基于力学理论的柔性显示模组的应变测量方法

Film strain measurement method of flexible display modules based on mechanical theory

柔性有机发光二极管(OLED)显示模组一般由各膜层与之间的粘合胶组成,在折叠过程中膜层易发生破坏.为了确保模组的可靠性,需要基于实验测量膜层应变,然而当前的应变测量方法并不适用于OLED模组中各膜层的应变测量.本文基于电子计算机断层扫描法测量了OLED模组弯折之后各膜层的相对滑移量,根据力学理论推导了相对滑移量与应变的关系,通过测量各膜层之间的相对滑移量间接获得了各膜层的应变,为应变测量提供了一种新方法.然后与模拟结果对比,相互验证确定了材料参数的准确性与应变测量理论的可靠性.最后探究了应变测量准确性的影响因素,分析表明,为确保应变测量的精度,应尽可能地获得弯折刚完成时的应变,并保证模组与框架的紧密粘合.

The flexible organic light-emitting diode(OLED)display modules are composed of films and adhesives,and the films are prone to damage during the folding process.To ensure the trouble-free use of the module,it is necessary to measure the film strain experimentally,but current methods are not suitable for the strain measurement of each film in the OLED module.In this paper,the relative slips among various films of the OLED module are measured based on the computed tomography method,and the relationship between the relative slips and strains is deduced according to mechanical theory.The strain of each film is indirectly obtained by measuring the relative slips among various films,providing a new method for strain measurement.Then,it is compared with the simulation results,so the accuracy of material parameters and the reliability of strain measurement theory are verified.Finally,the factors affecting the accuracy of the strain measurement method are explored.The analysis shows that the accuracy of strain measurement is ensured by the strain right after the module stops bending and the seamless adhesion between the module and frame.