Digital holographic microscopy with physical phase compensation

Abstract

An optical configuration for digital holographic microscopy is presented. Digital off-axis holograms are recorded by using a single-cube beam splitter in a nonconventional configuration so as to both split and combine a diverging spherical wavefront emerging from a microscope objective. When a plane numerical reference wavefront is used for the reconstruction of the recorded digital hologram, the phase curvature introduced by the microscope objective together with the illuminating wave to the object wave can be physically compensated.

Generation of Optical Vortex Arrays Using Single-Element Reversed-Wavefront Folding Interferometer

“…Gaussian beam (TEM 00 fundamental mode) from a CW green laser having power 30 mW and wavelength λ = 532 nm was expanded and spatially filtered (BE/SF) and a divergent beam was then made incident on to the 50/50 CBS (size 50 mm × 50 mm). The CBS was kept in unconventional position so as to both split and combine the diverging spherical wave fronts [29,30]. A light beam having spherical wave front (diameter 20 mm) traveling along the z-axis was made incident on the CBS with its central semireflecting layer placed along the propagation direction.…”

“…If the orientation angle of the IFP 1 is changed, orientation angle of the IFP 2 will also change accordingly. The orientation and the spatial carrier frequency of the IFP 1 and 2 can be easily controlled by means of changing angle θ [29,30]. The two interferograms IFP 1 and 2 are highly diverging and as the distance of propagation increases they start overlapping to each other.…”

“…Multiple wavefronts are generated and combined by means of simple interferometric configurations. Similar situation of CBS was used earlier for measuring the degree of coherence [28], optical metrology [29], and digital holographic microscopy [30]. Two new interferometric configurations were used for generating a variety of vortex lattices.…”

Unambiguous 3D Surface Measurement Method for a Micro-Fresnel Lens-Shaped Lenticular Lens Based on a Transmissive Interferometer

“…A laser is normally used as a light source in the transmissive interferometer. A phase shifting interferometer (PSI) and a digital holographic microscope have been actively researched in recent decades [8,9]. In this paper, we describe the advantages of transmissive laser interferometer in measuring optical components as compared to using a reflective white light interferometer and AFM.…”

Intermediate Holographic Data Storage System by Using Sequentially Superimposed Recording

“…Holography is very useful and interesting technology in many optical areas such as optical components [1], display [2,3], microscopy [4,5] and so on. Also, holographic storage technology is one of the most extensively studied mass storage technologies in recent years because of the extended internet usage, the development of three dimensional display systems, and therefore the great demand for mass storage systems.…”