1 Department of Physics, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
2 Department of Mining Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
3 College of Information Science and Engineering, Fujian Provincial Key Laboratory of Light Propagation and Transformation, Huaqiao University, Xiamen, Fujian 361021, China
Correlation holography uses incoherent light to reconstruct holograms. This technique reconstructs objects as distributions of two-point coherence function rather than using optical fields, as in conventional holography. The basic principle of correlation holography is derived from the van Cittert--Zernike theorem and relies on the similarity between the optical field and the coherence functions. Experimental implementation of the correlation holography techniques requires a field or intensity interferometer, and fringe analysis and cross-covariance measurement in these interferometers require a conventional camera with array detectors. With the availability of digitally controlled diffractive elements, it is possible to replace the incoherent light source, such as a rotating ground glass, with a digital source loaded with the random patterns in sequence. Such strategies ease the burden on the detector and allow for correlation holography with a single-pixel detector (SPD) to be used. This review paper discusses a close connection between digital holography and correlation holography. The principles of correlation holography with the SPD are reviewed in detail, and the advantages of using digital sources to mimic incoherent illumination in the correlation holography are examined in the context of three-dimensional and complex field imaging.
imaging systems correlation holography single-pixel detector digital holography coherence optics phase recovery 激光与光电子学进展
2021, 58(10): 1011011
Author Affiliations
Abstract
1 College of Information Science and Engineering, Huaqiao University, Xiamen 361021, China
2 Department of Physics, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India
3 CREOL, College of Optics and Photonics, University of Central Florida, Orlando, FL 32816-2700, USA
4 Fujian Provincial Key Laboratory of Light Propagation and Transformation, Huaqiao University, Xiamen 361021, China
Encoding information using the topological charge of vortex beams has been proposed for optical communications. The conservation of the topological charge on propagation and the detection of the topological charge by a receiver are significant in these applications and have been well established in free-space. However, when vortex beams enter a diffuser, the wavefront is distorted, leading to a challenge in the conservation and detection of the topological charge. Here, we present a technique to measure the value of the topological charge of a vortex beam obscured in the randomly scattered light. The results of the numerical simulations and experiments are presented and are in good agreement. In particular, only a single-shot measurement is required to detect the topological charge of vortex beams, indicating that the method is applicable to a dynamic diffuser.
intensity correlation vortex beam scattering Chinese Optics Letters
2021, 19(2): 022603
