• Acta Photonica Sinica
  • Vol. 51, Issue 4, 0412007 (2022)
Shinan ZHOU, Xiaoyan SHEN*, Dongsheng LI, and Chenguang WU
Author Affiliations
  • College of Metrology & Measurement Engineering,China Jiliang University,Hangzhou 310018,China
  • show less
    DOI: 10.3788/gzxb20225104.0412007 Cite this Article
    Shinan ZHOU, Xiaoyan SHEN, Dongsheng LI, Chenguang WU. Self-calibration Correction Measurement of Micro-angle Based on F-P Etalon Multi-beam Interference Imaging[J]. Acta Photonica Sinica, 2022, 51(4): 0412007 Copy Citation Text show less

    Abstract

    The demand for high-accuracy measurement of micro-angle in modern industries is getting higher and higher, and its measurement methods and measurement technologies are also constantly improving. At present, The micro-angle measuring instrument with the highest accuracy in the world is the ELCOMAT HR photoelectric autocollimator produced by M?LLER-WEDEL in Germany, and its angle measurement uncertainty within the range of 300″ can reach 0.06″ (k=2). And the highest accuracy in China is the AUTOMAT 5 000 photoelectric autocollimator produced by Tianjin Automate Optoelectronics Co., which can achieve a measurement accuracy of ±0.25″ within the range of ±1 000". With the continuous improvement of the precision of micro-angle measurement, higher and higher requirements are put forward for the angle calibration, and some traditional angle calibration methods are difficult to meet the current needs. Therefore, using the self-calibration technology to realize micro-angle measurement has become a research hotspot in recent years. The current angle self-calibration technology mainly focuses on the measurement of the circumference angle with the characteristic of circle closure, and there are few studies on the self-calibration measurement of micro-angle. In the early stage, our research group proposed a micro-angle measurement system based on F-P etalon, which used the displacement of the concentric rings in the focal plane after F-P multi-beam interference ring imaging to achieve micro-angle measurement, and pointed out the possibility of using the system to realize the micro-angle self-calibration measurement. This paper provides a comprehensive review and summary of the self-calibration method for this micro-angle measurement. The key point of this self-calibration method is to use the exact fraction method to measure the exact value of the F-P etalon interval, and then accurately calculate the relative focal length of the imaging objective lens, and combine the relative displacement caused by the small angle, so as to realize the self-calibration of the micro-angle measurement. The main research work of this paper is as follows: 1) The principle and method of the self-calibration measurement of the micro-angle measurement system are systematically and detailedly sorted out, and the calculation method of exact fraction method is described in detail, and the complete micro-angle self-calibration measurement process is finally obtained. 2) Special consideration is given to the effect of the algorithm error of the exact fraction method, temperature and humidity on the measurement results of the F-P etalon. The interference image under the theoretical interval d0 is obtained through simulation by MATLAB, and the calculated interval d1 of the F-P etalon under this condition is obtained by using the exact fraction method, and compared with the theoretical interval d0, the algorithm error and the temperature and humidity error of the exact fraction method are obtained, and the correction of the calculation result of the F-P interval is realized. 3) The self-calibrated micro-angle measurement experiments are carried out, and the accurate interval of the F-P etalon in the current environmental conditions is measured. Combined with the simulation method in 1), the corrected value under the current environmental conditions is obtained, and finally the corrected etalon interval is obtained, which is d '=(2 014.986 5±0.000 3) μm. The focal lengths of the imaging objective and the micro-angle measurement results before and after self-calibration are obtained. The measurement results show that under the current experimental conditions, the relative expanded measurement uncertainty of the focal length after self-calibration has reduced from 0.014 to 0.007, while the angle measurement uncertainty in 600" has decreased from 0.132″ to 0.084″, which promotes the accuracy of micro-angle measurement greatly.
    Shinan ZHOU, Xiaoyan SHEN, Dongsheng LI, Chenguang WU. Self-calibration Correction Measurement of Micro-angle Based on F-P Etalon Multi-beam Interference Imaging[J]. Acta Photonica Sinica, 2022, 51(4): 0412007
    Download Citation