Microlenses can be widely used in integrated micro-optical systems. However, in some special applications, such as light field imaging systems, multifocal microlens arrays (MLA) are expected to improve imaging resolution. For the fabrication of multifocal MLA, the traditional fabrication method is no longer applicable. To solve this problem, a fabrication method of multifocal MLA by a one step exposure process is proposed. Through the analyses and research of photoresist AZ9260, the nonlinear relationship between exposure dose and exposure depth is established. In the design of the mask, the mask pattern is corrected according to the nonlinear relationship to obtain the final mask. The continuous surface of the multifocal MLA is fabricated by the mask moving exposure. The experimental results show that the prepared multifocal MLA has high filling factor and surface fidelity. What is more, this method is simple and efficient to use in practical applications.

中文翻译：

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一步曝光法制备多焦微透镜阵列

微透镜可广泛应用于集成微光学系统。然而，在一些特殊应用中，例如光场成像系统，多焦点微透镜阵列 (MLA) 有望提高成像分辨率。对于多焦点MLA的制造，传统的制造方法已不再适用。为了解决这个问题，提出了一种通过一步曝光工艺制造多焦点MLA的方法。通过对AZ9260光刻胶的分析研究，建立了曝光剂量与曝光深度的非线性关系。在掩模设计中，根据非线性关系修正掩模图形，得到最终掩模。多焦点 MLA 的连续表面是通过掩模移动曝光制造的。实验结果表明，制备的多焦点MLA具有较高的填充因子和表面保真度。更重要的是，这种方法在实际应用中简单有效。