Oled microcavity design and optimization method

Abstract

Control of the emission characteristics of a light source in a light field display poses a significant benefit in the resulting 3D display quality for current and future technologies. A design system for microcavity OLEDs of any wavelength is detailed, which combines theoretical background with FDTD optimizations, permitting microcavity design of any OLED configuration. The resulting output profiles for microcavity OLEDs designed and fabricated with this method are compared to standard OLEDs and provide a reduction in spectral bandwidth, and a decrease in angular output.

1 . A microcavity OLED comprising:
 a stacked layer structure with a bottom reflective layer and Distributed Bragg Reflector (DBR) top layer configured to create a microcavity comprising a series of organic layers stacked in between a cathode layer and an anode layer to form a top emitting OLED tuned to emit a specified wavelength of light;   wherein the DBR top layer has a maximum reflectance at the Bragg wavelength and is configured for use with the top emitting OLED tuned to emit the specified wavelength of light and comprises sublayers of alternating dielectric material comprised of titanium dioxide and silicon dioxide, each sublayer thickness is a function of the Bragg wavelength.   
     
     
         2 . The microcavity OLED according to  claim 1 , wherein the Bragg wavelength does not equal the wavelength of the light that the OLED is tuned to emit. 
     
     
         3 . The microcavity OLED according to  claim 1 , wherein the DBR consists of six to twelve sublayers of alternating dielectric material. 
     
     
         4 . The microcavity OLED according to  claim 3 , wherein the DBR top layer comprises four pairs, four and half pairs, or five pairs of alternating dielectric material. 
     
     
         5 . (canceled) 
     
     
         6 . The microcavity OLED according to  claim 1 , wherein the DBR top layer comprises four three pairs of alternating titanium dioxide and silicon dioxide sublayers, has a Bragg wavelength of 525 nm, and wherein each titanium dioxide sublayer is about 52.4 nm thick and each silicon dioxide sublayer is about 90.5 nm thick. 
     
     
         7 . The microcavity OLED according to  claim 1 , wherein the OLED is tuned to emit red, green or blue light. 
     
     
         8 - 18 . (canceled) 
     
     
         19 . The microcavity OLED according to  claim 1 , further comprising a filler layer abutting the DBR top layer. 
     
     
         20 . The microcavity OLED according to  claim 1 , wherein the microcavity OLED emits one or more substantially collimated, manipulated, or tuned light beams, and the light beams propagate through a directional optical guiding surface 
     
     
         21 . A microcavity OLED comprising:
 a bottom reflective layer comprising a plurality of organic layers stacked between a cathode layer and an anode layer;   a filler layer above the bottom reflective layer; and   a top Distributed Bragg Reflector (DBR) layer comprising a stacked layer structure with alternating high and low refractive index dielectric layers comprised of titanium dioxide and silicon dioxide, the top DBR layer having a maximum reflectance and operatively tuned at the Bragg wavelength,   wherein the microcavity OLED emits one or more substantially collimated, manipulated, or tuned light beams at the Bragg wavelength.   
     
     
         22 . The microcavity OLED according to  claim 21 , wherein the top DBR layer has a Bragg wavelength of 525 nm and each titanium dioxide sublayer is about 52.4 nm thick and each silicon dioxide sublayer is about 90.5 nm thick. 
     
     
         23 . The microcavity OLED according to  claim 21 , wherein the layer thicknesses of the alternating high and low refractive index dielectric layers in the top DBR layer are chosen such that the optical path length of each layer is one quarter of the resonance wavelength of the specified wavelength. 
     
     
         24 . The microcavity OLED according to  claim 21 , wherein the top DBR layer comprises between 3-6 pairs of alternating high and low refractive index dielectric layers. 
     
     
         25 . The microcavity OLED according to  claim 21 , further comprising a directional optical guiding surface above the top DBR layer. 
     
     
         26 . The microcavity OLED according to  claim 21 , further comprising a plurality of bottom reflective layers and a single top DBR layer. 
     
     
         27 . A microcavity OLED comprising:
 a plurality of subpixels, each subpixel comprising:
 a bottom reflective layer comprising a plurality of organic layers stacked between a cathode layer and an anode layer; 
 a filler layer above the bottom reflective layer; and 
   a top Distributed Bragg Reflector (DBR) layer comprising a stacked layer structure with alternating high and low refractive index dielectric layers, the top DBR layer having a maximum reflectance and operatively tuned at the Bragg wavelength,   wherein the microcavity OLED emits one or more substantially collimated, manipulated, or tuned light beams at the Bragg wavelength.   
     
     
         28 . The microcavity OLED according to  claim 27 , wherein the top DBR layer has a Bragg wavelength of 525 nm and each titanium dioxide sublayer is about 52.4 nm thick and each silicon dioxide sublayer is about 90.5 nm thick. 
     
     
         29 . The microcavity OLED according to  claim 27 , wherein the layer thicknesses of the alternating high and low refractive index dielectric layers in the top DBR layer are chosen such that the optical path length of each layer is one quarter of the resonance wavelength of the specified wavelength. 
     
     
         30 . The microcavity OLED according to  claim 27 , wherein the top DBR layer comprises between 3-6 pairs of alternating high and low refractive index dielectric layers. 
     
     
         31 . The microcavity OLED according to  claim 30 , further comprising a directional optical guiding surface above the top DBR layer. 
     
     
         32 . The microcavity OLED according to  claim 30 , further comprising a plurality of bottom reflective layers and a single top DBR layer.