Hot embossing has been widely used in fabricating microlens arrays because of its low cost, high efficiency, and high quality. The process parameters such as molding temperature, molding pressure, and holding temperature affect the microlens array’s replication quality. This work selected the stainless steel S136H tool steel as the mold material to process an aspheric microlens array structure through ultra-precision milling. Polymethyl methacrylate (PMMA) microlens arrays with different surface replication were prepared by controlling the molding temperature, molding pressure, and holding temperature. By analyzing the surface quality, contour replication, and optical imaging of hot-embossed samples, the optimal molding temperature of PMMA for optimal replication of aspheric lens arrays was determined as 130 °C. Besides, the internal elastic recovery of PMMA affected the dimensional accuracy and optical performance of the lens. The results showed that, at the molding pressure of 400 N and the holding temperature of 60 °C, the surface defects were eliminated, and the aspheric lens array had perfect replication with a profile deviation of only 4 μm. The aspheric microlens array with good quality was eventually achieved by these optimal process parameters, which provides a foundation for producing aspheric microlens arrays in a low-cost and high-efficiency way.

中文翻译：

---

热压技术制备聚合物非球面微透镜阵列及其光学特性

热压印由于其低成本，高效率和高质量而已被广泛用于制造微透镜阵列。诸如模制温度，模制压力和保持温度的工艺参数会影响微透镜阵列的复制质量。这项工作选择了不锈钢S136H工具钢作为模具材料，通过超精密铣削加工非球面微透镜阵列结构。通过控制成型温度，成型压力和保持温度，制备了具有不同表面复制率的聚甲基丙烯酸甲酯（PMMA）微透镜阵列。通过分析热压花样品的表面质量，轮廓复制和光学成像，确定用于非球面透镜阵列最佳复制的PMMA最佳成型温度为130°C。除了，PMMA的内部弹性恢复会影响镜片的尺寸精度和光学性能。结果表明，在400 N的成型压力和60°C的保持温度下，消除了表面缺陷，并且非球面透镜阵列具有完美的复制，其轮廓偏差仅为4μm。这些最优的工艺参数最终实现了高质量的非球面微透镜阵列，这为以低成本，高效率的方式生产非球面微透镜阵列奠定了基础。