OLED microcavity design and optimization method
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 method of obtaining fabrication specifications and fabricating a microcavity OLED tuned to emit a specified wavelength of light, the microcavity OLED comprising material layers including microcavity layers and reflective layers, wherein said microcavity layers and reflective layers are configured to provide a cathode and an anode with organic layers disposed there between, an optional filler layer and a Distributed Bragg Reflector (DBR) of the microcavity OLED, the method comprising the computer-implemented steps of:
calculating optical path length and mirror reflectance approximations for the cathode and DBR for a given set of microcavity OLED emission characteristics;
applying a FDTD simulation to determine mirror penetration depths required for the microcavity OLED to emit the specified wavelength of light using the optical path length and mirror reflectance approximations;
applying a FDTD simulation to parameterize one or more of the material layers to be used to form the microcavity layers; and
using the results of the FDTD simulation to parameterize one or more of the material layers to determine the optimized thicknesses for the one or more materials layers and thereby provide fabrication specifications for the microcavity OLED.
2. The method of claim 1 , wherein the microcavity layers comprise organic layers.
3. The method of claim 2 , wherein applying a FDTD simulation to parameterize the organic layers is based on a particle swarm optimization protocol.
4. The method of claim 1 , wherein the microcavity layers comprise anode layers.
5. The method of claim 1 , wherein the microcavity layers comprise filler layers.
6. The method of claim 1 , wherein applying a FDTD simulation to determine mirror penetration depths is based on a transfer matrix protocol.
7. The method of claim 1 , further comprising fabricating the microcavity OLED.
8. The method of claim 7 , wherein the DBR has a Bragg wavelength configured for use with the microcavity OLED tuned to emit a specified wavelength of light, and comprises sublayers of alternating dielectric material, each sublayer's thickness providing an optical path length equal to one quarter of the Bragg wavelength.
9. The method of claim 8 , wherein the microcavity OLED is top-emitting.
10. The method of claim 8 , wherein the microcavity OLED is tuned to emit red, green or blue light.
11. The method of claim 8 , wherein the DBR comprises three pairs of alternating titanium dioxide and silicon dioxide sublayers, has a Bragg wavelength of 500 nm and wherein each titanium dioxide sublayer is about 50 nm thick and each silicon dioxide sublayer is about 86 nm thick.