Microcavity OLEDS for Lighting

Abstract

Various methods and systems are provided for related to organic light emitting diodes (OLEDs) having a microcavity. In one embodiment, a white-light source includes a first microcavity organic light emitting diode (OLED) configured to emit a narrow spectrum of blue light; a second microcavity OLED configured to emit a narrow spectrum of green light, and a third microcavity OLED configured to emit a narrow spectrum of red light. In another embodiment, a light source includes a plurality of OLEDs disposed on a glass substrate. Each of the OLEDs is configured to emit light in substantially orthogonal to the glass substrate in a predefined spectrum. Each of the OLEDs includes a semi-reflecting mirror; and an emitting layer, where the emitting layer in each OLED corresponds to a respective color of light emitted by the OLED.

Therefore, at least the following is claimed: 
     
         1 . A light source, comprising:
 a plurality of OLEDs disposed on a glass substrate, wherein each of the plurality of OLEDs is configured to emit light in substantially orthogonal to the glass substrate in a predefined spectrum, wherein each of the plurality of OLEDs comprises:
 a semi-reflecting layer; and 
 an emitting layer, wherein the emitting layer in each OLED corresponds to a respective color of light emitted by the OLED. 
   
     
     
         2 . The light source of  claim 1 , wherein the semi-reflecting layer includes a quarter wave stack. 
     
     
         3 . The light source of  claim 1 , wherein the semi-reflecting layer includes a layer having a low refractive index formed on a layer having a high refractive index. 
     
     
         4 . The light source of  claim 1 , wherein the semi-reflecting layer includes a plurality of silicon dioxide layers alternating with a plurality of titanium dioxide layers. 
     
     
         5 . The light source of  claim 1 , wherein the semi-reflecting layer includes a silver film. 
     
     
         6 . The light source of  claim 1 , wherein each of the OLEDs further comprises:
 a cathode formed on an electron transport layer, wherein the electron transport layer is formed on the emitting layer;   a hole transport layer formed on an indium tin oxide (ITO) layer, wherein the emitting layer is formed on the hole transport layer; and   wherein the ITO layer is formed on the semi-reflecting layer.   
     
     
         7 . The light source of  claim 6 , wherein the electron transport layer includes a 2,9-dimethly-4,7-diphenyl-1, 10-phenanthroline (BCP) layer or a tris[3-(3-pyridyl)-mesityl]borane (“3TPYMB”) layer. 
     
     
         8 . The light source of  claim 6 , wherein the cathode includes cesium carbonate (CsCO 3 ) and aluminum (Al) or lithium fluoride (LiF) and Al. 
     
     
         9 . The light source of  claim 6 , wherein the hole transport layer includes 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC). 
     
     
         10 . The light source of  claim 1 , wherein the emitting layer of a first OLED included in the plurality of OLEDs includes 3,5′-N,N′-dicarbazole-benzene (“mCP”) doped with tris(2-phenylisoquinoline)iridium (“Ir(pig) 3 ”). 
     
     
         11 . The light source of  claim 10 , wherein the emitting layer of a second OLED included in the plurality of OLEDs includes mCP doped with fac-tris(2-phenylpyridinato)iridium(III) (“Ir(ppy) 3 ”). 
     
     
         12 . The light source of  claim 11 , wherein the emitting layer of a third OLED included in the plurality of OLEDs includes mCP:Iridium(III)bis[(4,6-di-flourophenyl)-pyridinato-N,C2′] picolinate (“Flrpic”). 
     
     
         13 . The light source of  claim 1 , wherein each of the OLEDs includes a microcavity defined by the semi-reflecting layer and a cathode.