Parallel two-step phase-shifting digital holography

Abstract

We propose a parallel two-step phase-shifting digital holography technique capable of instantaneous measurement of three-dimensional objects, with a view toward measurement of dynamically moving objects. The technique is based on phase-shifting interferometry. The proposed technique carries out the two-step phase-shifting method at one time and can be optically implemented by using a phase-shifting array device located in the reference beam. The array device has a periodic two-step phase distribution, and its configuration is simplified compared with that required for three-step and four-step parallel phase-shifting digital holographies. Therefore the optical system of the proposed technique is more suitable for the realization of a parallel phase-shifting digital holography system. We conduct both a numerical simulation and a preliminary experiment in the proposed technique. The results of the simulation and the experiment agree well with those of sequential phase-shifting digital holography, and results are superior to those obtained by conventional digital holography using the Fresnel transform alone. Thus the effectiveness of the proposed technique is verified.

A practical inverse-problem approach to digital holographic reconstruction

“…Several solutions have been proposed for reconstruction following these approaches [3,4]. The corresponding algorithms are presently used in practice and incorporated in digital holographic microscopy for instance.…”

Single-step method for fiber-optic probe-based full-range spectral domain optical coherence tomography

“…They can be categorized into the multi-and single-frame methods. As the multi-frame method, the phase shifting [5][6][7][8][9][10] and the simultaneous multiple detection method [11,12] were researched. For the single-frame method, the BM scan [13] (B-scan: lateral scan, M-scan: reference mirror scan), the B-scan-based Hilbert transform reconstruction [14], and the phase shift between two A-lines [15] methods have been proposed.…”

“…However, it requires several interferograms at the same location to build a single complex A-line, which is time consuming; the two-step phase-shifting method has been adopted particularly because it demands just two interferograms [6,7,9,10]. By utilizing multiple spectrometers [11] or a 3 × 3 coupler [12] for parallel detections, two interferograms of a phase difference could be simultaneously captured.…”

2-step Quadrature Phase-shifting Digital Holographic Optical Encryption using Orthogonal Polarization and Error Analysis

“…[15][16][17][18] Especially the 2-step phase-shifting interferometric technique is applied to cryptography. [19][20][21][22][23][24] In the previous papers [20,21,24], we proposed an optical encryption system using 2-step phase-shifting digital holography. In the proposed optical system, a PZT driven mirror was used to get a quadrature phase shift of π/2 in the reference beam path of the Mach-Zehnder interferometer.…”