Microscale Adaptive Optical Wavefront Correction

微尺度自适应光学波前校正

• 批准号: 0010026
• 负责人: Gert Cauwenberghs
• 金额: $ 30万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0010026&HistoricalAwards=false
• 关键词: Microscale; Adaptive; Optical; Wavefront; Correction

Phase distortions due to inhomogeneities in the optical path severely limit the perforinancc of a large class of optical systems for ground-to-ground and space communications, imaging through the atmosphere, medical laser beam focusing, among others. Demands on increased spatial resolutions and larger bandwidths call for an integrated approach to adaptive optics that modulates the wavefront in parallel at microscopic scale.This collaborative effort combines expertise in adaptive optics, analog parallel very-large scale integrated (VLSI) niicrosys-tems, microfabrication and liquid-crystal molecular systems to create a new generation of adaptive micro-optical systems for high-resolution wavefront correction, with over 10,000 fully autonomous control elements integrated on a single, hybrid opti-cal/electronic chip. Autonomy is essential for high-bandwidth operation, and is obtained by integrating all adaptive functions directly on-chip.At the architectural level, model-free adaptive control is implemented using parallel perturbation stochastic gradient descent optimization of an arbitrary, externally provided metric of system performance. At the physical level, high-speed wavefront control at micro-scale resolution is obtained by integrating a new type of fast nematic liquid-crystal (LC), operating at kilohertz- range bandwidths, onto the adaptive control chip. Silicon-on-sapphire (SoS) technology with ultra-thin silicon (UTSi) transis-tors provides a high-quality, low-noise, transparent active medium for high-density optical and electronic integration. We will investigate microscale structures of LC material sandwiched in between two transparent SoS wafers, implementing arrays of phase modulators with active electrodes implementing the adaptive algorithms in parallel. directly interfacing with the wave- front. The architectural and technological innovations combine to yield a projected system performance in excess of 108 control updates/sec. at least a factor 1,000 better than presently existing adaptive optics systems in speed, density and cost.This program integrates research and education in a sequence of project-intensive courses, where teams of graduate and undergraduate students learn to design. prototype and test adaptive optics co-processors, implemented in analog VLSI and fabricated through MOSIS. The adaptive co-processors will be configured to externally control a variety of fast LC and other spatial light phase modulators, available for experimentation at the Army Research Laboratory (ARL). In addition, we will make use of full-size UTSi SoS wafers provided by Peregrine Semiconductor, custom-fabricated in a special arrangement with Hopkins, to prototype a fully integrated version of consistent optical quality. The already polished SoS wafers will be post-processed at the JHU Microfabrication Laboratory and at Boulder Nonlinear Systems. Inc.. to pattern and deposit fast nematic LC in contact with SoS for fast spatial light phase modulation. The prototyped adaptive micro-optical systems will be experimentally demonstrated on various adaptive optics and imaging tasks including laser beam focusing and stabilization for optical communications.

由于光学路径中的不均匀性引起的相变畸形严重限制了一大类用于地面到地面和空间通信的大型光学系统的穿孔，通过大气中的成像，医疗激光束聚焦等。 Demands on increased spatial resolutions and larger bandwidths call for an integrated approach to adaptive optics that modulates the wavefront in parallel at microscopic scale.This collaborative effort combines expertise in adaptive optics, analog parallel very-large scale integrated (VLSI) niicrosys-tems, microfabrication and liquid-crystal molecular systems to create a new generation of adaptive用于高分辨率波前校正的微光学系统，超过10,000多个完全自主的控制元素集成在单个混合的Opti-Cal/电子芯片上。自治对于高带宽操作至关重要，可以通过直接在芯片上整合所有自适应功能来获得。在体系结构级别，使用平行扰动随机梯度下降优化了系统性能的任意外部提供的指标。在物理级别，通过在Kilohertz-Range带宽上运行的新型快速列表液晶（LC），可以在微尺度分辨率下进行高速波前控制。具有超薄硅（UTSI）转换的硅启用硅（SOS）技术提供了高质量，低噪声，透明的活性培养基，用于高密度光学和电子整合。我们将研究夹在两个透明的SOS晶状体之间的LC材料的显微镜结构，以实现并行实现自适应算法的活性电极实现相位调节器阵列。直接与波正面接口。架构和技术创新结合起来，产生超过108个控制更新/秒的预计系统性能。至少比目前现有的自适应光学系统要速度，密度和成本要好1,000个。该计划将研究和教育整合到一系列项目密集型课程中，毕业生和本科生的团队学会了设计。原型和测试自适应光学处理器，在模拟VLSI中实现，并通过Mosis制造。自适应协会将配置为外部控制各种快速LC和其他空间光相调节器，可在陆军研究实验室（ARL）进行实验。此外，我们将利用由Peregrine半导体提供的全尺寸UTSI SOS WAFER，并与霍普金斯（Hopkins）进行特殊安排进行定制制作，以原型类型制作完整的一致的光学质量。已经抛光的SOS晶圆将在JHU微加工实验室和Boulder非线性系统进行后处理。 Inc ..与SOS接触以进行快速空间光相调制以进行模式和沉积快速的列表。原型的自适应微光学系统将在各种自适应光学器件和成像任务上进行实验证明，包括激光束聚焦和光学通信的稳定化。