Xiong Zheng, Kunwar Puskal, Soman Pranav
Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA, 13244.
Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244.
Adv Opt Mater. 2021 Jan 18;9(2). doi: 10.1002/adom.202001217. Epub 2020 Nov 25.
Hydrogels, due to their optical transparency and biocompatibility, have emerged as an excellent alternative to conventional optical materials for biomedical applications. Advances in microfabrication techniques have helped convert conventional hydrogels into optically functional materials such as hydrogel-based diffraction optical elements (hDOEs). However, key challenges related to device customization and ease/speed of fabrication need to be addressed to enable widespread utility and acceptance of hDOEs in the field. Here, we report rapid printing of customized hDOEs on polyethylene glycol diacrylate (PEGDA) hydrogel using digital photopatterning; a novel method that combines simulated computer-generated hologram (SCGH) and projection photolithography. To showcase the versatility of this approach, a range of hDOEs are demonstrated, including 1D/2D diffraction gratings, Dammann grating, Fresnel zone plate (FZP) lens, fork-shaped grating and computer-generated hologram (CGH) of arbitrary pattern. Results demonstrate that printed hDOEs exhibit optical performance that is comparable with devices made with conventional materials. This versatile strategy can be potentially implemented with other photosensitive hydrogels to achieve user-defined hDOEs in a time-efficient and cost-effective fashion.
水凝胶因其光学透明性和生物相容性，已成为生物医学应用中传统光学材料的极佳替代品。微加工技术的进步有助于将传统水凝胶转化为光学功能材料，如水凝胶基衍射光学元件（hDOE）。然而，为了使hDOE在该领域得到广泛应用和认可，需要解决与器件定制以及制造的简便性/速度相关的关键挑战。在此，我们报告了使用数字光图案化技术在聚乙二醇二丙烯酸酯（PEGDA）水凝胶上快速打印定制的hDOE；这是一种将模拟计算机生成全息图（SCGH）和投影光刻相结合的新方法。为了展示这种方法的多功能性，展示了一系列hDOE，包括一维/二维衍射光栅、达曼光栅、菲涅耳波带片（FZP）透镜、叉形光栅和任意图案的计算机生成全息图（CGH）。结果表明，打印的hDOE表现出与传统材料制成的器件相当的光学性能。这种通用策略可以潜在地应用于其他光敏水凝胶，以高效且经济高效的方式实现用户定义的hDOE。
