ORGANIC ELECTROLUMINESCENT DISPLAY

• US 20120018712A1
• Filed: 07/19/2011
• Published: 01/26/2012
• Est. Priority Date: 07/21/2010
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hamaguchi, Atsushi, Mizuno, Nobutaka
• Granted Patent: US 8,618,559 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H10K 2102/351 Thickness
• CPC Class Codes: H10K 50/14 Carrier transporting layers
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/353 characterised by the geometrical arrangement of the RGB subpixels
• CPC Class Codes: H10K 59/80518 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 59/876 comprising a resonant cavity structure, e.g. Bragg reflector pair

Abstract

An organic electroluminescent (EL) display includes a plurality of organic EL devices for red, green, and blue subpixels, each including a first electrode on a light output side, a second electrode opposite the first electrode, and an organic compound layer including a light-emitting layer therebetween. The organic EL devices have a resonator structure between a first reflective surface closer to the first electrode than the organic compound layer and a second reflective surface closer to the second electrode than the organic compound layer. A predetermined white color is displayed by mixing the three colors such that an optical distance of the organic EL devices of each color between an emission position in the light-emitting layer and the second reflective surface is set within ±10% from an optical distance corresponding to an nth-order minimum of a curve of required current density against at least the optical distance.

Claims

1. An organic electroluminescent display comprising:

a plurality of organic EL devices for red, green, and blue subpixels, each including a first electrode on a light output side, a second electrode opposite the first electrode, and an organic compound layer including a light-emitting layer therebetween, the organic EL devices having a resonator structure configured to resonate light emitted from the light-emitting layer between a first reflective surface closer to the first electrode than the organic compound layer and a second reflective surface closer to the second electrode than the organic compound layer,

wherein a predetermined white color is displayed by mixing the three colors such that an optical distance of the organic EL devices of each color between an emission position in the light-emitting layer and the second reflective surface is set within ±

10% from an optical distance corresponding to an nth-order minimum of a curve of required current density against at least the optical distance.

2. The organic electroluminescent display according to claim 1, wherein the optical distance for each color is set on the basis of a second-order minimum of the curve of required current density.

3. The organic electroluminescent display according to claim 1, wherein an optical distance of the organic EL devices of each of the three colors between the first and second reflective surfaces is set within ±

10% from an optical distance corresponding to an nth-order minimum of a curve of required current density against the optical distance between the emission position in the light-emitting layer and the second reflective surface and an optical distance between the emission position in the light-emitting layer and the first reflective surface.