大气激光光斑图像处理技术研究

激光大气中传输时由于折射率梯度和湍流效应造成激光光斑重心的弯曲和漂移,通过对外场光斑的分析处理来是研究激光大气传输效应的重要方法,通过CCD接收外场光斑图像,通过matlab处理CCD接收到的近场和外场光斑图像,最后对影响光斑处理结果的方法进行了分析,并采用matlab编制了光斑处理界面。

一种光斑图像加速处理算法研究

在激光光束质量测量领域中,高分辨率图像能够提高测量精度,然而对于多点采样测量,全帧图像算法会导致测量时间的大大延长。为解决此问题,提出一种基于局部图像的光斑加速处理算法:根据前三个采样点激光参数,计算出光束空间传播路径,预测下一采样点计算区域,在此区域内计算相应参数。实验结果表明:对于单个采样点,图像分辨率1392×1040,该算法能够有效地降低信息处理量,全帧图像平均测量时间为0.926s,加速处理算法平均测量时间为0.512s,有效地减少单点采样全帧图像处理时间的45.27%。能够准确地计算出激光性能参数,提高整体测量速度,对高分辨率图像在激光光束质量测量中的应用具有重要意义。

基于机器视觉的罐道偏斜度检测系统

罐道受压力影响可能出现偏斜的情况,而目前常用的铅垂线法存在效率低、精度低的问题。研究了一种基于机器视觉的罐道偏斜度检测系统,由激光垂准仪、相机、光屏及嵌入式控制器组成,利用机器视觉技术测量垂准仪投射的光斑中心坐标,完成基准中心的标定和罐道偏斜度的测量;并通过相关实验验证了系统的准确性及可靠性。

Application of Laser Speckle Technology on the Detection of Agricultural Products

[Objective] The research aimed at investigating the application of laser speckle technology in agricultural products detection.[Method] This article described the basic principle of the laser speckle technology,provided a review of application development of the laser speckle technology in agricultural products detection,analyzed the problems in agriculture products detection using laser speckle technology and described the prospects of laser speckle technology in agricultural products detection.[Result] The laser speckle technology is a non-destructive detection technology for quality determination of agricultural products,which can be used to classify the agricultural products reasonably according to the quality of agricultural products.[Conclusion] The article provided reference and consult for laser speckle detection technology research.

激光自动对焦中离焦量的探测与计算方法

根据激光光线聚焦状态不同对应被测面上激光光斑形状不同的特点,通过引入辅助激光束,分析了调焦CCD采集的激光光斑图像信息,进而根据光斑形状及半径等信息确定被测面对焦状态。针对实验中每隔相同离焦距离采集的一系列光斑图像,提出了相应的图像处理方案,以提取所需光斑半径信息,进而进行光斑半径与离焦量转换。实验结果表明,光斑半径与离焦量呈线性关系,最大线性范围灵敏度为2.342像素/μm,最高可实现0.43μm分辨率。

Modified Laser Speckle Imaging with Adaptive Window

One of the advantages of laser speckle is detecting microvascular through image processing. This paper proposes a new image processing method for laser speckle, adaptive window method that adaptively processes laser speckle images in the space. Disadvantage of conventional fixed window method is that it uses the same window size regardless of target areas. Inherently laser speckle contains undesired noise. Thus a large window is helpful for removing the noise, but it results in low resolution of image. Otherwise a small window may detect micro vascular but it has limits in noise removal. To overcome this trade-off, the concept of adaptive window method is newly introduced to conventional laser speckle image analysis. In addition, the modified adaptive window method applied to other selection images. We have compared conventional Laser Speckle Contrast Analysis （LASCA） and its variants with the proposed method in terms of image quality and processing complexity, Moreover compared the result of the accompamed changing sdection images have also been compared.

ICA Based Speckle Filtering for Target Extraction in SAR Images Using Adaptive Space Separation

A novel approach based on independent component analysis (ICA) for speckle filtering and target extraction of synthetic aperture radar (SAR) images is proposed using adaptive space separation with weighted information entropy (WIE) incorporated. First the basis and the independent components are respectively obtained by ICA technique, and WIE of the image is computed; then based on the threshold computed from function T-WIE (threshold versus weighted-information-entropy), independent components are adaptively separated and the bases are classified accordingly. Thus, the image space is separated into two subspaces: "clean" and "noise". Then, a proposed nonlinear operator ABO is applied on each component of the 'clean' subspace for further optimization. Finally, recovery image is obtained reconstructing this subspace and target is easily extracted with binarisation. Note that here T-WIE is an interpolated function based on several representative target SAR images using proposed space separation algorithm.