Annular Light Source Fizeau Interferometer System Design And Research, And

At present, the laser interferometer is adversely affected by coherent artifacts and influence the precision during the high resolution and precision interference optical testing, Using RoF illumination technical, coherent superposition of unwanted radiation generated in the interferometer will be suppressed. In this dissertation, as far as the light source of the system is concerned, some meaningful results are obtained as follows.Firstly, from the theoretical of coherence optical imaging system, as to suppress the coherent artifacts, the characteristic of RoF illumination method in the inferometric system has been analyzed, which can reduce the effects of coherent artifacts, and preserve the fringe visibility.Secondly, compared the spatial coherence of RoF and the quasi-point light source, got the intensity distribution of interference field through the Van Cittert-Zernike theorem and fringe visibility expression. And also, error problems arised from off-axis illumination has been simulated, furthermore, the fringe visibility relationship with RoF radius, radius thickness and interference cavity length has been presented.Thirdly, the component of produce the RoF has been developed with Zemax, in order to verify the RoF could reduce the coherence artifacts and preserved the fringe visibility, theφ100mm interferometer has been modeled. Then, under the same noise condition, compared to the traditional point source, the performances show clearly the coherent artifacts on the interferogram are suppressed with RoF illumination method.To sum up, this dissertation presents a comprehensive analysis interferometer with RoF illumination method, the results offer us a better understanding of the characteristic of RoF, which could reduce coherence artifacts, so it will be helpful to improve system S/N ration and broaden the measurement spatial frequency of interferometer.