resulting in a color unevenness in which the chromaticity varies depending on the light distribution angle.

  An object of the present invention is to provide a pseudo white LED device and a silicone cap in which unevenness in chromaticity due to a light distribution angle is suppressed.

One aspect of the invention, a blue LED element, a rectangular package member when viewed from the top Ru with a recess for accommodating the blue LED element, sealing the blue LED element housed in the recess emission blue LED equipment comprising a transparent resin encapsulant to form a surface, the, and, equipped with a silicone cap that is put to cover the light emitting surface to blue LED device, the silicone cap, emission surface covering the light emitting surface The exit surface region includes at least a thick portion having a thickness of 0.7 to 1.5 mm, and the silicone cap includes a YAG phosphor, a light diffusing material, and a silicone polymer, and 100 parts by mass of the silicone polymer. 2-20 parts by mass of the light diffusing material with respect to the light emitting surface, the origin of which is the center of the rectangle, the X axis in the major axis direction of the rectangle, and the Y axis perpendicular to the X axis in the minor axis direction are set. , The direction perpendicular to the X and Y axes When the Z axis is the Z axis, the positive direction of the Z axis is the light distribution angle of 0 °, the X axis and the Y axis direction both in the light distribution angle of −90 to 90 °, the difference between the maximum value and the minimum value of Sa及 beauty y value between the maximum value and the minimum value of the x values of the XYZ color system chromaticity coordinates (x, y), nothing Re also be under 0.06 or less , the emitted light is white LED device pseudo- having half angle is 135 ° or more in either direction of the direction and the Y-axis of the X-axis. According to such a pseudo white LED device, it is possible to obtain a pseudo white LED device that suppresses the occurrence of a chromaticity difference depending on the light distribution angle . By having a thick portion with a wall thickness of 0.7 to 1.5 mm, uneven color of the emitted light can be suppressed by causing light to diffusely reflect within the silicone cap sheet to sufficiently mix the colors. . Note that the thickness is uniform when the emission surface includes a flat surface. Moreover, containing 2-20 mass parts of light diffusing material with respect to 100 mass parts of silicone polymer can fully improve light diffusibility with a light diffusing material.

The silicone cap has a peripheral region that abuts the side surface of the package member around the emission surface region, and the thickness t2 of the peripheral region is 1/5 to 1/1 of the thickness t1 of the output surface region on the Z axis. 2 is preferable.

Further, out morphism surface area, planar, convex, include a concave or solid surfaces by a combination thereof, or to improve a light diffusing property by the shape of the silicone cap, from the viewpoint of color unevenness may or suppressed.

Further, out morphism surface area, in a cross-section including the Z-axis, has a concave curve on the X-axis, it comprises a three-dimensional curved surface having a convex curve on the Y axis, outgoing light 155 ° in the direction of the X axis above, and this having a der Ru half angle 185 ° or more in the direction of the Y axis are preferred.

Further, out morphism surface region comprises a convex surface, at 1 35 ° or more in the way direction outgoing light of the X axis, and this having a half-value angle is 1 65 ° or more in the Y-axis direction is preferable.

Further, out morphism surface region comprises a planar emitted light is X-axis Direction with 145 ° or more, and preferably this has a Der Ru half angle 185 ° or more Y-axis Direction.

Further, another aspect of the present invention, the light emitting surface of the LED element housed in a rectangular package member and the recess is sealed when viewed Ru with a recess for accommodating the blue LED element and the blue LED element the blue LED equipment and a transparent resin encapsulant to form, is put to cover the light emission surface, and at least including silicone cap and a silicone polymer YAG phosphor and a light diffusion material, the light emitting surface look including an emission surface area of not transmit light emitted by emanating from exit surface region comprises at least the thick portion of the thick 0.7 to 1.5 mm, 2 to 20 mass relative to 100 parts by weight of silicone polymer containing the light diffusion material parts, out morphism surface region is a silicone cap that includes planar, convex, concave or solid surfaces by combinations thereof. By covering such a silicone cap on the light emitting surface of the blue LED device, it is possible to obtain a pseudo white LED device that suppresses the occurrence of color unevenness in which the chromaticity varies depending on the light distribution angle.

  The center of the rectangle on the light emitting surface is the origin, the X axis is set in the major axis direction of the rectangle, the Y axis perpendicular to the X axis is set in the minor axis direction, and the axis orthogonal to the X axis and the Y axis is set as the Z axis. In this case, there is a peripheral region in contact with the side surface of the package member around the exit surface region, and the thickness t2 of the peripheral region is 1/5 to 1/2 of the thickness t1 on the Z axis of the exit surface region. Is preferred.

  ADVANTAGE OF THE INVENTION According to this invention, the pseudo | simulation white type | system | group LED device which suppressed that a chromaticity difference arises with a light distribution angle is obtained.

FIG. 1 is a schematic cross-sectional view illustrating a pseudo white LED device 10 according to the first embodiment. 2A and 2B are schematic views of the silicone cap 9 of the pseudo white LED device 10, wherein FIG. 2A is a perspective view, FIG. 2B is a top view, FIG. 2C is a front view, and FIG. FIG. 3 is a schematic cross-sectional view illustrating the pseudo white LED device 20 according to the second embodiment. 4A and 4B are schematic views of the silicone cap 19 of the pseudo white LED device 20, wherein FIG. 4A is a perspective view, FIG. 4B is a top view, FIG. 4C is a front view, and FIG. FIG. 5 is a schematic cross-sectional view illustrating a pseudo white LED device 30 according to the third embodiment. 6A and 6B are schematic views of the silicone cap 29 of the pseudo white LED device 30. FIG. 6A is a perspective view, FIG. 6B is a top view, FIG. 6C is a front view, and FIG. FIG. 7 shows the optical characteristics of the pseudo white LED device of Example 1. FIG. 8 shows the optical characteristics of the pseudo white LED device of Example 2. FIG. 9 shows the optical characteristics of the pseudo white LED device of Example 3. FIG. 10 shows the optical characteristics of the pseudo white LED device of Example 4. FIG. 11 shows the optical characteristics of the pseudo white LED device of Example 5. FIG. 12 shows optical characteristics of the pseudo white LED device of Example 6. FIG. 13 shows the optical characteristics of the pseudo white LED device of Comparative Example 1. FIG. 14 shows the optical characteristics of the pseudo white LED device of Comparative Example 2. FIG. 15 shows the optical characteristics of the pseudo white LED device of Comparative Example 3. FIG. 16 shows the optical characteristics of the pseudo white LED device of Comparative Example 4. FIG. 17 shows the optical characteristics of the pseudo white LED device of Comparative Example 5.

  Embodiments of a pseudo white LED device according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view illustrating a pseudo white LED device 10 according to the first embodiment. The pseudo white LED device 10 is a structure formed so as to cover the light emitting surface L of the blue LED device 5 with a silicone cap 9. The blue LED device 5 includes a blue LED element 2 and a transparent resin seal that forms a light emitting surface L by sealing the package member 1 including the concave portion C that accommodates the blue LED element 2 and the blue LED element 2 accommodated in the concave portion C. A blue LED device 5 including a stopper 4 is provided. The silicone cap 9 includes an emission surface P that transmits and emits light emitted from the light emitting surface L.

  2A and 2B are schematic views of the silicone cap 9 of the pseudo white LED device 10, wherein FIG. 2A is a perspective view, FIG. 2B is a top view, FIG. 2C is a front view, and FIG.

As shown in FIG. 2, the silicone cap 9 in this embodiment has a shape to be put on a blue LED device of rectangle package shape when viewed from above, a rectangular center when viewed from above the origin, having a minor radius direction countercurrent Metropolitan corresponding to the Y-axis direction perpendicular to the major axis direction and the X-axis direction corresponding to the X-axis direction. Here, for convenience of explanation, the center of the package member viewed from the top surface is defined as the intersection of the X axis and the Y axis as the origin, and the axis perpendicular to the X axis and Y axis from the origin is defined as the Z axis. By placing the origin on the surface where the silicone cap contacts the package member, the X-axis, Y-axis, and Z-axis of the silicone cap can be determined. The exit surface P corresponding to the upper surface of the silicone cap 9 includes a solid curved surface including a concave curve on the X axis and a convex curve on the Y axis in a cross section including the Z axis. Thus, by forming so that a solid curved surface may be included, light diffusibility improves and it is suppressed that a chromaticity difference arises with a light distribution angle.

The blue LED device 5 includes a blue LED element 2, a package member 1 including a concave portion C that accommodates the blue LED element 2, and a transparent resin sealing material 4 that seals the blue LED element 2 accommodated in the concave portion C. Prepare. A reflective film such as silver plating may be formed on the inner surface of the recess C. One electrode of the blue LED element 2 is connected to the lead 1a, the other electrode of the blue LED element 2 is wire-bonded by the gold wire 3 and connected to the lead 1b, and the leads 1a and 1b are extended to the outside. ing. In such a blue LED device 5, the upper surface of the transparent resin sealing material 4 becomes the light emitting surface L. The shape of the package member 1 as viewed from the upper surface, Ru rectangular der such square or rectangular shape. The blue LED device 5 includes an LED device that emits light obtained by wavelength-converting part of light emitted from the blue LED element.

  The blue LED element 2 emits light having a peak wavelength in a blue region of 420 nm to 470 nm. And the transparent resin sealing material 4 seals and seals the blue LED element 2 accommodated in the recess C. Examples of the transparent resin forming the transparent resin sealing material include a silicone resin and an epoxy resin. In particular, a silicone resin is preferable because it is excellent in light transmittance and yellowing resistance due to heat.

  In the pseudo white LED device 10, the YAG phosphor 7 and the light diffusing material 8 are dispersed in a silicone polymer 6 such as silicone rubber or silicone resin, and the silicone cap 9 formed into a cap shape emits blue light. The color is converted so as to convert the wavelength so as to emit pseudo white light. Silicone polymers are preferable from the viewpoint that yellowing over time is suppressed even when a high-power LED device is used.

  The silicone cap 9 includes a YAG-based phosphor 7 as a phosphor, and in addition to the YAG-based phosphor 7, a target emission color (for example, daylight color, day white, white, warm white, or light bulb color). In addition, other phosphors may be contained.

Specific examples of the YAG phosphor include, for example, Y _{3 -X} Gd _X Al ₅ O ₁₂ : Ce (0 ≦ x ≦ 3) (YAG: Ce) , and an yttrium aluminate phosphor (YAG). System phosphor). Other phosphors include, for example, silicate green phosphors, aluminate green phosphors, green phosphors such as sialon green phosphors such as β-SiAlON: Eu, nitride red phosphors, Examples thereof include a silicate red phosphor, a cousin red phosphor such as CaAlSiN ₃ : Eu, a sialon red phosphor, and the like.

The light diffusing material 8 is particles that diffusely reflect light. Specific examples of the light diffusing material include particles of calcium carbonate, silica, titanium oxide, zinc sulfide, zinc oxide, alumina, magnesium oxide, barium sulfate, and the like. These may be used alone or in combination of two or more. Among these, calcium carbonate particles are preferable from the viewpoint of excellent light reflectivity. The particle size of the light diffusing material is not particularly limited, but is preferably about 4.0 to 6.0 μm in average particle size. The average particle size can be determined as a mass average value D ₅₀ in the particle size distribution measurement by laser diffraction method (or median diameter).

  The content ratio of the light diffusing material in the silicone cap 9 is 2 to 20 parts by mass, and further 5 to 10 parts by mass with respect to 100 parts by mass of the silicone polymer. It is preferable from the point of being suppressed.

  When the exit surface of the silicone cap includes a three-dimensional curved surface having a concave curve on the X axis and a convex curve on the Y axis, as in the pseudo white LED device 10 The light diffusibility is excellent such that the half-value angle of the emitted light is 155 ° or more in the X-axis direction, more preferably 160 ° or more, and 185 ° or more in the Y-axis direction perpendicular to the direction, and further 190 ° or more. A pseudo white LED device in which the occurrence of a chromaticity difference due to the light distribution angle is suppressed is obtained.

  FIG. 3 is a schematic cross-sectional view illustrating the pseudo white LED device 20 according to the second embodiment. The pseudo white LED device 20 is a structure formed so as to cover the light emitting surface of the blue LED device 5 with a silicone cap 19. The blue LED device 5 is the same as that used in the pseudo white LED device 10. The silicone cap 19 includes an emission surface R that transmits and emits light emitted from the light emitting surface. The exit surface R includes a solid curved surface having a convex surface such as a dome shape.

  4A and 4B are schematic views of the silicone cap 19, wherein FIG. 4A is a perspective view, FIG. 4B is a top view, FIG. 4C is a front view, and FIG. 4D is a right view. As described above, the light diffusibility can be improved and the occurrence of the chromaticity difference due to the light distribution angle can be suppressed by forming the output surface into a convex three-dimensional curved surface like a dome shape. The silicone cap 19 of this embodiment has a shape for covering a blue LED device having a rectangular package shape, for example, and in a cross section including the Z axis, the convex curve on the X axis is more curved than the convex curve on the Y axis. Preferably has a small curve.

  When the exit surface R of the silicone cap 19 includes a convex three-dimensional curved surface such as a dome like the pseudo white LED device 20, the half-value angle of the emitted light is 135 ° or more in the X-axis direction, It is preferably 140 ° or more and 165 ° or more, more preferably 170 ° or more in the Y-axis direction orthogonal to the direction. By having such a half-value angle of the emitted light, a pseudo white LED device having excellent light diffusibility and a small chromaticity difference due to the emitted angle can be obtained.

  FIG. 5 is a schematic cross-sectional view illustrating a pseudo white LED device 30 according to the third embodiment. The pseudo white LED device 30 is a structure formed so as to cover the light emitting surface of the blue LED device 5 with a silicone cap 29. The blue LED device 5 is the same as that used in the pseudo white LED device 10. The silicone cap 29 includes an emission surface Q that transmits and emits light emitted from the light emitting surface. The exit surface Q is a flat surface on a thick sheet that is formed to be significantly thicker than a conventional silicone cap.

  6A and 6B are schematic views of the silicone cap 29, where FIG. 6A is a perspective view, FIG. 6B is a top view, FIG. 6C is a front view, and FIG. In this way, the thickness of the silicone cap part with the exit surface facing the light-emitting surface is made to be significantly thicker, and by making it a flat surface, the light diffusibility is also improved. Moreover, color unevenness can be suppressed.

As shown in FIG. 5, the thickness t1 of the exit surface Q of the silicone cap 29 (that is, the thickness between the entrance surface (back surface) of the central part including the Z axis of the silicone cap 29 and the exit surface) is the LED. It is formed to be significantly thicker than the thickness t2 of the peripheral ear portion that forms a recess into which the device is inserted and has a function of gripping the side wall of the LED device. Moreover, it is formed much thicker than the thickness of the portion forming the exit surface in the flat type silicone cap in which the conventional exit surface is planar. Thus, by making the thickness of the portion that becomes the exit surface extremely thicker than the thickness of the other portions, the light diffusibility is improved and the light distribution angle is also widened. In addition, the occurrence of a chromaticity difference due to the light distribution angle is also suppressed. As shown in FIG. 5, when the silicone cap 29 having a thicker t1 than the t2 is used, the number of times of light reflection / scattering is increased inside the sheet, and the color mixing property and the light diffusibility are further improved. The diffused light can be emitted also from the side surface. Thereby, the light distribution angle can be further increased. The thickness t1 of the portion including the exit surface Q formed extremely thick in this way is 0.7 to 1.5 mm . It is preferable that it is 7-0.9 mm. Moreover, it is 2-5 times compared with the thickness t2 of the surrounding ear | edge part which has a role which hold | grips the side wall of an LED apparatus, Furthermore, it is preferable that it is 2-3 times. When t1 is too thick, there is a tendency that a chromaticity difference is likely to occur depending on the light distribution angle. The chromaticity difference due to the light distribution angle is considered to be due to the difference in the optical path length between the light of each wavelength due to the reflection by the front and back surfaces of the silicone cap 29, and the light is split. Therefore, when it is too thick, the chromaticity difference due to the light distribution angle tends to increase. Note that a conventional silicone cap having a flat emission surface has a flat emission surface, and the thickness thereof is generally about 0.25 to 0.35 mm, and is a substantially uniform thickness as a whole. The thickness t2 of the peripheral ear of this type of conventional silicone cap is about 0.2 to 0.3 mm. (Note that the thickness t1 of the central portion including the Z-axis and the thickness t2 of the peripheral ear used in FIG. 5 have different values of t1 and t2 as dimensions of corresponding positions in other shapes of silicone caps. Can be used.)

When the emission surface area that is the emission surface of the silicone cap includes a plane that is formed extremely thick like the pseudo white LED device 30, the half-value angle of the emitted light is 145 ° or more in the X-axis direction, It is preferably 150 ° or more and 185 ° or more, more preferably 190 ° or more in the Y-axis direction orthogonal to the direction, and a pseudo white LED device having excellent light diffusibility and small chromaticity difference due to the emission angle can be obtained.

The pseudo white LED devices 10, 20, and 30 of the present embodiment control the shape of the light emitting surface of the silicone cap like the silicone caps 9, 19, and 29, respectively, and the light diffusing material included in each silicone cap. As described later, the maximum value and the minimum value of the x value of the chromaticity coordinates (x, y) of the XYZ color system in the whole range of the light distribution angle of −90 to 90 ° by the combination control of the content of 0 in both the difference X-axis direction and the Y-axis direction between the maximum value and the minimum value of Sa及 beauty y values. 06 below, ing to 0.05 Preferably, small chromaticity difference in the range of the light distribution angle in a wide range, it is possible to realize a pseudo-white LED device.

  The emission color in the pseudo white LED device of the present embodiment includes, for example, a daylight color, a day white color, a white color, a warm white color, or a light bulb color that is toned with a YAG phosphor. More specifically, in the chromaticity coordinates (x, y) of the XYZ color system, the x value is in the range of 0.13 to 0.65 and the y value is in the entire range of the light distribution angle of −90 to 90 °. What is contained in the range of 0.07-0.65 is preferable. According to such a quasi-white LED device, it is possible to realize a quasi-white LED device that has a small chromaticity difference depending on the light distribution angle and suppresses occurrence of color unevenness.

  Hereinafter, the present invention will be described more specifically with reference to examples. The scope of the present invention is not limited by the examples.

[Production Example 1]
2 parts by mass of YAG: Ce phosphor having a fluorescence peak wavelength at 550 nm and 20 parts by mass of calcium carbonate having an average particle diameter of 5.0 μm as a light diffusing material are mixed and kneaded with 100 parts by mass of thermosetting silicone rubber. The phosphor-containing resin composition was obtained by kneading using a machine. The obtained phosphor-containing resin composition was filled in a mold, heat-treated at 165 to 170 ° C., and thermally cured to obtain a phosphor-containing sheet. A silicone rubber cap having a shape as shown in FIG. 2 was formed on the phosphor sheet. And each silicone rubber cap in a fluorescent substance sheet was cut | disconnected and separated into pieces, and silicone rubber cap A2 was manufactured. The silicone rubber cap A2 has a top surface of 2.4 mm × width 1.76 mm, a back surface of the silicone rubber cap A2, and a thickness t1 of a central portion including the Z axis is 0.8 mm, in a cross section including the Z axis and the X axis. The height difference of the curve on the exit surface was 0.13 mm, and the thickness t2 of the peripheral ear was about 0.2 mm.

[Production Example 2]
A silicone rubber cap B2 was produced in the same manner as in Production Example 1 except that a phosphor-containing sheet having the shape of a silicone rubber cap having the shape shown in FIG. The silicone rubber cap B2 has an upper surface of 2.6 mm in length and 1.86 mm in width, a rear surface of the convex surface is a flat surface, a thickness t1 of the central portion of the convex surface including the Z axis is 0.8 mm, and a thickness of the peripheral ear portion The thickness t2 was about 0.2 mm.

[Production Example 3]
A silicone rubber cap C2 was produced in the same manner as in Production Example 1 except that a phosphor-containing sheet having a silicone rubber cap having a shape as shown in FIG. The silicone rubber cap C2 has an upper surface of 2.4 mm long × 1.76 mm wide, a flat emission surface, a thickness t1 of the central portion including the Z axis is 0.8 mm, The thickness t2 was about 0.2 mm.

[Production Examples 4 to 6]
In Production Examples 1 to 3, instead of mixing 20 parts by mass of calcium carbonate, silicone rubber cap A1, silicone rubber cap B1, and silicone rubber cap C1 were respectively prepared except that 10 parts by mass of calcium carbonate was mixed. Manufactured.

[Production Examples 7 to 9]
In Production Examples 1 to 3, silicone rubber cap A0, silicone rubber cap B0, and silicone rubber cap C0 were produced in the same manner except that calcium carbonate was not blended instead of mixing 20 parts by mass of calcium carbonate. did.

[Production Example 10]
With 0 parts by mass of calcium carbonate including the shape of a silicone rubber cap having the same shape except that the thickness of 0.8 mm at the center including the Z-axis of the exit surface of the silicone rubber cap C0 is changed to 0.3 mm. Except for producing a certain phosphor-containing cap sheet, a silicone rubber cap D0 corresponding to a conventional flat type having a flat emission surface was produced by the same method as in Production Example 1.

[Production Example 11]
A phosphor containing 20 parts by mass of calcium carbonate, including the shape of a silicone rubber cap having the same shape except that the thickness of 0.8 mm at the center including the Z-axis of the silicone rubber cap C2 is changed to 0.3 mm. A silicone rubber cap D2 corresponding to a conventional flat type having a flat emission surface was produced by the same method as in Production Example 1 except that the sheet was produced.

[Examples 1-6, Comparative Examples 1-5]
A surface-mounted blue LED device (Nichia Corporation) with a rectangular package size of 2.2 x 1.4 x 0.7 (mm) and chromaticity coordinates xy (0.133, 0.075) ) NESB146A) manufactured by Then, each of the silicone rubber caps A2 to C2, A1 to C1, A0 to C0, D0, and D2 obtained in Production Examples 1 to 11 is covered with a blue LED device so as to cover the light emitting surface, and silicone-based adhesion is performed. A pseudo white LED device was manufactured by bonding via an agent. And about each pseudo white LED device, the light distribution angle and the light distribution chromaticity were measured with the following method. Examples using silicone rubber caps A2, A1, B2, B1, C2 and C1 are Examples 1 to 6, respectively, and those using silicone rubber caps D0, D2, A0, B0 and C0 are respectively compared. Examples 1-6. The results are shown in Table 1 and FIGS.

[Measurement of chromaticity difference by light distribution angle]
A current set to 20 mA was passed through each pseudo white LED device, light was emitted in a dark box, and measurement was performed using a receiving optical fiber connected to a spectroscope. Then, for each of the x value and the y value, the chromaticity at a light distribution angle in the range of −90 to 90 ° was measured. A value obtained by subtracting the minimum value from the maximum value for each of the x value and the y value was defined as the chromaticity difference. The chromaticity is measured in each of the X-axis and Y-axis directions with respect to the center of the rectangular package, and the X-axis chromaticity difference and the Y-axis chromaticity difference are obtained. Was calculated for each of the x and y values. The measurement in each direction of the X axis and the Y axis is performed by setting the cathode side of the polarity on the right side and setting the lighting jig. In the notation of the X axis and the Y axis shown in FIGS. In the axis, measurement is performed from the side not described as “X-axis” to the side described as “X-axis” (from −90 ° to 90 °), and in the Y-axis, “Y-axis” is measured. Measurement was performed from the side not described as “Y axis” toward the side described as “Y axis” (from 90 ° to −90 °).

[Measurement of half-value angle]
A current set to 20 mA was passed through each pseudo white LED device, light was emitted in a dark box, and measurement was performed using a receiving optical fiber connected to a spectroscope. And the emitted light intensity was measured in the range of -100-100 degrees. The light emission intensity is measured by aligning the Z-axis with the center of the top rectangular package, taking the X-axis parallel to the long side and the Y-axis parallel to the short side. These three axes are orthogonal to each other and the XY axis is silicone. In accordance with the back surface of the rubber cap, the X axis and Y axis directions with respect to the intersection were measured. The measurement in each direction of the X axis and the Y axis is performed by setting the cathode side of the polarity on the right side and setting the lighting jig. In the notation of the X axis and the Y axis shown in FIGS. In the axis, measurement is performed from the side not described as “X-axis” to the side described as “X-axis” (from −90 ° to 90 °), and in the Y-axis, “Y-axis” is measured. Measurement was performed from the side not described as “Y axis” toward the side described as “Y axis” (from 90 ° to −90 °).

From the results of Table 1, the exit surface area of the silicone rubber cap is a solid curved surface having a concave curve on the X axis and a convex curve on the Y axis in the cross section including the Z axis as in Examples 1-2. Or the exit surface is made into a dome-shaped solid curved surface as in Examples 3 to 4, or the exit surface region is thickened as in Examples 5 to 6, and a predetermined amount of light diffusing material is blended. The chromaticity difference between the x value and y value of the chromaticity coordinates (x, y) of the XYZ color system is 0.06 or less in the entire range of angles -90 to 90 °, and the chromaticity depending on the light distribution angle A pseudo white LED device in which the difference was suppressed was obtained. On the other hand, the pseudo white LED device obtained in Comparative Examples 1 and 2 having the normal emission surface area has a chromaticity difference between the x value and the y value larger than those in Examples 1 to 6, and the light distribution Pseudo white LED light emission with a large chromaticity difference due to corners was obtained. Further, in the cross section including the Z-axis as in Comparative Examples 3, 4 and 5, a solid curved surface having a concave curve on the X-axis and a convex curve on the Y-axis, a dome-shaped solid curved surface, Even when the thickness was increased, when the light diffusing material was not blended, the chromaticity difference due to the light distribution angle was not suppressed.

DESCRIPTION OF SYMBOLS 1 Package member 1a, 1b Lead 2 Blue LED element 3 Gold wire 4 Transparent resin sealing material 5 Blue LED device 6 Silicone 7 YAG type phosphor 8 Light diffusing material 9, 19, 29 Silicone cap 10, 20, 30 Pseudo white type LED device C Recess P, R, Q Outgoing surface (outgoing surface area)
L Light emitting surface

Claims (9)

A blue LED device comprising: a blue LED element; a package member including a concave portion that accommodates the blue LED element; and a transparent resin sealing material that seals the blue LED element accommodated in the concave portion to form a light emitting surface; A blue LED device, and a silicone cap that covers the light emitting surface.
The silicone cap includes a YAG phosphor, a light diffusing material, and a silicone polymer,
The chromaticity difference between the x value and y value of the chromaticity coordinates (x, y) of the XYZ color system is either in the X-axis direction or the Y-axis direction in the entire range of the light distribution angle -90 to 90 °. The pseudo-white LED device is characterized by having a direction of 0.06 or less.   The pseudo-white LED device according to claim 1, wherein the half-value angle of the emitted light has a direction in which both the X-axis direction and the Y-axis direction are 135 ° or more. The silicone cap includes an emission surface that transmits and emits light emitted from the light emitting surface,
The pseudo-white LED device according to claim 1 or 2, wherein the emission surface includes a three-dimensional curved surface formed by a plane, a convex surface, a concave surface, or a combination thereof. The X axis is in the major axis direction of the blue LED device, the Y axis is an axis orthogonal to the X axis, and further includes the X axis and a Z axis perpendicular to the Y axis.
In the cross section including the Z axis, the exit surface includes a solid curved surface having a concave curve on the X axis and a convex curve on the Y axis, and the half-value angle of the emitted light is the direction of the X axis The quasi-white LED device according to claim 3, wherein the pseudo white LED device is at least 155 ° and at least 185 ° in the Y-axis direction. The X axis is in the direction of the long axis of the blue LED device, the Y axis is an axis orthogonal to the X axis,
4. The pseudo white LED device according to claim 3, wherein the emission surface includes the convex surface, and a half-value angle of emitted light is 135 ° or more in the X-axis direction and 165 ° or more in the Y-axis direction. The X axis is in the direction of the long axis of the blue LED device, the Y axis is an axis orthogonal to the X axis,
4. The pseudo white LED device according to claim 3, wherein the emission surface includes a plane, and a half-value angle of the emitted light is 145 ° or more in the X-axis direction and 185 ° or more in the Y-axis direction. The X axis is in the direction of the major axis of the blue LED device, the Y axis is an axis orthogonal to the X axis, and further includes the X axis and a Z axis perpendicular to the Y axis,
7. The pseudo white LED device according to claim 3, wherein the silicone cap has a flat surface facing the light emitting surface, and a central thickness on the Z-axis of 0.7 to 1.5 mm. .   The pseudo white LED device according to any one of claims 1 to 7, comprising 2 to 20 parts by mass of a light diffusing material with respect to 100 parts by mass of the silicone polymer. A light emitting surface of a blue LED device comprising a blue LED element, a package member including a concave portion that accommodates the blue LED element, and a transparent resin sealing material that seals the LED element accommodated in the concave portion to form a light emitting surface. A silicone cap including at least a YAG-based phosphor, a light diffusing material, and a silicone polymer,
Including an exit surface that transmits and emits light emitted from the light emitting surface;
The silicone cap, wherein the exit surface includes a three-dimensional curved surface formed by a plane, a convex surface, a concave surface, or a combination thereof.