Large-aperture electrically tunable lenses with 1ms hysteresis-free response for remote focusing

大光圈电动可调镜头，具有 1ms 无迟滞响应，适用于远程对焦

• 批准号: 9255237
• 负责人: Janelle Claire Shane
• 金额: $ 15万
• 依托单位: BOULDER NONLINEAR SYSTEMS, INC.
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9255237
• 关键词: Back; Brain; Caliber; Characteristics; Custom; Development; Devices; Electrodes; Evaluation; Feedback; Financial compensation; Image; Length; Licensing; Light; Link; Liquid substance; Location; Measurement; Mechanics; Methods; Microscope; Microscopy; Motion; Movement; Neurons; Performance; Phase; Positioning Attribute; Procedures; Process; Sampling; Scanning; Speed; Spottings; Staging; System; Techniques; Technology; Testing; Thick; base; imaging system; indexing; lens; liquid crystal; millisecond; neuronal circuitry; performance tests; response; transmission process; two-photon; vibration

Project summary The fast millisecond timescale of neuronal activity has posed a difficulty for 3D volumetric imaging, whose speed is limited in part by the axial scan methods currently available. The use of electrically tunable lenses (ETLs) for remote focusing confers speed and vibration-reduction advantages over the more traditional sample stage or microscope objective motion, but current state-of-the-art ETLs are liquid lenses that still require mechanical movement from a piezo ring, with their transition speed limited to ~15ms by mechanical ringing. We propose to build and test an ETL based on switchable liquid crystal polarization grating lenses (LCPG lenses) that can perform remote axial focusing at 1ms timescale, an order of magnitude speed improvement over state-of-the-art axial focusing techniques. The LCPG lens is a nonmechanical device and thus has no ringing or hysteresis, particularly useful for repeated scans of the same sample location, or for superresolution techniques where absolute repeatability in axial position is key. The speed of the LCPG lens is not linked to its aperture size, and LCPG lenses can be easily made with 25mm or larger apertures, avoiding vignetting by matching or exceeding the back aperture diameters of modern high-performance objectives. Unlike a piezo- liquid ETL, a LCPG lens can be made with any custom lens profile, including aspherical, and can include compensation for aberrations. Although the LCPG lens offers discrete rather than continuous focal scanning, these devices have >99% efficiency and can be stacked to produce as many focal planes as desired. Using 0.2mm substrates, an 8-stage LCPG lens would be just 4.8mm thick, but could achieve 256 focal planes. The Phase I LCPG lens will have 2 stages and 3 available focal planes, with clear aperture and focal plane location tailored for use as a high-speed remote focusing lens in a two-photon (2P) microscope system. Specific aims: 1. LCPG lens fabrication: Includes fabrication of both LCPG lenses and liquid crystal waveplate switches, assembly into a cascaded stack, index matching, and addition of electrodes. 2. LCPG lens characterization: Includes benchtop characterization of efficiency at the target wavelength, switching speed, and Shack-Hartmann measurement of wavefront quality compared to the template lens. 3. Integration into CW microscope: Using one of our existing CW microscope + 2D spatial light modulator systems, we will characterize the amount of focal length shift introduced by the LCPG lens, along with the 3D focal spot sizes and aberrations in different focal planes. 4. Integration into 2P microscope: We will directly compare the performance of the LCPG lens to the state- of-the-art piezo-liquid lens by replacing a piezo-liquid ETL with the Phase I lens in a 2P microscope system used for 3D neuronal imaging. We will gather feedback from this end user system to focus our further development efforts.

项目摘要 神经元活动的快速毫秒时间尺度对3D体积成像构成了困难 速度部分受到当前可用的轴向扫描方法的限制。使用电镜头 （ETL）对于远程聚焦，赋予速度和振动降低优势比更传统的样本 阶段或显微镜目标运动，但是当前的最新ETL是仍然需要的液态镜头 通过机械振铃，从压电环的机械运动限制为〜15ms。 我们建议基于可切换液晶偏振光镜（LCPG）构建和测试ETL 镜片）可以在1ms时间尺度上执行远程轴向聚焦，这是一个数量级提高的顺序 超过最先进的轴向聚焦技术。 LCPG镜头是一种非机械设备，因此没有 铃声或磁滞，对于重复扫描相同样品位置或超分辨率特别有用 轴向位置绝对可重复性的技术是关键。 LCPG镜头的速度与它的速度无关 孔径尺寸和LCPG镜头可以轻松使用25mm或更大的光圈制成，避免通过 匹配或超过现代高性能目标的后孔直径。与压电不同 液体ETL，可以使用任何定制镜头概况（包括非球形）制作LCPG镜头，并且可以包括 赔偿畸变。尽管LCPG镜头提供离散而不是连续的焦点扫描，但 这些设备的效率> 99％，可以堆叠以产生所需的尽可能多的焦平面。使用 0.2mm的底物，8阶段的LCPG镜头只有4.8mm厚，但可以达到256个焦平面。 I期LCPG镜头将具有2个阶段和3个可用的焦平面，具有清晰的光圈和焦平面 定制的位置是在两光（2p）显微镜系统中用作高速远程聚焦镜头的位置。 具体目的： 1。LCPG镜头制造：包括lcpg镜头和液晶波板开关的制造， 组装成级联的堆栈，索引匹配和添加电极。 2。LCPG镜头表征：包括目标波长处效率的台式表征， 与模板镜头相比，波前质量的开关速度和Shack-Hartmann测量值。 3。集成到CW显微镜：使用我们现有的CW显微镜之一 + 2D空间调制器 系统，我们将表征LCPG镜头引入的焦距转移的量， 3D焦点大小和不同焦距的畸变。 4。整合到2p显微镜中：我们将直接比较LCPG镜头的性能与状态 通过在2p显微镜系统中用I期透镜代替压电式ETL，可以通过压电晶状体的晶状体透镜 用于3D神经元成像。我们将收集此最终用户系统的反馈，以进一步集中 发展工作。