共查询到19条相似文献,搜索用时 375 毫秒
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为了定标测量系统、提高测量精度,在简要论述了激光球面干涉仪的原理以后,采用移相技术,获得了四幅干涉图,并提取出范围在[-π,π)之间的相位。然后,利用相位消跳变算法,展开得到连续的相位。最后经过消倾斜和离焦等后继处理,得到了系统的波面误差。 相似文献
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共光路径向剪切干涉仪的设计 总被引:2,自引:2,他引:0
针对常规像移式干涉仪无法用于大口径、长光路光学系统波像差检测的工程问题,设计了共光路径向剪切干涉仪以消除采用标准波面所引入的系统误差.设计中采用由三角棱镜与斜方棱镜组合而成的胶合棱镜组作为波面剪切器件,将待测波面与其复制波面产生干涉,并通过一组有不同相对孔径的透镜切换装置来控制干涉仪剪切比.与4D动态干涉仪在不同条件下... 相似文献
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环境振动和半导体激光器输出扰动都会引起移相干涉仪(PSI)光学干涉场变化,为了评估环境振动对PSI的影响,在干涉仪内部,用两只光电管分别测量光学干涉场某点辐射功率的变化及半导体激光器输出功率的扰动,可析取移相干涉仪的环境振动信息。两路光电测量信号经单片机进行模数转换后由串行通信接口传输到PC机,通过可视化软件编程技术实现信号的图形化显示和环境振动信息的析取。 相似文献
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曲率半径的高精度测量及其不确定度 总被引:1,自引:0,他引:1
为了高精度测量光学元件的曲率半径,提出了一种利用反射式计算全息元件结合波长移相干涉测长技术测量光学球面曲率半径的方法.测试中,将反射式计算全息元件作为基准来标定所用标准镜头参考面的曲率半径,利用波长移相干涉技术测量干涉腔腔长,通过计算分析得到被测元件的曲率半径.文中描述了该方法的系统构成及其工作原理.结合实例,运用理论分析与软件仿真模拟分析了方法的测量不确定度.最后,利用实验室现有的商用波长移相干涉仪进行了实验验证.对一口径为100 mm的球面样品进行曲率半径的测量,得到的结果为157.108 3 mm;利用接触式球径仪法对同一样品进行对比测量,结果显示相对误差小于0.02%.与其它目前已有的非接触式曲率半径测量方法相比,提出的方法具有误差源少、测量精度高、易于操作等优点. 相似文献
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步进电机作为执行元件,是实现机电一体化的关键产品之一,在工业自动化中有着广泛的应用。但在某些特殊应用场合,被控步进电机数量相对比较多,并且需要进行切换控制,在切换过程中,传统控制方式下步进电机存在一个相位错位的问题,这在一定程度上影响了控制的精度。文中提出了一种引入相位反馈来消除这种相位错位的方法,此方法在实际工程应用中取得了很好的效果。 相似文献
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Quantitative optical microscope with enhanced resolution using a pixelated liquid crystal spatial light modulator 总被引:1,自引:0,他引:1
This paper presents a brief account of a novel optical microscope, which combines the advantages of two well‐known techniques, namely phase contrast and phase stepping, to provide high contrast imaging and precision measurements. The inclusion of a programmable liquid crystal spatial light modulator provides for the phase stepping required, while also allowing flexibility for future improvements. The results shown reveal an important aspect of the system to facilitate quantitative sample measurements, with an enhancement of optical resolution compared with conventional optical imaging systems. 相似文献
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相移器平移误差与倾斜误差不敏感相移新算法 总被引:1,自引:1,他引:0
相移器的相移误差包括平移误差与倾斜误差,使同一幅干涉图诸像素点的相移量并不相等,但仍然在同一平面上.据此,本文提出了消除相移器位移误差与倾斜误差的最小二乘迭代算法.通过对相移平面的最小二乘拟合,即可以消除相移器平移误差与倾斜误差对位相分布求解结果的影响.并通过数值模拟,验证了这种算法在消除相移器位移误差与倾斜影响上的有效性. 相似文献
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为了实现大范围的水下微弱声波探测,提出了一种基于后向瑞利散射空间差分干涉的光纤分布式声波检测(DAS)技术。声波振动引起单模传感光纤中后向瑞利散射光的变化,将含有声波信息的后向瑞利散射光注入到非平衡迈克尔逊干涉仪,调节干涉仪的臂长差实现不同长度的相邻空间段的后向瑞利散射光干涉,然后采用3×3耦合器解调技术解调出相位信息,实现声波信号的测量。实验搭建了一套基于DAS技术的水下声波测量系统,该系统不仅能够实时准确定位两个声波位置,还能还原声波的幅值、频率、相位等信息,并且实现了1kHz情况下的-148.8dB(re rad/μPa)水下声压相位灵敏度,100~1 500Hz频率的频响平坦度在1.2dB之内。实验结果证实DAS技术能够实时快速地实现多个声波信息的定量测量。 相似文献
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Measurement of specimen-induced aberrations of biological samples using phase stepping interferometry 总被引:1,自引:0,他引:1
Confocal or multiphoton microscopes, which deliver optical sections and three‐dimensional (3D) images of thick specimens, are widely used in biology. These techniques, however, are sensitive to aberrations that may originate from the refractive index structure of the specimen itself. The aberrations cause reduced signal intensity and the 3D resolution of the instrument is compromised. It has been suggested to correct for aberrations in confocal microscopes using adaptive optics. In order to define the design specifications for such adaptive optics systems, one has to know the amount of aberrations present for typical applications such as with biological samples. We have built a phase stepping interferometer microscope that directly measures the aberration of the wavefront. The modal content of the wavefront is extracted by employing Zernike mode decomposition. Results for typical biological specimens are presented. It was found for all samples investigated that higher order Zernike modes give only a small contribution to the overall aberration. Therefore, these higher order modes can be neglected in future adaptive optics sensing and correction schemes implemented into confocal or multiphoton microscopes, leading to more efficient designs. 相似文献
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The ability to image phase distributions with high spatial resolution is a key capability of microscopy systems. Consequently, the development and use of phase microscopy has been an important aspect of microscopy research and development. Most phase microscopy is based on a form of interference. Some phase imaging techniques, such as differential interference microscopy or phase microscopy, have a low coherence requirement, which enables high‐resolution imaging but in effect prevents the acquisition of quantitative phase information. These techniques are therefore used mainly for phase visualization. On the other hand, interference microscopy and holography are able to yield quantitative phase measurements but cannot offer the highest resolution. A new approach to phase microscopy, quantitative phase‐amplitude microscopy (QPAM) has recently been proposed that relies on observing the manner in which intensity images change with small defocuses and using these intensity changes to recover the phase. The method is easily understood when an object is thin, meaning its thickness is much less than the depth of field of the imaging system. However, in practice, objects will not often be thin, leading to the question of what precisely is being measured when QPAM is applied to a thick object. The optical transfer function formalism previously developed uses three‐dimensional (3D) optical transfer functions under the Born approximation. In this paper we use the 3D optical transfer function approach of Streibl not for the analysis of 3D imaging methods, such as tomography, but rather for the problem of analysing 2D phase images of thick objects. We go on to test the theoretical predictions experimentally. The two are found to be in excellent agreement and we show that the 3D imaging properties of QPAM can be reliably predicted using the optical transfer function formalism. 相似文献
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基于斜入射的平面度绝对检验方法 总被引:1,自引:0,他引:1
为了获得高反射率光学平面的绝对面形分布,提出了基于斜入射的平面度绝对检验方案.该方法通过菲索干涉仪的空腔干涉以及两次斜入射测量得到三组波面数据,使用Zemike多项式对波面拟合,通过求解待测表面的旋转不变量和旋转因变量获得整个平面的绝对面形分布.测量90 mm口径的镀铝反射镜,其绝对检验结果为0.266λ(PV),0.075λ(RMS).讨论了测试中斜入射角及旋转角的选取方法,并分别选择45°和54°进行测试.基于斜入射的平面度绝对检验方法操作步骤简单,特别适合于高反射率光学表面的绝对面形检测. 相似文献
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用四个法布里——珀罗标准具实现的机载激光报警装置 总被引:3,自引:0,他引:3
本文介绍了一种应用四个阶式法布里——珀罗(F-P)标准具实现的机载全方位激光报警装置。该装置由光学探测系统、信号放大与处理系统和显示报警系统三部分组成。光学探测系统主要包括:阶式F-P标准具、聚焦透镜、PIN光电二极管、步进电机及单片机等;信号放大与处理系统主要包括:信号放大电路、模—数转换电路、高速单片机及火控计算机等;显示报警系统则主要由声告警器、显示器及相应的存储电路等构成。文中还详细介绍了该装置的基本原理、结构及主要技术指标,讨论了其中的技术难点及相应的解决方案。 相似文献