optical data processing has significant potential in future aerospace systems. Potential system applications are identified. One of the more important applications is the determination of errors of large antenna or re...
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optical data processing has significant potential in future aerospace systems. Potential system applications are identified. One of the more important applications is the determination of errors of large antenna or reflector surface and the active control or compensation of the surface. Technological challenges to the application of optical data processing technology to aerospace systems are identified, and current NASA research efforts are discussed.
Kinoforms are experimental, computergenerated, optical elements which have potential for data input operations in biomedical image processing applications. Much development work lies ahead, but the user of holographic...
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Maintaining custody of Resident Space Objects (RSOs) is of particular importance to the Space Situational Awareness (SSA) community. Custody can be lost when data providers are unaware of changes in RSO dynamics. Rece...
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Fiber-optic communication systems are nowadays facing serious challenges due to the fast growing demand on capacity from various new applications and services. It is now well recognized that nonlinear effects limit th...
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Fiber-optic communication systems are nowadays facing serious challenges due to the fast growing demand on capacity from various new applications and services. It is now well recognized that nonlinear effects limit the spectral efficiency and transmission reach of modern fiber-optic communications. Nonlinearity compensation is therefore widely believed to be of paramount importance for increasing the capacity of future optical networks. Recently, there has been steadily growing interest in the application of a powerful mathematical tool-the nonlinear Fourier transform (NFT)-in the development of fundamentally novel nonlinearity mitigation tools for fiber-optic channels. It has been recognized that, within this paradigm, the nonlinear crosstalk due to the Kerr effect is effectively absent, and fiber nonlinearity due to the Kerr effect can enter as a constructive element rather than a degrading factor. The novelty and the mathematical complexity of the NFT, the versatility of the proposed system designs, and the lack of a unified vision of an optimal NFT-type communication system, however, constitute significant difficulties for communication researchers. In this paper, we therefore survey the existing approaches in a common framework and review the progress in this area with a focus on practical implementation aspects. First, an overview of existing key algorithms for the efficacious computation of the direct and inverse NFT is given, and the issues of accuracy and numerical complexity are elucidated. We then describe different approaches for the utilization of the NFT in practical transmission schemes. After that we discuss the differences, advantages, and challenges of various recently emerged system designs employing the NFT, as well as the spectral efficiency estimates available up-to-date. With many practical implementation aspects still being open, our mini-review is aimed at helping researchers assess the perspectives, understand the bottlenecks, and envision
While single wavelength all-optical information encoding through optically induced orientation of azobenzene dyes is being extensively pursued, we propose multi-wavelength optical data processing and recording based o...
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While single wavelength all-optical information encoding through optically induced orientation of azobenzene dyes is being extensively pursued, we propose multi-wavelength optical data processing and recording based on disperse red 1 (DR1) and 4-(4-hydroxybutyloxy) azobenzene doped organic-inorganic hybrid films to increase the density of recording data. By investigating the change of absorbance spectrum of the doped film under different irradiations, results indicate a laser pulses around 470 nm would be suitable as the probe beam. In the measurement of optical data processing and recording, two cw lasers pulse at 532 nm and 355 nm induce trans-cis isomerization of the azo-dyes in the film, while the output of the probe beam record the processed data as {(-1), (0), (1)} according to different inputs of the pump beams. Since the light induced isomerization has a sensitive response in the as-prepared solid organic-inorganic matrix system, the films is promising as recording and monitoring element in all-optical devices over a wide range of repetition rates. (C) 2018 optical Society of America under the terms of the OSA Open Access Publishing Agreement
Recent advances in the density and complexity of photonic integrated circuits have facilitated possible implementation of chip-scale optical communication systems. Chip-scale optical interconnects and opticaldata pro...
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Recent advances in the density and complexity of photonic integrated circuits have facilitated possible implementation of chip-scale optical communication systems. Chip-scale optical interconnects and optical data processing are two important functions to transmit and process signal in the optical domain. Silicon photonics offers a promising platform to enable chip-scale optical interconnects and optical data processing using silicon photonic devices. In this paper, we review our recent progress in the design, modeling, and fabrication of silicon photonic devices and their applications in chip-scale optical interconnects and optical data processing with advanced modulation formats. For chip-scale optical interconnects, we experimentally demonstrate digital signal transmissions in silicon microring and silicon vertical slot waveguide. Terabit chip-scale optical interconnect is demonstrated in the experiment. Also, we experimentally demonstrate analog signal transmissions in silicon microring and silicon photonic crystal nanocavity. For chip-scale optical data processing, we experimentally demonstrate all-optical wavelength conversion using a silicon waveguide, simultaneous polarization and wavelength demultiplexing using 2D grating coupler connected with microrings, two-mode (de)multiplexing using a tapered asymmetrical grating-assisted contra-directional coupler, and two-/three-mode (de)multiplexing using asymmetrical directional converter. In addition, we propose and simulate chip-scale opticaldata exchange, chip-scale high-base optical computing, and chip-scale optical coding/decoding by using nonlinear interactions in a silicon-organic hybrid slot waveguide. The obtained theoretical and experimental results of chip-scale optical interconnects and optical data processing indicate possible integration of optical communication functions on a monolithic chip.
PLZT-7/65/35 is a ferroelectric ceramic with strong electrooptic properties and memory; it is switched through transparent electrodes when mechanically strained. Matrix addressed x-y page composers for interfacing ele...
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PLZT-7/65/35 is a ferroelectric ceramic with strong electrooptic properties and memory; it is switched through transparent electrodes when mechanically strained. Matrix addressed x-y page composers for interfacing electrical and coherent optical systems are being fabricated with PLZT. Switching voltages are 50–300 V. optical efficiencies greater than 40% have been achieved. Strains near 2.4 × 10?3 mm/mm permit half-wave retardation switching in 100-μ-thick plates with 80-V read-in and 190-V erase levels (60 Hz hysteresis data). A 128 × 128 element array can operate at 107 bits/sec with 10-μsec switching in a row at a time mode. Half-select disturbances affect contrasts. Applications in displays are also feasible.
The nonlinear Fourier transform (NFT) is an approach that is similar to a conventional Fourier transform. In particular, NFT allows to analyze the structure of a signal governed by the nonlinear Schr & ouml;dinger...
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The nonlinear Fourier transform (NFT) is an approach that is similar to a conventional Fourier transform. In particular, NFT allows to analyze the structure of a signal governed by the nonlinear Schr & ouml;dinger equation (NLSE). Recently, NFT applied to NLSE has attracted special attention in applications of fiber-optic communication. Improving the speed and accuracy of the NFT algorithms remains an urgent problem in optics. We present an approach that allows to find all variants of symmetric exponential splitting schemes suitable for the fast NFT (FNFT) algorithms with low complexity. One of the obtained schemes showed good numerical results in computing the continuous spectrum compared with other fast fourth -order NFT schemes. (c) 2024 Optica Publishing Group
In this paper, we consider the properties of the nonsymmetrical Fourier transformation which is space-variant in both rectangular and polar coordinates. A coherent optical processor composed of two nonsymmetrical Four...
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In this paper, we consider the properties of the nonsymmetrical Fourier transformation which is space-variant in both rectangular and polar coordinates. A coherent optical processor composed of two nonsymmetrical Fourier transformers is introduced. This processor allows rotation-variant linear filtering operations and matched filtering. Two configurations for such a processor are proposed. For certain parameters of both nonsymmetrical Fourier transformers it is possible to obtain a space-invariant processor with both lateral magnifications equal to unity. However, introducing any filter operation results in a rotation-variant performance.
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