| Correlation imaging is also called ghost imaging or two-photon imaging.The correlation imaging of partially coherent light is a new imaging technology development direction due to its high imaging resolution and good atmospheric inhibition.Light transmission in turbulent atmosphere,the turbulent intensity associated with instability will affect the imaging quality,thus to study the effect of atmospheric turbulence on correlation imaging quality and carry out experimental research has important theoretical significance.In this thesis,further theoretical analysis,numerical simulation and experimental study are made on the performance of correlation imaging under atmospheric turbulence.Using the correlation imaging theory under non-Kolmogorov spectral atmospheric turbulence,the correlation imaging results of the double-slit object under different atmospheric turbulence parameters are obtained.In particular,the influence of the inner and outer scales of atmospheric turbulence on the correlation imaging is obtained.Based on the normalized correlation image of double-slit,the effects of atmospheric turbulence intensity,inner and outer scale,generalized index on image resolution are theoretically analyzed.Atmospheric turbulence intensity increasing(1×10-15m-2/3to1×10-13m-2/3),outer scale increasing?0.5 m to 100 m?,inner scale decreasing?0.010 m to 0.001 m?and generalized index decreasing?3.7 to 3.1?,cause a decline in the imaging resolution?the resolution of the corresponding parameters decrease respectively 1,0.27,0.44 and 0.46?.Using the method of phase screen,correlation imaging under the non-Kolmogorov spectrum atmospheric turbulence is simulated and analyzed of the atmospheric turbulence parameters on imaging resolution and signal-to-noise ratio.These results show that when the atmospheric turbulence intensity increases,the inner scale decreases,the outer scale increases,the generalized index decreases,and the imaging resolution and signal-to-noise ratio decrease.Atmospheric turbulence intensity increasing(1×10-1 7m-2/3to1×10-16m-2/3),outer scale increasing?0.5 m to 100 m?,inner scale decreasing?0.010 m to 0.001 m?and generalized index decreasing?3.8 to 3.2?,the imaging resolution parameters are corresponding to the drop of 0.2,0.61,0.06 and 0.18,respectively,SNR corresponding fell by 16.7%,32.8%,6.9%and 3.8%respectively,and the analysis of the correlation imaging resolution is consistent with the trend of the theoretical formula analysis.Using liquid crystal Spatial Light Modulator?SLM?to simulate the atmospheric turbulence,design and built the correlation imaging experimental system based on false thermal optical.The effect of turbulence parameters on the signal-to-noise ratio of correlated imaging under non-Kolmogorov spectrum is studied experimentally.Atmospheric turbulence intensity increasing(2×10-1 5m-2/3to3×10-14m-2/3),outer scale increasing?0.5m to 100 m?,inner scale decreasing?0.010 m to 0.001 m?and generalize index decreasing?3.8 to 3.2?,the object's imaging signal-to-noise ratio decrease respectively:14.5%,18.1%,7.7%and 4.6%.So that,the turbulence intensity and scale effect on imaging signal-to-noise ratio is bigger.The change trend of SNR with atmospheric turbulence parameters is consistent with the simulation results.The study with the influence of atmospheric turbulence parameters on correlation imaging under non-Kolmogorov spectrum has certain reference value and theoretical significance for restraining the influence of turbulence and expanding the application of correlation imaging in atmospheric environment. |
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