High-resolution computational ghost diffraction with shaped incoherent sources and its applicability in coherent diffraction imaging

Abstract

Computational ghost diffraction (CGD) with a higher-order cosh-Gaussian modulated incoherent source is investigated theoretically. The corresponding numerical simulations are given to see clearly the effects of the parameters of the higher-order cosh-Gaussian source on the imaging quality. Our results show that the resolution of the CGD patterns can be significantly improved by properly varying the source parameters. In addition, we numerically study the effect of the propagation distances in the CGD system and explore the CGD applicability in coherent diffraction imaging. These results may be helpful for implementation of high-resolution x-ray diffraction.

Lensless ghost imaging with hollow-Gaussian modulated incoherent sources in atmospheric turbulence

“…The results showed that imaging quality can be degraded by the turbulence [18,20]. In recent years, source-shaping techniques have been presented to improve imaging quality in the GI [22][23][24][25][26]. Luo et al demonstrated that the shaped cosh-Gaussian incoherent source and multi-Gaussian incoherent source can improve the quality of GI under atmospheric turbulence [22,24].…”

“…Luo et al demonstrated that the shaped cosh-Gaussian incoherent source and multi-Gaussian incoherent source can improve the quality of GI under atmospheric turbulence [22,24]. In fact, the central intensity will be depressed in the source plane by increasing the modulation parameters of the cosh-Gaussian source [25], which is not good for the imaging process. Note that studies have proved that the hollow-Gaussian source can resist the effect from the turbulence to some extent, and its intensity distribution can develop into a Gaussian distribution with the increase of the propagation distance [27,28], which may compensate for the loss of imaging quality due to the weak central intensity of the shaped-Gaussian source plane.…”

The unified imaging condition of Fourier-transform ghost imaging in the far field

“…the distances between the light source and the two detectors are equal [15]. Based on this condition, many theoretical and experimental works have been implemented [16][17][18][19][20][21][22][23], including three-order LGD [16],…”

“…LGD with a modulated incoherent source [20,21] and coded Fourier-transform ghost imaging [23]. In fact, the condition is applicable in the near field.…”

Second-order intensity-correlated imaging with a rotating reflected object

“…Later, people found that GD can be performed with the true thermal and pseudothermal light [9,10], which is always implemented by two ways: one is to use a coherent source together with optical components with a small speckle size such as a rotating glass, the advantage of this way is that the resolution and the contrast of the imaging system can be controlled by adjusting the speckle size and the variation rate. The other is the use of the spatial light modulator, which corresponds to a simpler apparatus [11]. The pesudothermal light is not limited by the application mode and detection capability compared with other sources and thus it has been widely utilized in the study of GD in recent years [9][10][11][12][13][14][15][16][17][18][19][20], such as phase and amplitude retrieval [13], third-order lensless imaging [15] and sparsity constraints [17].…”