Organic light-emitting device and light source apparatus using same
An organic light-emitting device including a first substrate, a second substrate, a light drawing-out layer disposed between the first substrate and the second substrate, a transparent electrode disposed between the light drawing-out layer and the first substrate, a reflection electrode disposed between the transparent electrode and the first substrate, and a first light-emitting unit disposed between the transparent electrode and the reflection electrode. The first light-emitting unit includes a first light-emitting layer that emits a first light-emitting color. In the organic light-emitting device, relations of the equation L 1 ≧λ 2 /4 and the equation L 1 cos θ 1 =λ 1 (¼+n/2) are satisfied, wherein L 1 is an optical length from a light-emitting point in the first light-emitting layer to the reflection electrode, λ 2 is a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of a light-emitting spectrum of the first light-emitting color, λ 1 is a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the first light-emitting color, n is an integer not less than 0, and 0 <θ 1 ≦60.
1. An organic light-emitting device comprising:
a first substrate;
a second substrate;
a light drawing-out layer disposed between the first substrate and the second substrate;
a transparent electrode disposed between the light drawing-out layer and the first substrate;
a reflection electrode disposed between the transparent electrode and the first substrate; and
a first light-emitting unit disposed between the transparent electrode and the reflection electrode;
wherein the light drawing-out layer includes particles and a binder;
wherein the particles have larger refractive index than the transparent electrode has;
wherein the first light-emitting unit includes a first light-emitting layer for emitting a first light-emitting color; and
wherein relations of equation (1) and equation (2) are satisfied:
L 1 ≧λ 2 /4 (1)
L 1 cos θ 1 =λ 1 (¼ +n/ 2) (2)
where L 1 is an optical length from a first light-emitting point in the first light-emitting layer to the reflection electrode,
where λ 2 is a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of a light-emitting spectrum of the first light-emitting color,
where λ 1 is a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the first light-emitting color,
where n is an integer not less than 0, and
where 0<θ 1 ≦60.
2. The organic light-emitting device according to claim 1 ,
wherein the first light-emitting unit further includes a second light-emitting layer for emitting a second light-emitting color, and
wherein relations of equation (3) and equation (4) are satisfied instead of the equation (1) and the equation (2), respectively:
L 2 ≧λ 4 /4 (3)
L 2 cos θ 2 =λ 3 (¼ +n/ 2) (4)
where L 2 is a shorter optical length when comparing an optical length from the first light-emitting point in the first light-emitting layer to the reflection electrode and an optical length from a second light-emitting point in the second light-emitting layer to the reflection electrode,
where λ 4 is a longer wavelength when comparing a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the first light-emitting color and a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of a light-emitting spectrum of the second light-emitting color,
where λ 3 is a shorter wavelength when comparing the wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the first light-emitting color and the wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color,
where n is an integer not less than 0, and
where 0<θ 2 ≦60.
3. The organic light-emitting device according to claim 2 ,
wherein the first light-emitting unit further includes a third light-emitting layer for emitting a third light-emitting color,
wherein a relation of equation (5) is satisfied instead of the equations (1) and (3), and
wherein a relation of equation (6) is satisfied instead of the equations (2) and (4):
L 3 ≧λ 6 /4 (5)
L 3 cos θ 3 =λ 5 (¼ +n/ 2) (6)
where L 3 is a shortest optical length when comparing an optical length from the first light-emitting point in the first light-emitting layer to the reflection electrode, an optical length from the second light-emitting point in the second light-emitting layer to the reflection electrode, and an optical length from a third light-emitting point in the third light-emitting layer to the reflection electrode,
where λ 6 is a longest wavelength when comparing a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the first light-emitting color, a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color, and a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the third light-emitting color,
where λ 5 is a shortest wavelength when comparing a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the first light-emitting color, a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity on the light-emitting spectrum of the second light-emitting color, and a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the third light-emitting color,
where n is an integer not less than 0, and
where 0<θ 3 ≦60.
4. The organic light-emitting device according to claim 3 , wherein
the first light-emitting color is blue,
the second light-emitting color is green,
the third light-emitting color is red, and
the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer are disposed in this order from the reflection electrode to the transparent electrode.
5. The organic light-emitting device according to claim 1 , further comprising:
a second light-emitting unit disposed between the transparent electrode and the reflection electrode; and
a charge generating layer disposed between the first light-emitting unit and the second light-emitting unit;
wherein the second light-emitting unit includes a second light-emitting layer for emitting a second light-emitting color, and
wherein relations of equation (7) and equation (8) are satisfied:
L 4 ≧λ 8 /4 (7)
L 4 cos θ 4 =λ 7 (¼ +n/ 2) (8)
where L 4 is an optical length from a light-emitting point in the second light-emitting layer to the reflection electrode,
where λ 8 is a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of a light-emitting spectrum of the second light-emitting color,
where λ 7 is a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color,
where n is an integer not less than 0, and
where 0<θ 4 ≦60.
6. The organic light-emitting device according to claim 5 ,
wherein the second light-emitting unit further includes a third light-emitting layer for emitting a third light-emitting color, and
wherein relations of equation (9) and equation (10) are satisfied instead of the equation (7) and the equation (8), respectively:
L p1 ≧λ p2 /4 (9)
L p1 cos θ p1 =λ p1 (¼ +n/ 2) (10)
where L p1 is a shorter wavelength when comparing an optical length from the second light-emitting point in the second light-emitting layer to the reflection electrode and an optical length from a third light-emitting point in the third light-emitting layer to the reflection electrode,
where λ p2 is a longer wavelength when comparing a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color and a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the third light-emitting color,
where λ p1 is a shorter wavelength when comparing a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color and a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the third light-emitting color,
where n is an integer not less than 0, and where 0<θ p1 ≦60.
7. The organic light-emitting device according to claim 6 , wherein
the first light-emitting color is blue, and
one of the second light-emitting color and the third light-emitting color is red and the other of them is green.
8. The organic light-emitting device according to claim 1 ,
wherein the first light-emitting unit includes a second light-emitting layer for emitting a second light-emitting color, and
wherein relations of equation (11) and equation (12) are satisfied:
L 5 ≧λ 10 /4 (11)
L 5 cos θ 1 =λ 9 (¼ +n/ 2) (12)
where L 5 is an optical length from the second light-emitting point in the second light-emitting layer to the reflection electrode,
where λ 10 is a wavelength at the longer wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color,
where λ 9 is a wavelength at the shorter wavelength side, having an intensity of 1% of the maximum intensity of the light-emitting spectrum of the second light-emitting color,
where n is an integer not less than 0, and
where 0<θ 5 ≦60.
9. The organic light-emitting device according to claim 1 , wherein
the light drawing-out layer is bonded to the second substrate by an adhesive layer.
10. The organic light-emitting device according to claim 1 , wherein
the first light-emitting unit further includes a hole transport layer, an electron transport layer, a buffer layer, a hole injection layer, and an electron injection layer.
11. A light source apparatus, comprising:
the organic light-emitting device according to claim 1 ; and
a driving device.