Source: https://patents.google.com/patent/JP4542329B2/en
Timestamp: 2019-12-13 03:26:40
Document Index: 617141808

Matched Legal Cases: ['art 24', 'art 24', 'art 25', 'art 93', 'art 93', 'art 93', 'art 213', 'art 213', 'art 162', 'art 93', 'art 26', 'art 121', 'art 123']

JP4542329B2 - LED lighting source - Google Patents
JP4542329B2
JP4542329B2 JP2003384495A JP2003384495A JP4542329B2 JP 4542329 B2 JP4542329 B2 JP 4542329B2 JP 2003384495 A JP2003384495 A JP 2003384495A JP 2003384495 A JP2003384495 A JP 2003384495A JP 4542329 B2 JP4542329 B2 JP 4542329B2
JP2003384495A
JP2004193581A5 (en
JP2004193581A (en
2003-11-14 Priority to JP2003384495A priority patent/JP4542329B2/en
2004-07-08 Publication of JP2004193581A publication Critical patent/JP2004193581A/en
2004-07-08 Publication of JP2004193581A5 publication Critical patent/JP2004193581A5/ja
2010-09-15 Publication of JP4542329B2 publication Critical patent/JP4542329B2/en
The present invention relates to an LED illumination light source including a wavelength changing unit containing a fluorescent material.
In recent years, white LED illumination light sources have been actively studied for the purpose of replacing white light bulbs. As a white LED illumination light source, for example, a blue LED element package using a gallium nitride (GaN) material is coated with a YAG fluorescent material. In the LED illumination light source of this example, light emission with a wavelength of 450 nm is generated from the blue LED element, and the fluorescent material receiving this light emits yellow fluorescence (peak wavelength is about 550 nm). By mixing these lights, white light is provided.
White LED illumination light sources that use LED elements that emit ultraviolet light in combination with fluorescent materials that emit red (R), green (G), and blue (B) light have also been developed. In such an LED illumination light source, the ultraviolet light radiated from the LED element excites the fluorescent material to generate red, blue, and green light emission, so that white light can be obtained.
In conventional LED illumination light sources, shell-type packages are widely adopted. Hereinafter, a conventional example of a bullet-type LED illumination light source will be described with reference to FIG.
FIG. 1 shows a cross-sectional configuration example of a conventional LED illumination light source disclosed in Patent Document 1 and the like. The illustrated LED illumination light source 20 includes an LED element 21, a shell-shaped transparent container that covers the LED element 21, and lead frames 22 a and 22 b for supplying current to the LED element 21. The mount portion of the lead frame 22b is provided with a cup-type reflecting plate 23 that reflects the light emitted from the LED element 21 in the direction of arrow D. The inner wall surface (light reflecting surface) of the cup-type reflecting plate 23 is inclined. The LED element 21 is surrounded by the side surface. The LED element 21 mounted on the mount part is sealed with a first resin part 24, and the first resin part 24 is covered with a second resin part 25.
The first resin portion 24 has the LED element 21 mounted in the cup-shaped reflector 23, and after electrically connecting the lead frames 22a and 22b and the cathode electrode and the anode electrode of the LED element 21 via wires, The cup-shaped reflector 23 is filled and cured. The fluorescent material 26 is dispersed inside the first resin portion 24, and the fluorescent material 26 in the first resin portion 24 is excited by the light A emitted from the LED element 21. From the excited fluorescent substance 26, fluorescence (light B) having a wavelength longer than the wavelength of the light A is generated. When the light A emitted from the LED element 21 is red, the light B emitted from the fluorescent material 26 is configured to be yellow light. A part of the light A is transmitted through the first resin portion 24 containing the fluorescent material 26, so that the light C in which the light A and the light B are mixed is used as illumination light. For example, the light A shows a narrow band spectral distribution with a peak wavelength of about 470 nm, and the light B shows a broadband spectral distribution with a peak wavelength of about 570 nm.
Japanese Patent No. 2998696
The conventional LED illumination light source shown in FIG. 1 has a problem of poor color rendering. FIG. 2 shows an example of the spectral distribution of the white LED illumination light source having the configuration shown in FIG. As can be seen from FIG. 2, according to such a white LED illumination light source, the amount of light emission in the red wavelength range is smaller than the amount of light emission in the other wavelength ranges, thereby deteriorating the color rendering.
“Color rendering” is the property of a light source that determines how the color of an object illuminated by illumination light appears. The color rendering properties of the light source can be evaluated by an average color rendering index (Ra). The higher the value Ra, the better the color rendering.
According to the international standard ISO 8895-1989, light sources having an average color rendering index Ra of 90 or more are classified into Group 1A, and light sources having an average color rendering index Ra of 80 or more and less than 90 are classified into Group 1B. The preferred magnitude of the average color rendering index Ra varies depending on the use of the light source, but is generally desirably 70 or more.
However, with a conventional white LED illumination light source using a blue LED element, it has been difficult to achieve an average color rendering index Ra of 70 or more depending on the light color.
This invention is made | formed in view of the said subject, The place made into the objective is to provide the LED illumination light source which improved the color rendering property.
An LED illumination light source according to the present invention includes at least one LED element and a wavelength conversion unit containing a fluorescent material that converts light emitted from the LED element into light having a wavelength longer than the wavelength of the light. The LED illumination light source is adjusted such that the spectral transmittance in at least a part of the wavelength range selected from the wavelength range of 550 nm to 605 nm is lower than the spectral transmittance in other visible light wavelength ranges. Filter means is further provided.
In a preferred embodiment, the LED element emits light having a peak wavelength in a range of 400 nm or more and 490 nm or less.
In a preferred embodiment, the LED element is mounted on a substrate.
In a preferred embodiment, the LED element is mounted on the substrate in a flip chip state.
In a preferred embodiment, the wavelength conversion unit is made of a resin.
In a preferred embodiment, the wavelength conversion unit has a cylindrical shape and covers the entire LED element.
In preferable embodiment, resin is formed so that the said wavelength conversion part may be covered.
In a preferred embodiment, the filter means is disposed so as to cover the wavelength converter.
In a preferred embodiment, the filter means is made of resin.
In a preferred embodiment, each of the wavelength conversion unit and the filter unit is made of resin, and there is no substantial interface between the wavelength conversion unit and the filter unit.
In a preferred embodiment, the wavelength conversion section formed from a resin contains an Nd compound, and the wavelength conversion section also functions as the filter means.
In preferable embodiment, it has the reflecting plate which has the opening part surrounding the said wavelength conversion part.
In a preferred embodiment, the filter means is adjusted so that the spectral transmittance in the wavelength range of 575 nm to 590 nm is lower than the spectral transmittance in other visible light wavelength ranges.
In a preferred embodiment, the spectral transmittance of the filter means in the wavelength range of 575 nm to 590 nm is adjusted to a range of 10% to 95% of the spectral transmittance in another visible light wavelength range.
In a preferred embodiment, the spectral transmittance of the filter means is adjusted to increase the average color rendering index Ra.
In preferable embodiment, it has the card | curd shape which can be attached or detached with respect to the illuminating device provided with the lighting circuit.
ADVANTAGE OF THE INVENTION According to this invention, the average color rendering evaluation number Ra of an LED illumination light source can be improved by applying the filter member which selectively reduced the spectral transmittance of a specific wavelength range to an LED illumination light source.
In order to find a spectral distribution useful for improving the average color rendering index Ra of the LED illumination light source, the present inventor performed a simulation described below.
First, as a premise of the simulation, the light emitted from the LED element has a narrow-band spectral distribution with a peak wavelength of 460 nm, and the light emitted from the fluorescent material has a broadband spectral distribution with a peak wavelength of 575 nm. The spectral distribution of the LED illumination light source is adjusted so that the color temperature of the illumination light formed by mixing the light emitted from the LED element and the light emitted from the fluorescent material (fluorescence) is 4000K. The spectral distribution of the illumination light was actually measured. The actual measurement was performed by changing the measurement wavelength by 5 nm in a band from 380 nm to 780 nm (visible light wavelength band). As a result, 81 data points were obtained, and the average color rendering index Ra was 70.
Next, using the above spectral distribution data, how the average color rendering index Ra changes when the spectral transmittance in a narrow band having a width of 5 nm is set to 0% was obtained by calculation. That is, the average color rendering evaluation when one measurement band (bandwidth: 5 nm) is selected from the above-described spectral distribution data (81) obtained by actual measurement and the spectral transmittance in the selected wavelength range is 0%. The number Ra is calculated. This operation was sequentially performed over the entire visible light wavelength band from 380 nm to 780 nm.
FIG. 3 is a graph showing the above calculation results. The horizontal axis of the graph indicates the center value of the narrow wavelength band (width 5 nm) where the spectral transmittance is 0%, and the vertical axis indicates the increase or decrease of the average color rendering index Ra. The increase / decrease in the average color rendering index Ra was evaluated based on the average color rendering index Ra related to the illumination light obtained without passing the filter from the LED illumination light source.
In the graph of FIG. 3, a calculation result having a peak at a wavelength of 570 nm is shown. Here, the data point at the wavelength λnm is the average color rendering index Ra of the illumination light obtained when the spectral transmittance in the band of the wavelength (λ−2.5) nm to (λ + 2.5) nm is 0%. The amount of change.
As can be seen from the graph of FIG. 3, the spectral transmittance in the wavelength range where the spectral transmittance is not intentionally reduced (for example, the spectral transmittance having a wavelength of 510 nm) is selected from the range of wavelengths from 550 nm to 605 nm. The average color rendering index Ra of the LED illumination light source is improved by reducing the spectral transmittance in the arbitrary wavelength range. In particular, the average color rendering index Ra can be effectively improved by reducing the spectral transmittance in the wavelength band from 575 nm to 590 nm. Such control of spectral transmittance can be realized by using a filter member having appropriate transmission characteristics. In JP-A-5-290818, in a glass tube light bulb used for interior lighting of a refrigerator or the like, yellow light (wavelength 570 to 590 nm) is absorbed by adding neodymium oxide into the glass tube. Technology is disclosed. According to this technique, it is possible to show the colors of the items in the warehouse vividly, but the average color rendering index Ra decreases.
Next, the relationship between the transmission characteristics of the filter member, the average color rendering index Ra of the LED illumination light source, and the luminous flux will be described.
[Filter member F1]
First, refer to FIGS. 4A and 4B. 4A shows the spectral transmittance of the filter member F1, and FIG. 4B shows the spectral distribution of light emitted from the LED illumination light source provided with the filter member F1.
As can be seen from FIG. 4A, in the filter member F1, the spectral transmittance in the wavelength range from 510 nm to 605 nm is lower than the spectral transmittance in other wavelength ranges (for example, wavelength 510 nm).
The average color rendering index Ra of the LED illumination light source provided with such a filter member F1 was 68. On the other hand, when the filter member F1 is not used, in other words, when a transparent member having a spectral transmittance of 100% in the visible light wavelength range is used instead of the filter member F1, the average color rendering index Ra is 65. It was. That is, the average color rendering index Ra was increased by 3 by using the filter member F1. Moreover, by using such a filter member F1, the luminous flux of the LED illumination light source is reduced to 72% of the luminous flux when the filter member F1 is not used.
Thus, the average color rendering index Ra of the LED illumination light source is improved by using the filter member in which the spectral transmittance of the wavelength of 510 nm to 605 nm or less is decreased with respect to the spectral transmittance of the wavelength of 510 nm.
As described above, it can be seen from the graph of FIG. 3 that the average color rendering index Ra of the LED illumination light source is particularly improved by selectively reducing the spectral transmittance in the wavelength range of 550 nm to 605 nm. The transmittance characteristics shown in FIG. 4 (a) lower the spectral transmittance in a wider range including the range of 550 nm to 605 nm, that is, in the range of more than 510 nm to 605 nm or less than in other visible light wavelength ranges. ing. In this case, the decrease in the spectral transmittance in the wavelength range from 510 nm to less than 550 nm does not particularly contribute to the improvement of the average color rendering index Ra, but the average color rendering evaluation is caused by the decrease in the spectral transmittance in the wavelength range of 550 nm to 605 nm. The number Ra is considered to be improved.
If the wavelength range for reducing the spectral transmittance is extended more than necessary, the luminous flux decreases, which is not preferable. In particular, since light having a wavelength of about 550 nm belongs to the green wavelength range where human visibility is high, the spectral transmittance in the range of 550 nm to 605 nm is selectively reduced while maintaining the spectral transmittance at a wavelength of 550 nm high. It is preferable to make it. The wavelength range in which the spectral transmittance should be reduced is preferably selected from the range of 550 nm to 605 nm, but the spectral transmittance outside this wavelength range may be reduced.
In the above example, a blue LED having an emission peak wavelength of about 460 nm is used as the LED element, but the effect of the present invention is when an LED element having an emission peak wavelength in the range of 400 nm to 490 nm is used. It is remarkable.
[Filter member F2]
Next, refer to FIGS. 5A and 5B. FIG. 5A shows the spectral transmittance of the filter member F2, and FIG. 5B shows the spectral distribution of light emitted from the LED illumination light source including the filter member F2.
As shown in FIG. 5A, in the filter member F2, the spectral transmittance at a wavelength of 560 nm to 605 nm is decreased with respect to the spectral transmittance at a wavelength of 510 nm. By using such a filter member F2, the average color rendering index Ra increased to 72 and the luminous flux decreased to 90%.
In this way, by using the filter member in which the spectral transmittance of the wavelength 550 nm to 605 nm is decreased with respect to the spectral transmittance of the wavelength 510 nm, the average color rendering index Ra of the LED illumination light source is set while suppressing the decrease in the luminous flux. It can be improved efficiently.
[Filter member F3]
Next, refer to FIGS. 6 (a) and 6 (b). FIG. 6A shows the spectral transmittance of the filter member F3, and FIG. 6B shows the spectral distribution of light emitted from the LED illumination light source provided with the filter member F3.
As can be seen from FIG. 6A, the filter member F3 has a spectral transmittance in the wavelength range of 575 nm to 590 nm that is 95% of the spectral transmittance in the other wavelength range (for example, wavelength 510 nm). Yes. By using this filter member F3, the average color rendering index Ra slightly increased to 66. The luminous flux was 99% of the luminous flux when the filter member F3 was not used.
Thus, even when a filter member in which the spectral transmittance in the range of 575 nm to 590 nm is reduced by only 5% with respect to the spectral transmittance of 510 nm, the average color rendering index Ra can be improved.
[Filter member F4]
Next, FIG. 7A and FIG. 7B will be referred to. FIG. 7A shows the spectral transmittance of the filter member F4, and FIG. 7B shows the spectral distribution of light emitted from the LED illumination light source provided with the filter member F4.
As can be seen from FIG. 7A, the filter member F4 has a spectral transmittance in the wavelength range of 575 nm or more and 590 nm or less that is only 10% of the spectral transmittance in another wavelength range (for example, wavelength 510 nm). Absent. By using this filter member F4, the average color rendering index Ra was greatly increased to 82. On the other hand, the luminous flux was 80% of the luminous flux when no filter member was used. The decrease in the luminous flux of the LED illumination light source accompanying the improvement in the average color rendering index Ra is reasonable at 80% from the viewpoint of practicality. For this reason, it is not preferable that the luminous flux be smaller than this.
As described above, when a filter member in which the spectral transmittance in the wavelength range of 575 nm or more and 590 nm or less is greatly reduced to 10% of the spectral transmittance in other wavelength ranges (for example, 510 nm), the average color rendering index Ra is greatly increased. Can be improved. However, if the spectral transmittance in the wavelength range of 575 nm or more and 590 nm or less is further reduced, the reduction of the luminous flux exceeds the allowable range, which is not preferable.
[Filter member F5]
Next, refer to FIGS. 8A and 8B. FIG. 8A shows the spectral transmittance of the filter member F5, and FIG. 8B shows the spectral distribution of light emitted from the LED illumination light source provided with the filter member F5.
As can be seen from FIG. 8A, the filter member F5 has a spectral transmittance in the wavelength range of 575 nm to 590 nm that is 50% of the spectral transmittance in the other wavelength range (for example, wavelength 510 nm). Yes.
By using the filter member F5, the average color rendering index Ra of the LED illumination light source increases to 74. Further, the luminous flux of the present embodiment is 90% of the luminous flux when no filter member is used. Thus, if the decrease in the luminous flux of the LED illumination light source accompanying the improvement in the average color rendering index Ra is within 10%, there is no problem in terms of practicality.
As can be seen from the above, the spectral transmittance in at least a part of the wavelength range selected from the wavelength range of 510 nm or more and 605 nm or less is adjusted to be lower than the spectral transmittance in other visible light wavelength ranges. The average color rendering index Ra can be improved by filtering the light emitted from the LED illumination light source using the filter member.
In addition, it is efficient that the wavelength range for selectively reducing the spectral transmittance as compared with other wavelength ranges is 550 nm or more and 590 nm or less. By using a filter member having a spectral transmittance in this wavelength range of 10 to 95% of the spectral transmittance in other wavelength ranges, the average color rendering index Ra is improved while maintaining the luminous flux at a required level. Can be made. The spectral transmittance in the wavelength range of 550 nm to 590 nm is preferably adjusted to 50% to 95% and more preferably 70% to 95% of the spectral transmittance in the other wavelength range. . The spectral transmittance at a wavelength of 550 nm is preferably maintained at 90% or more compared to the spectral transmittance in a band where the spectral transmittance is not reduced.
Hereinafter, an LED illumination light source according to the present invention will be described with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of simplicity.
First, a first embodiment of the LED illumination light source of the present invention will be described with reference to FIG.
The LED illumination light source shown in FIG. 9A includes a substrate 91, an LED element 92 mounted on the substrate 91, a resin portion 93 containing a fluorescent material (phosphor), and a filter member 94.
In the present embodiment, the LED element 92 is mounted on the main surface of the substrate 91 in a flip chip state. A wiring (not shown) is formed on the substrate 91 and is electrically connected to an electrode on the mounted LED element 92. On the LED element 92, a current or voltage necessary for light emission is supplied from a lighting circuit (not shown) via the wiring of the substrate 91.
The fluorescent material dispersed inside the resin portion 93 is absorbed by the light emitted from the LED element 92 and excited, and then emits fluorescence. The wavelength of the light emitted from the fluorescent material is longer than the wavelength of the light emitted from the LED element 92. For example, when an LED chip that emits blue is used as the LED element 92, the fluorescent material is (Y · Sm) 3 (Al · Ga) 5 O 12 : Ce, (Y 0.39 Gd 0.57 Ce 0.03 Sm 0.01 ) 3 Al 5 O 12 or the like can be preferably used. By using such a fluorescent material, part of the blue light emitted from the LED element 92 can be converted into yellow light, and illumination light close to white as a whole can be obtained.
The resin portion 93 in the present embodiment has a side surface separated from a surface (not shown) that can reflect light emitted from the resin portion 93. Specifically, the resin portion 93 has a cylindrical shape having a diameter longer than the diagonal length of the LED element 92 and a height larger than the height of the LED element 92, and the side surface of the resin portion 93 is the LED element 92. It is comprised from the curved surface surrounding the side part. Here, the “surface that can reflect the light emitted from the resin portion 93” typically includes a light reflecting surface of a light reflecting member that is intentionally arranged for reflection, but other members' It may be the surface.
For example, the resin portion 93 can be formed as shown in FIG. More specifically, first, a substrate 41 on which the LED element 44 is mounted is prepared. In the present embodiment, the LED element 44 is mounted on the substrate 41 by flip chip mounting. Next, the plate 42 in which the cylindrical hole (opening) is formed is brought into close contact with the substrate 41, and then a resin liquid containing a fluorescent material is poured into the cylindrical hole. The thickness of the plate 42 is, for example, about 0.02 to 1.1 mm, and the diameter of the hole is set to a value (for example, 0.8 mm) larger than the diagonal length (for example, 0.3 to 1.0 mm) of the LED element 44. Is set.
After pouring the resin liquid into the holes of the plate 42, the resin liquid rising above the upper surface of the plate 42 is smoothed by the squeegee 43, and the resin liquid is thermally cured. Thereafter, the plate 42 is removed from the substrate 41 to obtain a columnar resin portion that covers the entire LED element 44.
The filter member 94 according to the present embodiment is disposed outside the resin portion 93 and covers the resin portion 93 so as to receive light emitted from the resin portion 93. The filter member 94 has a characteristic in which the spectral transmittance is lower than the spectral transmittance in other wavelength ranges in at least a part of the band within the wavelength range of 550 nm to 605 nm.
The material of the filter member 94 in this embodiment will not be specifically limited if it has said filtering characteristic. Resins that are relatively inexpensive materials can be suitably used, and among the resins, silicones that are particularly flexible and resistant to heat stress can be suitably used. In order to give the above filtering characteristics to such a resin, for example, an additive such as neodymium, preferably a powder of a neodymium compound such as neodymium oxide, is mixed with the material of the filter member (resin). Can be adjusted. For example, a spectral absorptance of about 10% can be obtained by adding 0.2 weight percent of Nd powder (average particle size 7 μm) to the resin. Instead of using a light-absorbing material, a multilayer interference film deposited on the surface of a transparent member or a chemical coating can be used as the filter member of this embodiment.
FIG. 14 is a graph showing the spectral transmittance characteristics of neodymium oxide. As can be seen from FIG. 14, the spectral transmittance of neodymium oxide is less than 70% of the maximum value in the wavelength range of 550 nm or more and 605 nm or less (spectral absorptance exceeding 30% at the wavelength of 600 nm is shown). ing).
The light emitted from the LED element 92 excites the fluorescent material in the resin portion 93 to generate fluorescence. In FIG. 9, these lights are schematically indicated by an arrow with a reference numeral “95”.
The light 95 has a spectral distribution as shown in FIG. 2, for example, but changes to light having a spectral distribution as shown in FIG. 8B in the process of passing through the filter member 94. As a result, the average color rendering index Ra is improved for the reason described above.
9 illustrates a state in which one LED element 92 is mounted on the substrate 91, but a plurality of LED elements 92 may be mounted on the substrate 91. When a plurality of LED elements 92 are mounted on the substrate 91, each LED element 92 may be covered with a separate filter member 94, or one filter member 94 covers the plurality of LED elements 92. May be. These also apply to other embodiments described below.
The second embodiment of the LED illumination light source of the present invention will be described with reference to FIG. The LED illumination light source of the present embodiment has substantially the same configuration as the LED illumination light source of the first embodiment, but there is a difference in the arrangement relationship between the resin 93 and the filter member 94. In the above-described embodiment, there is a gap between the resin portion 93 and the filter member 94. However, in this embodiment, the resin portion 93 and the filter member 94 are in close contact with each other. If an interface of different substances is formed at the boundary portion 96 between the resin portion 93 and the filter member 94, light is refracted at the interface, so that the light extraction efficiency decreases. In order to maintain high light extraction efficiency, the filter member 94 is preferably formed from the same resin material as the resin portion 93. Further, if the filter member 94 is also made of the same resin before the resin portion 93 is cured in the manufacturing process stage for forming the resin portion 93, the bonding strength between the resin portion 93 and the filter member 94 is increased. This is preferable. In this case, there is substantially no interface between the resin portion 93 and the filter member 94.
A third embodiment of the LED illumination light source of the present invention will be described with reference to FIG. The main difference between the LED illumination light source of the present embodiment and the LED illumination light source of the second embodiment is that a reflecting plate 97 is provided on the substrate 91.
The reflection plate 97 has a reflection surface that reflects light emitted from the side surface portion of the LED element 92 in a direction away from the substrate 91 (preferably in the normal direction of the main surface of the substrate). This reflective surface is formed so as to surround the side surface of the LED element 92. When a plurality of LED elements 92 are mounted on the substrate 91, it is preferable to use a reflecting plate 97 in which openings (through holes) are formed at positions corresponding to the LED elements 92. In this case, the inner wall surface of the opening of the reflecting plate 97 functions as a reflecting surface. The inner wall surface (reflection surface) of the opening provided in the reflection plate 97 is preferably inclined in a tapered shape with respect to the main surface of the substrate. The shape obtained by cutting the reflecting surface by a plane perpendicular to the main surface of the substrate does not have to be linear but may be curved.
The filter member 94 of this embodiment is located in the opening part of the reflecting plate 97, and has a lens function. The filter member 94 of the present embodiment can be suitably formed from a resin as in the above-described embodiment.
A fourth embodiment of the LED illumination light source of the present invention will be described with reference to FIG. The LED illumination light source of the present embodiment is different from the LED illumination light source of the third embodiment in that the resin portion (first resin portion) 93 is covered with the second resin portion 98 and the filter member is provided on the reflection plate 94. 96 is arranged. If an interface exists at the boundary between the first resin portion 93 and the second resin portion 98, the light extraction efficiency is lowered. Therefore, it is preferable that a clear interface is not formed at the boundary.
The filter member 96 of the present embodiment has a flat shape as shown in FIG. 9D, but may have a convex portion that functions as a lens.
In the above first to fourth embodiments, the filter member is provided separately from the resin part 93 containing the fluorescent material, but by adding an additive such as Nd to the resin part 93, at least a part of the resin part 93 is formed. You may make it function as a filter member.
FIG. 15 shows a spectrum of light emitted from the LED illumination light source of the present invention in which neodymium oxide (Nd 2 O 3 ) having the spectral transmittance characteristics shown in FIG. Yes. The amount of neodymium oxide added is 1% by weight, and the amount of phosphor added is 65% by weight. Further, a thixotropic agent (5.5% by weight) having an average particle diameter of 12 nm is added to the resin portion 93 to give a cylindrical shape.
The spectrum of light emitted from the LED illumination light source when no neodymium oxide is added to the resin portion 93 is as shown in FIG. At this time, the peak length of light emitted from the LED element (chip) 92 is 570 nm.
As is apparent from the graph of FIG. 15, a decrease in relative energy intensity was observed at a wavelength of about 600 nm, the average color rendering index Ra was about 94, and an increase of 24 was observed. This is due to light absorption of neodymium oxide contained in the resin portion 93.
Thus, even if the Nd compound is added to the resin portion 93 covering the LED element 92 together with the phosphor, the effect of the present invention can be sufficiently obtained.
The addition of neodymium is preferable because not only the color rendering properties are improved, but neodymium added to the resin also functions as a thixotropic agent and a dispersing agent.
FIG. 11 shows a card-type LED illumination light source according to the present embodiment, a connector 123 into which the LED illumination light source is detachably inserted, and a lighting device 132 that is electrically connected to the LED illumination light source via the connector 123. It is a perspective view shown.
The card-type LED illumination light source 121 shown in the figure is inserted into a connector 123 in which a pair of guide portions 122 are formed. The guide unit 122 has a guide function of sliding the substrate edge of the LED illumination light source 121 in a predetermined direction when the LED illumination light source 121 is inserted into and removed from the connector 123. The connector 123 is provided with a power supply electrode (not shown) that is electrically connected to a power supply electrode (not shown) of the card-type LED illumination light source 121, and is connected to the lighting device 132 via a line 131.
The LED illumination light source 121 preferably includes a plurality of LED elements mounted on a rectangular substrate. Each LED element is covered with the aforementioned cylindrical resin portion, and the resin portion is further covered with a filter member. It has been broken. In this filter member, the spectral transmittance in at least a part of the wavelength range selected from the wavelength range of 550 nm or more and 605 nm or less is lower than the spectral transmittance in other visible light wavelength ranges (for example, the spectral transmittance at a wavelength of 510 nm). It has been adjusted to be.
The board | substrate of the LED illumination light source 121 may have a multilayer wiring which connects each LED element and a power feeding electrode. In addition, a metallic reflector having an opening corresponding to the LED element may be attached to the substrate surface.
Thus, since the LED illumination light source 121 of this embodiment has a card shape similar to a memory card or the like, it can be freely inserted and removed (attached / detached) with respect to various devices having connectors. For this reason, when the life of the LED illumination light source 121 used in the illumination device is exhausted, the illumination device can be continuously used by replacing the LED illumination light source 121 with a new LED illumination light source having the same shape. . Moreover, if necessary ones are appropriately selected from a plurality of types of LED illumination light sources 121 having different characteristics and attached to the illumination device, it is possible to provide various illumination lights while using the same illumination device. .
The configuration of the card-type LED illumination light source 121 of this embodiment will be described in more detail with reference to FIGS. FIG. 12 is an exploded perspective view of the card-type LED illumination light source 121, and FIG. 13 is a cross-sectional view of a region in the card-type LED illumination light source 121 where the LED elements are provided.
First, referring to FIG. The LED illumination light source of this embodiment has a large number of cylindrical resin portions 213 arranged in a matrix on the substrate 11. In FIG. 12, the LED element is not described, but the LED element is molded inside each cylindrical resin portion 213. As described above, the fluorescent material is dispersed in the cylindrical resin portion 213, and the light emitted from the LED element is converted into light having a long wavelength.
On the surface (mounting surface) side of the substrate 11, a light reflecting plate 152 having an opening surrounding each cylindrical resin portion 213 is attached. The inner peripheral surface of the opening of the light reflecting plate 152 functions as a light reflecting surface that reflects light emitted from the cylindrical resin portion 213.
Reference is now made to FIG. Each LED element 153 in this embodiment is connected to the wiring pattern 159 of the multilayer wiring substrate 151 attached to the metal plate 150 constituting the substrate 11 by flip chip mounting. The LED element 153 is covered with a resin part 213 containing a fluorescent substance, and the resin part 213 is covered with a second resin part 162 having a lens function. The second resin portion 162 is doped with neodymium having a concentration of about 0.01 to 30% (preferably 0.1% or more), and is similar to the filter member 94 shown in FIG. 9C. Also works.
In the multilayer wiring board 151 of this embodiment, two layers of wiring patterns 159 are formed, and wiring patterns 159 in different layers are connected by vias 163. The wiring pattern 159 in the uppermost layer is connected to the electrode of the LED element 153 via the Au bump 161. The wiring pattern 159 is constituted by, for example, a wiring pattern formed from copper, nickel, aluminum, or an alloy containing these metals as a main component.
Most of the upper surface of the multilayer wiring board 151 having such a configuration is covered with the light reflecting plate 152, but a part thereof is exposed. In the exposed region on the multilayer wiring board 151, a plurality of power supply electrodes (not shown) are formed. This power supply electrode is electrically connected to the lighting circuit of the lighting device via a connector into which the card type LED illumination light source is inserted.
In the example shown in FIG. 13, an underfill (stress relaxation layer) 160 is provided between the light reflection plate 152 and the multilayer wiring board 151. The underfill 160 relieves stress caused by a difference in thermal expansion between the metal light reflection plate 152 and the multilayer wiring board 151, and the upper layer wiring on the light reflection plate 152 and the multilayer wiring board 51. Electrical insulation between the two is also ensured.
According to this embodiment, illumination light with high color rendering properties can be obtained by a detachable card-type LED illumination light source.
Each of the above embodiments is an LED illumination light source that includes an LED element that emits blue light and a wavelength conversion unit that converts blue light into light having a longer wavelength. The present invention can also be applied to an LED illumination light source including an LED element that emits light and a wavelength conversion unit that converts the ultraviolet light into light having a longer wavelength.
In each of the above embodiments, the filter member is fixed to the substrate on which the LED element is mounted. However, the present invention is not limited to such a configuration. For example, a filter member may be provided in the connector 123 shown in FIG. The important point for the present invention is that the filter member is provided at a position where the illumination light emitted from the LED element and the wavelength conversion unit in the LED illumination light source can be filtered. The present invention can also be suitably applied to a bullet-type LED illumination light source as shown in FIG. In this case, for example, at least a part of the second resin portion 25 or the glass container can function as a filter member.
The present invention is applied to various illumination light sources that replace existing illumination light sources using discharge.
It is sectional drawing which shows the conventional LED illumination light source. It is a graph which shows the spectrum of the light radiated | emitted from an LED element. 6 is a graph showing an average color rendering index Ra when one measurement band (bandwidth: 5 nm) is selected from spectral distribution data (81) and the spectral transmittance in a selected wavelength range is set to 0%. The horizontal axis of the graph indicates the center value of the narrow wavelength band (width 5 nm) where the spectral transmittance is 0%, and the vertical axis indicates the increase or decrease of the average color rendering index Ra. (A) shows the spectral transmittance of the filter member F1 that can be used in the LED illumination light source of the present invention, and (b) is a graph showing the spectral distribution of light emitted from the LED illumination light source provided with the filter member F1. It is. (A) shows the spectral transmittance of the filter member F2 that can be used for the LED illumination light source of the present invention, and (b) is a graph showing the spectral distribution of light emitted from the LED illumination light source provided with the filter member F2. It is. (A) shows the spectral transmittance of the filter member F3 that can be used for the LED illumination light source of the present invention, and (b) is a graph showing the spectral distribution of the light emitted from the LED illumination light source provided with the filter member F3. It is. (A) shows the spectral transmittance of the filter member F4 that can be used in the LED illumination light source of the present invention, and (b) is a graph showing the spectral distribution of light emitted from the LED illumination light source provided with the filter member F4. It is. (A) shows the spectral transmittance of the filter member F5 that can be used in the LED illumination light source of the present invention, and (b) is a graph showing the spectral distribution of light emitted from the LED illumination light source provided with the filter member F5. It is. (A) is sectional drawing which shows 1st Embodiment of the LED illumination light source by this invention, (b) is sectional drawing which shows 2nd Embodiment, (c) is 3rd implementation. It is sectional drawing which shows a form, (d) is sectional drawing which shows 4th Embodiment. It is a perspective view which shows an example of the method of forming the cylindrical resin part (wavelength conversion part) shown in FIG. It is a perspective view which shows 5th Embodiment of the LED illumination light source by this invention. It is a disassembled perspective view of the card type LED illumination light source by this invention. It is sectional drawing of the area | region in which the LED element in the card type LED illumination light source of FIG. 12 is provided. It is a graph which shows the spectral transmittance characteristic of neodymium oxide. It is a graph which shows the spectrum of the light radiated | emitted from the LED illumination light source of this invention which mixed the nebulium oxide which shows the spectral transmittance characteristic shown in FIG. 14 with the resin part 93 with the yellow fluorescent substance.
21 LED element 22a Lead 22b Lead 23 Cup type reflector 24 First resin part (resin part containing fluorescent substance)
25 Second resin part 26 Fluorescent substance 41 Substrate 42 Plate 43 Squeegee 44 LED element 91 Substrate 92 LED element 93 First resin part (resin part containing fluorescent substance)
94 Filter member 95 Radiated light 96 Filter member 97 Reflector plate 98 Second resin part 121 LED illumination light source 122 Guide part 123 Connector 131 Line 132 Lighting device
At least one LED element that emits light having an emission peak wavelength in the range of 400 nm to 490 nm;
A light converter a part of the light emitted from the LED element is converted into yellow light, containing fluorescent substance to obtain white light as a whole,
Filter means further adjusted so that the spectral transmittance in at least a part of the wavelength range selected from the wavelength range of 550 nm to 605 nm is lower than the spectral transmittance in other visible light wavelength ranges. LED illumination light source.
The LED illumination light source according to claim 1, wherein the filter unit is disposed so as to cover the wavelength conversion unit.
The LED illumination light source according to claim 1, wherein the filter means is made of resin.
2. The LED illumination light source according to claim 1, wherein each of the wavelength conversion unit and the filter unit is made of a resin, and no substantial interface exists between the wavelength conversion unit and the filter unit.
The wavelength conversion part formed from a resin contains an Nd compound,
The LED illumination light source according to claim 1, wherein the wavelength conversion unit also functions as the filter unit.
The LED illumination light source according to claim 5, further comprising a reflector having an opening surrounding the wavelength conversion unit.
The filter means according to any one of claims 1 to 6, wherein the filter means is adjusted so that a spectral transmittance in a wavelength range of 575 nm or more and 590 nm or less is lower than a spectral transmittance in another visible light wavelength range. LED illumination light source.
The LED illumination according to claim 7, wherein the spectral transmittance of the filter means in a wavelength range of 575 nm to 590 nm is adjusted to a range of 10% to 95% of a spectral transmittance in another visible light wavelength range. light source.
JP2003384495A 2002-11-25 2003-11-14 LED lighting source Active JP4542329B2 (en)
JP2003384495A JP4542329B2 (en) 2002-11-25 2003-11-14 LED lighting source
JP2004193581A JP2004193581A (en) 2004-07-08
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JP4542329B2 true JP4542329B2 (en) 2010-09-15
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JP2003384495A Active JP4542329B2 (en) 2002-11-25 2003-11-14 LED lighting source
JP (1) JP4542329B2 (en)
JP2007003174A (en) * 2005-05-26 2007-01-11 Matsushita Electric Ind Co Ltd Refrigerator
CN101248533B (en) * 2005-08-23 2010-06-02 株式会社东芝;东芝高新材料公司 Light-emitting device, backlight using same, and liquid crystal display
JP5289126B2 (en) * 2008-03-24 2013-09-11 シチズンホールディングス株式会社 LED light source and chromaticity adjustment method of LED light source
WO2011142127A1 (en) 2010-05-14 2011-11-17 パナソニック株式会社 Led module, led lamp, and illuminating apparatus
JP5974394B2 (en) * 2011-03-23 2016-08-23 パナソニックＩｐマネジメント株式会社 White light emitting device and lighting apparatus using the same
DE102011089144A1 (en) * 2011-12-20 2013-06-20 Osram Gmbh White light spanishing light
JPWO2018055791A1 (en) * 2016-09-21 2019-07-04 積水化成品工業株式会社 Light diffuser for LED lighting cover and use thereof
JP2000011954A (en) * 1998-06-18 2000-01-14 Matsushita Electron Corp Fluorescent lamp and its manufacture
JP2001156336A (en) * 1999-11-30 2001-06-08 Nichia Chem Ind Ltd Light emitting diode
JP2002076446A (en) * 2000-03-27 2002-03-15 General Electric Co <Ge> Single phosphor for creating white light with high luminosity and high cri in uv led device
2003-11-14 JP JP2003384495A patent/JP4542329B2/en active Active
JP2004193581A (en) 2004-07-08
JP2008147190A (en) 2008-06-26 White light emitting device and white light source module using same