KR20080024996A - Red emission phosphor and white emission device with the same - Google Patents

Abstract

A red light emitting phosphor is provided to accomplish efficient emission of red light in the presence of an excitation light source having a wavelength of 370-410 nm and 455-470 nm, and to fabricate a white light emitting device capable of light emission with a high luminance. A red light emitting phosphor emits a red phosphorescence in the presence of an excitation light source and is represented by the formula of Sr(La1-xEux)6W10O40, wherein x is greater than 0 and equal to or less than 1. A white light emitting device has a UV light emitting device having a UV light emission peak at 370-410 nm, the red light emitting phosphor, a green light emitting phosphor and a blue light emitting phosphor.

Description

RED EMISSION PHOSPHOR AND WHITE EMISSION DEVICE WITH THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a red light emitting phosphor that efficiently emits red fluorescence by blue excitation light from ultraviolet rays and a white light emitting element using the same.

In recent years, with the development of a blue light emitting element, the development of a white light emitting element is progressing. The white light emitting element is a combination of a blue light emitting element and a yellow light emitting phosphor that receives blue light emitted from the blue light emitting element and emits yellow, which is a blue complementary color.

JP-A-10-093146, JP-A-10-065221, JP-A-10-242513 and the like include a sealing resin surrounding a blue light emitting diode (blue LED) using a nitride semiconductor. Phosphor doped with Ce in a YAG-based oxide matrix lattice known as a composition formula of (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ that receives blue light as excitation light and emits yellow fluorescence (YAG: Ce phosphor) Disclosed is a white light-emitting device in which the dispersion is performed. Japanese Laid-Open Patent Publication No. 11-46015 discloses a white light emitting element in which a non-particulate phosphor layer is formed on a blue LED.

However, since the light composed of blue and its complementary color is poor in color reproducibility and has low color rendering (meaning a tendency to be recognized as white light when a plurality of visible lights are mixed), a white light emitting element called a three wavelength type is developed. have.

A white light emitting device of three wavelengths,

1. A light emitting device that emits blue light, and a white light emitting device that uses a green light emitting phosphor and a red light emitting phosphor that emit blue light by receiving blue light from the light emitting element as excitation light.

2. A light emitting device for emitting ultraviolet light and a white light emitting device using a blue light emitting phosphor, a green light emitting phosphor and a red light emitting phosphor which emit ultraviolet light by receiving the ultraviolet light from the light emitting element as excitation light and the like are known, and the development thereof is in progress. It is becoming.

Japanese Unexamined Patent Publication No. 2000-509912 or the like receives ultraviolet light-emitting diodes and near-ultraviolet rays (370-410 nm) of short wavelengths emitted therefrom, red (590 nm-630 nm), green (520 nm-570 nm), and blue light. Disclosed is a three-wavelength white light emitting device in which phosphors emitting fluorescence of (430 nm to 490 nm) are respectively combined. This white light emitting element arranges an ultraviolet light emitting diode inside a transparent resin formed in a dome shape on a transparent substrate (front panel), and emits three kinds of phosphor powders that emit red, green, or blue light by ultraviolet rays. It has the structure mixed in resin. The surface of transparent resin is mirror-processed so that it may act as a mirror.

In the white LED of the three-wavelength type using an ultraviolet light-emitting diodes, in general, a nitride semiconductor such as InGaN and GaN used as an ultraviolet light-emitting diode, Y ₂ O ₂ S as a red light-emitting phosphor include Eu ^{3 +} is used. The ultraviolet light from the ultraviolet light emitting diode of the nitride semiconductor has an emission peak between 390 nm and 400 nm.

On the other hand, Y ₂ O ₂ S: Eu ^{+ 3,} etc. This is a red light-emitting phosphor, and emits a fluorescent light most efficiently when the wavelength of the light 370㎚, 390㎚ to 400㎚ of the excitation light to the emission intensity of the fluorescent emission of Degrades. For this reason, as a red light-emitting phosphor applied to an ultraviolet light emitting diode that emits ultraviolet light having an emission peak between 390 nm and 400 nm, a red light emitting phosphor that efficiently emits fluorescent light by using an ultraviolet light near 390 nm as excitation light is developed. This is desired.

The reason why the color rendering of light from a light emitting element composed of a blue light emitting element and a phosphor emitting yellow complementary fluorescence is not sufficient is that the fluorescence emitted from the YAG: Ce phosphor is yellow and the luminescence intensity in the red region is Because it is low. A white light emitting diode having improved color rendering property by adding a blue light emitting element and a yellow light emitting phosphor to a red light emitting element that receives blue light from the blue light emitting element and emits red light is disclosed in Japanese Laid-Open Patent Publication No. 2005-179518 and the like. have. Also here, development of the red light-emitting fluorescent substance which receives blue light of the blue light emitting element which emits wavelength blue light of 390 nm-400 nm, and efficiently emits red fluorescence is desired.

Patent Document 1: Japanese Patent Application Laid-Open No. 10-093146

Patent Document 2: Japanese Patent Application Laid-Open No. 10-065221

Patent Document 3: Japanese Patent Application Laid-Open No. 10-242513

Patent Document 4: Japanese Patent Application Laid-Open No. 11-46015

Patent Document 5: Japanese Patent Application Publication No. 2000-509912

Patent Document 6: Japanese Laid-Open Patent Publication 2005-179518

An object of the present invention is to efficiently emit red fluorescence by excitation light having a wavelength of 370 to 410 nm and a wavelength of 455 to 470 nm, and an ultraviolet light emitting diode having an emission peak at 370 to 410 nm, or 455 to 470. It is providing the red luminescent fluorescent substance suitable for the white light emitting element which has a blue light emitting diode which has a light emission peak at nm as a light emitting element. In addition, red fluorescence can be emitted using light in the wavelength region other than the above as excitation light, and the range of combination with the light emitting element and the phosphor in the white light emitting element can be extended, and high luminance light emission can be achieved. It is to provide a red light emitting phosphor.

Moreover, the subject of this invention is providing the white light emitting element which can emit the white light excellent in color rendering efficiency efficiently, and enables light emission of high brightness | luminance.

The present invention relates to a red light-emitting phosphor characterized in that it is represented by the elemental composition formula Sr (La _1-x Eu _x ) ₆ W ₁₀ O ₄₀ (0 <x ≤ 1), which emits red fluorescence upon receiving excitation light. will be.

The present invention also relates to an ultraviolet light emitting element, a red light emitting phosphor emitting red fluorescence by using ultraviolet light emitted by the ultraviolet light emitting element as excitation light, a green light emitting phosphor emitting green fluorescence, and a blue light emitting phosphor emitting blue fluorescence. In a white light emitting device having,

Ultraviolet light emitted from the ultraviolet light emitting element has an emission peak at 370 to 410 nm,

The red light emitting phosphor relates to a white light emitting element characterized in that the red light emitting phosphor represented by the composition formula Sr (La _{1 - x} Eu _x ) ₆ W ₁₀ O ₄₀ (0 <x ≤ 1).

In addition, the present invention provides a white light emitting device comprising a blue light emitting element, a red light emitting phosphor emitting red fluorescence by using blue light emitted by the blue light emitting element as excitation light, and a green light emitting phosphor emitting green fluorescence;

The blue light emitted from the blue light emitting element has an emission peak at 455 to 470 nm,

The red light emitting phosphor relates to a white light emitting element characterized in that the red light emitting phosphor represented by the composition formula Sr (La _{1 - x} Eu _x ) ₆ W ₁₀ O ₄₀ (0 <x ≤ 1).

A white light emitting device comprising a blue light emitting element, a red light emitting phosphor emitting red fluorescence by emitting blue light emitted by the blue light emitting element as excitation light, and a yellow light emitting phosphor emitting yellow fluorescent light,

The blue light emitted from the blue light emitting element has an emission peak at 455 to 470 nm,

The red light emitting phosphor relates to a white light emitting element characterized in that the red light emitting phosphor represented by the composition formula Sr (La _{1 - x} Eu _x ) ₆ W ₁₀ O ₄₀ (0 <x ≤ 1).

The red light-emitting phosphor of the present invention can efficiently emit red fluorescence by excitation light having a wavelength of 370 to 410 nm and a wavelength of 455 to 470 nm, and an ultraviolet light emitting diode having an emission peak at 370 to 410 nm, or 455 to It is preferable for a white light emitting element having a blue light emitting diode having a light emission peak at 470 nm as a light emitting element. In addition, the red light-emitting phosphor of the present invention can emit red fluorescence using green light having a wavelength range of 520 to 550 nm other than the above as excitation light, and in the white light-emitting device, a combination range with a light-emitting element or a phosphor It can be extended and also enables high luminance light emission.

In addition, the white light emitting device of the present invention can efficiently emit white light having excellent color rendering properties, and also enables high luminance light emission.

Implement the invention  Best form for

It characterized in that represented by _{- (x Eu x La 1)} 6 W 10 O 40 (0 <x ≤ 1) red light emitting phosphor of the present invention is a phosphor emitting red fluorescent light receiving excitation light, the composition formula Sr.

In the composition formula Sr (La _{1 - x} Eu _x ) ₆ W ₁₀ O ₄₀ , x represents more than 0 and 1 or less, and preferably 0.2 or more and 1 or less. Specifically, the red light-emitting phosphor includes strontium (Sr), europium (Eu), tungsten (W), and oxygen (O), and optionally includes a lantern (La).

The fluorescence emitted by the red luminescent phosphor depends on the concentration of Eu in its luminescence peak intensity, luminance and brightness. In the red light-emitting phosphor, the concentration of Eu can be selected to obtain desired light emission intensity, luminance and brightness. Specifically, if x in the composition formula is in the range of 0.2 ≦ x ≦ 1.0, the brightness is high, and in the range of 0.4 ≦ x ≦ 1.0, fluorescence with high emission peak intensity can be emitted. In particular, the red light-emitting phosphor having a value of x near 0.7 has a very high luminescence peak intensity, a very high Y value in the XYZ color system, high visibility, and emits red fluorescence of high brightness and high brightness.

In addition, when x in the composition formula is in a range of 0.6 ≦ x ≦ 0.9, the emission peak intensity of the fluorescence from the red luminescent phosphor and the Y value of the three stimulus values in the XYZ colorimeter are hardly changed, and thus the variation in the manufacturing process and the like. Even if the composition is slightly changed, no change is caused in the characteristics of the red light-emitting phosphor to be manufactured, so that the management in the manufacturing process is easy.

The red light-emitting phosphor is excited with ultraviolet light having a wavelength of 370 to 410 nm as excitation light, and emits red fluorescence. For this reason, red luminescent phosphors are excited by ultraviolet rays from ultraviolet light emitting diodes such as ultraviolet light emitting diodes having a light emission peak near the wavelength of 395 nm near the visible light region and ultraviolet light emitting diodes, and efficiently emit red fluorescence. . In addition, the red light-emitting phosphor is excited efficiently using blue light having a wavelength of 455 to 470 nm as excitation light, and emits red fluorescence. For this reason, it can use suitably as an ultraviolet light emitting element and the red light emitting fluorescent substance for white light emitting elements of the three wavelength type using a blue light emitting element.

The red light-emitting phosphor is excited with green light having a wavelength of 520 to 550 nm as excitation light, and emits red fluorescence. In a white light emitting element of three wavelength type using an ultraviolet light emitting element or a white light emitting element of three wavelength type using a blue light emitting element, green light emission which emits green fluorescence which is excited by a blue light emitting element or an ultraviolet light emitting element, and emits green light In the case of having a phosphor, the red luminescent phosphor is excited by green fluorescence having a wavelength of 520 to 550 nm from the green luminescent phosphor, and emits red fluorescence. For this reason, when used for a white light emitting element, it is possible to increase the red light emission efficiency, to increase the red luminance, and to obtain a white light emitting element having high brightness. Alternatively, the amount of red luminescent phosphors used may be reduced to obtain red fluorescence of equivalent luminance.

The excitation light spectrum (peak wavelength and excitation wavelength of the excitation light) in the red light emitting phosphor has little dependence on the Eu concentration, and it is assumed that the involvement of Eu is low in the excitation of the red light emitting phosphor.

[Method for producing red light-emitting phosphor]

The manufacturing method of the red luminescent phosphor of this invention is demonstrated.

Raw materials include strontium compounds such as strontium carbonate (SrCO ₃ ), lantern compounds such as lantern oxide (La ₂ O ₃ ), europium compounds such as europium oxide (Eu ₂ O ₃ ), and tungsten compounds such as tungsten oxide (WO ₃ ) Use Each of these raw materials is weighed, collected according to the composition formula, and thoroughly mixed wet or dry.

The mixture is filled into heat-resistant containers such as alumina crucibles and platinum crucibles, and calcined at 900 to 1100 ° C. for 3 to 10 hours in the air, and the resulting fired material is pulverized, washed, dried, and classified to obtain a red light-emitting phosphor.

In addition, preliminary baking may be performed at 500-800 degreeC for 3 to 6 hours before baking, and the phosphor powder obtained by baking may be refired. Preliminary baking, baking, and refiring are preferably performed in an oxidizing atmosphere.

[White light emitting element]

The white light emitting device of the present invention is an ultraviolet light emitting device having an emission peak at 370 to 410 nm, and a green light emitting phosphor, a blue light emitting phosphor, and the red light emitting phosphor that emit fluorescence using the ultraviolet light emitted by the ultraviolet light emitting element as excitation light. Has

Examples of the ultraviolet light emitting device include ultraviolet light emitting diodes, laser diodes, and the like, which emit ultraviolet light having an emission peak at 370 to 410 nm. The green light-emitting fluorescent substance as by ultraviolet light of 370 ~ 410㎚ with excitation light, and preferably for emitting green fluorescent light having a wavelength of 520 ~ 550㎚, for example, ZnS: Cu, Al, BaMgAl 10 O 17: Eu 2 + ^{, Mn 2 +, (Ba,} Sr) 2 SiO 4: Eu ^{2 +} may be exemplified such ^{as: Eu 2 +, (Sr,} Ca, Ba) Ga 2 S 4: Eu 2 +, β- siAlON. Examples of the blue light emitting phosphor include Sr ₅ (PO ₄ ) ₃ Cl: Eu, ZnS: Ag, BaMgAl ₁₀ O ₁₇ : Eu, and the like, which emit blue fluorescent light having a wavelength of 455 to 470 nm by using ultraviolet rays of 370 to 410 nm as excitation light. Can be illustrated.

In this white light emitting element, the red light emitting phosphor is excited by fluorescence emitted from the green light emitting phosphor and the blue light emitting phosphor in addition to the ultraviolet light from the ultraviolet light emitting element, and emits red fluorescence. The red fluorescence and the green light emitting phosphor When the fluorescence from a blue light emitting fluorescent material is mixed, white light with high color rendering and high brightness can be obtained.

Further, another white light emitting device of the present invention includes a blue light emitting device having an emission peak at 455 to 470 nm, a green light emitting phosphor that emits fluorescence using blue light emitted by the blue light emitting device as excitation light, and the red light emission Has a phosphor.

As said blue light emitting element, a blue light emitting diode, a laser diode, etc. which have an emission peak in 455-470 nm can be illustrated. As the green light emitting phosphor, it is preferable to emit green fluorescence having a wavelength of 520 to 550 nm by using blue light having a wavelength of 455 to 470 nm as excitation light. For example, SrGa ₂ S ₄ : EU, (Ba, Sr) ₂ SiO _4: Ce, etc. can be ^{exemplified: Eu 2 +, (Sr,} Ca, Ba) Ga 2 S 4: Eu 2 +, β- _{^{siAlON: Eu 2 +, Ca 3 Sc}} 2 Si 3 O 12.

In this white light emitting element, the red light emitting phosphor is excited by fluorescence emitted from the green light emitting phosphor and emits red fluorescence in addition to the blue light from the blue light emitting element, and the red fluorescence, blue light from the blue light emitting element, and By mixing the green fluorescence from the green luminescent phosphor, the white light having excellent color rendering properties and high brightness and high brightness can be obtained.

In addition, a white light emitting device of another embodiment of the present invention includes a blue light emitting device having an emission peak at 455 to 470 nm, a yellow light emitting phosphor that emits fluorescence using blue light emitted by the blue light emitting device as excitation light, and the red light emitting device Has a phosphor.

Specifically as the blue light emitting device, the same blue light emitting diode as the above example can be specifically illustrated. The yellow-emitting phosphor is preferably in the 455 ~ 470㎚ emit fluorescence at a yellow to a light excitation, and, for _{example, Y 3 Al 5 O 12:} Ce, Ca x Si 12 - (m + n) Al ( _{m + n) O n N 16} -n: Eu 2 + y alpha siAlON phosphor represented by, (Ba, Sr, Ca) 2 SiO 4: Eu 2 +, CaGa 2 S 4: Eu 2 +, (YAG: Ce) system etc. can be illustrated.

This white light emitting element contains a green light emitting phosphor that emits green fluorescence having a wavelength of 520 to 550 nm using the blue light from the blue light emitting element as excitation light, and in addition to the blue light from the blue light emitting element, The red fluorescence phosphor may be excited by the green fluorescence emitted and the emission intensity of the red fluorescence may be increased.

In the white light emitting device, the blue light from the blue light emitting element and the fluorescence from the yellow light emitting phosphor and the red light emitting phosphor are mixed, so that white light having excellent color rendering properties and high brightness and high brightness can be obtained.

Example

[Red light-emitting phosphor]

EXAMPLES 1-10

The _{Sr (La 0 .3 Eu 0 .7} ) 6 W 10 O 40 ( Example 7) was prepared according to the following method.

As a raw material, SrCO ₃ = 1.2735 g, WO ₃ = 20.0000 g, La ₂ O ₃ = 2.5296 g, Eu ₂ O ₃ = 6.3751 g were weighed. The weighed raw material was placed in an alumina mortar and mixed well with an alumina pestle, followed by dry mixing. The mixed powder was charged into an alumina crucible, set in an electric furnace, and calcined at 1000 ° C. for 6 hours in the air. After firing, the fired product obtained by cooling was pulverized and mixed to prepare a target red light-emitting phosphor (Example 7).

SrCO ₃ , WO ₃ , La ₂ O ₃ , and Eu ₂ O ₃ were changed to the amounts used according to the desired composition, and red light emitting phosphors (Examples 1 to 6 and 8 to 10) were prepared in the same manner as above.

The obtained red light-emitting phosphor was filled in a recess (0.8 cm (width) x 1 cm (height) x 0.1 cm (depth)) formed on a flat plate (1 x 2 cm) to prepare a sample, and a light emission spectrum was obtained using this. Three excitation values in an excitation spectrum and an XYZ colorimeter were measured. The XYZ color system is a color system established by the CIE (International Illumination Commission), Y indicates brightness, Z generally indicates the degree of blue, and X indicates other elements. Y can be used as a representative value of brightness.

Comparative Example 1

Commercially available phosphor Y ₂ O ₂ S are of the CRT: a Eu ^{+ 3} was used.

[Measurement of Red Fluorescence]

Using an ultraviolet light emitting diode having an emission peak wavelength of 395 nm as the excitation source, the sample was irradiated with ultraviolet rays from the excitation source, and the emission intensity of 615 nm wavelength light from the samples (Examples 1 to 10) was manufactured by Hamamatsu Photonics. It measured using the PMA-11 type spectrometer. Table 1 and FIG. 1 show the relative intensities obtained by converting the emission intensity of Y ₂ O ₂ S: EU (Comparative Example 1) into 100 from the measured values.

In addition, using the said excitation source, the emission spectrum was measured about the sample (Example 7) using the said spectrometer. A result is shown in FIG. 3 with the result of the comparative example 1. FIG.

[Measurement of Excitation Light]

Using an RF-5300PC-type fluorescence spectrophotometer manufactured by Shimadzu Corporation, the sample (Example 7) was sequentially irradiated with light (excitation light) in the 375 to 550 nm wavelength region to emit light having a 615 nm wavelength emitted from the sample. Intensity was measured. The excitation spectrum is shown in FIG. The excitation spectrum shown in FIG. 2 corresponds to the absorption spectrum of a sample.

From the results, it can be seen that the red light-emitting phosphor of the present invention emits red light by using an ultraviolet region of 370 to 410 nm wavelength, a blue light region of 455 to 470 nm wavelength, and a green light region of 520 to 550 nm wavelength as excitation light. .

[Measurement of 3 stimulation values in XYZ colorimeter]

Using an ultraviolet light emitting diode having an emission peak wavelength of 395 nm as the excitation source, ultraviolet rays from this excitation source were irradiated to the sample (Example 7), and the excitation light was cut using a filter, manufactured by Hamamatsu Photonics Co., Ltd. The Y value of 3 stimulus values in the XYZ colorimeter of the light from a sample was measured using the PMA-11 type spectrometer. Table 1 shows the relative values obtained by converting the Y values of Y ₂ O ₂ S: EU (Comparative Example 1) to 100 from the measured values.

From the above results, the fluorescence which the red light-emitting phosphor of the present invention receives ultraviolet light from the ultraviolet light-emitting element or blue light from the blue light-emitting element emits light, and the emission peak intensity, luminance, and lightness are represented by x in the composition formula. Dependent on, x is 0.2 ≤ x ≤ 1.0, the brightness is higher than that of the comparative example, and x is 0.4 ≤ x ≤ 1.0 in the light emission intensity is greater than the light emission intensity of the comparative example, x is at least 0.2, the phosphor of the comparative example Y ₂ O ₂ S: can be seen that the bright red light than the fluorescence from Eu ^{3 +} obtained. In particular, the fluorescence emitted from the red light-emitting phosphor having a value of x near 0.7 has a light emission peak intensity of 142% of the light emission peak intensity of the comparative example and a Y value of the XYZ colorimeter of about 200% of the Y value of the comparative example. It can be seen that the integrated value is very large compared to the integrated value of the comparative example, the visibility is high, and red light of high brightness and high brightness.

In addition, it can be seen that in the red light-emitting phosphor in the range of 0.6 ≦ x ≦ 0.9, the emission peak intensity and the Y value of the three stimulus values in the XYZ colorimeter are hardly changed.

[White light emitting element]

Example 11

An ultraviolet light emitting diode having a peak of light emission at 395 nm, a red light emitting phosphor of Example 7, Sr ₅ (PO ₄ ) ₃ Cl: Eu as a blue light emitting phosphor, and ZnS: Cu, Al as a green light emitting phosphor A white light emitting diode was prepared.

Example 12

A white light emitting diode was prepared using a blue light emitting diode having an emission band of 465 to 475 nm, a red light emitting phosphor of Example 7 and SrGa ₂ S ₄ : EU as a green light emitting phosphor.

Example 13

A white light emitting diode was prepared by combining Y ₃ Al ₅ O ₁₂ : Ce as a blue light emitting diode having an emission band of 465 to 475 nm, a red light emitting phosphor of Example 7 and a yellow light emitting phosphor that became a blue complementary color.

[Comparative Examples 2 and 3]

As a red emitting phosphor _{Sr (.3 La 0 Eu 0 .7} ) 6 W 10 O Y 2 O 2 S in place of _40: except that the Eu ^{+ 3,} as in Example 11, 12 to prepare a white light emitting diode It was.

[Comparative Example 4]

A white light emitting diode was prepared in the same manner as in Example 13 except that no red light emitting phosphor was used.

When the white light emitting diode of Example 11 is compared with that of Example 11, the white light emitting diode of Example 11 receives the green fluorescence of the green light emitting phosphor and the blue fluorescence of the blue light emitting phosphor in addition to the light emission of the ultraviolet light emitting diode. As a result of emitting red fluorescence, light emission with higher luminance was obtained as compared with the white light emitting diode of Comparative Example 2.

When the white light emitting diode of Example 12 is compared with that of Example 12, the white light emitting diode of Example 12 receives green fluorescence of the green light emitting phosphor in addition to blue light of the blue light emitting diode, and the red light emitting phosphor emits red fluorescence. , Light emission with high luminance was obtained as compared with the white light emitting diode of Comparative Example 3.

Comparing the white light emitting diode of Example 13 with Comparative Example 4, the white light emitting diode of Example 13 obtained white light emission with improved color rendering properties compared to the white light emitting diode of Comparative Example 4.

The red light-emitting phosphor of the present invention can emit red fluorescence by excitation light having a wavelength of 370 to 410 nm, a wavelength of 455 to 470 nm, and a wavelength of 455 to 470 nm, and has an emission peak at 370 to 410 nm. B, it can be preferably used for a white light emitting element having a blue light emitting diode having a light emission peak at 455 to 470 nm as a light emitting element, and the range of combination with a light emitting element and a phosphor in a white light emitting element can be expanded, and also high brightness It is possible to emit light, which is very useful for a white light emitting device.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows the Eu concentration dependency of the emission peak intensity of the red light-emitting phosphor of the present invention.

Fig. 2 is a diagram showing an excitation spectrum of one example (Example 7) of the red light-emitting phosphor of the present invention.

Fig. 3 is a view showing the luminescence peak intensity of one example (Example 7) of the red luminescent phosphor of the present invention.

Claims (8)

Here received light as a phosphor that emits red fluorescence, the composition formula _{Sr (La 1 - x Eu x} ) 6 W 10 O 40 , characterized in that the red light-emitting phosphor represented by (0 <x ≤ 1). The method of claim 1, Wherein x is 0.2 ≦ x ≦ 1. The method of claim 1, Said excitation light is ultraviolet-ray of wavelength 370-410 nm, The red light-emitting phosphor characterized by the above-mentioned. The method of claim 1, The excitation light is blue light having a wavelength of 455 to 470 nm, wherein the red light-emitting phosphor. The method of claim 1, The excitation light is a green light having a wavelength of 520 to 550 nm, wherein the red light-emitting phosphor. To a white light emitting element having an ultraviolet light emitting element, a red light emitting phosphor emitting red fluorescence using an ultraviolet light emitted by the ultraviolet light emitting element as excitation light, a green light emitting phosphor emitting green fluorescence, and a blue light emitting phosphor emitting blue fluorescence; In Ultraviolet light emitted from the ultraviolet light emitting element has an emission peak at 370 to 410 nm, White light emitting device, characterized in that the red light-emitting phosphor represented by _{- (x Eu x La 1)} 6 W 10 O 40 (0 <x ≤ 1) and the red light-emitting fluorescent substance is a composition formula Sr element. In a white light emitting element having a blue light emitting element, a red light emitting phosphor emitting red fluorescence by using blue light emitted by the blue light emitting element as excitation light, and a green light emitting phosphor emitting green fluorescent light, The blue light emitted from the blue light emitting element has an emission peak at 455 to 470 nm, White light emitting device, characterized in that the red light-emitting phosphor represented by _{- (x Eu x La 1)} 6 W 10 O 40 (0 <x ≤ 1) and the red light-emitting fluorescent substance is a composition formula Sr element. In a white light emitting element having a blue light emitting element, a red light emitting phosphor emitting red fluorescence by using blue light emitted by the blue light emitting element as excitation light, and a yellow light emitting phosphor emitting yellow fluorescent light, The blue light emitted from the blue light emitting element has an emission peak at 455 to 470 nm, White light emitting device, characterized in that the red light-emitting phosphor represented by _{- (x Eu x La 1)} 6 W 10 O 40 (0 <x ≤ 1) and the red light-emitting fluorescent substance is a composition formula Sr element.

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