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1.
根据干涉图样条纹的变化来调节仪器,简单快捷;巧妙使用透镜,观察方便,记数准确。  相似文献   

2.
白光干涉实验方法探讨   总被引:2,自引:0,他引:2  
分析迈克尔逊干涉图样的特点以及白光干涉条件,探讨白光干涉的调节方法。  相似文献   

3.
通过分析杨氏双缝干涉明暗条纹理论公式所采用的形式与干涉图样级数常规定义的不符,对公式形式加以修正.  相似文献   

4.
从三个实验现象出发,详细讨论了三个实验图样的特点,明暗纹分布规律以及定量计算公式的推导,并对这三部分的教学顺序提出了建议.  相似文献   

5.
激光诱导等离子体干涉图相位信息的提取   总被引:1,自引:0,他引:1  
陈汝钧 Jin  YH 《光学学报》1995,15(12):697-1701
分析了强激光在空气中产生等离子体干涉图的空间频谱特性,采用高阶契比雪夫数字递归滤波器和阈值自动调整的相位解包算法成功地撮了等离子体干涉图的相位信息。论述了对干涉图样进行数字滤波时的设计考虑,给出了实验结果。实验表明,这种方法可用于快速、瞬态光学干涉图样相位信息的提取。  相似文献   

6.
为实现高精度大量程精密位移测量,提出了一种基于涡旋光共轭干涉的精密位移测量方法。通过建立位移过程中涡旋光共轭干涉图样的旋转角弧度与位移之间的数学关系,实现了对旋转角弧度的精确提取,得到了高精度的精密位移测量结果。基于该原理对测量方案进行了光学系统设计与仿真,研制了实验系统并进行了实验测试。当标准位移为20 nm时,实验测量结果的误差为25 pm,相对误差为0.13%,证明了所提亚纳米级精密位移测量方案的有效性。所提系统还可通过计量干涉图样旋转圈数进行大测量范围的精密位移测量。实验结果表明,所提方案可在30μm范围内实现精密位移测量。  相似文献   

7.
迈克尔逊干涉仪的非定域干涉图样通常是明暗相间的同心圆环.点光源产生的非定域干涉,如图1.激光束通过短焦距透镜会聚成一强度很高的点光源.S,S发出的球面波经分光板G1及经平面镜M1和M2反射,  相似文献   

8.
两圆偏振光以及线偏振光和圆偏振光干涉图样的衬比度   总被引:1,自引:1,他引:0  
蔡履中 《大学物理》2004,23(1):16-18
考察了两束圆偏振光之间以及线偏振光与圆偏振光之间干涉所形成图样的衬比度,并与两束线偏振光之间干涉图样的衬比度进行了比较.指出在非共面多光束干涉中有可能利用圆偏振光以改善干涉图样的整体衬比度,并简要介绍了它在光子晶体制备中的应用.  相似文献   

9.
关荣华 《工科物理》1998,8(5):43-44
通过分析杨氏双缝干涉明暗条纹理论公式所采用的形式与干涉图样级数常规定义的不符,对公式形式加以修正。  相似文献   

10.
刘金江  唐恩辉 《物理实验》1989,9(3):104-105
本文提出了观察洛埃镜实验中出现的半波拟失的一种方法,即利用杨氏双缝产生的干涉图样与洛埃镜产生的干涉图样直接实时对比,来观察洛埃镜实验中出现的半波损失现象。现象明显直观,方法简单易行。  相似文献   

11.
Yin L  Wang Q  Zhang Q  Jiang H 《Optics letters》2007,32(17):2556-2558
We present a new method that can provide high resolution images of absolute optical absorption coefficient in heterogeneous turbid media. In this method, acoustic measurements in conventional photoacoustic tomography are combined with diffusing light measurements to separate the product of absorption coefficient and optical fluence or photon density. We validate this method using a series of tissuelike phantom experiments. The experimental results show that targets as small as 0.5 mm in diameter with optical absorption contrasts as low as 1.5 relative to a 50 mm diameter scattering background medium can be clearly detected.  相似文献   

12.
The diameter of cylindrical openings is conventionally measured with the mechanical and contact method. In this paper, we propose a contactless optical approach to measure dimensions of inner profile by a disk beam probe. The measurement is carried out illuminating the inner cylindrical opening with a light sheet generated by the disk beam probe, acquiring the light-section image of the object with an image sensor through a widefield lens, then numerically extracting the diameter. During measurement, the probe is aligned inside the openings with high freedom, which causes the optical section to manifest a variety of ellipses besides a circle accordingly. The measurement method copes with extracting the diameter of openings from various ellipse optical sections. The high freedom of probe alignment allows optical diameter measurement to be flexible and simple. The dimensions of cylindrical openings of manufactured parts were practically measured with the disk beam probe, and the results were confirmed with those measured with the vernier caliper.  相似文献   

13.
The Mie Scattering Imaging method (MSI) gathers out‐of‐focus images of dispersed spherical particles present in a laser light sheet and extracts the individual particle diameter from these images. The general idea of the method has been around for more than a decade and a number of papers has dealt with it over recent years. Our work focuses on small particle sizes from 20 μm down to 2 μm, a range which has not been tackled so far although it is of great importance in particle systems. We present an optical set‐up with a special arrangement of camera lenses that allows to work in this range. An evaluation algorithm based on correlation of the experimental optical information with theoretical Mie scattering was found to give the most accurate results for particle sizing. Besides accuracy measurements on solid spheres the versatility of the method is demonstrated by an example of transient droplet growth between 2–7 μm.  相似文献   

14.
为提升线结构光传感器的标定效率与精度,设计了一种集成自背光可调节位姿的平面棋盘格-同心圆互补线结构光标定系统。该系统基于同心圆圆心的真实投影位置与投影椭圆圆心位置的几何关系,建立非线性优化偏心误差补偿模型,精确得到透射投影下圆心偏心误差补偿位置。该方法与传统标定方法对比降低重投影误差84.7%,有效解决了圆形标志物偏心误差补偿的高精度标定难题。通过将相机坐标系下过光心、光条中心线的平面与靶标平面结合,多次获取空间交线的坐标信息增加特征点,并使用最小二乘法拟合光平面方程,解决了因特征点少从而平面拟合标定精度较低的问题。在复杂环境下重复实验测得大尺寸砂轮外径误差均值为0.005 1 mm,结果表明该标定系统具有一定的准确性和简便实用性。  相似文献   

15.
Xu J  Zhang XC 《Optics letters》2004,29(17):2082-2084
We report the design and testing of a circular involute stage for high-repetition-rate (hundreds of hertz), fine temporal resolution (better than 10 fs), and long delay range (as great as nanoseconds) time-resolved optical experiments. This stage uses a reflector with the involute profile of a circle as well as a pair of optical mirrors mounted upon a rotating plate to guide the optical beam, following the tangent of the circle. This circular involute stage provides unprecedented performance for optical interference, high-resolution terahertz time-domain spectroscopy, and general optical pump-probe experiments.  相似文献   

16.
A brief review of the existing particle sizing methods is presented. An optical method under development is introduced from the analysis of the polarization ratio of the light scattered by the particles based on Lorenz-Mie theory. The theoretical background is summarized with the numerical calculation presented. A photogrammteric system has been set up to perform the measurements. Calibration of the experimental setup has been carried out on polystyrene microspheres of different size. The experimental values of the polarization ratio have been obtained by analyzing the particle images taken by the CCD to render the particle size under investigation. Several experiments and their results are demonstrated to illustrate the application fields of the optical method presented in the current study.  相似文献   

17.
We proposed a novel method for fabricating polymer compound microlenses (PCMLs) using micro-inkjet technique and subsequent curing process. Two different types of PCMLs with sandwich microstructure (PDMS-Glycerol-PDMS), concave and convex PCMLs, have been designed and fabricated in experiments. Convex PCML has two real images and two foci. The concave PCML has one real and one virtual focal planes, which can generate one real image and one virtual image respectively. Moreover, the diameter of concave PCML can be controlled by adjusting the curing time and temperature. The proposed method is simple, efficient and suitable for realizing large-scale high numerical aperture PCMLs array, which has potential applications in diverse optical systems such as optical storage and three-dimensional imaging.  相似文献   

18.
一种快速检测圆心的抗噪声亚像素算法   总被引:16,自引:4,他引:12  
侯成刚  杨文献 《光学学报》1998,18(4):81-485
在印刷电路板的自动光学检测中,被检对象的空间对准是一个关键步骤,而传统的图像匹配技术由于其只能在像素级定位,而无法适应印刷电路板精确对准的要求。本文利用圆的几何对称性,提出一种在亚像素精度快速定位圆心的算法。  相似文献   

19.
Improving the accuracy of circle detection in images is important for feature detection in remote sensing imagery. The standard Hough transform detects circles from the whole image space, which inclines to be disturbed by noise and the imperfection of the edge information. In this paper, a method of voting and determining circles locally is proposed. This method improves the accuracy and stability of circle detection in images with noise, incomplete edge information and complex backgrounds. Synthetic and real satellite images are used to demonstrate the effectivity of circle detection of the proposed method.  相似文献   

20.
光学相干层析图像层状结构的增强与定量测量   总被引:3,自引:0,他引:3  
光学相干层析(OCT)成像技术对于眼底等层状组织的定量测量有赖于光学相干层析图像中层状结构的提取。为了对原始光学相干层析图像进行预处理以有效地去除图像中的噪声及散斑、增强图中的层状结构,并更好地保护图像中的层状结构,进而更准确地定量测量图像中有重要意义的层状结构的光程信息,提出在相干增强各向异性扩散(CED)算法中引入二阶导数项以控制沿相干方向的扩散强度,并将引入二阶导数项的相干增强各向异性扩散算法应用于不同样品的光学相干层析图像。结合在预处理后图像中层状结构位置的查找结果与样品的折射率信息,实现了对光学相干层析图像中有重要意义的层状结构厚度的定量测量。实验结果表明,使用引入二阶导数项的相干增强各向异性扩散算法对光学相干层析图像预处理有利于对图中重要层状结构的更准确测量。  相似文献   

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