Object reconstruction from in-line Fresnel holograms without explicit depth focusing

We propose two computational techniques for extracting object cross-sectional shape information from digitized in-line Fresnel holograms that do not require prior knowledge of object depths but recover relative depth information along the way. The first algorithm is applicable to hologram segments involving a single particle only. It is based on estimating Fourier transform magnitude and phase of the particle from those of the hologram segment. The second algorithm conducts a joint inverse filtering and depth search procedure so as to minimize (or maximize) a binariness (or a concentration) criterion defined over the output object function. It is applicable to multiple-particle, multiexposure holograms as well. The proposed techniques are illustrated on synthesized holograms and their practical limitations are discussed. C 2004 Society of Photo-Optical Instrumentation Engineers.


Lens optics and the continuity problems of the ABCD matrix
Baskal, S.; Kim, Y. S. (Informa UK Limited, 2014-01-19)
Paraxial lens optics is discussed to study the continuity properties of the ABCD beam transfer matrix. The two-by-two matrix for the one-lens camera-like system can be converted to an equi-diagonal form by a scale transformation, leaving the off-diagonal elements invariant. It is shown that the matrix remains continuous during the focusing process, but this transition is not analytic. However, its first derivative is still continuous, which leads to the concept of 'tangential continuity'. It is then shown t...
Efficient computation of 2D point-spread functions for diffractive lenses
Ayazgok, Suleyman; Öktem, Sevinç Figen (The Optical Society, 2020-01-10)
Diffractive lenses, such as Fresnel zone plates, photon sieves, and their modified versions, have been of significant recent interest in high-resolution imaging applications. As the advent of diffractive lens systems with different configurations expands, the fast and accurate simulation of these systems becomes crucial for both the design and image reconstruction tasks. Here we present a fast and accurate method for computing the 2D point-spread function (PSF) of an arbitrary diffractive lens. The method i...
Compressive spectral imaging with diffractive lenses
Kar, Oguzhan Fatih; Öktem, Sevinç Figen (The Optical Society, 2019-09-15)
Compressive spectral imaging enables the reconstruction of an entire 3D spectral cube from a few multiplexed images. Here we develop a novel compressive spectral imaging technique using diffractive lenses. Our technique uses a coded aperture to spatially modulate the optical field from the scene and a diffractive lens such as a photon sieve for both dispersion and focusing. Measurement diversity is achieved by changing the focusing behavior of the diffractive lens. The 3D spectral cube is then reconstructed...
Deep iterative reconstruction for phase retrieval
Isil, Cagatay; Öktem, Sevinç Figen; Koc, Aykut (The Optical Society, 2019-07-10)
The classical phase retrieval problem is the recovery of a constrained image from the magnitude of its Fourier transform. Although there are several well-known phase retrieval algorithms, including the hybrid input-output (HIO) method, the reconstruction performance is generally sensitive to initialization and measurement noise. Recently, deep neural networks (DNNs) have been shown to provide state-of-the-art performance in solving several inverse problems such as denoising, deconvolution, and superresoluti...
Performance of M-ary pulse position modulation for aeronautical uplink communications in an atmospheric turbulent medium
Ata, Yalcin; Baykal, Yahya; Gokce, Muhsin Caner (The Optical Society, 2019-10-01)
This paper discusses the bit-error-rate (BER) performance of an aeronautical uplink optical wireless communication system (OWCS) when a Gaussian beam is employed and the M-ary pulse position modulation technique is used in an atmospheric turbulent medium. Weak turbulence conditions and log-normal distribution are utilized. The Gaussian beam is assumed to propagate on a slant path, the transmitter being ground-based, and the airborne receiver is on-axis positioned. Variations of BER are obtained against the ...
Citation Formats
M. Ozgen and T. E. Tuncer, “Object reconstruction from in-line Fresnel holograms without explicit depth focusing,” OPTICAL ENGINEERING, pp. 1300–1310, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36479.