天津大学精密测试技术及仪器全国重点实验室，天津 300072
为满足大尺寸测量仪器性能与制造水平提升的需求，基于非正交轴系架构理念对激光经纬仪进行设计。针对非正交轴系经纬仪在无参考末端情况下计算反向运动旋转角度的难题，提出反向运动线性模型，以实现旋转角度的快速、高精度计算。首先，基于李群李代数基本理论构建非正交轴系经纬仪正向运动学模型。其次，构建空间目标点与视准轴位姿参数间的约束关系，并结合旋转角度误差传递模型，确立用于求解旋转角度误差修正值的线性方程组。最终通过旋转角度初始估计值与误差修正值线性相加，获取高精度的反向旋转角度值。仿真结果表明，该方法所计算的旋转角度误差趋近于0，真实实验的旋转角度误差均小于0.02 mrad，验证了所提反向运动学线性模型的可行性与实用性。
光学仪器 非正交轴系 反向运动 线性模型 误差传递
浙江大学光电科学与工程学院, 浙江 杭州 310027
提出一种基于波导理论的针孔点衍射波前分析方法。该方法将针孔作为圆形波导,采用解析法求解波导的模式进而得到针孔后端面电场分布;根据矢量衍射理论推导出衍射波前的远场分布,最后详细分析了针孔透光率、衍射波前的强度与相位。结果表明,波导边界条件使针孔后端面各电场分量旋转不对称,使像散成为衍射波前的主要像差。为使透光率大于0,针孔直径必须大于0.6λ(λ为波长),以保证针孔中存在满足波导传输条件的模式。衍射波前两电场分量振幅分布的不同使衍射波前强度分布不具有旋转对称性,两者的相位差使衍射波前成为椭圆偏振光。该仿真结果为点衍射干涉仪中针孔结构的设计提供了重要的参考。
测量 点衍射波前 电磁光学 光学仪器 光学学报
2019, 39(11): 1112001
Author Affiliations
Abstract
Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
We implemented a stitching swing arm profilometer (SSAP) test for the inner and outer regions of a large aspheric surface with a short arm. The SSAP was more capable of improving sampling density of surface and was less sensitive to system error, like vibration noise and air-table noise. Firstly, a calculation model was built to evaluate the sampling density of the SSAP test. Then, sensitivity to system noise was tested when different lengths of arm were used. At the end, an experiment on a 3 m diameter aspheric mirror was implemented, where test efficiency was promoted, and high sampling density was achieved.
220.1250 Aspherics 220.4840 Testing 120.3940 Metrology 120.4640 Optical instruments Chinese Optics Letters
2019, 17(11): 112201
浙江大学能源清洁利用国家重点实验室, 浙江 杭州 310027
设计了一种基于全场彩虹测量技术的紧凑型彩虹折射仪。该折射仪采用笼式结构和全密封设计,光路的整体尺寸明显小于传统的彩虹光路,折射仪的尺寸为0.42 m×0.42 m×0.15 m。使用该彩虹折射仪对单组分液滴折射率、双组分液滴浓度进行了一系列实验测试。采用去离子水喷雾测试了折射仪的折射率测量精度,测量误差约为2×10
-4。测量了体积分数为0~100%的乙醇液滴的折射率,与文献数据进行了对比,并分析了误差来源。结果表明,所研发的紧凑式折射仪具有测量液滴折射率的功能,以及体积小、精度高的优点,适用于工业生产环境,在喷雾场测量中具有很好的应用前景。
测量 光学仪器设计 彩虹折射仪 喷雾液滴 折射率 激光与光电子学进展
2019, 56(10): 101201
1 中国科学院 光电技术研究所, 四川 成都610209
2 电子科技大学 光电科学与工程学院, 四川 成都610054
3 中国科学院大学, 北京100049
燃料组件变形状态是堆芯运行过程中的重要监测指标, 基于水下双目视觉的变形检测系统不仅能获得燃料组件关键参数的三维尺寸, 还可以测量组件的整体轮廓。根据水下大型燃料组件的高热、高辐射特点, 研制了一种基于16台摄像单元的水下双目检测系统, 并给出各组成模块的详细设计; 通过联合Harris特征点和区域灰度互相关方法, 实现辐射噪声干扰下的双目摄像模块的组内快速图像配准。经模拟水池和核电现场实验, 验证系统局部参数测量精度优于0.2 mm, 全局参数测量精度满足0.5 mm, 为高热、高辐射的水下乏燃料组件的局部变形和整体弯曲等参数测量提供有力工具。
光学仪器 水下双目视觉 燃料组件测量 特征匹配 optical instruments underwater binocular vision fuel assembly measurement feature matching
Author Affiliations
Abstract
1 School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China
2 University of Chinese Academy of Sciences, Beijing 100853, China
3 Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
This Letter proposes a snapshot imaging spectrometer, which obtains the spectral information and spatial information in one “shot”. The device proposed can achieve the data cube size of 21×29×40 in the waveband of 400–800 nm. The core element of this system is the microlens array, which contains 60×60 microlenses in a square arrangement, each microlens has an aperture of 125 μm×125 μm, and the F number is 15. The microlens array is mounted in a rotation mount, which provides 360° of rotation around the optical axis to maximize the spectral resolution. The final resolution of the system is about 10 nm.
110.4234 Multispectral and hyperspectral imaging 120.4640 Optical instruments 300.6190 Spectrometers Chinese Optics Letters
2019, 17(1): 011101
长春理工大学 光电工程学院,吉林 长春 130022
针对国家电网系统在防污闪工作中, 无法在线测量电气设备爬电距离的现状，基于双目立体视觉研制了一种高压绝缘子爬电距离的带电检测系统。提出了利用圆锥面离轴反射镜产生线结构光的方法。利用窄带滤光片增强了线结构光在图像中的对比度，并结合最大类间方差法和灰度重心法对图像进行自适应阈值分割，实现了特征点的自动提取，解决了强太阳光和复杂背景对特征点提取的干扰问题。通过系统标定后，对高压绝缘子样品的爬电距离进行了精度测试，实验结果表明最大相对误差为1.45%，平均相对误差为0.69%，已成功应用于110 kV变电站中各种绝缘子爬电距离的在线带电测量。
光学仪器 双目立体视觉 高压绝缘子 在线检测 optical instruments binocular stereo vision high voltage insulator on-line measurement
Author Affiliations
Abstract
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China
Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced noise by the sideband locking technique. Besides choosing an optimized modulation depth and different clockwise and counterclockwise modulation frequencies, the sideband is locked to the cavity resonance. With the proper modulation frequency, the carrier frequency component locates at a position far away from the resonant frequency, and then it is suppressed by the cavity itself, which can be taken as a bandpass filter. The amplitude of the carrier frequency can be suppressed by 20–25 dB additionally by the cavity and the total intensity suppression ratio can reach 115.74 dB. The backscattering induced noise can be eliminated for the adoption of different frequencies. The method can realize a stable and high suppression ratio without high requirements for parameter accuracy or device performance.
060.2800 Gyroscopes 010.1350 Backscattering 060.2370 Fiber optics sensors 120.4640 Optical instruments Chinese Optics Letters
2018, 16(1): 010608
