Light emitting device and lighting fixture provided with same
To provide a light emitting device that has an excellent color rendering property and a high light emission efficiency, and a lighting fixture provided with the same. A light emitting device including a light emitting element having a light emission peak wavelength in a range of 430 nm or more and 470 nm or less, and a fluorescent member including two or more kinds of rare earth aluminate fluorescent materials including at least one kind selected from the group consisting of a first fluorescent material having a composition represented by the following formula (I) (Y 3 (Al,Ga) 5 O 12 :Ce), a second fluorescent material having a composition represented by the following formula (II) (Lu 3 Al 5 O 12 :Ce), and a third fluorescent material having a composition represented by the following formula (III) (Y 3 Al 5 O 12 :Ce), a fourth fluorescent material having a composition represented by the following formula (IV) (A 2 [M1 1-p Mn 4+ p F 6 ]), and a fifth fluorescent material having a composition represented by the following formula (V) ((Sr,Ca)AlSiN 3 :Eu).
1 . A light emitting device comprising a light emitting element having a light emission peak wavelength in a range of 430 nm or more and 470 nm or less, and
a fluorescent member including fluorescent material consisting of
two or more kinds of rare earth aluminate fluorescent materials including at least one kind selected from the group consisting of a first fluorescent material having a composition represented by the following formula (I), a second fluorescent material having a composition represented by the following formula (II), and a third fluorescent material having a composition represented by the following formula (III),
a fourth fluorescent material having a composition represented by the following formula (IV), and
a fifth fluorescent material having a composition represented by the following formula (V):
Y 3 (Al,Ga) 5 O 12 :Ce (I)
Lu 3 Al 5 O 12 :Ce (II)
Y 3 Al 5 O 12 :Ce (III)
A 2 [M1 1-p Mn 4+ p F 6 ] (IV)
(Sr,Ca)AlSiN 3 :Eu (V)
wherein in the formula (IV), A includes at least one kind selected from the group consisting of K, Li, Na, Rb, Cs, and NH 4 + , M1 includes at least one kind of element selected from the group consisting of a Group 4 element, a Group 13 element, and a Group 14 element, and p represents a number satisfying 0<p<0.2.
2 . The light emitting device according to claim 1 , wherein a content of the fourth fluorescent material with respect to a total content of the rare earth aluminate fluorescent materials is in a range of 0.35 or more and 0.7 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 4,750 K or more and 7,000 K or less.
3 . The light emitting device according to claim 1 , wherein a content of the fourth fluorescent material with respect to a total content of the rare earth aluminate fluorescent materials is in a range of 0.7 or more and 1.3 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 2,500 K or more and 4,750 K or less.
4 . The light emitting device according to claim 1 , wherein a content of the fourth fluorescent material with respect to a total content of the rare earth aluminate fluorescent materials, the fourth fluorescent material, and the fifth fluorescent material is in a range of 0.25 or more and 0.45 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 4,750 K or more and 7,000 K or less.
5 . The light emitting device according to claim 1 , wherein a content of the fourth fluorescent material with respect to a total content of the rare earth aluminate fluorescent materials, the fourth fluorescent material, and the fifth fluorescent material is in a range of 0.4 or more and 0.6 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 2,500 K or more and 4,750 K or less.
6 . The light emitting device according to claim 1 , wherein a total content of the rare earth aluminate fluorescent materials with respect to a total content of the rare earth aluminate fluorescent materials, the fourth fluorescent material, and the fifth fluorescent material is in a range of 0.5 or more and 0.75 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 4,750 K or more and 7,000 K or less.
7 . The light emitting device according to claim 1 , wherein a total content of the rare earth aluminate fluorescent materials with respect to a total content of the rare earth aluminate fluorescent materials, the fourth fluorescent material, and the fifth fluorescent material is in a range of 0.4 or more and 0.6 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 2,500 K or more and 4,750 K or less.
8 . The light emitting device according to claim 1 , wherein a total content of the fourth fluorescent material and the fifth fluorescent material with respect to a total content of the rare earth aluminate fluorescent materials, the fourth fluorescent material, and the fifth fluorescent material is in a range of 0.25 or more and 0.5 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 4,750 K or more and 7,000 K or less.
9 . The light emitting device according to claim 1 , wherein a total content of the fourth fluorescent material and the fifth fluorescent material with respect to a total content of the rare earth aluminate fluorescent materials, the fourth fluorescent material, and the fifth fluorescent material is in a range of 0.4 or more and 0.6 or less, and wherein the light emitting device emits light having a correlated color temperature in a range of 2,500 K or more and 4,750 K or less.
10 . The light emitting device according to claim 1 , wherein the light emitting device has a light emission spectrum having a light emission peak intensity ratio of a light emission peak of the fourth fluorescent material with respect to a light emission peak of the light emitting element in a range of 1.0 or more and 2.0 or less, and emits light having a correlated color temperature in a range of 4,750 K or more and 7,000 K or less.
11 . The light emitting device according to claim 1 , wherein the light emitting device has a light emission spectrum having a light emission peak intensity ratio of a light emission peak of the fourth fluorescent material with respect to a light emission peak of the light emitting element in a range of 2.0 or more and 3.5 or less, and emits light having a correlated color temperature in a range of 3,250 K or more and 4,750 K or less.
12 . The light emitting device according to claim 1 , wherein the light emitting device has a light emission spectrum having a light emission peak intensity ratio of a light emission peak of the fourth fluorescent material with respect to a light emission peak of the light emitting element in a range of 3.5 or more and 5.5 or less, and emits light having a correlated color temperature in a range of 2,850 K or more and 3,250 K or less.
13 . The light emitting device according to claim 1 , wherein the light emitting device has a light emission spectrum having a light emission peak intensity ratio of a light emission peak of the fourth fluorescent material with respect to a light emission peak of the light emitting element in a range of 5.5 or more and 7.0 or less, and emits light having a correlated color temperature in a range of 2,500 K or more and 2,850 K or less.
14 . The light emitting device according to claim 1 , wherein the light emitting element has a light emission peak wavelength in a range of 440 nm or more and 460 nm or less.
15 . The light emitting device according to claim 1 , wherein the first fluorescent material has a light emission peak wavelength in a range of 520 nm or more and 550 nm or less and a full width at half maximum in a range of 95 nm or more and 120 nm or less.
16 . The light emitting device according to claim 1 , wherein the second fluorescent material has a light emission peak wavelength in a range of 500 nm or more and 545 nm or less and a full width at half maximum in a range of 95 nm or more and 105 nm or less.
17 . The light emitting device according to claim 1 , wherein the third fluorescent material has a light emission peak wavelength in a range of 535 nm or more and 555 nm or less and a full width at half maximum in a range of 100 nm or more and 120 nm or less.
18 . The light emitting device according to claim 1 , wherein the fifth fluorescent material has a light emission peak wavelength in a range of 600 nm or more and 630 nm or less and a full width at half maximum of 80 nm or less.
19 . The light emitting device according to claim 1 , wherein the light emitting device has an average color rendering index Ra of 90 or more or a special color rendering index R15 of 85 or more.
20 . A lighting fixture comprising the light emitting device according to claim 1 .
21 . The light emitting device according to claim 1 , wherein the fourth fluorescent material has a full width at half maximum of 10 nm or less.
22 . The light emitting device according to claim 1 , wherein in the formula (IV), A is K, and M1 includes at least one kind of an element selected from the group consisting of silicon and aluminum.