Numerical simulation theory and structural optimization of a flexible AMOLED module subjected to the impact of a falling ball

Abstract

When the flexible active-matrix organic light-emitting diode (AMOLED) module is subjected to external impact, the key display device is easily damaged, so it is necessary to optimize the module structure to improve the impact resistance of the module. The adhesives in the module make the structural optimization of the module extremely complicated. In this paper, the viscoelastic and hyperelastic constitutive models of adhesives are established, and the method of simplifying the simulation model of the impact test is studied. Through the attenuation of the stress wave in the transmission, the reason why the dead pixels appear in the center of the module impacted by the ball is explained. According to the actual result that the area of dark spots does not expand with time, it is inferred that the AMOLED layer is damaged, and the maximum principal strain of that is extracted for analysis. In order to ensure the impact resistance of the module, the thickness of each layer should be increased to a certain extent. Slightly increasing the modulus of the film on the upper side of the AMOLED layer is likely to reduce the impact resistance of the module, whereas greatly increasing the modulus of that can improve the impact resistance of the module. An experimental method for determining the critical height of the falling ball is proposed, and it proves that the simulation theory and the optimization scheme are reasonable.