Dynamic Light Control Research Articles

Web-based Internet of Things on environmental and lighting control and monitoring system using node-RED, MQTT and Modbus communications within embedded Linux platform

This paper presents our innovative approach in the field of Internet of Things (IoT). Our focus was on enhancing the research environment at Cheng Shiu University's laboratory through the creation of a dynamic network monitoring setup and lighting control system. Our aim was to simplify equipment management and promote energy efficiency. The core of our development is the Raspberry Pi 4B embedded Linux platform, which serves as a host for both a Message Queuing Telemetry Transport (MQTT) broker and a Node-RED server. Python programs, developed in PyCharm IDE, utilize multiple threads for efficient data exchange via Modbus TCP and MQTT protocols, facilitating seamless interaction between PLCs and MQTT broker servers. The Node-RED IoT development tool was instrumental in crafting a cross-platform Human-Machine Interface (HMI) web server with MQTT Publish/Subscribe capabilities, ensuring smooth communication with the MQTT broker server. By configuring the Apache HTTP server to direct to the Node-RED web directory, we can effectively monitor laboratory conditions and manage the lighting system. The experimental results validate the cost-effectiveness of our approach in transforming traditional control systems into a web-based supervisory control system, thereby enhancing the overall functionality of existing equipment. This project underscores our commitment to advancing IoT solutions in practical settings.

Dynamic Spatial-Selective Metasurface with Multiple-Beam Interference.

The emergence of the metasurface has provided a versatile platform for the manipulation of light at the nanoscale. Recent research in metasurfaces has explored a plethora of dynamic control and switching of multifunctionalities, paving the way for innovative applications in fields such as imaging, sensing, and communication. However, current dynamic multifunctional metasurfaces face challenges in terms of functional scalability and selective activation. In this work, we introduce and experimentally demonstrate a strategy that utilizes multiple plane waves to create arbitrary periodic patterns on the metasurface, thus enabling the dynamic and arbitrary spatial-selective activation of its embedded multiplexed functionalities. Furthermore, our strategy facilitates dynamic light control through mechanical translation, as demonstrated by a high-speed, dynamically switchable beam deflection scenario. Our method effectively overcomes the limitations associated with traditional spatially multiplexing techniques, offering greater flexibility and selectivity for dynamic control in multifunctional metasurfaces.

Tunable Mid‐Infrared Multi‐Resonant Graphene‐Metal Hybrid Metasurfaces

AbstractElectrically tunable graphene‐metal metasurfaces with controllable optical properties have attracted interest for straightforward manipulation of free space light. Their resonance tuning range depends on graphene's electrical transport characteristics, which are affected by its quality, operating conditions, and the device design. An important example of the latter is the direct contact of metallic antennas with the graphene layer that limits the extent to which a bias voltage can tune the metasurface's permittivity. In this work, this issue is resolved in a straightforward and fabrication‐efficient way for graphene‐metal hybrid metasurfaces with multiple plasmonic resonances. It is demonstrated that the incorporation of a 10 nm Al2O3 barrier layer enhances the tuning range of mid‐infrared resonances compared to metasurfaces without barrier layer, i.e., from 300 to 700 nm for a 7.3 µm resonance and from 110 to 140 nm for a 4.7 µm resonance. The improved tunability of the metal/dielectric/graphene metasurface can be attributed to the reduced electrical coupling between metal and graphene, as confirmed by an equivalent circuit model. These results bring closer the use of active metasurfaces based on two‐dimensional materials under ambient conditions, with possible applications as optical filters, modulators, and information processing devices that require dynamic control of light.

Cryogenic survival: Analysis and development of 'lost with frost' a 2D Python-based RPG game

This paper presents "Lost with Frost," a 2D Python-based RPG game developed by a team of three. The game immerses the player in a challenging survival experience within a frigid, snowy landscape, requiring strategic resource gathering and enemy encounters. The objective is to sustain the character's health by collecting sticks to fuel a central firepit. The paper details the game's core mechanics, including resource management, survival elements, and enemy interactions. It also highlights the iterative development process, addressing challenges faced and showcasing the team's creative and technical efforts. The game's design concept evolved from brainstorming sessions, emphasizing hardcore survival and exploration in a frozen land. The gameplay is dynamic, with the addition of day-night cycles affecting visibility and immersion. Unique features like dynamic lighting, UI enhancements, and sound control further enrich the gaming experience. The paper delves into the challenges encountered during development, such as refining map generation, object distribution, and gameplay balance. The team's journey through these challenges offers valuable insights into game creation, resulting in an engaging and visually appealing RPG adventure that transports players to a frosty, perilous world.

ЭНЕРГОЭФФЕКТИВНОЕ ОСВЕЩЕНИЕ ДЛЯ ВЫРАЩИВАНИЯ МИКРОЗЕЛЕНИ НА ВЕРТИКАЛЬНЫХ ФЕРМАХ

Vertical farms are a new approach to growing vegetables and berries, caused by the development of lighting technology and digitalization of technological processes. In Russia, the vertical farm market is just beginning to develop. The issue of high cost of manufactured products remains relevant. The cost of production is 1.3-1.5 times higher than the market average. This is due to the high costs of energy resources, primarily electricity. The main share of electricity is accounted for by lighting systems (80-90 percent). (Research purpose) The research purpose is creating the next generation of dynamic engineering systems, primarily lighting systems for vertical farms with intelligent control based on a differentiated day-to-day electricity tariff using digital technologies. (Materials and methods) Conducted production tests of dynamic lighting control methods at one of the sites of the ReTEK company, which made it possible to identify a more advanced and energy-efficient technology for controlling the vertical farm lighting system. The studies were carried out indoors without access to natural light, the air temperature during the production tests was 20-23 degrees Celsius with a relative humidity of 60-70 percent. (Results and discussion) It was found that the fresh weight of microgreening plants under experimental light was 18.5 percent higher than under control. It was determined that the cost of electricity consumed per 1 kilogram of micro-green under experimental light turned out to be 55.4 percent lower than under control. (Conclusions) It has been shown that the creation of the next generation of dynamic engineering systems, primarily lighting systems for vertical farms with intelligent control based on a differentiated day-to-day electricity tariff using digital technologies can significantly reduce energy costs and, as a result, reduce the cost of agricultural production.

Automated dynamic lighting control system to reduce energy consumption in daylight

Buildings, which are responsible for the majority of electricity consumption in cities like Dubai, are often exclusively reliant on electrical lighting even in the presence of daylight to meet the illumination requirements of the building. This inefficient use of lighting creates potential to further optimize the energy efficiency of buildings by complementing natural light with electrical lighting. Prior research has mostly used ballasts (variable resistors) to regulate the brightness of bulbs. There has been limited research pertaining to the use of pulse width modulation (PWM) and the use of ‘triodes for alternating current’ (TRIACs). PWM and TRIACs rapidly stop and restart the flow of current to the bulb thus saving energy whilst maintaining a constant illumination level of a space. We conducted experiments to investigate the feasibility of using TRIACs and PWM in regulating the brightness of bulbs. We also established the relationship between power and brightness within the experimental setups. Our results indicate that lighting systems can be regulated through these alternate methods and that there is potential to save up to 16% of energy used without affecting the overall lighting of a given space. Since most energy used in buildings is still produced through fossil fuels, energy savings from lighting systems could contribute towards a lower carbon footprint. Our study provides an innovative solution to conserve light energy in buildings during daytime.

Sensitivity analysis of sensor placement in energy-efficient, grid-interactive ready small office buildings with dynamic shading and lighting control

In smart buildings, dynamically controlled lighting and shading devices have a direct impact on occupants’ thermal and visual comfort, building energy use, and peak demand. This study aims to assess the impacts of adjusting vertical and work plane illuminance sensor location and rotation for different zone orientations across different climate zones, on illuminance levels, glare, energy consumption, and demand. Using the sensor locations of 1.6 m and facing the window (typical assumption), when implementing the integrated shading and lighting controls, the lighting and cooling energy savings range from 41% to 71% across both heating and cooling-dominated climate zones. The greatest cooling peak use demand reduction of 6.5 kW (23%) is achieved in Climate Zone 2 A, where the total cooling and lighting demand savings are 28-33% (9-10 kW). The percent change in lighting energy use is greater as compared to the percent change in cooling energy use when sensor location is varied, however, the total kWh and kW change is greater for cooling in most climate zones. Results suggest that adjusting the sensor distance from the window has a greater impact on illuminance levels, glare, and lighting and cooling energy use in all climate zones as compared to sensor rotation.

Optimized, highly efficient silicon antennas for optical phased arrays

Silicon photonics, in conjunction with complementary metal-oxide-semiconductor (CMOS) fabrication, has greatly enhanced the development of integrated optical phased arrays. This facilitates a dynamic control of light in a compact form factor that enables the synthesis of arbitrary complex wavefronts in the infrared spectrum. We numerically demonstrate a large-scale two-dimensional silicon-based optical phased array (OPA) composed of nanoantennas with circular gratings that are balanced in power and aligned in phase, required for producing elegant radiation patterns in the far-field. For a wavelength of 1.55 μm, we optimize two antennas for the OPA exhibiting an upward radiation efficiency as high as 90%, with almost 6.8% of optical power concentrated in the field of view. Additionally, we believe that the proposed OPAs can be easily fabricated and would have the ability to generate complex holographic images, rendering them an attractive candidate for a wide range of applications like LiDAR sensors, optical trapping, optogenetic stimulation, and augmented-reality displays.

Stimuli‐responsive active materials for dynamic control of light field

AbstractThe increasing demand for the multidimensional and dynamic control of light has spurred the development of stimuli‐responsive, reconfigurable, and programmable optical systems. Liquid crystals (LCs), which combine liquid‐like stimuli‐responsiveness and crystal‐like orientational ordering, have emerged as highly appealing soft materials. Owing to their exceptional optical performance and programmable functionalities, they are becoming incredibly important materials in active planar optics and photonics. Additionally, silk proteins, luminescent materials, and metasurfaces exhibit dynamic optical properties, enabling remarkable multifunctional applications. This review focuses on the advancements in stimuli‐responsive materials, including LCs, silk proteins, luminescent materials, and active metasurfaces as well as some of these materials paired with LCs. Their attractive tunable applications in optics and photonics, along with the great potential for the future development of active optical systems, are also emphasized.

Dynamic control of light scattering in a single particle enabled by time modulation

The interaction of light with time-varying materials offers intriguing opportunities for controlling light scattering and wavefront manipulation, thereby unlocking fascinating applications in the realm of optics and photonics. In this study, we present an analytical solution for the scattering from a particle made of a material with time-varying permittivity by exploiting the T-matrix approach. Through the manipulation of the active medium's eigenvalues, we demonstrate the pivotal ability to regulate the elements of a dynamically controlled T-matrix, thus enabling precise control over the scattering characteristics of the particle. Crucially, this dynamic control is achieved without resorting to modifying the particle's inherent physical parameters, such as shape, size, and dispersion. We demonstrate that the eigenvalues of the dynamic material can be skillfully manipulated through the adequate choice of the particle's modulation function, resulting in either in-phase or out-of-phase interactions between the magnetic and electric dipole modes, allowing us to satisfy the Kerker conditions at diverse harmonics. The results of the optimal modulation functions are presented in both the near-field and far-field regions, revealing time modulation as a dynamic means of achieving unidirectional scattering. Our findings pave the way for developing time-varying structures comprising dynamic meta-atoms, offering valuable insight into advanced light–matter interactions, and providing lucrative guidance for future research in the realm of dynamic photonic systems.

Polarization- and Angle-Insensitive Tunable Metasurface for Electro-Optic Modulation

Tunable metasurfaces provide enormous degrees-of-freedom for dynamic control of light–matter interactions at sub-wavelength scales. However, the realization of polarization- and angle-insensitive active nanophotonic devices with low energy-consumption and high modulation depth remains a challenge. This letter reports gap plasmon resonance based electro-tunable metasurface for optical intensity modulation. The proposed metasurface features a 2D array of Au-nanograting on top of indium-tin-oxide (ITO)–Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> –Au stack. The external electrical biasing accumulates the free-carriers of ITO at ITO–Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> interface, which results in an electro-tunable resonance response in the reflectance spectrum. With a 2V electrical biasing, we observe the resonance dip shifts to the vicinity of 1.55 μm wavelength. Thus, a modulation depth of ~25 dB at 1.55 μm can be achieved for random polarization-angle of incident light. For the first time, the proposed modulator can operate over a wide range of incidence angle (up to 50 degrees) for both x- and y-polarized light. With ~303 fJ/bit energy-consumption and ~900 Mbps modulation speed, the proposed electro-tunable metasurface could help to realize polarization- and angle-independent active flat optics for nanophotonic systems.

Functional soft materials from blue phase liquid crystals.

Blue phase (BP) liquid crystals are chiral fluids wherein millions of molecules self-assemble into cubic lattices that are on the order of hundred nanometers. As the unit cell sizes of BPs are comparable to the wavelength of light, they exhibit selective Bragg reflections in the visible. The exploitation of the photonic properties of BPs for technological applications is made possible through photopolymerization, a process that renders mechanical robustness and thermal stability. We review here the preparation and characterization of stimuli-responsive, polymeric photonic crystals based on BPs. We highlight recent studies that demonstrate the promise that polymerized BP photonic crystals hold for colorimetric sensing and dynamic light control. We review using Landau-de Gennes simulations for predicting the self-assembly of BPs and the potential for using theory to guide experimental design. Finally, opportunities for using BPs to synthesize new soft materials, such as highly structured polymer meshes, are discussed.

Electro-optic modulation using lithium niobate metasurfaces with topological corner state

Electro-optically (EO) tunable metasurfaces have received considerable attention owing to their capability for dynamic light field control. Here, we report an EO lithium niobate metasurface mediated by topological corner states. Such a supercell of metasurface is constructed by two kinds of finite-sized arrays possessing different topological properties via the generalized two-dimensional (2D) Su–Schrieffer–Heeger model. The generated narrow-linewidth resonance with high-quality factor and strong field localization are very suitable for EO modulation. The results reveal that the required driving external voltage to fully shift the resonance can be well below 15 V. Furthermore, the 0.46 rad of phase modulation is also demonstrated along with transmission intensity modulation. The results offer a fundamental path of potential for tunable displays, light detection, spatial light modulators, and Floquet topological metasurfaces.

Design and implementation of a real-time demonstration setup for dynamic highway tunnel lighting control research studies

This study presents the design and implementation of a computer-based real-time demonstration setup for dynamic highway tunnel lighting control research studies. The energy-efficient and controllable lighting systems stand out worldwide because of energy efficiency objectives and carbon footprint reduction goals of the countries. An LED (Light Emitting Diode) armature-based highway lighting systems are frequently utilized in recent years due to lighting efficiency, energy efficiency, long life, environmentally and cost-friendly structure of the LEDs as well as zero ultraviolet emissions of them. In this study, the LED-based dynamic tunnel lighting control approach has been implemented through the proposed demonstration setup which is a typical real-time software-controlled hardware. The parts of the proposed demonstration setup have been introduced and detailed to help with some upgrade studies in the future. The demonstration setup has been tested in some case studies, then the obtained results have been discussed and introduced. In the future, the proposed system can be upgraded and utilized for advanced control studies thanks to its computer-based and simulation environment connection capability.

Programmable and adaptable navigation of a magnetic and photoactive colloid

Colloids that are able to navigate via predefined paths and adapt to complex environments hold great promises as miniaturized machines and model systems for active soft matter research. Here, we design an intelligent system that integrates dynamic magnetic field and light control with in-situ determination of particle position and velocity via Matlab-based image acquisition and analysis. We apply the system to realize programmable and feedback control over the motion of a magnetic and photoactive colloid. Specifically, we direct the active colloid into pentagram-like navigation, circular motion of various size, and spiral-like motion by changing the travelling direction, discretely or continuously, the self-propelled velocity, and a combination of the two, enabled by dynamic change of magnetic field, light intensity and both. Moreover, we demonstrate the ability of the system for on-the-fly self-correction to follow predefined path with high fidelity, and adaptability to complex surroundings with definable birdlike vision based on in-situ processing of information. We expect the programmability and adaptability of magnetic and photoactive colloids enabled by multiple handles, magnetic field and light, open up new opportunities for active soft matter research, including intelligent microrobotics, collective nonequilibrium dynamics and novel photonic fluids.

Metasurfaces for Sensing Applications: Gas, Bio and Chemical

Performance of photonic devices critically depends upon their efficiency on controlling the flow of light therein. In the recent past, the implementation of plasmonics, two-dimensional (2D) materials and metamaterials for enhanced light-matter interaction (through concepts such as sub-wavelength light confinement and dynamic wavefront shape manipulation) led to diverse applications belonging to spectroscopy, imaging and optical sensing etc. While 2D materials such as graphene, MoS2 etc., are still being explored in optical sensing in last few years, the application of plasmonics and metamaterials is limited owing to the involvement of noble metals having a constant electron density. The capability of competently controlling the electron density of noble metals is very limited. Further, due to absorption characteristics of metals, the plasmonic and metamaterial devices suffer from large optical loss. Hence, the photonic devices (sensors, in particular) require that an efficient dynamic control of light at nanoscale through field (electric or optical) variation using substitute low-loss materials. One such option may be plasmonic metasurfaces. Metasurfaces are arrays of optical antenna-like anisotropic structures (sub-wavelength size), which are designated to control the amplitude and phase of reflected, scattered and transmitted components of incident light radiation. The present review put forth recent development on metamaterial and metastructure-based various sensors.

On the Study of Advanced Nanostructured Semiconductor-Based Metamaterial

Tunable metamaterials belonging to the class of different reconfigurable optical devices have proved to be an excellent candidate for dynamic and efficient light control. However, due to the consistent optical response of metals, there are some limitations aiming to directly engineer electromagnetic resonances of widespread metal-based composites. The former is accomplished by altering the features or structures of substrates around the resonant unit cells only. In this regard, the adjusting of metallic composites has considerably weak performance. Herein, we make a step forward by providing deep insight into a direct tuning approach for semiconductor-based composites. The resonance behavior of their properties can be dramatically affected by manipulating the distribution of free carriers in unit cells under an applied voltage. The mentioned approach has been demonstrated in the case of semiconductor metamaterials by comparing the enhanced propagation of surface plasmon polaritons with a conventional semiconductor/air case. Theoretically, the presented approach provides a fertile ground to simplify the configuration of engineerable composites and provides a fertile ground for applications in ultrathin, linearly tunable, and on-chip integrated optical components. These include reconfigurable ultrathin lenses, nanoscale spatial light modulators, and optical cavities with switchable resonance modes.

Development of New Radar and Pyroelectric Sensors for Road Safety Increase in Cloud-Based Multi-Agent Control Application

The paper concentrates on the design, architecture, and monitoring of smart LED street lighting control, with focus on traffic safety and safe road infrastructure. The use of a CMAS (Cloud-Based Multi-Agent System) as a possible framework is investigated. The work is based on previous developments by the authors in the production and design of close and long-range hybrid Pyroelectric Infrared (PIR) motion detection sensors. It also introduces the advances in radar-type sensors used in smart SLC (street lighting control) application systems. The proposed sensor solutions can detect the road user (vehicle or pedestrian) and determine its movement direction and approximate speed that can be used for dynamic lighting control algorithms, traffic intensity prediction, and increased safety for both driver and pedestrian traffic. Furthermore, the street lighting system infrastructure can monitor city environmental parameters, such as temperature, humidity, CO2 levels, thus increasing levels of safety and security for smart cities. Utilising other hybrid systems within intelligent street lighting applications represents a new specialisation area in both energy-saving, safety awareness, and intelligent management.

Sustainable polymer materials for flexible light control and thermal management

AbstractThe urgency of the global energy and climate crises demands quick development of energy‐saving and temperature regulating technologies. Efficient thermal management by selective control of visible and infrared light is possible with advanced optical materials. Already, garments are being functionalized with such materials and may significantly reduce indoor heating and cooling costs, for which a huge (~10% in the United States) amount of energy is consumed. The ability to harness light also enables other technologies including dynamic camouflage and photoactivated self‐decontaminating surfaces. Although much focus has been placed on carbon and inorganic nanomaterials for these applications, this perspective investigates optically active polymer materials as arguably more benign alternatives for flexible devices. Passive and dynamic control of light for heating and cooling using polymers is covered, as well as a discussion comparing conjugated polymers with commonly used nanomaterials.

Multistate Tuning of Third Harmonic Generation in Fano‐Resonant Hybrid Dielectric Metasurfaces

AbstractHybrid dielectric metasurfaces have emerged as a promising approach to enhancing near field confinement and thus high optical nonlinearity by utilizing low loss dielectric rather than relatively high loss metallic resonators. A wider range of applications can be realized if more design dimensions can be provided from material and fabrication perspectives to allow dynamic control of light. Here, tunable third harmonic generation (THG) via hybrid metasurfaces with phase change material Ge2Sb2Te5 (GST) deposited on top of amorphous silicon metasurfaces is demonstrated. Fano resonance is excited to confine the incident light inside the hybrid metasurfaces, and an experimental quality factor (Q‐factor ≈ 125) is achieved at the fundamental pump wavelength around 1210 nm. Not only the switching between a turn‐on state of Fano resonance in the amorphous state of GST and a turn‐off state in its crystalline state are demonstrated, but also gradual multistate tuning of THG emission at its intermediate states. A high THG conversion efficiency of η = 2.9 × 10−6% is achieved, which is 32 times more than that of a GST‐based Fabry–Pèrot cavity under a similar pump laser power. Experimental results show the potential of exploring GST‐based hybrid dielectric metasurfaces for tunable nonlinear optical devices.