A large viewing angle floating three-dimensional (3D) light field display based on spatial data reconstruction (SDR) algorithm is presented. It consists of the 3D light field display unit (LFDU) and the floating display unit (FDU). With the time-sequential directional backlight system, LFDU can provide 3D scenes with a large viewing angle in the horizontal direction. Based on FDU, the floating display

Computer vision plays a key role to measure the relative posture and position between the spacecrafts, especially in various important space tasks. As one of the essential steps for computer vision, camera calibration is important for obtaining precise three-dimensional contours of the space target. However, it is impossible to use the traditional calibration targets to calibrate the space camera in

We present the generation of high-quality light beams of controllable spatial shapes with uniform-intensity distribution based on diffractive optical elements (DOEs) designed by an iterative method that involves spatial Fourier filtering. The Gaussian input beam illuminates the DOEs, and after propagating certain distance transforms into desired uniform-intensity output beams with square, annular,

Radiative cooling is an energy-saving cooling technology and is achieved when the grating structure emits infrared radiant heat energy into outer space through an atmospheric window (8∼ 13μm). The radiation cooling effect is low for the simple grating structure due to its low absorptivity, thus was a novel multilayered composite grating structure proposed in the paper, an aluminum substrate composite

Chaotic optical communication is a promising technique to improve both privacy and security in communication network. This research work reports numerical investigation on optical bistability based chaos in 1.3 μm bisection, Multiple Quantum Well (MQW) laser diode. The device has longer (gain section) and shorter active regions (absorber section) with the length ratio as 97:3. In contrast to the conventional

In this study, we propose and demonstrate a dispersion compensation system for an ultrafast 25.6 Tbps waveform using multilevel 8-ary amplitude and 32-ary phase modulation. The waveform bit period was 312.5 fs, which was controlled and compensated by a 200 GHz optical frequency comb (OFC) synthesizer with a 6.4 THz bandwidth. Dispersion spectra were measured in parallel and simultaneously (within 1

The last years, FSO technologies raised interest from both scientific and commercial point of view. However, due to the optical beam propagation through the atmosphere, the signal is impaired by several phenomena like the scintillation effect, mainly because of atmospheric turbulence and imperfect misalignment between optical beam and destination terminal. In order to mitigate their negative influence

The impact of parameters based on the tracked moving flexible DOE loop for speckle suppression in laser pico-projectors was analyzed numerically. The optical scheme of the experimental setup we used is introduced, and the calculation formula of speckle contrast is briefly described. The simulation results show the acceptable tolerance range of DOE structure parameters (including the inclination angle

We study the dynamics of two interacting two-level systems (qubits) having one of them isolated and the other coupled to a single mode electromagnetic field in a thermal state. The field will play the role of a small environment, in contrast to the usual approach of modeling an environment via a thermal reservoir with many degrees of freedom. We find the analytical solution of the proposed model, which

A novel dimeric arrangement consisting of two spherical nanocrescents with tips pointing at each other in nanometer proximities is proposed. Hybridization of the plasmonic modes in close proximities leads to a 48% enhancement in Purcell factor inside the gap compared to the single spherical nanocrescent. A nanometer resolved tomographic cathodoluminescence (CL) spectroscopy combined with radiative

In the study, we investigate the generation of optofluidic laser in stable planar-concave Fabry–Pérot (FP) microcavities. The concave mirror is created on the end-facet of a fiber using the method of CO2 laser ablation and subsequent coating with dielectric layers. Coumarin 6 in ethanol is used as the gain solution to test the FP microcavities. For comparison, we first test the laser generation in

Phase fluctuations of vortex beams are examined using the random phase screen setup. By taking Gaussian, Bessel Gaussian and Laguerre Gaussian vortex beams, with the main focus being on Gaussian vortex beam, we investigate the phase fluctuations in a region around on-axis. These phase fluctuations are quantified in terms of phase variance and phase structure function. Variations of phase fluctuations

Wavefront sensorless (WFSless) adaptive optics (AO) systems have been widely studied in recent years. However, most of the existing WFSless AO systems require point sources for wavefront sensing. Aimed to correct the turbulence-degraded imaging of extended objects, this document proposes a fast wavefront correction approach for a WFSless AO system based on linear phase diversity (PD) technique. By

A simple scheme to generate a frequency and bandwidth-doubling dual-chirp microwave waveform based on a dual-polarization Mach–Zehnder modulator (DPol-MZM) is presented, and the influence of fiber chromatic dispersion during transmission is analyzed in detail. In this scheme, the lightwave is split into two beams in the DPol-MZM, and one beam is modulated via sub-MZM1 by the RF signal to generate two

This paper presents an iodine ions fluorescence quenching sensor based on hydrogel fiber doped with fluorescein. The hydrogel fiber was made by photo-crosslinking with core-cladding structure made from PEGDA precursor solutions with different concentration. Compared with calcium alginate cladding material, this structure is less susceptible to damage and the thickness of the cladding is controllable

In this paper, we propose a theoretical model based on quantitative dispersion value to evaluate the influence of loss and transmission coefficient on the flatness of the interleaver. We use dispersion range (the difference between the maximum and the minimum) as the measure of flatness, and when the dispersion range is 0.352, the flatness of the interleaver is the highest. We can control the dispersion

We investigate the few-photon absorption and emission in the laser-assisted single photoionization of hydrogen (H) atom. The results show that the electron wave ionized by the ultraviolet (UV) field can absorb or emit more than one infrared (IR) field photon. With the IR photon increases, the intensity of corresponding photoionization peak is getting weak and the distribution of them in time gets narrower

We demonstrate metal oxides CuCrO2 exhibit considerable nonlinear saturable absorption property in the near-infrared region, and fabricate typical saturable absorber (SA) by wrapping the CuCrO2 nanoparticles(NPs) into a sodium carboxymethylcellulose (NaCMC) film or polyimide (PI) film separately. These SA films could keep stable exposed to air condition for several months. In the CuCrO2-NaCMC (CuCrO2-PI)

Despite the virtues of Jones and Mueller formalisms for the representation of the polarimetric properties, for some purposes in both Optics and SAR Polarimetry, the concept of coherency vector associated with a nondepolarizing medium has proven to be an useful mathematical structure that inherits certain symmetries underlying the nature of linear polarimetric transformations of the states of polarization

In this work, high-power (peak power of more than 1 MW) UV lasing on D’–A’ transitions of interhalogen BrF* molecules (354.5 nm) is reported for the first time. To increase laser energy, Br2 molecule was first proposed as bromine donor in gas mixture of He:NF3:Br2. In this paper, the results of experimental studies of energy, spectral, temporal and spatial BrF-laser characteristics depending on excitation

Plasmonic color filters (PCFs) with subwavelength nanometallic structures have irreplaceable advantages over traditional organic dye color filters due to their unique characteristics. However, most PCFs excite weak resonances and show low selectivity, which will limit their accuracy and further applications. In this paper, we introduce a PCF design utilizing tapered annular aperture arrays, which not

In this paper, a novel and relatively simple scheme for generation of high-quality 16QAM-modulated multi-carrier vector millimeter-wave (mm-wave) was proposed, which was only based on a single Mach–Zehnder modulator (MZM), while the precoding technique and optical filter were not needed. At the transmitter, electrical dual single sideband (SSB) signals were generated by a digital signal processing

In this paper, we propose a statistical adaptive derivative equalizer (SADE) in order to reduce an optical beat interference (OBI) noise in an optical access link. The proposed SADE generates an output signal similar to the shape of the input pulse amplitude modulation (PAM)-4 signal waveform, which is implemented as an adaptive total variation that responds to the shape of the multi-step signal waveform

It is known that an axicon forms an aberrated Bessel beam when the input light is incident at an oblique angle, and the aberration can be removed by adding ellipticity to the axicon. The present work shows that the approach does not recover the Bessel beam along its entire depth of field when an additional tilted optical window is present in the beam path. This situation is increasingly common in advanced

In this paper, a filterless reconfigurable frequency mixer based on a wideband photonic microwave phase shifter is proposed. The main device is a single PDM-DPMZM which is applied to generate a pair of orthogonally polarized CS-SSB signals. A pair of PCs are followed to introduce a tunable phase to the CS-SSB signals. By changing the detection scheme of the output optical signals and tuning the PCs

The spin Hall effect of light (SHEL) is a photonic version of the spin Hall effect in electronic systems, and it has been a focused research area in the recent ten years. However, due to the lack of effective methods dynamic modulation of spin-dependent splitting, the practical application of SHEL has remained a challenge, still urgently waiting to be resolved. In recent years, SHEL has been applied

In this work, we investigate a LUT-based digital predistortion technique applied to a Visible Light Communication system. We study the performance of the predistortion technique for OFDM signals with up to 2048 subcarriers, 16-QAM modulation, and three levels of DC bias considering the voltage–current LED response of a commercially available device. In addition, we propose a new and simpler pilot-assisted

Underwater optical wireless communication has attracted widespread attention due to its high bandwidth. The complex compositions of seawater affect the transmission of underwater optical signals. However, for underwater optical wireless channel modeling, the turbulence effect cannot be integrated into the Monte Carlo simulation framework for absorption and scattering. Based on the generalized Snell’s

Fringe projection profilometry based on phase-shift method has been commonly used for three-dimensional measurement. However, measuring the specular surface is always a challenging task since the specular area cannot present original intensity information. This paper presents a novel framework for measuring objects with specular surfaces. Firstly, a set of phase-shifted fringe patterns with maximum

Cold atoms and polar molecules have long been candidates for the implementation of quantum information processing. Although many schemes of two-dimensional (2D) moving optical or magnetic lattices have been proposed for atomic shift register, little work has been done on 2D electric lattice for molecular shift register, mainly due to the complexity of molecular energy level structures as well as the

This work reports mechanically exfoliated indium tin oxide (ITO) as saturable absorber (SA) for Q-switched operation in fiber lasers. The ITO is mechanically exfoliated from 99.99% pure In2O3/SnO2. As ITO has a broad operational wavelength from visible to infrared, indium tin oxide saturable absorber (ITO-SA) is incorporated into ytterbium-doped fiber laser (YDFL) and erbium-doped fiber laser (EDFL)

The performance evaluations and enhancements of wavelength-division-multiplexing (WDM) for the free-space optical (FSO) communication systems using a digital pulse-position modulation (DPPM), M-ary pulse-position modulation (M-ary PPM), and on-off keying (OOK) are investigated in this paper. In the WDM/DPPM-FSO communication systems, WDM channels suffer from the inter-channel crosstalk (ICC) while

Here, a novel graphene-based square ring resonator is proposed to design 2-channel and 4-channel demultiplexer. Compared to typical ones, graphene demultiplexers are a better performer and recently considered as a highly promising candidate for low footprint and minimum crosstalk purposes. By introducing such a unique gradient, the plasmon resonances of the demultiplexer are directly excited and resonant

Behavior of the step-index plastic optical fibers (SI POFs) is examined in a straight-curved configuration for various launching conditions and fiber curvature. This was achieved by applying the power flow equation to calculate the power distribution at the end of the straight fiber segment that precedes the curved one, allowing calculation of the power loss for the latter. We have shown that a small

We demonstrate efficient random lasing from microslices containing dye-doped colloidal silica nanoparticles. The nanoparticles with diameters of 20 nm were synthesized by a modified Stöber method, having a high emission efficiency and well dispersed in an aqueous medium. From the suspension of the nanoparticles, a film is created via self-assembly of colloidal nanoparticles. After grinding the film

Mueller polarimetric imaging is considered a potentially powerful technique for probing the microstructural information in the biomedical field. In this study, the Mueller matrix microscopy was adopted to characterize the microstructures of breast cancer cells exhibiting different receptor proteins expressions. To be specific, four types of breast cancer cells were selected, and a suitable method was

In this paper, we present a cascaded system, with optical intensity chaos and electro-optic phase chaos, to allow for bidirectional communication. In this scheme, we utilize the intensity chaotic signal instead of the traditional continuous wave (CW) to inject into the electro-optic oscillator to produce a phase chaotic signal. Under a suitable feedback intensity, we also demonstrate that the configuration

We have analyzed and discussed a flat-top Brewster filter that works in full conical mounting. Results reveal that flat-top reflection band can be formed by merging double peaks that corresponded to guided modes with different polarization states. Merging is achieved by adjusting the incident angle in the design. When the proposed single-layer waveguide grating structure is irradiated with transverse

The intent of this paper is to design of a nanoantenna with Fano response, by using a split ring resonator (SRR) element as a refractive index sensor in the range of 2 – 4μm for the infrared spectrum. A few organic material particles are implanted inside of the gaps which are made by the gold layers so that using organic materials conduce to the switchable characteristic in this nanoantenna. The gaps

In structural health monitoring, vibrations often behave as non-Gaussian process, such as gear and engine failure. In this paper, a high-order cumulants algorithm-based phase-sensitive optical time-domain reflectometry is proposed to detect and analyze non-Gaussian vibration. When disturbances with non-Gaussian probability distribution are applied on the sensing fiber, the probability distribution

This paper analyzes the physical layer secrecy (PLS) performance of a hybrid free space optical and radio frequency (FSO/RF) communication system under a modified selection combining scheme. The transmission scheme takes into account secrecy performance as well as diversity gain and ease of implementation. The effects of FSO link, namely the FSO atmospheric turbulence and the FSO receiver pointing

In this paper, power domain non-orthogonal multiple access (NOMA) is introduced in underwater visible light communication (UVLC) to improve the spectrum efficiency and the sum transmission rate. A NOMA-UVLC system employing two LEDs with different colors is designed to improve the propagation efficiency, by bearing different information on different carriers. We experimentally investigate the BER performance

For the direct modulation of a laser using frequency division multiplexed (FDM) channels, an iterative procedure is presented for power loading based on the signal-to-noise-and-distortion ratio. The power of nonlinear distortion arising from the modulation dynamics of the laser and dispersive transmission combined with direct detection is estimated using a two-tone test with the power being determined

We theoretically investigate the conditions of achieving phase-preserving amplitude regeneration for the universal nonlinear optical loop mirror (NOLM) structure and present a method of determining the optimal working point for amplitude shaping. A normalized amplitude-phase transfer parameter is introduced to measure the phase-preserving performance at the working points of multilevel regeneration

Non-contact, noninvasive techniques to control the orientation of single living cells are highly valuable for biological research and clinical applications. We experimentally demonstrate a single-beam, single-fiber optical manipulation technique using an anisotropic, four-lobed light field propagated by low-order fiber mode LP21. The laser beam forms a rotationally non-axisymmetric optical multi-trap

In this work, we introduce a new class of light beam, the circular symmetric Airy beam (CSAB), which arises from the extensions of the one dimensional (1D) spectrum of Airy beam from rectangular coordinates to cylindrical ones. The CSAB propagates at initial stages with a single central lobe that autofocuses and then defocuses into the multi-ring structure. Then, these multi-ring perform the outward

Circular polarization shift-keying (CPolSK) modulation is crucial for optical communication in free space optical communication. In this paper, we propose a new optical communication system with multiple orbital angular momentum (OAM) modes for division multiplexing CPolSK modulation signals. A well-designed reference beam is employed to interfere with the CPolSK-OAM-division multiplexing (CPolSK-OAM-DM)

Quantifying the microcirculation system is helpful for a more accurate diagnosis of blood flow related diseases. In this work, we report a depth-resolved fractal parameter analysis of human microvasculature obtained with a swept-source optical coherence tomography (SS-OCT) system after depth compensation. In our analysis, the characteristics of Gaussian optics and the attenuation of light intensity

A new and simple scheme of generating millimeter-wave (mm-wave) signal with dispersion tolerance and multi frequency operation is proposed and experimentally demonstrated, which is based on a single polarization multiplexing binary phase-shift keying (BPSK) modulator. In our scheme, a sub-modulator on one branch of the modulator is worked at its quadrature transmission point (QTP) and driven by a clock

We numerically investigate a waveguide of metal pillar arrays (MPAs) and a hybrid waveguide consisting of the MPAs and a dielectric film in 0.1-1.0 THz. The numerical results show two resonance modes with a bandgap of 0.14 THz are supported in MPAs. The propagation loss and field confinement can be modified by the addition of a low loss dielectric film by tuning the film thickness and the refractive

Accurately characterizing the inner surface of monocapillary X-ray optics is important because the deformation of the inner wall is the greatest limitation on the quality of monocapillaries. Here, a contrast-enhanced microscopic computed tomography (micro-CT) technology was applied to measure the monocapillary. The 50 nm lead powder was used to fill the hollow part of a parabolic monocapillary X-ray

We propose and experimentally demonstrate a 2.333-Tbit/s bi-directional optical mobile network using optical wireless communication (OWC). The proposed network architecture is divided into: fronthaul network connecting between the distributed-unit (DU) and the remote-radio-unit (RRU); and midhaul network connecting between the central unit (CU) and the DU. At the midhaul, an aggregated 2.333-Tbit/s

In this letter, a hollow core ring based circular photonic crystal fiber (PCF) is explored and proposed with stably supporting terahertz (THz) orbital angular momentum (OAM) states transmission. The proposed PCF is discussed, investigated, analyzed and simulated with optical properties in a terahertz frequency spectrum ranging from 0.20 THz to 0.55 THz. The OAM and THz communication-based parameters

In this research work, mixed radio frequency (RF)/free space optical (FSO) communication systems have been investigated in the presence of multiple interferers at the relay node. The considered system incorporates partial relay selection (PRS) using the available outdated channel state information (CSI) at the relay node to combat the effect of interference. The fading on the PRS-aided RF link has

In the current study, for the first time, we numerically investigate the optical properties of fixed surface area Sierpinski triangles and Sierpinski carpets. We solve the two dimensional Schrödinger equation by using three-point centered difference method in the Cartesian coordinate. By using the proposed Sierpinski systems, wave function engineering is now possible. We illustrate the wave function

We propose a cross-phase modulation (XPM) mitigation method in wavelength division multiplexing (WDM) systems, which is enabled by the split nonlinearity compensation (NLC) and the modified decision directed recursive least square (DD-RLS) based nonlinear phase noise (NLPN) tracking algorithm. In the proposed method, the split NLC reduces the interaction between the dispersion and the XPM and makes

In visible light communication (VLC) under weak illuminance, the single-photon avalanche diode (SPAD) is usually utilized for signal detection due to its high sensitivity to optical signals. However, the SPAD detector suffers from the nonlinearity effect induced by the dead time, which degrades the performance of the classical constellation and signal detection schemes. In this paper, in consideration

Phase modulation depth (C) and carrier phase delay (θ) are two critical factors for the phase generated carrier (PGC) demodulation scheme. Traditional PGC demodulation schemes require θ be mπ (m=0, ±1, …) and C be specified values, otherwise, the demodulated signal will be distorted. In this paper, a PGC-DCDM demodulation scheme insensitive to C and θ is proposed. Perform the differential-cross-di

In this article, the peak-power expression of dissipative-soliton-resonance (DSR) pulse is derived, in a normal-dispersion fiber laser, by using the equation for the resonance curve and the relationship between the parameters of cubic–quintic complex Ginzburg–Landau (CGLQ) equation and the cavity parameters. According to the peak-power expression, the peak power of DSR pulses is inversely proportional