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微型差动式共焦自聚焦光聚焦探测系统 总被引:1,自引:0,他引:1
为解决微小内轮廓尺寸为代表的微小尺寸的非接触式超精密测量问题,提出了将自聚焦透镜体积小的特点与共焦显微技术的高分辨率和绝对位置跟踪特性相结合的差动式自聚焦共焦微型显微技术的光探测技术,建立了相应的传感系统,介绍了系统的工作原理和构成,自聚焦透镜测头直径为1mm,两个探测器差动设置,不但消除了光源的光强漂移和探测器的电子漂移产生的共模噪声,提高了测量信噪比,而且有效地提高了系统的轴向分辨率,初步实验表明,系统轴向分辨率在倾斜率小于20度的范围内可达5nm。 相似文献
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In order to improve the spatial resolution of a confocal system, a radial birefringent pupil filter (RBPF) is introduced into a differential confocal system. RBPF consists of two polarizers with a birefringent element between them, and its pupil function is deduced from Jones matrix. The thickness and curvature radius of RBPF are optimized independently, using the first zero coordinate ratio. The pupil function is modulated by RBPF to enhance the half-width of the response function, and lateral resolution is improved when response curve is changed with the position of RBPF as well as the polarization; then axial super-resolution of the system can be guaranteed using differential confocal detection mechanism. In comparison with conventional pupil filtering technology, RBPF features high lateral resolution and can be easily produced; moreover, it also has a simple structure. Together with its low cost, RBPF provides a new way for the improvement of super-resolution of confocal system. It is indicated from theoretical analysis and preliminary experiments that the lateral resolution can be significantly improved and the measurement error is reduced by 76 nm when measuring a standard grating of period 3 μm; the axial resolution up to 3 nm has been achieved using the optimized pupil filter. In addition to its application for measurement of a small irregular surface in a limited space, the whole differential confocal system proposed can be fitted onto a coordinate measuring machine for non-contact measurement of dimensions and surface roughness. 相似文献
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差动共焦式纳米级光聚焦探测系统的研究 总被引:5,自引:0,他引:5
为解决纳米级大范围的非接触测量问题 ,提出了基于差动式共焦显微技术的光聚焦探测系统。介绍了系统的工作原理和结构装置 ,对系统中的关键技术进行了优化设计 ,通过对共焦光路的差动设计 ,可以有效地抑制光源的噪声和漂移对测量结果的影响。初步实验结果表明 ,该系统的轴向分辨率可达 2 nm 相似文献
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提出一种新的具有高空间分辨力的整形环形光式差动共焦测量方法。该方法通过整形环形光式共焦测量法和锐化爱里斑主瓣,改善系统横向分辨力;通过差动共焦测量法改善系统的轴向分辨力,最终达到提高系统空间分辨能力的目的。理论分析和实验表明:整形环形光内孔归一化半径ε越大,横向分辨力改善越明显,量程扩展范围越宽;当入射光波长λ=632.8nm,物镜数值孔径取NA=0.85,ε=0.5时,该系统的横向分辨力优于0.2μm,轴向分辨力优于2nm。该方法为光触针测量系统空间分辨力的提高提供了1种新的方法,可广泛应用于超精密三维微细结构工件的超精密测量。 相似文献
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In order to achieve a higher lateral resolution required for ultraprecision measurement of microstructural workpieces, phase-only pupil filtering differential confocal microscopy (PFDCM), a new approach is proposed based on the differential confocal microscopy (DCM), which uses a three-zone phase-only pupil filter with lateral super-resolution capability obtained through optimized design to change the distribution of DCM three-dimensional point spread function, so that the DCM lateral resolution is therefore significantly improved while its axial resolution is slightly improved. Preliminary experimental comparison and analyses indicate that, the lateral and axial resolutions of PFDCM are better than 0.2 μm and 2 nm, respectively, when wavelength of incidence laser beam , numerical aperture of measuring lens NA=0.85, and lateral spot size with a three-zone phase-only pupil filter GT=0.65. It is therefore concluded that PFDCM is a new approach to further improvement of lateral resolution in laser probe measurement systems. 相似文献
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光谱共焦三维形貌仪具有精度高、测量范围大、适应性强等特点,其关键部件是产生轴向色散的物镜,色散物镜轴向色散与波长间的非线性会导致系统整体性能下降。分析了共焦法检测表面形貌的工作原理,以及产生线性轴向色散的条件,根据共焦光学系统的基本设计原理,在预设的设计指标及要求下,完成一个超大色散线性物镜组设计。该色散物镜组采用四级串联结构,在400~700 nm光谱范围内达到30 mm的色散范围,波长离焦量和波长之间线性度通过线性回归拟合得出判定系数为1,满足色散的线性度要求。 相似文献
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We discover that the slight transverse offset of a point detector results in a shift of the axial intensity response curve in a dual-axes confocal microscopy (DCM). Based on this, we propose a new dual-axes differential confocal microscopy (DDCM) with high axial resolution and long working distance, in which two point detectors are placed symmetrically about the collection axis. And a signal is obtained through the differential subtraction of two signals received simultaneously by the two point detectors. Theoretical analyses and preliminary experiments indicate that DDCM is feasible and suitable for the high precision tracing measurement of microstructures and surface contours. 相似文献
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应用共焦显微镜原理测量倾斜工程表面 总被引:3,自引:3,他引:0
用基尔霍夫衍射公式分析反射式共焦光路 ,得到了被测件有一定倾斜角度表面的共焦轴向响应理论模型。由菲涅耳衍射近似公式得到的共焦轴向响应特性只是它的理论模型的一个特例。同时 ,对接收端采用差动连接的共焦测量的聚焦瞄准信号进行了分析 ,得到了表面倾斜角对聚焦瞄准信号影响的关系。应用共焦实验系统及差动测量系统对具有不同倾角的块规斜面的轴向响应信号进行了测量。理论模型的数值分析与实验结果相吻合。用差动共焦光学系统作为瞄准传感器、用电容传感器进行位移监测 ,对倾角为 10°的角规的斜面进行测量 ,得到分辨率小于 2 0nm的表面形貌图。 相似文献
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基于共焦原理的反射式自聚焦光纤传感技术研究 总被引:2,自引:2,他引:0
基于共焦显微成象原理,提出了一种由自聚焦透镜和X型光纤组成的高精度反射式自聚焦光纤传感器.该传感器具有绝对位置跟踪的特殊能力,并有体积小、抗干扰性强、轴向分辨率高等特点.由实验分析得,其轴向分辨率可达30nm.可用于表面微观形貌、外形尺寸、曲面轮廓等测量领域. 相似文献
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激光差动共焦显微镜具备高空间分辨率特点,但因其逐点扫描成像方式,扫描时间长,易受三维扫描系统不稳定和环境干扰等影响,产生系统漂移,影响仪器的空间分辨率。利用楔块机构高稳定特点,结合刹车机构的自由抱闸特性,设计了一种新型的轴向升降机构,由此构建了结构更具稳定特性的电动三维扫描系统。稳定性实验验证在搭建的激光差动共焦显微镜上进行,经过监测系统在90min内的轴向位置,轴向漂移小于50nm,与原三维扫描系统漂移140nm对比,漂移速度明显减慢,稳定性有显著提升,进而明显改善了差动共焦显微成像效果。 相似文献
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A major obstacle in the race to develop two-photon fluorescence endoscopy is the use of complicated bulk optics to transmit an ultrashort-pulsed laser beam and return the emitted fluorescence signal. We describe an all-fiber two-photon fluorescence microendoscope based on a single-mode optical fiber coupler, a microprism, and a gradient-index rod lens. It is found that the new endoscope exhibits an axial resolution of 3.2 microm and is capable of imaging transverse cross sections of internal cylindrical structures as small as approximately 3.0 mm in diameter. This device demonstrates the potential for developing a real-time diagnostic tool for biomedical research without the need for surgical biopsy and may find applications in photodynamic therapy, microsurgery, and early cancer detection. 相似文献
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Use of an aspherical surface in the design of a lens system for one-to-many optical-interconnects (OTM-OI), composed of a doublet lens and a gradient-index (GRIN) lens array has been investigated. Applying the procedure of ALSIE (Automatic Lens design by Solving InEqualities), the off-axis lens systems, which feature the optical performance of the OTM-OI lens system, are optimized at 0.1 numerical aperture with a total field of view of 2°. Three aspherical designs with the aspherical surface for different surfaces are presented. The aspherical designs show preferable modulation transfer function (MTF) for high frequency as compared with the spherical design. 相似文献
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For the first time, to the best of authors’ knowledge, a no-moving-parts axial scanning confocal microscope (ASCM) system is designed and demonstrated using a combination of a large diameter liquid crystal (LC) lens and a classical microscope objective lens. By electrically controlling the 5 mm diameter LC lens, the 633 nm wavelength focal spot is moved continuously over a 48 μm range with a measured 3-dB axial resolution of 3.1 μm using a 0.65 numerical aperture (NA) micro-objective lens. The ASCM is successfully used to image an Indium Phosphide (InP) twin square optical waveguide sample with a 10.2 μm waveguide pitch and 2.3 μm height and width. Using fine analog electrical control of the LC lens, a super-fine sub-wavelength axial resolution of 270 nm is demonstrated. The proposed ASCM can be useful in various precision three-dimensional (3D) imaging and profiling applications. 相似文献
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轴对称矢量光束是一种空间非均匀偏振光束, 中心光强为零, 经物镜聚焦后能在焦点附近产生空间场分量. 在高变迹系数光学系统成像情况下, 与线偏光、圆偏光相比, 径向偏振光与光瞳滤波技术及图像复原技术结合, 能获得较小焦斑, 提高横向分辨力. 介绍了轴对称矢量光束的特性, 基于电偶极子辐射模型和矢量衍射理论研究了轴对称矢量光束经高数值孔径物镜聚焦后的特性, 系统介绍了基于轴对称矢量光束实现光斑紧聚焦的几种方法, 并简述了轴对称矢量光束在差动共焦超分辨成像领域的研究设想.
关键词:
差动共焦显微技术
紧聚焦
光瞳滤波
轴对称矢量光束 相似文献