SBIR Phase I: High-power laser compatible MEMS deformable mirrors for confocal and two-photon microscopy

这个小型企业创新研究第一阶段项目将通过使用静电驱动的可变形薄膜反射镜(DMM)，在双光子显微镜(TPM)内实现视频率三维(3D)成像。作为激光扫描显微镜(LSM)的一个子集，TPM利用聚焦的高功率激光束同时吸收两个低能量的红外光子来激发荧光，从而在可见光范围内激发发射，从而实现非常高的空间分辨率。由于与其他LSM方法相比，TPMS的分辨率更高，红外线对组织的渗透率更高，因此在医疗行业中已被广泛接受，特别是在皮肤科和神经科。为该项目开发的技术将面向5亿美元的LSM市场，提供一种低成本、电可调的光学器件，能够同时控制聚焦和像差，同时运行速度比竞争对手的技术快一个数量级。这项技术实现的3D成像能力将导致显微镜技术和诊断方法的进步，从而减少诊断时间和患者的不适感。其他可以通过这项技术轻松解决的市场包括激光标记和雕刻、内窥镜、光学相干断层扫描和机器视觉。该项目的智能价值将是开发用于基于微电子机械系统(MEMS)的可变形反射镜的高功率涂层。由于这些反射镜由一层带有反射面的薄膜组成，因此标准的固体基板玻璃镀膜工艺是不兼容的。相反，反射镜的表面材料必须在DMM的许多制造步骤中的一个步骤内沉积。该项目将解决开发高反射涂层的独特挑战，并将其纳入现有的DMM制造工艺。该项目涉及四个关键目标：1)开发镀金可变形反射镜，2)开发受保护的镀银可变形反射镜，3)测量关键性能参数，4)测量和确定金和银数字万能表的功率处理能力和损伤阈值。预期的结果将是一种完全表征的数字万用表，能够在双光子显微镜中使用的高功率飞秒激光照明条件下长期工作。

This Small Business Innovation Research Phase I project will enable video-rate three-dimensional (3D) imaging within two-photon microscopes (TPMs) through the use of an electrostatically actuated deformable membrane mirror (DMM). As a subset of laser scanning microscopes (LSMs), TPMs achieve very high spatial resolution by using a focused, high-power laser beam to excite fluorescence via the simultaneous absorption of two low energy infrared photons to stimulate emission in the visible. Because of the increased resolution, and increased penetration of infrared light into tissue compared with other LSM methods, TPMs have become widely accepted for use in the medical industry, specifically for dermatology and neurology. The technology developed for this project will address the $500 million LSM market by delivering a low-cost, electrically tunable optic capable of simultaneously controlling focus and aberrations while operating an order of magnitude faster than competitive technologies. The 3D imaging capabilities enabled by this technology will result in an advancement of microscopy techniques and diagnostic methods, thereby reducing diagnostic time and patient discomfort. Other markets that can easily be addressed by this technology include laser marking and engraving, endoscopes, optical coherence tomography, and machine vision. The intellectual merit of this project will be the development of high-power capable coatings for micro-electro-mechanical systems (MEMS) based deformable mirrors. Because these mirrors consist of a thin membrane with a reflective surface, standard glass coating processes for solid substrates are incompatible. Instead, the surface material for the mirror must be deposited within one of the many fabrication steps for the DMM. This project will address the unique challenges of developing high-reflectance coatings and incorporate them into the existing DMM fabrication process. The project involves four key objectives: 1) developing gold coated deformable mirrors, 2) developing protected silver coated deformable mirrors, 3) measuring key performance parameters, and 4) measuring and defining the power handling capability and damage thresholds of gold and silver DMMs. The anticipated result will be a fully characterized DMM capable of long operation under the high-power femtosecond laser illumination regime used in two photon microscopes.