Qiu Jinfeng, Li Mujun, Ye Huichun, Yang Chen, Shi Cuicui
Appl Opt. 2018 Sep 1;57(25):7296-7302. doi: 10.1364/AO.57.007296.
We demonstrate a simple, controllable, and stable method for fabricating high fill factor cylindrical microlens array with a novel isolated thermal reflow process. In this method, microstripes with a very small gap were obtained via digital micromirror device-based lithography, then covered with polydimethylsiloxane (PDMS) solution. The prepared microstripes were isolated and were heated and reflowed to a cylindrical microlens array. During the reflow process, the semicross-linked PDMS can serve as a barrier to prevent the diameter change and the bonding of adjacent microlenses. By this special treatment, the fill factor of the cylindrical microlens array can be significantly improved. Moreover, the reflow time and temperature have very little effect on the microlens shape due to the surrounded semicross-linked PDMS. This will make our process stabler than traditional methods. The measured 3D profile is good and satisfactory, and excellent optical performance is demonstrated with the fabricated cylindrical microlens arrays. The proposed method may offer a viable route for fabrication of high fill factor microlens arrays in a very simple and stable way.
我们展示了一种通过新颖的孤立热回流工艺制造高填充因子圆柱形微透镜阵列的简单、可控且稳定的方法。在该方法中，通过基于数字微镜器件的光刻技术获得具有非常小间隙的微条纹，然后用聚二甲基硅氧烷（PDMS）溶液覆盖。制备的微条纹被隔离，并加热回流成圆柱形微透镜阵列。在回流过程中，半交联的PDMS可作为屏障，防止相邻微透镜的直径变化和粘结。通过这种特殊处理，圆柱形微透镜阵列的填充因子可得到显著提高。此外，由于周围的半交联PDMS，回流时间和温度对微透镜形状的影响非常小。这将使我们的工艺比传统方法更稳定。测量得到的三维轮廓良好且令人满意，所制造的圆柱形微透镜阵列展示出优异的光学性能。所提出的方法可能为以非常简单和稳定的方式制造高填充因子微透镜阵列提供一条可行的途径。
