Transparent Light-Emitting Component

• US 20060284170A1
• Filed: 05/25/2006
• Published: 12/21/2006
• Est. Priority Date: 05/27/2005
• Status: Active Grant

• Current Assignee: Novaled AG
• Original Assignee: Novaled AG
• Inventors: Leo, Karl, Lyssenko, Vadim, Gelhaar, Robert
• Granted Patent: US 7,598,519 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/856 comprising reflective means

Abstract

The invention concerns a transparent light-emitting component, in particular an organic light-emitting diode (OLED), with a layer arrangement in which a light-emitting organic layer is arranged between an upper and a lower electrode, the layer arrangement being transparent in a switched-off state and emitting light which is produced in the light-emitting organic layer by applying an electric voltage to the upper and the lower electrode in a switched-on state, which light is radiated in a ratio of at least approximately 4:1 through the upper or the lower electrode and where a stack, which is transparent in the visible spectral region, of dielectric layers is arranged on the side of the upper or the lower electrode.

Claims

1. Transparent light-emitting component, in particular organic light-emitting diode (OLED), with a layer arrangement in which a light-emitting organic layer is arranged between an upper and a lower electrode, the layer arrangement being transparent in a switched-off state and emitting light which is produced in the light-emitting organic layer by applying an electrical voltage to the upper and the lower electrode in a switched-on state and which is radiated, which light is radiated in a ratio of at least approximately 4:

1 through the upper or the lower electrode, characterized in that a stack, which is transparent in the visible spectral region, of dielectric layers of two or more materials with different refractive indices is arranged on the side of the upper or the lower electrode.

2. Transparent light-emitting component according to claim 1, characterized in that the emission spectrum of the light which is produced in the light-emitting organic layer and a spectral reflection region of the stack of dielectric layers, in which the stack of dielectric layers has a high reflecting power (>

90%), are formed so as to be at least partly overlapping.

3. Transparent light-emitting component according to claim 1 characterized in that the dielectric layers in each case have a layer thickness of (n×

λ

/4), wherein n=1,2, . . . and λ

is a wavelength of the emitted light.

4. Transparent light-emitting component according to claim 1, characterized in that the stack of dielectric layers is applied directly to the upper or the lower electrode.

5. Transparent light-emitting component according to claim 1, characterized in that the light-emitting organic layer is formed as a layer sequence with a plurality of layers.

6. Transparent light-emitting component according to claim 1, characterized in that the layer arrangement is formed to emit white light, the white light being composed of a plurality of spectral components of the light which is produced in the light-emitting organic layer.

7. Transparent light-emitting component according to claim 1, characterized in that different orders of the stack of dielectric layers are used for reflection by the stack for different spectral components of the light which is produced in the light-emitting organic layer, so that a plurality of reflection bands can he used with the stack having uniform layer thickness.

8. Transparent light-emitting component according to claim 1, characterized in that the light-emitting organic layer is formed in an organic light-emitting diode, and that at least one further organic light-emitting diode with a further light-emitting organic layer is formed, the organic light-emitting diode and the at least one further organic light-emitting diode being stacked one on top of the other.

9. Transparent light-emitting component according to claim 1, characterized in that at least a part of the dielectric layers of the stack of dielectric layers has a different refractive index in each case.

10. Transparent light-emitting component according to claim 1, characterized in that a modulated refractive index distribution is formed for at least one part of the dielectric layers in the stack of dielectric layers.

11. Transparent light-emitting component according to claim 10, characterized in that the modulated refractive index distribution is formed in an essentially oscillating manner.

12. Transparent light-emitting component according to claim 1, characterized in that a sequence of continually increasing/decreasing refractive indices is formed for at least one part of the dielectric layers in the stack of dielectric layers.