Hybrid Optical System Research Articles

Revolutionizing superhighway traffic board lighting with remote LED spotlights

In this paper, we present a groundbreaking approach to enhance the illumination of traffic boards along superhighways, addressing significant challenges associated with conventional lighting systems. Our innovative method revolves around the strategic placement of remote spotlights at the side of the roadway to illuminate traffic signs equipped with retroreflector film (RTRF). The essence of our approach lies in remote illumination, which requires meticulous adjustment of the divergence angle of the spotlights to match the size of the signs and their distance from the projection source. To achieve the desired spotlight configuration, we have developed a hybrid optical system that incorporates a paraboloid reflector and a lens mounted on a bridge holder situated on top of the mirror. Through spot light illumination, we discovered that the initial divergence angle of the RTRF was too narrow. To improve projection angle tolerance, we recommend attaching a light diffuser film onto the surface of the RTRF. The coverage area ratio of the diffuser film can be adjusted to select the desired divergence angle for the reflected light. Our experimental measurements have yielded significant results, showcasing the half-divergent angle of the RTRF ranging from 3° to 7° for different coverage area ratios of the diffuser. In practical terms, with a target luminance of 300 nits at the white word on the traffic board, the power consumption of the spotlight fixture of the roadway was only 40 W, representing over 75% power savings when compared to traditional lighting methods. Consequently, our approach opts to utilize spotlights for illuminating specific traffic boards on superhighways, offering a more efficient and manageable lighting solution that greatly benefits both motorists and road maintenance personnel.

Enhancing network security with hybrid feedback systems in chaotic optical communication

This paper presents a pioneering approach to bolstering network security and privacy by implementing chaotic optical communication with a hybrid optical feedback system (HOFS). The current baseline methods in network security are often less feasible for hybrid feedback systems, including limited robustness, compromised security, and synchronization challenges. Therefore, this paper proposes a hybrid approach to address these shortcomings by integrating the HOFS into chaotic optical communication systems (HOFS-COCS) to overcome the baseline challenges. This paper aims to improve network security while significantly maintaining efficient communication channels. Moreover, We designed two algorithms, one for chaotic maps generation and another for text encryption and decryption, to improve security in the hybrid feedback system. Our findings demonstrate through rigorous experimentation and analysis that the proposed (HOFS-COCS) method significantly improves network security by enabling reliable chaos generation, synchronization, and secure message transmission in chaotic optical communication systems. This research represents a significant advancement towards enhanced secrecy and synchronization in chaotic optical communication systems, promising a paradigm shift in network security protocols.

In vivo optical assessment of cerebral and skeletal muscle microvascular response to phenylephrine.

This study aimed to investigate the simultaneous response of the cerebral and skeletal muscle microvasculature to the same phenylephrine (PE) boluses. A hybrid optical system that combines hyperspectral near-infrared spectroscopy (hs-NIRS) and diffuse correlation spectroscopy (DCS) was used to monitor changes in tissue oxygenation and perfusion. Data were collected from the head and hind limb of seven male Sprague-Dawley rats while administering intravenous (IV) injections of PE or saline to all animals. The response to saline was used as a control. Skeletal muscle oxygenation decreased significantly after PE injection, while a statistically underpowered decrease in perfusion was observed, followed by an increase beyond baseline. Vascular conductance also decreased in the muscle reflecting the drug's vasoconstrictive effects. Tissue oxygenation and perfusion increased in the brain in response to PE. Initially, there was a sharp increase in cerebral perfusion but no changes in cerebral vascular conductance. Subsequently, cerebral flow and vascular conductance decreased significantly below baseline, likely reflecting autoregulatory mechanisms to manage the excess flow. Further, fitting an exponential function to the secondary decrease in cerebral perfusion and increase in muscular blood flow revealed a quicker kinetic response in the brain to adjust blood flow. In the skeletal muscle, PE caused a transient decrease in blood volume due to vasoconstriction, which resulted in an overall decrease in hemoglobin content and tissue oxygen saturation. Since PE does not directly affect cerebral vessels, this peripheral vasoconstriction shunted blood into the brain, resulting in an initial increase in oxygenated hemoglobin and oxygen saturation.

On the performance of a hybrid optical communication system: MGDM–FSO for challenging environments

On the performance of a hybrid optical communication system: MGDM–FSO for challenging environments

Design and implementation of a lightweight hybrid optical system for aircraft head-up display

Design and implementation of a lightweight hybrid optical system for aircraft head-up display

Robust stabilization of fractional-order hybrid optical system using a single-input TS-fuzzy sliding mode control strategy with input nonlinearities

<p>Hybrid optical systems with integrated control mechanisms enable a dynamic adjustment of optical components, ensuring real-time optimization, adaptability to changing conditions, and precise functionality. This control requirement enhances their performance in applications demanding responsiveness, such as autonomous systems, adaptive optics, and advanced imaging technologies. This research introduces a novel approach, employing a dynamic-free Takagi-Sugeno fuzzy sliding mode control (TS-fuzzy SMC) technique, to regulate and stabilize a specific category of chaotic fractional-order modified hybrid optical systems. The method addresses uncertainties and input-saturation challenges within the system. Leveraging a novel fractional calculus definition along with the non-integer type of the Lyapunov stability theorem and linear matrix inequality principle, the TS-fuzzy SMC approach was applied to effectively mitigate and regulate the undesired behavior of the fractional-order chaotic-modified hybrid optical system. Notably, this scheme achieved control without experiencing undesirable chattering phenomena. The paper concludes by offering concrete examples and comparisons, demonstrating how the theoretical findings are applied in real-world scenarios. This provides practical insights into the effectiveness of the proposed approach in diverse applications.</p>

Multi-channel quantum noise suppression and phase-sensitive modulation in a hybrid optical resonant cavity system

Multi-channel quantum noise suppression and phase-sensitive modulation in a hybrid optical resonant cavity system

A New Secure Communications Scheme Based on a Synchronisation of Hybrid Chaotic System

This paper presents a novel approach for secure communication utilizing a chaotic hybrid optical bistable system and chaotic modulation. The proposed crypto system encrypts the message at the transmitter using the chaotic hybrid optical bistable system with decorrelation operation to improve the chaotic sequence's performance. The encoded message is then injected into the dynamics of the chaotic memristor system. At the receiver, the synchronization of the two chaotic systems with passive control and predictive control allows for the recovery of the message through chaotic demodulation. The effectiveness of this approach is demonstrated through numerical simulation using medical images.

Hybrid Optical and Thermal Energy Conversion System to Power Internet of Things Nodes

This article presents research about a hybrid power system dedicated to Internet of Things (IoT) nodes. As an introduction, performance tests of the harvesters, that is, a 40 × 40 mm Peltier cell based on Bi2Te3 and three solar cells, monocrystalline, polycrystalline, and amorphous, are presented. The study established the dependence of the effect of generated power on the load resistance. Thus, it states how the internal resistance of the harvesters changes. Following the above tests, a complete power unit with a single harvester and an LTC3108 conversion circuit, as well as an energy buffer in the form of a 1 mF supercapacitor, were built and tested. The unit with a thermoelectric generator generated power from 14 to 409 µW. The unit with a 65 × 65 mm polycrystalline cell generated power from 150 to 409 µW. Next, a hybrid system was built and tested with both of the aforementioned harvesters, which generated power from 205 to 450 µW at 2000 lx illumination and a temperature difference of 20 °C for the thermoelectric generator claddings.

Investigation of Optical Cavity Dynamics with Raman and Ytterbium-Doped Gain Media Integration

This study delves into a comprehensive examination of an optical cavity system that integrates Raman and Yb-doped gain media, with a focus on understanding their interactions. The research implies a characterization of each gain medium within the cavity while subjecting them to diverse co-pumping conditions with the other. When the Raman-lasing cavity is co-pumped by exciting the Yb-doped section, the resulting composite laser exhibits significant threshold reductions and there is an optimal co-pumping regime that enhances energy transfer from pump to Stokes. As for the complementary cavity, where the Yb-doped gain is influenced by the co-pumped Raman gain, at moderate pump powers a light-controlling-light behavior phenomenon arises. Within this regime, the 1064 nm signal suppresses the Yb-generated 1115 nm signal, suggesting potential applications in intracavity optical modulation. For higher pump levels, a cooperative effect emerges whereby both lasers mutually enhance each other. Minor variations in the primary 974 nm pump power, even by just a few milliwatts, result in significant capabilities for switching or modulating the Stokes signal. Under these conditions of mutual enhancement, the hybrid optical system validates notable improvements regarding energy transfer efficiency and threshold reduction. This research provides valuable insights into the intricate dynamics of optical cavity systems and reveals promising avenues for applications in advanced optical modulation technologies.

Raman/EDFA Hybrid System to Enhance the Optical Signal in the Optical Network

In this paper, a hybrid optical signal amplification system that includes Raman scattering and Erbium-doped fiber amplifier (EDFA) was simulated to take advantage of the amplification properties of the optical signal transmitted through the optical fiber network that connects the first and third campuses of the University of Mosul. The two types of optical signal amplifiers were studied individually and together, and the effect was observed in each case on the optical signal parameters such as the Q-factor, noise figure, signal-to-noise ratio, and gain. Optisystem ver.7.0 software was used to simulate the proposed system. The results showed that the Raman scattering and EDFA hybrid systems functioned effectively. The output signal power level is higher than the input signal power level that increased from (16 microwatts) to (83 mill watts). For each frequency, the gain is positive and the noise figure is relatively high. Although, this indicates that some noise introduced into the system. The output signal to noise ratio (OSNR) is high (55 dB). Moreover, the system is still able to maintain a high signal-to-noise ratio. The obtained results showed that the Raman scattering and EDFA hybrid system is a worthwhile technique for amplifying optical signals for the optical network connecting the first and third campuses of the University of Mosul.

Research on a hybrid optical storage control strategy based on a DC virtual synchronous generator and MPC

There are many problems in optical storage systems, including fault ride-through and disturbance, inadequate DC bus voltage support, and high state variable overshoot. The main problem is caused by the slow dynamic reaction speed of the energy storage system based on traditional PI control to the DC voltage of the optical storage system. A hybrid optical storage system control optimization strategy based on a DC virtual synchronous machines and improved model predictive control (MPC) was proposed in the paper as a solution to the aforementioned issues. A strategy based on DC virtual synchronous generator can improve the damping braces and overshoot suppression of DC voltage fluctuation during the disruption process of the energy storage system in the optical storage system. The dynamic response speed of energy storage in optical storage systems may be further increased based on the improved MPC. The effectiveness and validity of the control strategy proposed in the paper were verified by the simulation examples.

Development of Unified Hybrid WDM-PON With Spectrally Hidden Data Channel System and FBG Optical Sensor Network

Abstract As the demand for fiber optical data transmission systems and other type of applications, which require optical media, like optical sensing increases, the unauthorized parties are becoming increasingly interested in such systems. Also, with such demand, more complex optical systems are required; thus, the network infrastructure is becoming more crowded. It is vital to economize on the available resources and infrastructure to ensure the needs of all interested business, governmental or end-user sides. Therefore, the present research focuses on the development of a unified hybrid optical system. The developed hybrid optical transmission system adds additional protection to the channels, allows for the unification of standard optical data transmission channels, optical sensors and spectrally hidden data transmission channel systems, and increases the efficiency of the optical components used.

Depth error correction for plenoptic cameras based on an innovative AR system combining geometrical waveguide and micro-lens array

Plenoptic cameras have been increasingly applied in three-dimensional (3D) optical imaging and measurements. Micro-lens array is the key component to capture the images at different depths simultaneously to realize the 3D reconstruction of the scenery. However, only a part of the captured information will be used eventually when focusing on specific objects, which implies a waste of time and resources that are incompetent for fast-response tasks like gesture recognition. Furthermore, it is still quite challenging to accurately calibrate the depths under complex circumstances, even sometimes losing a part of the target information due to the low signal-to-noise ratio. In this paper, a new hybrid optical system is developed combining a geometrical waveguide and micro-lens array to project a virtual scale network for quantitative depth calibration and fast-tracking of targets. Such a methodology based on the augmented reality (AR) mechanism helps to rapidly scope the targeted objects/features without reconstructing the full range model, significantly saving the processing time for a low-latency response. By establishing a geometrical model to quantitatively correlate the images in the auxiliary coordinate system and the virtual scale coordinate system, the depth error caused by the plenoptic camera can be calibrated and corrected. The coefficient of determination R2is used to evaluate the depth accuracy of 3D images and acts as the threshold to control the depth correction iterations. The closer the value of R2 is to 1, the more accurate the depth information is. Experiments proved that even under complex backgrounds or insufficient light, in virtue of the virtual coordinate networks, backgrounds could be rapidly filtered, and targets were effectively identified with accurate depth information. The algorithm flow chart for the correction of depth error is given. In such a way, the system can achieve faster and more accurate capturing of 3D objects in a real-time manner than conventional plenoptic cameras.

Design and simulation of optical chaotic-based secure hybrid optical communication system

Design and simulation of optical chaotic-based secure hybrid optical communication system

Three-dimensionally reconfigurable focusing of laser by mechanically tunable metalens doublet with built-in holograms for alignment

Abstract Metalenses have potential to replace various bulky conventional optical elements with ultrathin nanostructure arrays. In particular, active metalenses with reconfigurable focusing capability have attracted considerable interest from the academic and industrial communities. However, their tuning range is currently restricted by limited material properties and fabrication difficulties. Here, a hybrid optical system capable of three-dimensional relocation of a focal spot is proposed and experimentally demonstrated. The system comprises a mechanically actuated passive metalens doublet that can be easily fabricated with commonly available materials and processes. An incident laser can be focused to a desired point in three-dimensional space simply by rotating two metalenses or changing their separation. In addition, exploiting the polarization-multiplexing capability of metasurfaces, a hologram is incorporated to the metalenses to guide rotational and positional alignment of two metasurfaces. The ease of fabrication and alignment provided by this approach could widen its application to many practical fields.

Computational Imaging in Dual-Band Infrared Hybrid Optical System with Wide Temperature Range.

The special dispersion and temperature characteristics of diffractive optical element (DOE) make them widely used in optical systems that require both athermalization and achromatic aberrations designs. The multi-layer DOE (MLDOE) can improve the diffraction efficiency of the overall broad waveband, but its diffraction efficiency decreases with changes in ambient temperature. When the ambient temperature changes, the micro-structure heights of MLDOE and the refractive index of the substrate materials change, ultimately affecting its diffraction efficiency, and, further, the optical transform function (OTF). In this paper, the influence of ambient temperature on the diffraction efficiency of MLDOE in a dual-infrared waveband is proposed and discussed, the diffraction efficiency of MLDOE caused by ambient temperature is derived, and a computational imaging method that combines optical design and image restoration is proposed. Finally, a dual-infrared waveband infrared optical system with athermalization and achromatic aberrations corrected based on computational imaging method is designed. Results show that this method can effectively reduce the diffraction efficiency of MLDOE by ambient temperature and improve the imaging quality of hybrid optical systems.

Machine Learning Assisted Ultra-Wideband Fiber-Optics Mode Selective Coupler Design

We report a machine learning assisted design strategy for ultra-wideband fiber-optics mode selective coupler (MSC). With the help of deep neural network (DNN), we are able to efficiently obtain the complex mapping relationship between structure parameters of the bridge fiber and effective refractive index (RI) of LP <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> mode over the S+C+L band. For high-order modes (HOMs) arising in the arbitrarily chosen few-mode fiber (FMF), the trained DNN can rapidly optimize the bridge fiber parameters. After optimization, the ultra-wideband phase matching between the effective RI of LP <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> mode arising in the bridge fiber and the effective RI of specific mode arising in the FMF over the S+C+L band can be realized. As an example, ultra-wideband fiber-optics 4-LP MSC with an average mode conversion efficiency (MCE) of more than 93% and an average mode extinction ratio (MER) of more than 17 dB can be secured. In comparison with the traditional genetic algorithm (GA), the DNN-assisted fiber-optics MSC design can significantly reduce the optimization time from 4 hours to 45 seconds, together with the maintenance of excellent ultra-wideband performance. Meanwhile, the ultra-wideband MSC for orbital angular momentum (OAM) mode conversion is demonstrated. Both OAM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+1</sub> and OAM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+2</sub> modes with an average mode purity of more than 97% and an average MCE of more than 89% over the S+C+L band can be secured. We envision the DNN-assisted fiber-optics device enables potential applications for future mode division multiplexing and wavelength division multiplexing hybrid optical transmission system.

Light fidelity performance via hybrid free space optic/fiber optic communication under atmospheric disturbance

Light f idelity (Li-Fi) considers technology in optical wireless communication (OWC) that utilize visible light for transmission in free space, visible light communication (VLC) technology was chosen to overcome the interference issues of radio frequency (RF) communication and it also has higher bandwidth and is more secure. This paper aims to analyse the influence of atmospheric attenuation on the end-users of VLC system that consisted of five light-emitting diodes (LEDs) distributed in a room, which in t urn linked with the hybrid optical system includes a multi-channel of free space optic (FSO) connected with a fiber-optic channel (FOC). The hybrid system to the end-user was estimated in terms of bit error rate, quality factor, and signal power under dust-rain weather conditions. In the dust scenario, the suggested system achieved acceptable bit-error-rate (BER) to a distance of 1, 100 m. In rainy conditions, the performance accomplished acceptable BER to a distance of 3000 m. The VLC system's end-user also was evaluated under the effectiveness of the variation of irradiance and incident angles. Despite the harsh environmental conditions imposed on the communication network, VLC has proven its ability to maintain acceptable performance in end-user.

Refractive-diffractive hybrid optics array: comparative analysis of simulation and experiments

Hybrid optical elements, which combine refractive and diffractive optical components to enhance optical performance by taking advantage of the optical characteristics of the individual components, have enormous potential for next-generation optical devices. However, there have not been many reports on the simulation methodology to characterize such hybrid optical systems. Here, we present a method for simulating a hybrid optical element realized by attaching an ultra-thin, flexible diffractive optics array onto a refractive optical element. The ultra-thin diffractive optical element is fabricated by direct-laser-writing using a femtosecond pulsed laser as the light source. A systematic investigation of the proposed simulation method, which does not require extensive hardware resources or computational time, but retains resolution and accuracy, is presented. The proposed scheme is validated by comparing simulation and experimental results. The simulation and experimental results on the spot size and focal length for the diffractive Fresnel zone plate (FZP) match well, with typical errors of less than 6%. The aspect ratio of the focal spot sizes at the compound and FZP focal planes of the hybrid optical system from the simulation and experiment also match quite well, with typical errors below 7%. This simulation scheme will expedite the designs for novel hybrid optical systems with optimal optical performances for specific applications, such as microfluidics and aberration-controlled optics.