A New Approach for Fabricating Large Format Deformable Mirrors

自适应光学（AO）是一种在使用天文望远镜时消除大气造成的模糊的技术。作为望远镜的一部分，高速反射镜可以改变形状（即可变形反射镜），可以实现这种技术，从而产生更清晰的图像。这个项目将寻求开发一种制造这种可变形镜子的新方法。这种整合将允许在望远镜中更常规地使用AO。这种方法的一个关键任务是制造薄的弯曲玻璃“壳”，这是可变形光学反射镜的一部分。研究人员将开发一种更经济的方法来制造这些外壳。该项目将开发制造直径达0.9米的外壳的方法。这将使现有的大型望远镜能够利用这种光学器件用于天文学。该项目将有一名研究生参与开发工作。该项目将研究一种制造自适应次镜所需外壳的新方法。通常，最初平坦的抛光玻璃片通过加热形成曲线。这种方法将依赖于一个精确的负形式来使玻璃跌落。这个项目将采取一种不同的方法，让玻璃在外壳最终光学直径之外的支撑环内自由坍落。这种方法允许在各种曲率半径上创建壳体，只需调整峰值温度。为了创造一个近似抛物线的形状，需要一个额外的力，在光学直径外施加一个给定的力来完成顶部重量，从而创造出接近所需形状。这种制造更简单、更坚固的大口径可变形镜的能力，将使这种技术适用于各种口径的望远镜。这种制造方法也可以应用于天文学以外的其他应用，这些应用需要大型弯曲和可变形的光学器件，如太阳能集中光伏发电系统。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Adaptive Optics(AO) is a technique that removes the blurring created by the atmosphere when using an astronomical telescope. High speed mirrors, included as part of the telescope, that can change shape (i.e. deformable mirrors) can enable this technique, resulting in a much sharper image. This project would look to develop a new approach to making such deformable mirrors. This integration would allow for the more routine use of AO in telescopes. A key task for this approach is the fabrication of thin curved glass “shells” that are part of the deformable mirror optics. The investigators will develop a more economical way of making these shells. The program will develop the approach for making shells up to 0.9 m in diameter. This will enable existing large telescopes to utilize such optics for use in astronomy. The project will involve a graduate student in the development work.This project will investigate a new approach for fabrication of the shells needed to use in Adaptive Secondary Mirrors. Typically, initially flat polished sheets of glass are formed into curves via heating. This approach would rely on an accurate negative form to slump the glass onto. This project would take a different approach by letting the glass slump freely within a support ring that is outside the final optical diameter of the shell. Such an approach allows for creation of shells over a variety of radii of curvature, simply by adjusting the peak temperature. To create an approximately parabolic shape, an additional force is required that is accomplished with a top weight with a given force just outside the optical diameter creates close to the desired shape. This ability to fabricate simpler and more robust large format deformable mirrors, will make such technology available to a wide range of telescopes of various aperture sizes. This fabrication approach can also be applied to other applications beyond astronomy that require large curved and deformable optics such as solar concentrated photovoltaic power systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.