压印成型条件对微透镜结构影响的模拟

The Simulation of the Effect of Embossing Molding Conditions on the Micro Structure

利用Polyflow模拟热压印中微结构的充模过程,并以微透镜为例研究了在热压印中高分子材料在微结构充模时,压印温度、压力、速度、孔的大小、基片厚度等物理量变化对微透镜成型结构的影响规律。模拟结果表明,微透镜在成型初期,不同位置的曲率半径不同;随着压印过程的进行,各个位置的曲率半径逐渐减小最终趋于一致;压印速度越快,压印成型时间越短;多孔压印比单孔压印所需的时间要长;同时减小孔间距,孔周围流体速度增加,将影响微透镜成型的均匀性;增加基片厚度对曲率的减小影响甚微,靠增加基片厚度缩短成型时间的效果不太明显。

The microstructure mold filling process of hot pressing was simulated by Polyflow. As a case study of the thermal printing of polymer materials when molding, the influences of embossing temperature, pressure, speed, the size of the hole, the thickness of the substrate on micro lens structure forming were studied. The simulation results show that at the beginning of the micro lenses forming, the radius of curvature is different at the different location. Faster the embossing speed is, shorter the stamping time is. The stamping time of porous imprint is longer than that required for a single hole imprint. At the same time reducing hole distance, fluid velocity around the hole increases, which will affect the uniformity of micro lens. Increasing the substrate thickness has little effect on the decrease of the curvature, and it＇s not obvious to reduce molding time by increasing the thickness of the substrate.