Large area OLEDs aimed at lighting applications should provide homogeneous luminance—homogeneity
is one of the quality metrics of such devices. Local light generation depends on both
the local temperature and the local voltage drop across the light emitting polymer(s)
in the device. Therefore the thermal and electrical engineering of OLEDs aimed at
lighting applications is critical. Due to the large area of these devices the coupled
electrical and the thermal simulation problem is of distributed nature. Electrical
characteristics of organic semiconductor materials used in OLED devices are highly
nonlinear, and their nonlinear temperature-dependence is significant. In our present
approach to distributed electro-thermal field simulation we address special needs
of OLEDs, which is not yet the case with widely used, commercially available simulation
tools. In this paper we present the latest version of our SUNRED electro-thermal field
solver algorithm capable of handling coupled, non-linear electro-thermal problems.
The new features of the algorithm are demonstrated by modeling some research OLED
samples available to us in the Fast2Light project—this way simulation results are
compared against measured data.