Polarization holography is a newly researched field, that has gained traction with the development of tensor theory. It primarily focuses on the interaction between polarization waves and photosensitive materials. The extraordinary capabilities in modulating the amplitude, phase, and polarization of light have resulted in several new applications, such as holographic data storage technology, polarization multiplexing, vector or vortex beams, and optical functional devices. In this paper, fundamental research on polarization holography with linear polarized light, a component of the theory of polarization holography, has been reviewed. Primarily, the effect of various polarization changes on the linear and nonlinear polarization characteristics of reconstructed light wave under continuous exposure and during holographic recording and reconstruction have been focused upon. The polarization modulation realized using these polarization characteristics exhibits unusual functionalities, rendering polarization holography as an attractive research topic in many fields of applications.
The old theory of polarization holography is based on Jones matrix formalism, where the angle between two lights to be interfered each other should be small, and the results are limited under the paraxial approximation. However, since the tensor theory of polarization holography was proposed, the research of polarized holography has become hot, and has made a lot of new progress. There are also many researching works of reconstruction characteristics have been reported. One of the examples is that multi-channel recording was applied to data storage high density recording. In this paper, the representative works are introduced.
Polarization holography has important research significance and application prospect. UV curing has a certain effect on polarization hologram. Using PQ/PMMA as the storage medium, the effects of UV curing on the quality and storage time of generated vector light field in the medium were studied.
Linear polarization holography based on tensor theory has yielded numerous intriguing discoveries and applications. Utilizing theories such as null reconstruction, applications beneficial for holographic optical storage have been realized, with dual-channel polarization multiplexing being one of them. However, previous research has found deviations in the grayscale ratios on reconstructed images compared to original images, especially when uploading grayscale images with higher levels, such as 4-level grayscale images. This study conduct experiments using different recording methods to identify the source of grayscale crosstalk from a single test image. The results indicate that the recording modes, whether co-polarized or orthogonal polarized, do not significantly disrupt amplitude recording.
This paper proposes a fabrication method for realizing all-optical AND and NOR logic gates based on polarization holography. During the recording process, two specially designed polarization holograms are recorded at the dual-region position of the polarization-sensitive material. During the reconstruction process, two reading waves in different directions are used as two input lightwaves. The background lightwave is added to the propagation direction of the two reconstructed waves, and the two reconstructed waves superimposed with the background lightwave are used as two output lightwaves. The light intensity of the two output lightwaves, together, defines the logic signal of the final output. The all-optical AND and NOR logic gates fabricated using this method have the advantages of simple structure, low cost, and fast response.
The reconstruction process of polarization holography needs to strictly meet the Bragg condition. This paper aims to study the Bragg condition in the reconstruction process of polarization holography. The Bragg mismatch will have a negative impact on the reconstructed recording information. It not only affects the diffraction efficiency of there constructed light in the original reference light direction, but also affects the reconstructed recording image. Based on PQ/PMMA, we studied the variation of the diffraction efficiency of the polarized hologram and its effect on there constructed recorded image under the condition of deviating from the Bragg condition.
In the tensor polarization holography theory, parameters A and B represent the scalar and tensor coefficients of the photo-induced change in the dielectric tensor, respectively. A/B is called the exposure response coefficient, a key factor for manipulating the polarization state of the reconstructed wave in polarization holography. We measure the initial exposure response coefficient of the polarization-sensitive material, phenanthrenequinone-doped polymethyl methacrylate (PQ/PMMA), and analyze the effect of the interference angle and the polarization states of the signal and reference waves on the coefficient in linear polarization holography. To better understand the linear polarization holography, we develop a formula to describe the law of the initial exposure response coefficient.
Polarization grating (PG) divides the incident wave into the left- and right-handed circularly polarized waves, the intensities of two waves depending on the state of polarization of incident wave. Large deflection angle of the commercial PG is usually made by the grating cascade due to the limit of grating period. While using the tensor polarization holography theory, arbitrary deflection angles of PGs have been designed, where the polarization-sensitive material phenanthraquinone-doped polymethyl methacrylate (PQ/PMMA) is utilized as the recording medium in our experiments. We have made PG with the deflection angle of 40°.
KEYWORDS: Data storage, Holography, Deep learning, Tunable filters, Phase retrieval, Education and training, Optical filters, Linear filtering, Data modeling, Signal to noise ratio
There are many ways to realize null reconstruction in polarization holography, which can be divided into two types. One is the null reconstruction without exposure response coefficient constraint, and the other is the null reconstruction limited by the exposure response coefficient. On the basis of previous studies, we have further studied these two types of null reconstruction, and obtained the necessary conditions for realizing the two types of null reconstruction under arbitrary interference angle and polarization state.
In Big Data era, holographic data storage has become a good candidate recording technology, because of there are not only large storage capacities, but also high transfer rates. However, the realized capacity of it has a big gap to the theory. Polarization holography, a newly researched field, with the extraordinary capabilities in modulating the amplitude, phase, and polarization of light have resulted in several new applications, such as holographic storage technology, multichannel polarization multiplexing, vector beams, and optical functional devices. In this paper, the fundamental research on polarization holography with linear polarized light, a component of the theory of polarization holography, has been introduced. The polarization modulation realized using these polarization characteristics exhibits unusual functionalities, rendering polarization holography as an attractive research topic in a novel method for increasing the capacity of holographic data storage has been provided.
Polarization holography has gained traction with the development of tensor theory. It primarily focuses on the interaction between polarization waves and photosensitive materials. By introducing the polarization characteristics of light into conventional holography, more degrees of freedom can be provided to control optical information. Based on the polarization modulation of polarization hologram, we propose a method to realize bifocal-polarization holographic lens in volume hologram. Two foci can be generated simultaneously or separately by changing the polarization state of the reading wave. The material used is a PQ/PMMA polarization sensitive medium, the thickness is 1.5mm. The bifocal-polarization holographic lens has 112 mm clear aperture and 446mm focal length.
The phase retrieval method based on deep learning can be used to solve the iterative problem in holographic data storage. The key of the deep learning method is to build the relationship between the phase data pages and the corresponding near-field diffraction intensity patterns. However, to build the correct relationship, thousands of samples of the training dataset are usually required. In this paper, according to the coding characteristics of phase data pages, we proposed an image segmentation method to greatly reduce the number of original training dataset. The innovation proposed by this new method lies in the special segmentation of the original samples to expand the number of samples.
The tensor polarization holography theory has predicated some phenomena and been verified by the experiments. In the theory, the parameters α and β represent the scalar and tensor coefficients of the photoinduced change in dielectric tensor respectively. The ratio of α to β, called the exposure response coefficient, is a key to manipulate the polarization state of reconstructed waves and deepen the understanding of tensor polarization holography theory. In this work, for the polarization-sensitive material, phenanthrenequinone-doped poly methyl methacrylate (PQ/PMMA), we analyze the effect of interference angle and the polarization states of signal wave on the initial exposure response coefficient when the reference wave is s-polarized in linear polarization holography.
Polarization holography based on tensor theory can accurately describe the reconstruction characteristics at arbitrary interference angles, so some optical elements such as wave plates can be produced by polarization holography. The wave plates are important optical elements that can control the phase and polarization state of wave. Conventional wave plates convert the polarization state of the incident wave through crystal birefringence and then require the accurate thickness. Based on the polarization holography described by tensor theory, we produce the half-wave plate whose azimuthal angle of fast axis may be arbitrary by using the polarization sensitive material, phenanthrenequinone-doped poly methyl methacrylate (PQ/PMMA).
KEYWORDS: Holography, Polarization, Dielectric polarization, Multiplexing, Camera shutters, Diffraction, Photonics, Dielectrics, Wavelength division multiplexing, Signal to noise ratio
The null reconstruction can be used to realize multi-channel recording, thereby improves the storage capacity. In this work, phenanthrenequinone-doped poly(methyl methacrylate) photopolymer (PQ/PMMA) that is sensitive to the polarized wave, is used as the recording medium. To better reach the null reconstruction, we need to control exposure time and intensity in the recording stage. By adopting the suitable experimental parameters, the crosstalk between the two holograms is negligible. The analysis of the experimental results shows that the ratio of optical powers of the signal wave to that of reference wave is 1:8-1:10, the exposure time is about 12 minutes, and the optimal signal-to-noise ratio can reach 21:1.
Based on tensor polarization holography, the variation of exposure response coefficient with the increase of exposure energy under different recording process is introduced in this paper. We find that different recording processes have different effects on the exposure response coefficient. However, at the beginning of exposure, there is an initial value of the exposure response coefficient independent of the holographic recording process. With this special phenomenon, polarization modulation of reconstructed wave can be easily realized at low exposure energy, such as faithful reconstruction, orthogonal reconstruction and null reconstruction.
KEYWORDS: Phase retrieval, Data storage, Holography, Fourier transforms, Computer programming, Solids, Data conversion, Reconstruction algorithms, Interferometry, Holographic data storage systems
Phase-modulation holographic data storage is imaging on the Fourier plane, and the imaging quality has a great influence on
phase retrieval. The iterative Fourier transform algorithm in the non-interference phase retrieval algorithm is widely used
because of its simple and stable system. By adding embedded data to the phase encoding method, the number of iterations can be
effectively reduced. However, the intensity of high-frequency information in Fourier intensity is weaker and more susceptible to
noise. To solve this problem, this paper proposes to use embedded data to improve the intensity of high-frequency information in
the Fourier intensity distribution, thereby improving noise immunity. In simulation, the convergence speed of BER (the bit error
rate) is faster under the same number of iterations.
The phase holographic storage system is different from the traditional object -image corresponding imaging. Because
of the particularity of phase, it is not easy to be captured by the traditional detector. Therefore, the Fourier lens is used
for Fourier transform to image it on the Fourier plane. The Fourier intensity is detected and the phase is recovered
iteratively by using the iterative Fourier transform algorithm. Due to the existence of aberrations, the wavefront phase
will be affected and the phase will be distorted.In this paper, we mainly study the influence of spherical aberration on
phase transformation. By establishing the light field with wavefront aberration, we study the influence of wavefront
aberration on phase recovery and propose the image restoration algorithm for aberration compensation .The feasibility
of the theory is proved.
Based on polarization holography theory, the plane bifocal vector lens is studied. In previous studies, the bifocal vector lens were limited to cross-angle π/2 and bulk materials. However, when the two waves are orthogonal circularly polarized state, the plane bifocal vector lens can be realized, and the limitation of cross-angle π/2 and bulk materials can be broken. The lens produces corresponding focus output through the reading wave with different polarization states, which can be used for large-area optical element research.
In polarization holography, the polarization information is recorded in the photopolymer material by interference, and the polarization state of the reconstructed wave can be calculated accurately by tensor method. Based on the guidance of tensor theory, this paper systematically analyzes the method of faithful reconstruction under any interference angle independent of exposure energy, and gives experimental verification under the condition of 40° interference angle. This conclusion is helpful to broaden our understanding of polarization holography based on tensor theory, and can be applied to the research of polarization multiplexing multi-channel holography.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.