JP2008060129A - Full-color light-emitting diode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and positively adjust a color balance by realizing a full-color LED using the same kinds of LEDs. <P>SOLUTION: The LED has the same kinds of LEDs 3r, 3g, 3b each being mounted on first-third independent mounting spaces 6, 7, 8; an R phosphor excited with a light emitted from the LED 3r, mounted on the first mounting space 6 and emitting a red light; a G phosphor excited with a light emitted from the LED 3g mounted on the second mounting space 7, and emitting a green light; and a B phosphor, excited by a light emitted from the LED 3b mounted on the second mounting space 8, and emitting a blue light. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting diode (LED), and more particularly, to a full color light emitting diode (hereinafter sometimes referred to as “full color LED”) including a plurality of LEDs.

A conventional full color LED is a combination of a plurality of different types of LEDs. Specifically, a red LED emitting R (red) light, a green LED emitting G (green) light, and a blue LED emitting B (blue) light were combined. More specifically, GaN-based single-color LEDs are used for green LEDs and blue LEDs, and quaternary single-color LEDs such as AlInGaP are used for red LEDs (see Patent Document 1).
JP-A-11-003051 ([0005] to [0006])

  In the conventional full color LED, different LEDs are used for each of R, G, and B, and thus there are the following problems. That is, the LED has a characteristic that the peak wavelength changes due to self-heating or the light emission intensity decreases, so it is necessary to adjust the overall color balance by changing the voltage applied to each LED. However, since the types of LEDs used are different, changes in the peak wavelength and light emission intensity of each LED with respect to temperature rise are not uniform, and it is difficult to adjust the color balance. In particular, quaternary single-color LEDs have a large change in peak wavelength and emission intensity, and are difficult to adjust.

  In addition, the color balance may be adjusted by actively changing the voltage applied to each LED. For example, there is a case where a reddish white is obtained by relatively increasing the emission intensity of a red LED. Also in this case, since the types of R, G, and B LEDs are different, it is difficult to adjust the overall color balance, and it is difficult to obtain the intended emission color.

  Furthermore, since the life of each LED is different, even if the overall color balance is adjusted during manufacture, the color balance may be distorted during use.

  The objective of this invention is solving the said subject by implement | achieving full-color LED using the same kind LED.

  The full-color light emitting diode of the present invention that achieves the above object is provided by the same kind of light emitting diodes respectively mounted in at least three independent mounting spaces, and light emitted from the light emitting diodes mounted in the first mounting space. A red phosphor that emits red light when excited, a green phosphor that emits green light when excited by light emitted from a light emitting diode mounted in the second mounting space, and a third phosphor that is mounted in the third mounting space And a blue phosphor that emits blue light when excited by light emitted from the light emitting diode.

  In the full color light emitting diode of the present invention having the above characteristics, the wavelength of light emitted from the light emitting diode is converted by the phosphor. Therefore, desired color light can be obtained simply by changing the type of phosphor, and light of the three primary colors R, G, and B can be obtained using the same light emitting diode.

  The first mounting space, the second mounting space, and the third mounting space are filled with a light transmitting resin, and the light transmitting resin is filled with the red phosphor, the green phosphor, and the blue phosphor. It is preferable to mix.

  Alternatively, the first mounting space, the second mounting space, and the third mounting space are filled with a light transmissive resin, and the light transmissive resin is used as the red phosphor, the green phosphor, or the blue fluorescence. It is preferable to cover with a sheet material mixed with the body.

  As the light emitting diode, a GaN-based light emitting diode having an emission wavelength of 380 nm to 405 nm is preferable.

  In the full color light emitting diode of the present invention, the plurality of light emitting diodes used are all of the same type. Therefore, the change of the peak wavelength and light emission intensity of each light emitting diode with respect to the temperature rise is uniform, and the overall color balance can be easily adjusted. In addition, when the light emission intensity of an arbitrary light emitting diode is relatively increased to obtain color light having a strong arbitrary color, it is easy to adjust the color balance and it is easy to obtain an intended light emission color. Furthermore, since the lifetimes of the respective light emitting diodes are the same, the color balance is less likely to be out of order during use.

(Embodiment 1)
Hereinafter, an example of an embodiment of a full color LED of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic plan view showing the structure of the full color LED 1 of this example. In the full color LED 1 of this example, three LEDs 3r, 3g, and 3b are mounted in a mounting space formed in the package 2.

  In the package 2, the inner side of the concave space opened on the surface 4 of the package 2 is partitioned at 120 ° intervals by the partition walls 5, and the first mounting space 6, the second mounting space 7, and the third mounting space 8 are formed. Is formed. The LED 3r is mounted in the first mounting space 6, the LED 3g is mounted in the second mounting space 7, and the LED 3b is mounted in the third mounting space 8. Here, the three LEDs 3r, 3g, and 3b are all the same LED. Specifically, it is a GaN-based UV-LED (near ultraviolet LED) having an emission wavelength of 380 nm to 405 nm.

  The first to third mounting spaces 6, 7, and 8 in which the LEDs 3r, 3g, and 3b are mounted are filled with a light transmissive resin (transparent resin 9), respectively. Further, different phosphors (not shown) are mixed in the transparent resin 9 filled in the mounting spaces 6, 7, and 8. Specifically, the transparent resin 9 filled in the first mounting space 6 is mixed with a phosphor (hereinafter referred to as “R phosphor”) that is excited by light emitted from the LED 3r and emits red light. Yes. The transparent resin 9 filled in the second mounting space 7 is mixed with a phosphor that emits green light (hereinafter referred to as “G phosphor”) that is excited by light emitted from the LED 3g. In addition, the transparent resin 9 filled in the third mounting space 8 is mixed with a phosphor that is excited by light emitted from the LED 3b and emits blue light (hereinafter referred to as “B phosphor”).

  Further, power supply terminals 10 for supplying power to the LEDs 3r, 3g, and 3b are provided on the opposing side surfaces of the package 2. When a voltage is applied between a predetermined pair of power supply terminals 10, the corresponding LED emits light.

  In the full color LED 1 of this example having the above structure, the light emitted from each LED 3r, 3g, 3b is wavelength-converted by the phosphor mixed in the transparent resin 9 molding the LED 3r, 3g, 3b. R, G, B light. In other words, in the conventional full-color LED, light of the three primary colors of R, G, and B is obtained by combining a plurality of LEDs having different emission wavelengths, but the full-color LED 1 of this example fluoresces the light emitted from the LED. By converting the wavelength by the body, light of the three primary colors of R, G, and B is obtained using the LEDs 3r, 3g, and 3b having the same emission wavelength.

  Therefore, the change in peak wavelength and emission intensity of each LED 3r, 3g, 3b with respect to the temperature rise is uniform, and the adjustment of the overall color balance is easy. In addition, when the applied voltage to any of the LEDs 3r, 3g, and 3b is relatively high to obtain color light having a strong arbitrary color, the color balance can be easily adjusted, and the intended emission color can be obtained. Easy to get. Furthermore, since the lifetimes of the LEDs 3r, 3g, and 3b are the same, the color balance is less likely to be out of order during use.

  Finally, an example of R phosphor, G phosphor, and B phosphor is shown in Table 1. Here, the numerical value described in the rightmost column of Table 1 indicates the peak wavelength (nm) of light emitted when each phosphor is excited by light emitted from the LED 3r, 3g, or 3b. .

(Embodiment 2)
FIG. 2 is a schematic plan view showing another example of the embodiment of the full color LED 20 of the present invention. The basic configuration of the full color LED 20 of this example is the same as the full color LED 1 of the embodiment. Therefore, the configuration common to the first embodiment is described by using the same reference numerals, and only a different configuration is described here.

  A fourth mounting space 22 is formed in the package 21 constituting the full color LED 20 of this example. In the fourth mounting space 22, the same LEDs 23 as the LEDs 3 r, 3 g, and 3 b are mounted, and the same transparent resin 9 as the transparent resin 9 is filled. However, the transparent resin 9 filled in the fourth mounting space 21 is mixed with a phosphor (not shown) that is excited by the light emitted from the LED 23 and emits light of an intermediate color other than R, G, and B. ing.

  In the full color LED 20 of the present example, light of intermediate colors other than R, G, and B can be obtained, so that the color rendering properties are superior to the full color LED 1 of the first embodiment. But the fluorescent substance mixed in the transparent resin 9 with which the 4th mounting space 21 was filled is not limited to the fluorescent substance of the said characteristic. For example, since the R phosphor generally has a low emission intensity, the balance of the emission intensity can be further improved by mixing the R phosphor into the transparent resin 9 filled in the fourth mounting space 21. You can also.

  In the present specification, the embodiment of the present invention has been described by taking as an example the case where a phosphor is mixed into the light-transmitting resin filled in the mounting space. However, the fluorescent material only needs to be able to convert light emitted from the LED into light having a predetermined wavelength, and it is not essential to mix the light into a light-transmitting resin (molding resin). For example, instead of mixing a phosphor into a light transmissive resin, the same effect can be obtained by coating the light transmissive resin with a light transmissive film or a light transmissive sheet mixed with a phosphor. It should be easy to understand.

It is a typical top view which shows an example of embodiment of the full color LED of this invention. It is a typical top view which shows the other example of embodiment of the full color LED of this invention.

Explanation of symbols

1,20 Full color LED
2, 21 package 3r, 3g, 3b, 23 LED
4 Surface 5 Partition 6 First mounting space 7 Second mounting space 8 Third mounting space 9 Transparent resin 10 Power supply terminal 22 Fourth mounting space

Claims (4)

A light emitting diode of the same type each mounted in at least three independent mounting spaces;
A red phosphor that emits red light when excited by light emitted from the light emitting diode mounted in the first mounting space;
A green phosphor that emits green light when excited by light emitted from the light emitting diode mounted in the second mounting space;
A blue phosphor that emits blue light when excited by light emitted from the light emitting diode mounted in the third mounting space;
A full-color light-emitting diode comprising:   The first mounting space, the second mounting space, and the third mounting space each include a light transmissive resin, and the light transmissive resin includes the red phosphor and the green phosphor. The full-color light-emitting diode according to claim 1, wherein the blue phosphor is mixed therein.   A light-transmitting resin filled in each of the first mounting space, the second mounting space, and the third mounting space; and a light-transmitting sheet material that covers the light-transmitting resin. 2. The full color light emitting diode according to claim 1, wherein the red phosphor, the green phosphor or the blue phosphor is mixed in the sheet material.   The full-color light emitting diode according to any one of claims 1 to 3, wherein the light emitting diode is a GaN-based light emitting diode having an emission wavelength of 380 nm to 405 nm.

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