激光共聚焦生物芯片分析仪的二维扫描研究

本文阐述激光共聚焦生物芯片分析仪的组成及特点、CCD和PMT型分析仪的不同,评述了分析仪中的机械式X、Y扫描技术及其不足,着重介绍了光机二维扫描技术的特性、主要参数以及初步实验结果.     

双波长激光共聚焦生物芯片扫描仪的研制

生物芯片扫描仪是生物芯片技术应用中的关键仪器,激光共聚焦成像的原理,着重介绍一种光学扫描和机械扫描相结合的双波长激光共聚焦生物芯片扫描仪,在保证分辨力、灵敏度等重要性能指标的前提下提高了扫描速度和扫描效率,最后对系统性能做了简要分析。     

生物芯片及其荧光信号检测

系统介绍了生物芯片的概念和制造方法,重点讨论了生物芯片的荧光检测方法,并对不同的检测方法进行了对比和分析.总体来说,激光共聚焦芯片扫描仪的荧光检测灵敏度和扫描分辨力较高,而CCD芯片扫描仪的荧光检测灵敏度和扫描分辨力较低,但CCD芯片扫描仪的检测速度较快,成本也较低.     

生物芯片及其荧光信号检测

系统介绍了生物芯片的概念和制造方法 ,重点讨论了生物芯片的荧光检测方法 ,并对不同的检测方法进行了对比和分析。总体来说 ,激光共聚焦芯片扫描仪的荧光检测灵敏度和扫描分辨力较高 ,而 CCD芯片扫描仪的荧光检测灵敏度和扫描分辨力较低 ,但 CCD芯片扫描仪的检测速度较快 ,成本也较低     

生物芯片及其荧光信号检测

系统介绍了生物芯片的概念和制造方法,重点讨论了生物芯片的荧光检测方法,并对不同的检测方法进行了对比和分析.总体来说,激光共聚焦芯片扫描仪的荧光检测灵敏度和扫描分辨力较高,而CCD芯片扫描仪的荧光检测灵敏度和扫描分辨力较低,但CCD芯片扫描仪的检测速度较快,成本也较低.     

线扫描准共焦荧光成像

为了克服目前生物芯片荧光检测方法中诸如系统结构复杂、检测速度慢、灵敏度低、成本高等缺点,提出了一种新型生物芯片荧光检测方法——线扫描准共焦荧光成像法,并搭建了初步原理性装置。用线扫描代替共聚焦中的点扫描,将二维扫描变为一维扫描,在保持高灵敏度的同时,增加了探测速度,简化了系统,降低了成本。为了验证方法的可行性,使用搭建的原理性装置对手工点样的低密度DNA生物芯片进行了荧光成像检测。实验结果显示,系统的空间分辨率18μm,在使用像素平均法降噪后,测量浓度为0.03μmol/l的探针溶液所得信噪比为5.5×102。这项技术综合了面成像检测方法的低成本、结构简单的优势和点共焦方法具有的高分辨率的优点,适合在实验室中对生物芯片进行检测研究。     

双荧光标记生物芯片激光共聚焦检测系统

基于激光共聚焦检测原理,构建了针对荧光标记生物芯片的检测系统,对用Cy₃或Cy₅标记蛋白点样的玻片进行了扫描检测,并对采集的荧光数据信号进行了图像重建。针对实际荧光信号可能较微弱并存在较大动态范围的情况,采用形态学方法对图像进行滤波、增强处理,显著增强了图像质量。提出了标定系统信噪比和灵敏度的公式,并据此对检测实验结果进行了详细的分析计算,最终标定此激光共聚焦生物芯片检测系统的灵敏度约为0.1 fluo/μm²。     

计算生物学研究所筹备会在上海召开

近日由中国科学院电工研究所和光电技术研究所共同承担的中科院知识创新工程重大项目“生物芯片仪器研制”通过专家验收。该项目是具有我国自主知识产权的生物芯片仪器，其中，激光共聚焦生物芯片扫描仪三种、生物芯片点样仪两种、CCD生物芯片检测仪六种。该项目的研究成果目前已实现了产品实用化。     

基于振镜扫描的生物芯片荧光信号光强校正

鉴于传统生物芯片检测装置结构较复杂,共聚焦逐点扫描速度较慢,设计了一种使用激光光源、二维高速振镜和冷却型CCD相结合的新装置,并且建立相应的检测数学模型。新装置以STM32为控制核心,采用弓字型扫描方式采集载玻片上的荧光信号。实验对同一片载玻片上的Cy5荧光染料进行五个不同位置的扫描,并由冷却型CCD曝光采集图片。经实验得到了五个相应位置的灰度图像,通过公式推导建立了检测数学模型并用其进行图像灰度校正,校正后的图像灰度误差在2%以内,可以满足光强一致性的要求。     

激光共焦高速扫描显微成像的高帧速重构算法

针对激光共焦扫描显微镜的往复式逐行扫描成像方式带来的帧图像数据分割难的问题,在分析系统扫描方式、振镜的实际运动方式与理论运动方式差异的基础上,利用相邻两帧图像相似性大的特点,提出了一套完整的高帧速重构算法。该算法通过连续帧特征区域差分的方式实现了一维信号序列的自适应分割,即实现了对一维信号序列进行动态排列及分割成二维阵列图像数据,从而重构出多帧高精度图像。实验表明,该算法的成像误差低于1.6%,适用于成像速度高达300帧/s的激光共焦扫描显微成像。     

激光共焦扫描显微镜的光学特性研究

研究了最新发展的激光头焦扫描显微镜的下述光学特性：分辨本领及像的反差，层析分析原理及三维构像。还给出激光共焦扫描显微镜的基本光学系统及其光路按排。     

A confocal laser microscope scanner for digital recording of optical serial sections

A confocal laser microscope scanner developed at our institute is described. Since an ordinary microscope is used, it is easy to view the specimen prior to scanning. Confocal imaging is obtained by laser spot illumination, and by focusing the reflected or fluorescent light from the specimen onto a pinhole aperture in front of the detector (a photomultiplier tube). Two rotating mirrors are used to scan the laser beam in a raster pattern. The scanner is controlled by a microprocessor which coordinates scanning, data display, and data transfer to a host computer equipped with an array processor. Digital images with up to 1024 × 1024 pixels and 256 grey levels can be recorded. The optical sectioning property of confocal scanning is used to record thin (～ 1 μm) sections of a specimen without the need for mechanical sectioning. By using computer-control to adjust the focus of the microscope, a stack of consecutive sections can be automatically recorded. A computer is then used to display the 3-D structure of the specimen. It is also possible to obtain quantitative information, both geometric and photometric. In addition to confocal laser scanning, it is easy to perform non-confocal laser scanning, or to use conventional microscopic illumination techniques for (non-confocal) scanning. The design has proved reliable and stable, requiring very few adjustments and realignments. Results obtained with this scanner are reported, and some limitations of the technique are discussed.     

A 2D MEMS mirror with sidewall electrodes applied for confocal MACROscope imaging

This paper presents microelectromechanical system micromirrors with sidewall electrodes applied for use as a Confocal MACROscope for biomedical imaging. The MACROscope is a fluorescence and brightfield confocal laser scanning microscope with a very large field of view. In this paper, a microelectromechanical system mirror with sidewall electrodes replaces the galvo-scanner and XYZ-stage to improve the confocal MACROscope design and obtain an image. Two micromirror-based optical configurations are developed and tested to optimize the optical design through scanning angle, field of view and numerical aperture improvement. Meanwhile, the scanning frequency and control waveform of the micromirror are tested. Analysing the scan frequency and waveform becomes a key factor to optimize the micromirror-based confocal MACROscope. When the micromirror is integrated into the MACROscope and works at 40 Hz, the micromirror with open-loop control possesses good repeatability, so that the synchronization among the scanner, XYZ-stage and image acquisition can be realized. A laser scanning microscope system based on the micromirror with 2 μm width torsion bars was built and a 2D image was obtained as well. This work forms the experimental basis for building a practical confocal MACROscope.     

数字X线影像仪中激光扫描光学系统的设计

数字X线影像仪是计算机和激光技术快速发展的产物,而其中的激光扫描光学系统是其核心技术之一。针对数字X光影像仪的使用特点,对激光扫描系统中的Fθ镜头、光束扩展器、扫描器这几个关键部件进行了较详细的论述分析,提出并解决了其中一些关键问题,如光阑位置浮动对像质的影响、影响系统扫描光点大小的因素、扫描器的确定等。最后用ZEMAX光学设计软件对系统的光学性能进行了设计模拟,得到扫描光斑直径小于0.1mm、焦距和视场满足线性关系的设计结果。像质评价分析结果表明,所设计的镜头像质优良,轴上与轴外质量相当,像质达到衍射极限。     

Inexpensive, high-quality optical relay for use in confocal scanning beam imaging

An inexpensive, high optical-quality relay lens made up of two eyepieces arranged in an afocal assembly for use in confocal scanning laser imaging is described. In the past we have used relays, within our confocal microscopes, made up of achromats with long focal lengths (> or = 10 cm), which take up large optical tracks and suffer from significant amounts of astigmatism and curvature of field. We quantify aberrations associated with achromat and eyepiece relays using CODE V optical design and analysis software. The eyepiece relay is found to be more compact, better corrected, and not significantly more expensive than its achromat counterpart. In addition to being used to interconnect two scanning mirrors optically as well as scanning mirrors with microscope objectives, it can form part of the optics in a confocal scanning laser MACROscope-Microscope system (Biomedical Photometrics, Inc., Waterloo, Ontario, Canada). Due to design constraints, the MACROscope-Microscope system cannot incorporate a conventional wide-field microscope into its structure such as is done in most commercial confocal microscopes. The eyepiece relay is used as a stand-alone, compact optical link between the scanning mirrors and the microscope objective. This consequently makes the MACROscope-Microscope system more compact and easier to commercialize.     

基于磁悬浮式基因生物成像扫描仪电磁结构设计

针对常规基因生物芯片成像系统由于基因芯片位姿调整频繁而引起的调整机构机械磨损的关键问题,设计一种基于磁悬浮的基因生物芯片成像扫描仪。根据基因生物芯片成像扫描仪的工作原理及磁悬浮技术的结构特点,建立由电磁参数与成像分辨率组成的系统微分阵列,通过理论优化确定电磁结构参数,采用有限元分析法对系统进行电磁热结构耦合分析,优化分析结果并搭建实验测试装置。利用本装置对基因生物芯片成像扫描仪进行参数标定,验证扫描仪磁悬浮系统结构设计结果,并与进口PCR仪进行实验测试数据比对。结果表明,本文设计的磁悬浮式基因生物成像扫描仪电磁结构匝数为340 N时产生的有效电磁面积为180 mm~2,此时磁悬浮系统精度误差小于0.15 mm,与仿真数据基本吻合,与美国Bio-Rad数字PCR系统做T790M突变检测的数据对比实验所测得结果CV<5%。本文设计的基于磁悬浮的基因生物芯片成像扫描仪精度可以满足基因生物芯片成像检测的要求,为提升调整装置使用寿命方面提供核心技术保障,在提升临床肿瘤筛查、基因诊断技术中发挥重要的作用。     

共聚焦激光扫描荧光显微镜扫描系统研制

为适应三维光学微细加工及三维光学信息存储研究的需要,研制了共聚焦激光扫描荧光显微镜的工作台式扫描系统,扫描范围138μm×138μm.工作台采用压电陶瓷驱动器( PZT actuator)驱动的方式来获得高分辨率的位移,采用带柔性铰链的杠杆放大装置来获得较大的位移范围.描述了工作台的工作原理,并对其静态和动态性能进行了测试,实验表明这一扫描系统能很好的应用于共聚焦激光扫描荧光显微镜系统.     

Large angle and high linearity two-dimensional laser scanner based on voice coil actuators

A large angle and high linearity two-dimensional laser scanner with an in-house ingenious deflection angle detecting system is developed based on voice coil actuators direct driving mechanism. The specially designed voice coil actuators make the steering mirror moving at a sufficiently large angle. Frequency sweep method based on virtual instruments is employed to achieve the natural frequency of the laser scanner. The response shows that the performance of the laser scanner is limited by the mechanical resonances. The closed-loop controller based on mathematical model is used to reduce the oscillation of the laser scanner at resonance frequency. To design a qualified controller, the model of the laser scanner is set up. The transfer function of the model is identified with MATLAB according to the tested data. After introducing of the controller, the nonlinearity decreases from 13.75% to 2.67% at 50 Hz. The laser scanner also has other advantages such as large deflection mirror, small mechanical structure, and high scanning speed.