Method of and system for simulating a light-emitting device

• US 7,676,354 B2
• Filed: 08/13/2008
• Issued: 03/09/2010
• Est. Priority Date: 11/30/2006
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nakamura, Hajime
• Primary Examiner(s): Rodriguez; Paul L
• Assistant Examiner(s): Jacob; Mary C
• Application Number:
  US12/191,224
• Publication Number:
  US 20090055151A1
• Time in Patent Office: 573 Days
• Field of Search: 703/13
• US Class Current: 703/13
• CPC Class Codes: G06F 2111/08 Probabilistic or stochastic CAD
• CPC Class Codes: G06F 2111/10 Numerical modelling
• CPC Class Codes: G06F 2119/06 Power analysis or power optimisation
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30

Abstract

A system for simulating a characteristic of a light-emitting device includes a transport calculating module for calculating a concentration of carriers in the light-emitting device. The system includes an optical calculating module for calculating data sets including a total emission power factor of excitons set and a light extraction efficiency data. A diffusion calculating module uses the exciton formation rate and the total emission power factor to calculate a concentration of excitons and a total deactivation rate of the excitons. A device characteristics calculating module uses the light extraction efficiency data set and a radiative deactivation rate calculated from the total deactivation rate to calculate a device characteristic of the light-emitting device.

Claims

1. A method of simulating an optical performance of an organic electroluminescence device executed by a computer device, comprising:

calculating, in the computer device, a concentration distribution of carriers to be supplied from an anode and a cathode of the organic electroluminescence device wherein the organic electroluminescence device includes an optical material comprising a plurality of optical material layers;

calculating a carrier recombination rate as an exciton formation rate in the computer device based on positions of excitons within the organic electroluminescence device;

reading stored optical data from the computer device that provides an optical characteristic of each optical material layer including an emission layer of the organic electroluminescence device;

calculating from the read optical data, a total emission power factor defined as a function of position coordinates of power of excitons within the organic electroluminescence device, which are deactivated due to light radiation;

calculating from the read optical data color space data for calculating a photometric quantity defined as a function of a position coordinate of an emitted light of excitons;

calculating a total deactivation rate factor of excitons including a loss due to a nonradiative transition process using the total emission power factor and the excitation formation rate;

summing a light extraction efficiency and a spectral emission intensity of excitons over a wavelength region associated with the optical material of the organic electroluminescence device;

calculating from the read optical data, a space profile of a concentration of excitons for the organic electroluminescence device; and

simulating an optical performance of the organic electroluminescence device by calculating a light-emitting characteristic and a quantum efficiency emission of excitons to be formed by the carrier recombination rate, by using the radiation deactivation rate, the summed light extraction efficiency and spectral emission intensity, and the concentration of excitons and storing the calculated light-emitting characteristic and the quantum efficiency emission of excitons to be formed by the carrier recombination rate.

2. A simulation method allowing a computer device to calculate a simulated performance of optical characteristics of an organic electroluminescence device, allowing the computer device to execute:

reading optical data from a database in the computer device that includes an optical characteristic of each layer including an emission layer of the organic electroluminescence device, and calculating a ratio of dipole moment in parallel to a light-emitting face of the organic electroluminescence device based on the optical data;

calculating a first data set of a light extraction efficacy of light emitted toward the light-emitting face that is defined as a function of a wavelength and position coordinates within the organic electroluminescence device;

storing the first data set in the computer device;

summing the light extraction efficiency and a spectral emission intensity of excitons over a wavelength region;

calculating a second data set of a power emission factor that is defined as a function of the position coordinate of excitons inside the organic electroluminescence device;

storing the second data set to be readable in the computer device for use in calculating a space profile of exciton concentration including calculation of a total deactivation rate factor of excitons including a loss due to a nonradiative transition process using the power emission factor and a carrier recombination rate obtained by calculating a concentration distribution of carriers supplied and transported from an anode and a cathode of the organic electroluminescence device;

calculating a third data set including color-space coordinate values of a color space as a function of the position coordinate of excitons inside the organic electroluminescence device; and

calculating within the computer device, the simulated performance of the optical characteristics of the organic electroluminescence device using the first, second, and third data sets and storing the calculated simulated performance of the optical characteristics of the organic electroluminescence device.

3. The simulation method according to claim 2 further allowing the computer device to execute:

summing the third data set over a wavelength region, thereby calculating a light-emitting characteristic at a position coordinate in the electroluminescence device from the third data set.