Advancing the Manufacturing of High Precision Optics by Replication in Different Substrate Materials

9632929李将开发两种新的复制技术，以降低制造精密衍射光栅和光学、二元光学、微型光学和计算机生成全息图的成本。当它们是非中心对称的、它们的孔径区域不是圆形的(例如正方形或六边形)、和/或它们是具有精确的中心到中心间隔的阵列格式时，这些复制技术将特别地显示它们的优点。第一种技术可用于在环境耐用的衬底上复制红外和可见光精密光学元件。它需要首先用电子束的一个写入步骤通过在空间上控制电子剂量来产生灰度级掩模。然后，使用这种灰度级掩模，它只需要对每个拷贝进行一次迭代，即通过化学辅助离子束刻蚀(CAIBE)曝光模拟光刻胶并将模拟光刻胶图案转移到衬底中。由于可以同时刻蚀多个基板，因此CAIBE是一种批量工艺，降低了每个副本的刻蚀成本。此外，由于利用投影对准器可以反复使用相同的灰度级蒙版来制作多个副本，因此生成灰度级蒙版的成本将分摊到副本数上。衍射光学的复制品可以在不同的(红外-UV)衬底材料中。第二种复制技术从石英或玻璃上的母版开始。复制品是由液体光致聚合物通过模塑制成的。曲面或集成容器上的衍射光学元件可以用液体光致聚合物复制，以在可见光范围内工作。能够在曲面上放置衍射光学元件为光学设计者提供了消除像差的额外自由度；能够通过集成插座复制衍射光学元件降低了组装成本。换句话说，我们的总体技术目标将是展示这两种复制技术在不同材料中的可行性，以及研究制造问题。几家行业合作者对拟议中的调查表现出了强烈的兴趣。总体工作将大致如下：70%用于第一种复制技术，30%用于第二种复制技术。

9632929 Lee Two new replication techniques will be developed to reduce the costs of manufacturing precision diffractive gratings and optics, binary optics, micro-optics and computer generated holograms. These replication techniques will show their advantages specially when they are non centro-symmetric, their aperture areas are not circular (e.g. square or hexagonal), and/or they are in an array format with precise center-to center spacings. The first technique can be applied to replicate infrared as well as visible-uv precision optics on environmentally durable substrates. It requires first generating a gray level mask with only one writing step of an electron beam by controlling the electron dosage spatially. Then, using this gray level mask, it requires for each copy only one iteration of exposing the analog photoresist and transferring the analog photoresist pattern into the substrate by chemically assisted ion beam etching (CAIBE). Since multiple substrates can be etched simultaneously, the CAIBE is a batch process and the etching cost for each copy is reduced. Moreover, since the same gray level mask can be used over and over again for making many copies with a projection aligner, the cost of generating the gray level mask will be spread over the number of copies. The copies of diffractive optics can be in different (infrared-uv) substrate materials. The second replication technique starts with a master on quartz or glass. Replica are made from liquid photopolymer by molding. Diffractive optics on curved surfaces or with integrated receptacles can be replicated with liquid photopolymer to work in the visible range. Being able to put diffractive optics on curved surfaces allows the optical designers additional degrees of freedom for aberration removal; being able to replicate diffractive optics with integrated receptacles reduces the assembly costs. In other words, our overall technical objectives will be demonstrating the feasibility of these two replication techniques in different mater ials as well as studying the manufacturing issues. Several industrial collaborators have shown strong interests in the proposed investigations. The overall effort will be divided approximately as follows: 70% to the first replication technique and 30% to the second.