Experiment Research Of Correlation Between Coherence And Polarization Of Light

The coherence and polarization of light are two closely related aspects in statistical optics. The unified theory of coherence and polarization provides a new way for studying the characteristic of statistical optics of stochastic electromagnetic beams propagation, which is more precious and advanced. In this dissertation the cross-spectral density matrix was introduced at first, and the propagation model of stochastic electromagnetic beams was constructed. Then the propagation characteristics of interference between pinholes and complex optical systems were explored. Finally we performanced the experimental study on correlation between coherence and polarization. The paper is structured as follows.First, the define, propagation law and application of the cross-spectral density matrix were demonstrated. And then the models for stochastic electromagnetic beams propagating through double-hole interference, multi-hole interference, free space, atmospheric turbulence and focal optical systems were set up. After derivations, we obtained analytic expressions for the elements of cross-spectral density matrix on propagation.Second, through numerical simulating and calculating, the propagation characteristics of isotropic stochastic electromagnetic beams under the double-hole interference were studied. Analytic expressions for the stable spectral degree of polarization were obtained. And then the relation between coherence and polarization of light is studied. After that the propagation characteristics of triple-hole interference were considered, and the differences from double-hole interference were obtained.Third, through numerical simulating and calculating, the characteristics of anisotropic stochastic electromagnetic beams propagating through free space, atmospheric turbulence and focal optical systems were studied. Analytic expressions for the stable spectral degree of polarization were derived. The differences of propagation characteristics in free space and atmospheric turbulence were compared. In focal optical systems, the spectral degree of polarization at focal position equaled to the stable spectral degree of polarization in free space, which was proved. This study also provided and verified the universal conditions that complete polarized and complete non-polarized stochastic electromagnetic beams kept the spectral degree of polarization invariable. And the condition that the homogeneous distribution of the spectral degree of polarization was realized at propagation plane in focal optical systems was also provided.Fourth, a method of achieving Gaussian Shell-model beams in laboratory was introduced, and the function of each component in this system were pointed out. We measured relative value of spectral density and the spectral degree of coherence with CCD. And then the cross-spectral density matrix were obtained by means of fitting. The spectral degree of polarization at the initiative plane was measured with various methods, which was compared with the results calculated by the cross-spectral density matrix. The experiment results were proved to be reliable.Fifith, the non-polarized Gaussian Shell-model beams were constructed with two different He-Ne lasers. The spectral degree of polarization at the initial plane, the spectral degree of coherence, and the spectral degree of polarization under different conditions at a fixed axial point were measured. The results showed that the spectral degree of polarization was variable on propagation, and the correlation between coherence and polarization of light was explored. In this paper the causes of experimental error were analyzed, and the experimental results were discussed as well.