Ghost imaging through inhomogeneous turbulent atmosphere along an uplink path and a downlink path

Abstract

Ghost imaging through inhomogeneous turbulent atmosphere along an uplink path and a downlink path is studied in detail by using the numerical simulation method. Based on the Hufnagel-Valley5/7 turbulent atmosphere profile model, the numerical imaging formula of ghost imaging through turbulent atmosphere along a slant path is derived and used to analyze the influence of turbulent atmosphere along an uplink path and a downlink path on the imaging quality, and the effect from the zenith angle is also discussed. The numerical results show that the imaging quality through turbulent atmosphere along a downlink path is better than that along an uplink one, which can be explained by the phase modulation effect.

Effect of uneven temperature distribution on underwater computational ghost imaging

“…In our experiment, the underwater environment can be regarded as the modulation of the light field. As we all know, premodulation from the path disturbance has greater influence than post-modulation [29]. Thus, imaging quality in position A could be inferior when compared with that in position C. Similarly, the average intensity distribution of laser source propagating through different positions of the underwater environment at 92 • C is depicted in figure 6 to prove our analysis.…”

The influence of free-surface vortex on underwater ghost imaging

“…From the previous works, the closer the path disturbance (scattering media [17] and atmospheric turbulence [30]) is to the object, the smaller the impact from the disturbance on imaging quality is. It is mainly because effect of the two typical channel disturbances on light transmission can be described by random phase modulation, and the disturbance effect on optical propagation is changed from pre-modulation to post-modulation when the disturbance position is changed from near the light source to far away from the source [30]. While, it is surprising to find that imaging quality drops sharply when the vortex is far away from the source in our experiments.…”

“…In this paper, effect of the vortex with different positions and rotation speeds on UGI is investigated experimentally. It is shown that imaging quality becomes better when changing the position of the vortex away from the object, which is absolutely different from typical path disturbance influence of atmospheric turbulence and scattering that smaller impact on imaging quality is imposed when the disturbance is closer to a target [17,30]. The counter-intuitive influence is explained by the variation mechanism of speckle pattern and the effective bucket data herein, based on which a modified GI method is proposed to enhance imaging quality.…”

High-performance deep-learning based polarization computational ghost imaging with random patterns and orthonormalization

“…It simplifies the light path and improves the performance of ghost imaging. In comparison to traditional imaging, CGI has already prohibited great potentials in applications, such as single-pixel imaging [5,6], biological imaging [7][8][9][10], information encryption [11][12][13], laser radar technique [14,15] and imaging through atmospheric turbulence environment [16][17][18][19][20][21]. However, the reflectivity or transmittance of targets are sometimes close to the background in many real-world scenarios, making it difficult to identify the targets from the background by the received light intensity.…”