Lensless Fourier-transform ghost imaging with classical incoherent light

Abstract

The Fourier-Transform ghost imaging of both amplitude-only and pure-phase objects was experimentally observed with classical incoherent light at Fresnel distance by a new lensless scheme. The experimental results are in good agreement with the standard Fourier-transform of the corresponding objects. This scheme provides a new route towards aberration-free diffraction-limited 3D images with classically incoherent thermal light, which have no resolution and depth-of-field limitations of lens-based tomographic systems.

Ghost “pinhole” imaging in Fraunhofer region

“…However, we cannot obtain Fourier-transform ghost diffraction when both the object and the CCD camera D r , relative to the source, are located in Fraunhofer region. 7,12 In addition, in lensless ghost imaging schemes, the best resolution of ghost imaging in spatial domain is determined by the size of the speckle placed on the object plane ͑⌬x Ϸ z 1 / D͒. 13,14 As the transverse size of the thermal source is increased, if Eq.…”

“…Different from conventional pinhole imaging method, ghost imaging, based on the second-order correlation of light fields, can nonlocally image an object by two-photon interference involving a joint detection of two photons at distant space-time points with both entangled source and thermal light. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] In this letter, a lensless ghost pinhole camera is investigated when both the object and the reference detector, relative to the thermal source, are located in Fraunhofer region.In previous lensless ghost imaging systems, the object is adjacent to the test detector, so the test detector should be a bucket detector and collect all intensity information from the object ͑Refs. 2 and 3͒.…”

Step-by-step guide to reduce spatial coherence of laser light using a rotating ground glass diffuser

“…To realize the latter, several methods have been suggested including, induction of vibrations in a section of an optical fiber [9], scrambling the light by focusing the laser beam into a multi-mode optical fiber [10] or guiding the laser beam on a holographic diffuser [11]. However, one of the most common approach to remove coherent noise is positioning a rotating or vibrating ground glass diffuser in the beam path, producing a partially coherent light source [12][13][14][15][16][17][18][19][20][21][22][23][24]. To collect the scattered light from a diffuser single lenses with different focal lengths [20][21][22][23][24] or beam splitter cubes [16][17][18] are used in literature, offering only modest light collection.…”

Single-pixel digital ghost holography

“…A few attempts can be found in the literature. Using 2D phaseretrieval algorithms, the object's complex information can be extracted from the near-and far-field patterns [23,24], but only after rearranging the optical setup for each configuration. Another approach corresponds to that in Ref.…”