Light-emitting device
A light distribution of light from a light-emitting device ( 10 ) has a higher luminous intensity in a first direction (D 1 ) compared to a reference direction (R), the first direction (D 1 ) being different from the reference direction (R). The reference direction (R) is a center direction of the light distribution, for example, a direction along the thickness direction of a substrate ( 100 ), a direction along the width direction of each layer (for example, an EML ( 126 )) of a resonator ( 150 ), or a normal direction of a second surface ( 104 ) of the substrate ( 100 ). In addition, the light distribution has a higher luminous intensity in a second direction (D 2 ) compared to the reference direction (R), the second direction (D 2 ) being on an opposite side of the first direction (D 1 ) with respect to the reference direction (R).
1. A light-emitting device comprising:
a substrate, wherein the substrate is a single material; and
a light emitting unit, the light emitting unit comprising:
a reflecting layer,
a semi-transparent reflecting layer, and
an organic layer between the reflecting layer and the semi-transparent reflecting layer, the organic layer comprising a light-emitting layer,
wherein the semi-transparent reflecting layer, the organic layer, and the reflecting layer are arranged in this order from the substrate,
wherein the semi-transparent reflecting layer is in contact with the substrate, and
wherein a light distribution of light from the light-emitting unit has a higher luminous intensity in a first direction compared to a reference direction, the reference direction being along a thickness direction of the light-emitting layer from the organic layer to the semi-transparent reflecting layer, and the first direction being different from the reference direction.
2. The light-emitting device according to claim 1 , further comprising k layers from a first layer to a k-th layer (k is an integer that is equal to or greater than 2) between the semi-transparent reflecting layer and the reflecting layer,
wherein a value ΔM defined by Formula (1) below is equal to or greater than in m−⅛ and equal to or less than m+⅛ (m is an integer that is equal to or greater than 1):
[
Formula
1
]
Δ
M
=
2
λ
∑
t
=
1
k
dt
n
t
2
-
n
0
2
sin
2
θ
0
+
1
2
π
(
ϕ
S
+
ϕ
R
)
(
1
)
λ: peak wavelength of light from the light-emitting unit
d i : thickness of i-th layer (1≤i≤k)
n i : refractive index of i-th layer (1≤i≤k)
n 0 : refractive index of medium propagated by light from the light-emitting layer
θ 0 : angle between the reference direction and a direction at which the light distribution has a maximum value
φS: phase shift amount of the semi-transparent reflecting layer
φR: phase shift amount of the reflecting layer.
3. The light-emitting device according to claim 1 ,
wherein the first direction inclines by an angle equal to or greater than 5 degrees and equal to or less than 60 degrees from the reference direction.
4. The light-emitting device according to claim 1 ,
wherein the light distribution has a maximum value in the first direction.
5. The light-emitting device according to claim 1 ,
wherein the light distribution has a higher luminous intensity compared to the reference direction in a second direction on an opposite side of the first direction with respect to the reference direction.
6. The light-emitting device according to claim 1 , further comprising a plurality of the light-emitting units and a plurality of light-transmitting units,
wherein the plurality of light-emitting units comprise a first light-emitting unit and a second light-emitting unit that is adjacent to the first light-emitting unit, and
wherein the plurality of light-transmitting units comprise a first light-transmitting unit between the first light-emitting unit and the second light-emitting unit.
7. A light-emitting device comprising:
a substrate, wherein the substrate is a single material; and
a plurality of light-emitting units, each light-emitting unit comprising:
a reflecting layer,
a semi-transparent reflecting layer, and
an organic layer between the reflecting layer and the semi-transparent layer, the organic layer comprising a light-emitting layer,
wherein the semi-transparent reflecting layer, the organic layer, and the reflecting layer are arranged in this order from the substrate,
wherein the semi-transparent reflecting layer is in contact with the substrate,
wherein a light distribution of light from at least one light-emitting unit out of the plurality of light-emitting units has a higher luminous intensity in a first direction compared to a reference direction, the reference direction being along a thickness direction of the light-emitting layer from the organic layer to the semi-transparent reflecting layer, and the first direction being different from the reference direction, and
wherein the plurality of light-emitting units emit light of different emission colors.
8. The light-emitting device according to claim 7 ,
wherein a light distribution of light from two or more light-emitting units out of the plurality of light-emitting units has the higher luminous intensity in the first direction compared to the reference direction.
9. The light-emitting device according to claim 1 , wherein the substrate is one of a glass substrate and a resin substrate.
10. A light-emitting device comprising:
a substrate; and
a light emitting unit, the light emitting unit comprising:
a reflecting layer,
a semi-transparent reflecting layer, and
an organic layer between the reflecting layer and the semi-transparent reflecting layer, the organic layer comprising a light-emitting layer,
wherein the semi-transparent reflecting layer, the organic layer, and the reflecting layer are arranged in this order from the substrate,
wherein the semi-transparent reflecting layer is in contact with the substrate, and
wherein a light distribution of light from the light-emitting unit has a higher luminous intensity in a first direction compared to a reference direction, the reference direction being along a thickness direction of the light-emitting layer from the organic layer to the semi-transparent reflecting layer, and the first direction being different from the reference direction.
11. A light-emitting device comprising:
a substrate comprising a plane surface; and
a light emitting unit, the light emitting unit comprising:
a reflecting layer,
a semi-transparent reflecting layer, and
an organic layer between the reflecting layer and the semi-transparent reflecting layer, the organic layer comprising a light-emitting layer,
wherein the semi-transparent reflecting layer, the organic layer, and the reflecting layer are arranged in this order from the plane surface of the substrate,
wherein the plane surface of the substrate comprises a first region overlapping the light emitting unit and a second region extending from the first region and located outside the light emitting unit,
wherein the semi-transparent reflecting layer is in contact with the plane surface of the substrate, and
wherein a light distribution of light from the light-emitting unit has a higher luminous intensity in a first direction compared to a reference direction, the reference direction being along a thickness direction of the light-emitting layer from the organic layer to the semi-transparent reflecting layer, and the first direction being different from the reference direction.
12. The light-emitting device according to claim 11 , further comprising k layers from a first layer to a k-th layer (k is an integer that is equal to or greater than 2) between the semi-transparent reflecting layer and the reflecting layer,
wherein a value ΔM defined by Formula (1) below is equal to or greater than in m−⅛ and equal to or less than m+⅛ (m is an integer that is equal to or greater than 1):
[
Formula
1
]
Δ
M
=
2
λ
∑
t
=
1
k
dt
n
t
2
-
n
0
2
sin
2
θ
0
+
1
2
π
(
ϕ
S
+
ϕ
R
)
(
1
)
λ: peak wavelength of light from the light-emitting unit
d i : thickness of i-th layer (1≤i≤k)
n i : refractive index of i-th layer (1≤i≤k)
n 0 : refractive index of medium propagated by light from the light-emitting layer
θ 0 : angle between the reference direction and a direction at which the light distribution has a maximum value
φS: phase shift amount of the semi-transparent reflecting layer
φR: phase shift amount of the reflecting layer.
13. The light-emitting device according to claim 11 ,
wherein the first direction inclines by an angle equal to or greater than 5 degrees and equal to or less than 60 degrees from the reference direction.
14. The light-emitting device according to claim 11 ,
wherein the light distribution has a maximum value in the first direction.
15. The light-emitting device according to claim 11 ,
wherein the light distribution has a higher luminous intensity compared to the reference direction in a second direction on an opposite side of the first direction with respect to the reference direction.
16. The light-emitting device according to claim 11 , further comprising a plurality of the light-emitting units and a plurality of light-transmitting units,
wherein the plurality of light-emitting units comprise a first light-emitting unit and a second light-emitting unit that is adjacent to the first light-emitting unit, and
wherein the plurality of light-transmitting units comprise a first light-transmitting unit between the first light-emitting unit and the second light-emitting unit.