Author Affiliations
Abstract
1 College of Computer Science and Electronic Engineering, Hunan University, Changsha 410082, China
2 School of Computer Science, Hubei University of Technology, Wuhan 430068, China
The array spatial light field is an effective means for improving imaging speed in single-pixel imaging. However, distinguishing the intensity values of each sub-light field in the array spatial light field requires the help of the array detector or the time-consuming deep-learning algorithm. Aiming at this problem, we propose measurable speckle gradation Hadamard single-pixel imaging (MSG-HSI), which makes most of the refresh mechanism of the device generate the Hadamard speckle patterns and the high sampling rate of the bucket detector and is capable of measuring the light intensity fluctuation of the array spatial light field only by a simple bucket detector. The numerical and experimental results indicate that data acquisition in MSG-HSI is 4 times faster than in traditional Hadamard single-pixel imaging. Moreover, imaging quality in MSG-HSI can be further improved by image stitching technology. Our approach may open a new perspective for single-pixel imaging to improve imaging speed.
single-pixel imaging array spatial light field measurable speckle gradation Chinese Optics Letters
2024, 22(3): 031104
南开大学 电子信息与光学工程学院, 天津 300350
介绍了一种基于光纤传感技术的等截面悬臂梁固有频率的测量方法, 并采用理论计算和软件仿真对其进行了验证。首先, 理论推导了粘贴于悬臂梁表面的光栅中心波长与其所在位置处挠度的关系; 然后, 根据分析结果, 搭建了实验测量系统, 该实验采用高温火焰烧断连接线的方法产生一个初始的阶跃信号, 测量结果为20.093Hz; 接着, 采用里兹法对梁固有频率进行理论计算, 结果为20.311Hz; 最后, 利用ANSYS软件对悬臂梁进行模态分析, 得到梁的一阶模态为20.44Hz。实验测量结果与理论计算、有限元仿真结果十分接近, 证明了该方法是正确、可行的, 为悬臂梁固有频率的获取提供了新思路。
等截面悬臂梁 固有频率 光栅 阶跃信号 模态分析 uniform cantilever beam natural frequency optical grating step signal modal analysis
1 江苏科技大学材料科学与工程学院, 江苏 镇江 212003
2 南京宝色股份公司, 江苏 南京 211178
为了满足工业生产中提出的结构轻量化要求, 采用IPG光纤激光器对薄板T型接头进行了激光穿透焊试验, 通过改变激光穿透焊工艺参数, 研究不同热输入对焊接接头显微组织及接头尺寸变形量的影响, 并对接头显微硬度进行了测试和分析。结果表明, 随着热输入的增加, 焊缝熔深增大, 焊缝及热影响区晶粒尺寸增加, 焊缝内马氏体的含量减少, 焊缝及热影响区内显微硬度呈下降趋势; 焊缝组织为马氏体和上贝氏体, 粗晶区为贝氏体和少量马氏体, 细晶区为粒状贝氏体和珠光体; 焊缝及热影响区的显微硬度值均高于母材。
激光技术 激光焊接 激光穿透焊 T型接头 laser technique laser welding laser penetrate on welding T-joints
