Semiconductor light-emitting device
View Patent ↗A semiconductor light-emitting device includes a semiconductor light-emitting thin film, the thickness h of which satisfies the following conditional equation: 0.9 × ( 2 m + 1 ) λ 0 4 n ≦ h ≦ 1.1 × ( 2 m + 1 ) λ 0 4 n and m in the conditional equation satisfies the following conditional equation: 2 m + 1 m ( m + 1 ) λ 0 2 > ξ where λ 0 is a center wavelength of light generated in the semiconductor light-emitting thin film, n is a refractive index of the semiconductor light-emitting thin film, m is 0 or a positive integer, and ξ is a half bandwidth of a light emission spectrum when there is no interference between light rays generated in the semiconductor light-emitting thin film.
1. A semiconductor light-emitting device comprising:
a semiconductor light-emitting thin film having a first surface and a second surface arranged facing in opposite directions;
a first optically reflecting surface disposed on said first surface of said semiconductor light-emitting thin film; and
a second optically reflecting surface disposed on said second surface of said semiconductor light-emitting thin film,
wherein light generated in said semiconductor light-emitting thin film passes through said first surface and is then emitted,
wherein when λ 0 is a center wavelength of light generated in said semiconductor light-emitting thin film, n is a refractive index of said semiconductor light-emitting thin film, h is a thickness of said semiconductor light-emitting thin film, m is 0 or a positive integer, and ξ is a half bandwidth of a light emission spectrum when there is no interference between light rays generated in said semiconductor light-emitting thin film, the thickness h satisfies a following first conditional equation:
0.9
×
(
2
m
+
1
)
λ
0
4
n
≦
h
≦
1.1
×
(
2
m
+
1
)
λ
0
4
n
and, when m is not 0, m in the first conditional equation satisfies a following second conditional equation:
2
m
+
1
m
(
m
+
1
)
λ
0
2
>
ξ
.
2. The semiconductor light-emitting device according to claim 1 , wherein said second optically reflecting surface is a surface of a metal layer disposed on a side of the second surface of said semiconductor light-emitting thin film.
3. The semiconductor light-emitting device according to claim 1 , wherein said first optically reflecting surface is a surface of an electrode disposed on a side of the first surface of said semiconductor light-emitting thin film.
4. The semiconductor light-emitting device according to claim 1 , wherein said semiconductor light-emitting thin film is an epitaxial film.
5. An LED head comprising the semiconductor light-emitting device according to claim 1 .
6. An image-forming apparatus comprising the LED head according to claim 5 .
7. A semiconductor light-emitting device comprising:
a semiconductor light-emitting thin film having a first surface and a second surface arranged facing in opposite directions;
a first optically reflecting surface disposed on said first surface of said semiconductor light-emitting thin film; and
a second optically reflecting surface disposed on said second surface of said semiconductor light-emitting thin film,
wherein light generated in said semiconductor light-emitting thin film passes through said first surface and is then emitted,
wherein when λ 0 is a center wavelength of light generated in said semiconductor light-emitting thin film, n is a refractive index of said semiconductor light-emitting thin film, h is a thickness of said semiconductor light-emitting thin film, m is 0 or a positive integer, and ξ is a half bandwidth of a light emission spectrum when there is no interference between light rays generated in said semiconductor light-emitting thin film, the thickness h substantially satisfies a following first conditional equation:
h
=
(
2
m
+
1
)
λ
0
4
n
and, when m is not 0, m in the first conditional equation satisfies a following second conditional equation:
2
m
+
1
m
(
m
+
1
)
λ
0
2
>
ξ
.
8. The semiconductor light-emitting device according to claim 7 , wherein said second optically reflecting surface is a surface of a metal layer disposed on a side of the second surface of said semiconductor light-emitting thin film.
9. The semiconductor light-emitting device according to claim 7 , wherein said first optically reflecting surface is a surface of an electrode disposed on a side of the first surface of said semiconductor light-emitting thin film.
10. The semiconductor light-emitting device according to claim 7 , wherein said semiconductor light-emitting thin film is an epitaxial film.
11. An LED head comprising the semiconductor light-emitting device according to claim 7 .
12. An image-forming apparatus comprising the LED head according to claim 11 .
13. A semiconductor light-emitting diode, comprising:
an LED thin film having a first surface and a second surface arranged facing in opposite directions;
a first optically reflecting surface disposed on said first surface of said LED thin film; and
a second optically reflecting surface disposed on said second surface of said LED thin film,
wherein light generated in said LED thin film passes through said first surface and is then emitted,
wherein when λ 0 is a center wavelength of light generated in said LED thin film, n is a refractive index of said LED thin film, h is a thickness of said LED thin film, m is 0 or a positive integer, and ξ is a half bandwidth of a light emission spectrum when there is no interference between light rays generated in said LED thin film, the thickness h satisfies a following first conditional equation:
0.9
×
(
2
m
+
1
)
λ
0
4
n
≦
h
≦
1.1
×
(
2
m
+
1
)
λ
0
4
n
and, when m is not 0, m in the first conditional equation satisfies a following second conditional equation:
2
m
+
1
m
(
m
+
1
)
λ
0
2
>
ξ
.
14. The semiconductor light-emitting diode according to claim 13 , wherein said second optically reflecting surface is a surface of a metal layer disposed on the second surface of said LED thin film.
15. The semiconductor light-emitting diode according to claim 13 , wherein said first optically reflecting surface is a surface of an electrode disposed on the first surface of said LED thin film.
16. The semiconductor light-emitting device according to claim 13 , wherein said LED thin film is an epitaxial film.
17. The semiconductor light-emitting device according to claim 13 , wherein the thickness h of said LED thin film is about 2067 nm or less.