基于双光栅干涉仪测量透镜焦距技术研究
时间:2018-03-21 16:30 来源:毕业论文 作者:毕业论文 点击:次
| 摘要长焦距光学元件在惯性约束核聚变、光学遥感、激光聚焦收发系统和天文望远镜等大型光学系统中有着广泛的应用，针对长焦距的精确测量仍是光学测量领域的热点和难点。 本文研究了一种基于双光栅干涉仪的透镜焦距测量方法，通过对前一块Ronchi光栅泰伯像与后一块Ronchi光栅生成的莫尔条纹的倾角变化进行精确求解，以计算待测透镜的焦距。在泰伯莫尔效应的理论基础上推导了长焦距测量公式，并根据二次测量法对测量公式进行了优化。对光栅间距、栅线夹角和光栅常数等系统参数进行了分析，确定了最优参数。提出五棱镜扫描法对准直波前发生器进行装调；采用机械调节法装调光栅栅线夹角，装调精度可达 ；利用曲率半径22m的标准反射球面标定了光栅夹角为 ，标定精度优于0.1%，验证了栅线夹角的装调结果。 对焦距为59.38m的透镜进行了测量，重复性和稳定性均优于0.06%，测量精确度可达0.2%。在系统测量口径内，对焦距为39.95m的透镜进行了测量，最大相对误差优于1.2%。利用长焦发生器对系统测量范围30-500m进行了测量实验，并对测量结果进行了修正。实验结果表明这种方法可以实时的对长焦距进行高精度测量。19944 关键词 长焦距测量 泰伯效应 莫尔条纹 装调 标定 毕业设计说明书（论文）外文摘要 Title Research of the method for testing long focal length lens based on double-grating interferometer Abstract Long focal length optical elements are widely used in many optical systems such as ICF, optical remote sensing, optical antenna astronomical telescope and so on. The measurement for long focal length lens are still difficult problems in the field of optical measurement. In this paper, we present a novel method for testing the focal length lens of large aperture, which is realized by calculating the angle of moiré fringe formed by Talbot image of a Ronchi grating and another. The long focal length measurement formula is established base on the theory of Talbot effect and moiré fringe. The optimized formula is deduced base on the Twice-measurement method. The key parameters of system such as the distance between two gratings, the angle of grating lines, and the grating constant are designed based on the analysis of moiré fringe. A alignment method based on scanning pentaprism is introduced to measure the collimated wavefront. A mechanical method of regulating the angle of grating lines is used to ensure the error of the angle could be easily controlled within . A standard concave spherical reflector with radius of 22m is used to standardize the angle of grating lines as . The accuracy of standardization could reach 0.1%, which also demonstrated that the mechanical method was an effective way to regulate the angle of grating lines. The measurement system is used to test the lens with the theoretical focal length of 59.38m. The experimental results show that the repeatability and stability could both reached 0.06%, the accuracy of measurement is better than 0.2%. The concave lens with theoretical focal length of 39.95m is tested within the aperture of system from 50mm to 200mm and the maximum error is controlled within 1.2%. A long focal length generator is used to test the measurement range of the system from 30m to 500m, the experimental data were corrected to perform well and also demonstrated this method can be applied to the real-time long focal length measurement with high accuracy. Keywords Long focal length measurement Talbot effect Moiré fringe alignment calibration 目 次 1 引言 1 (责任编辑：qin) |