LED Matrix Research Articles

Motion-free high-resolution on-chip microscopy using LED matrix

Lensless microscopy is an imaging technique that allows high-resolution imaging over a large field of view with a cost-effective design. Conventional lensless microscopy often utilizes multi-height phase retrieval and pixel-super-resolution algorithms to reconstruct high-resolution images, requiring mechanical stages for three-dimensional relative movements between a light source, camera, and sample. However, the excessive use of stages inevitably increases the bulkiness of the system and extends the image acquisition time. Here, we propose a motion-free lensless microscope that incorporates an RGB LED matrix array. A high-resolution holographic image is reconstructed from subpixel-shifted color images obtained with LED illuminations without any mechanical movement. Using a prototype system, we have demonstrated a spatial-bandwidth product of 30 megapixels with a resolution of 0.87 µm and a field of view of 24 mm2. The usability of the proposed method has been further tested for histopathologic examination. Our system features a compact and high-performance design with inexpensive optoelectronic elements, a conventional CMOS sensor and an LED matrix, which are well-aligned with the original design motivation of lensless imaging methods.

LANTERN: A multichannel light calibration system for cryogenic detectors

Recent advancements in low-energy rare-event searches rely on the use of cryogenic calorimeters in order to reach extremely low energy thresholds. When attempting to accurately characterize their responses within the region of interest (ROI) these detectors face severe challenges due to the fact that traditional radioactive calibration sources produce signals above the ROI and cannot be used in low background environments.LANTERN, an optical calibration system, can instead be used to accurately study the ROI of cryogenic detectors. It utilizes LED pulses to generate photon signals to perform detector calibration. LANTERN’s current LED matrix allows for a fast characterization of up to 64 calorimeters independently, spanning energies from a few eV to hundreds of keV. Its minimal electronics and optics make it a cost-effective and customizable solution and it will be employed by the BULLKID, NUCLEUS and CRAB experiments.

OVERVIEW OF THE INFLUENCE OF INNOVATIVE TECHNOLOGIES ON EXPANDING THE FUNCTIONAL CAPABILITIES OF AUTOMOBILE HEADLIGHTS, ON THEIR PHOTOMETRIC CHARACTERISTICS AND METHODS AND MEANS OF THEIR CONTROL UNDER THE CONDITIONS OF OPERATION

A brief overview of the features and possibilities of innovative technologies in the field of front light-ing systems of mechanical vehicles, in particular, adaptive front lighting systems, intelligent front lighting sys-tems and modern digital lighting systems, was conducted. The main features of the structure and operation of such systems are considered, and some characteristics and capabilities of the front lighting systems used in Mercedes-Benz cars are given. Analyzed the requirements of the UNECE Rules and state standards of Ukraine in force in Ukraine with the requirements for methods and means of monitoring the conformity of installation parameters and photometric characteristics of front lighting systems during the operation of cars and the re-quirements of the manufacturer’s normative and technological documents for the performance of control, di-agnostic and regulatory maintenance work front lighting systems of Mercedes-Benz cars. The results of the work performed were used in the development of methodological instructions for the performance by NTU stu-dents of laboratory work on maintenance and inspection of the condition and adjustments of Mercedes-Benz headlights. Based on the results of the research, proposals and recommendations have been developed regard-ing the expediency of making changes to the state standards and regulatory documents in force in Ukraine, which regulate the performance of works to control the compliance of the technical condition of mechanical road vehicles with safety requirements in terms of external lighting devices. Also, recommendations have been developed for the use of control and diagnostic equipment, with which it is advisable to equip posts for mainte-nance of external light devices of Mercedes-Benz cars by maintenance stations located in Ukraine. Keywords: car headlight, adaptive front lighting system, intelligent front lighting system, digital lighting sys-tem, dynamic cornering lighting, static cornering lighting, low beam headlights, high beam headlights, adaptive low beam, adaptive high beam, city light mode, extra-urban mode light, light mode on highways; advanced fog light mode, fog light, matrix LED light, light with micro-opto-electromechanical system.

Sync Alert Notice Board

The SyncAlert Notice Board project represents a significant advancement in communication technology, leveraging a sophisticated integration of hardware components to create a versatile communication hub. At its core, the project features a 45x6 LED matrix, enabling vivid and customizable display capabilities for messages and notifications. This matrix is complemented by an RTC (Real-Time Clock) module, ensuring accurate timekeeping and scheduling functionalities essential for managing events and deadlines effectively. In addition to visual communication, the project incorporates an MP3 module, adding an auditory dimension to message delivery and enhancing user engagement. The integration of a Bluetooth HC05 module further enhances the project's utility by enabling seamless wireless transmission of data, allowing users to update the notice board remotely and in real time. This combination of features transforms the SyncAlert Notice Board into a dynamic and interactive communication tool suitable for a wide range of environments, from educational institutions to corporate offices. By addressing the specific needs of users for efficient information dissemination and scheduling management, the SyncAlert Notice Board project offers a comprehensive solution that not only streamlines communication but also enhances organizational productivity and engagement. Its versatility, coupled with user-friendly functionality, makes it an invaluable asset for any setting where clear and timely communication is paramount

Simulation Of A Trash Can Using Line Follower Based On Arduino

There is a lot of dirt scattered around the State Elementary School (SDN) 03 Purwoyoso, Semarang. The habit of elementary school children and their parents is that they often throw rubbish everywhere and are lazy about throwing away the rubbish. even though there are already rubbish bins provided at the school. Children like new things, especially those shaped like toys. Garbage is a nesting place for bacteria that can cause various diseases. Humans are blessed with five senses which help them detect various things that threaten their lives. However, in the modern world, various forms of threats emerge that are not detected by our five senses, namely various types of poisons made by humans themselves. More than 75,000 synthetic chemicals have been produced by humans in the last decades. Many of them have no color, taste and smell, but have the potential to cause health hazards. Based on the problems described, the author tries to make a trash can using an Arduino-based line follower as a micro controller. This trash can can walk to the desired student line in a certain area with control carried out by a calling mechanism using a recorded voice. And if the smell is strong, the Buzzer will sound, after the students throw away the trash , the Dot Matrix LED will light up the words Thank You. It is hoped that with this rubbish bin, it will make the rubbish bin more attractive so that children will throw rubbish in its place.

SIMULARE NUMERICĂ A INFLUENȚEI UNOR PARAMETRI GEOMETRICI ASUPRA CALITATII DECONTAMINARII UNUI RECEPTOR DE TIP NON-LAMBERTIAN, UTILIZAND O MATRICE DE LED-uri UV-C

The ultraviolet (UV) irradiation has been studied and used in the recent decades as a mean to inactivate various potentially harmful microorganisms, being considered an effective treatment that could limit or even avoid the use of chemical disinfectants. Within the wavelength spectrum of UV radiation, the UV-C radiation wavelength ranging between 200 and 280 nm is considered lethal to most types of microorganisms. In this paper it was studied the variation of the distribution of radiation's intensity generated by a matrix of 25 UV-C LEDs (5 x 5), (assimilated to the LED panel above a stationary conveyor), on a spherical surface (assimilated to a berry) positioned in reprezentative locations below the matrix. A fruit located under the irradiation matrix receives the strongest radiation from the LED located at the smallest distance from it, but is influenced, as a result of the superposition principle, to a lesser extent by the other LEDs within the network. It has been found that for a too small distance between the matrix of LEDs and the conveyor, the radiation dose is uneven on the surface of fruit, and by increasing this distance a radiation distribution much more uniform is obtained, but at the expense of a decrease in its intensity and an increase in the time required for irradiation, implicitly leading to an increase in operating costs. In conclusion, for the most efficient operation of the equipment, a compromise solution must be chosen.

Effect of Ce<sup>3+</sup> Concentration and YAG Crystal Particles Size on Photoluminescence

Purpose of research. Determine the effect on the photoluminescence of phosphors from yttrium-aluminum garnet activated by cerium ions Ce3+, the size of its particles and the concentration of cerium ions in them.Methods. Structural electron and confocal microscopic, fluorescent, microspectral studies using a laser lex = 473 nm as an excitation source, energy dispersive, X-ray diffraction studies, as well as goniophotometric measurements on the radial distribution of light intensity excited by the LED matrix were carried out.Results. A detailed granulometric analysis of the particle sizes of phosphors was carried out for two samples from different manufacturers, cumulative distributions M(d) were constructed and their quantiles were established. Based on the results of measuring photoluminescence from individual particles in the compositions of phosphors based on YAG:Ce3+, a Stokes shift was detected in these samples: short-wavelength – for particles with sizes less than 10 μm and with low concentration and long-wavelength – with sizes greater than 10 μm with an increased concentration of over ~0.2% . The obtained microspectral size-emission dependences lem(d) and energy Imax(d) were consistent with the description based on the proposed physical mechanism of their formation by the 5d → 2F5/2 and 5d → 2F7/2 transitions.Conclusion. A short-wavelength shift of photoluminescence intensity maxima for particles smaller than 10 μm was discovered, due to a significant increase in the influence of surface stresses due to a reduction in the number of atoms. For larger particle sizes, the characteristic photoluminescence intensity maxima cease to depend on the wavelength. The radial distribution of luminous intensity determined by the goniophotometric method made it possible to calculate the value of the luminous flux equal to 1350 lm and 1140 lm, respectively, for LED matrices containing 8 LEDs with the studied phosphors.

Real-Time Patient Indoor Health Monitoring and Location Tracking with Optical Camera Communications on the Internet of Medical Things

Optical Camera Communication (OCC) is an emerging technology that has attracted research interest in recent decades. Unlike previous communication technologies, OCC uses visible light as the medium to transmit data from receivers and cameras to receive the data. OCC has several advantages that can be capitalized in several implementations. However, the Internet of Things (IoT) has emerged as a technology with immense potential. Numerous research endeavors support the IoT’s prospective technology that can be implemented in various sectors, including the healthcare system. This study introduces a novel implementation of the Internet of Medical Things (IoMT) system, using OCC for real-time health monitoring and indoor location tracking. The innovative system uses standard closed-circuit television CCTV setups, integrating deep learning-based OCC to monitor multiple patients simultaneously, each represented by an LED matrix. The effectiveness of the system was demonstrated through two scenarios: the first involves dual transmitters and a single camera, highlighting real-time monitoring of vital health data; the second features a transmitter with dual cameras, focusing patient movement tracking across different camera fields of view. To accurately locate and track the position of LED arrays in the camera, the system used YOLO (You Only Look Once). Data are securely transmitted to an edge server and stored using the REST API, with a web interface providing real-time patient updates. This study highlights the potential of OCC in IoMT for advanced patient care and proposes future exploration in larger healthcare systems and other IoT domains.

Precise Individual Illumination Control of Matrix LED With Bypass Gate Driver and 8-Bit PWM

Precise Individual Illumination Control of Matrix LED With Bypass Gate Driver and 8-Bit PWM

Controlling the target pattern of projected LED arrays for smart lighting.

High-resolution, pixelated LED arrays allow flexible illumination. By addressing certain areas of the LED matrix and projecting the emitted light, selective illumination can be achieved. When combined with computer vision, smart, autonomous lighting systems are within reach. However, limitations of the used projection optics, in combination with the fact that the LED array and camera can be at a different position, severely complicates the problem of calculating which LED pixels to address in order to achieve a desired target pattern. This work proposes a least-squares deconvolution-based calculation method to solve this problem. The method relies on an initial calibration step that characterizes the complete point-spread-function of the LED array for the considered illumination configuration. This allows using the system for various settings. The method is experimentally validated for an off-axis illumination configuration that demonstrates the accuracy and flexibility of the approach. Because the proposed algorithm is fast and guarantees a global optimum, it opens new avenues towards accurate, smart and adaptive illumination.

Photothermal Lithography for Realizing a Stretchable Multilayer Electronic Circuit Using a Laser.

Photolithography is a well-established fabrication method for realizing multilayer electronic circuits. However, it is challenging to adopt photolithography to fabricate intrinsically stretchable multilayer electronic circuits fully composed of an elastomeric matrix, due to the opacity of thick stretchable nanocomposite conductors. Here, we present photothermal lithography that can pattern elastomeric conductors and via holes using pulsed lasers. The photothermal-patterned stretchable nanocomposite conductor exhibits 3 times higher conductivity (5940 S cm-1) and 5 orders of magnitude lower resistance change (R/R0 = 40) under a 30% strained 5000th cyclic stretch, compared to those of a screen-printed conductor, based on the percolation network formed by spatial heating of the laser. In addition, a 50 μm sized stretchable via holes can be patterned on the passivation without material ablation and electrical degradation of the bottom conductor. By repeatedly patterning the conductor and via holes, highly conductive and durable multilayer circuits can be stacked with layer-by-layer material integration. Finally, a stretchable wireless pressure sensor and passive matrix LED array are demonstrated, thus showing the potential for a stretchable multilayer electronic circuit with durability, high density, and multifunctionality.

Fine Flow Structure at the Miscible Fluids Contact Domain Boundary in the Impact Mode of Free-Falling Drop Coalescence

Registration of the flow pattern and the matter distribution of a free falling liquid drop in a target fluid at rest in the impact mode of coalescence when the kinetic energy (KEn) of the drop exceeds its available surface potential energy (ASPe) was carried out by photo and video recording. We studied the evolution of the fine flow structure at the initial stage of the cavity formation. To carry out color registration, the observation field was illuminated by several matrix LED and fiber-optic sources of constant light. The planning of experiments and interpretation of the results were based on the properties of the complete solutions of the fundamental equations of a fluid mechanics system, including the transfer and conversion of energy processes. Complete solutions of the system of equations describe large-scale flow components that are waves or vortices as well as thin jets (ligaments, filaments, fibers, trickles). In experiments, the jets are accelerated by the converted available surface potential energy (ASPe) when the free surfaces of merging fluids were eliminated. The experiments were performed with the coalescence of water, solutions of alizarin ink, potassium permanganate, and copper sulfate or iron sulfate drops in deep water. In all cases, at the initial contact, the drop begins to lose its continuity and breaks up into a thin veil and jets, the velocity of which exceeds the drop contact velocity. Small droplets, the size of which grows with time, are thrown into the air from spikes at the jet tops. On the surface of the liquid, the fine jets leave colored traces that form linear and reticular structures. Part of the jets penetrating through the bottom and wall of the cavity forms an intermediate covering layer. The jets forming the inside layer are separated by interfaces of the target fluid. The processes of molecular diffusion equalize the density differences and form an intermediate layer with sharp boundaries in the target fluid. All noted structural features of the flow are also visualized when a fresh water drop isothermally spreads in the same tap water. Molecular diffusion processes gradually smooth out the fast-changing boundary of merging fluids, which at the initial stage has a complex and irregular shape. Similar flow patterns were observed in all performed experiments; however, the geometric features of the flow depend on the individual thermodynamic and kinetic parameters of the contacting fluids.

The Use of Fresnel Lenses in LED Sources of Local Illumination to Оptimize the Distribution of Illumination of the Working Plane

For widely used LED sources there is a sharp decrease in the illumination of the working plane from the center to the edge. The purpose of this study was to analyze the effectiveness of Fresnel lenses usage as a fairly simple and technological element to increase the uniformity of illumination created by LED lamps of local lighting.A method has been developed for calculating of the distribution of illumination created by the combination of “LED matrix – Fresnel lens” when the distance between the lens and the matrix is less than the focal length of the lens. Comparison of the calculation results and experiments for the case when the lens is located at a distance of 50 cm from the working plane indicates the correctness of the developed calculation method. This made it possible to use this technique to solve the problem of improved uniformity of illumination distribution in the working plane of local lighting LED sources.It was found that the change in the distance between the matrix and the lens in the range of 0.5–1.5 cm affects the maximum illumination and its uniformity to a lesser extent than the change in focal lengths in the range of 10–100 cm. Analytical dependences of the uniformity of the working surface illumination as a function of the Fresnel lens focal length and its distance to the LED matrix were obtained for three cases. In the first case one lens is used for the entire matrix while the axes of symmetry of the light intensity curves of LEDs are parallel to the axis of the lens. In the second case one lens is also used for the entire matrix, but the continuations of the axes of symmetry of the light intensity curves pass through the front focus of the lens. In the third one an individual Fresnel lens is used for each LED. It is established that for all three cases dependencies have almost the same character. Therefore, the choice of using one of these three options may be due to manufacturability, cost-effectiveness, thermal stability, and other considerations.Calculations using the above-mentioned analytical dependences made it possible to determine values of the parameters of the “LED matrix – Fresnel lens” system at which the indicators of illumination and uniformity meet the standards’ requirements.

A Controller System for LED Matrix Headlights with Adjustable Brightness and Color

A Controller System for LED Matrix Headlights with Adjustable Brightness and Color

Method and Installation for Efficient Automatic Defect Inspection of Manufactured Paper Bowls

Various techniques were combined to optimize an optical inspection system designed to automatically inspect defects in manufactured paper bowls. A self-assembled system was utilized to capture images of defects on the bowls. The system employed an image sensor with a multi-pixel array that combined a complementary metal-oxide semiconductor and a photo detector. A combined ring light served as the light source, while an infrared (IR) LED matrix panel was used to provide constant IR light to highlight the outer edges of the objects being inspected. The techniques employed in this study to enhance defect inspections on produced paper bowls included Gaussian filtering, Sobel operators, binarization, and connected components. Captured images were processed using these technologies. Once the non-contact inspection system’s machine vision method was completed, defects on the produced paper bowls were inspected using the system developed in this study. Three inspection methods were used in this study: internal inspection, external inspection, and bottom inspection. All three methods were able to inspect surface features of produced paper bowls, including dirt, burrs, holes, and uneven thickness. The results of our study showed that the average time required for machine vision inspections of each paper bowl was significantly less than the time required for manual inspection. Therefore, the investigated machine vision system is an efficient method for inspecting defects in fabricated paper bowls.

Monitoring Power Consumption On LED Using LED Matrix P10 Panel

Information media is an essential medium in communication. So that the information provided is easy to see and read, the media used is placed in a visible place. Nowadays, data has become an inseparable part of process performance. With the advancement of technology, many new information media use electronic media that is used not only as news and advertising media but also as information media located in buildings or offices. Display running text matrix can be used to make the text according to the desired character. Besides, all Work and human needs are highly dependent on electrical energy. Human negligence in using electrical energy will cause waste, which also impacts the cost of using electrical energy. Therefore, we need a tool that can monitor the consumption of electrical power and limit the current use of the load, even if the user of electrical energy is not in place. Of course, making this tool requires a voltage sensor, sensor current ACS712, Arduino nano, and NodeMCU. This tool will monitor the power IoT-based and can be monitored via the internet as a graphical display on the server thingspeak.com. The results of this design can measure voltage one and voltage sensor two with an average error value of 1.75% and 1.38%, and the current measurement has an error value between 0.22% to 3.82% with an average error value of 1.46%.

Research and Evaluation on an Optical Automatic Detection System for the Defects of the Manufactured Paper Cups.

In this paper, the paper cups were used as the research objects, and the machine vision detection technology was combined with different image processing techniques to investigate a non-contact optical automatic detection system to identify the defects of the manufactured paper cups. The combined ring light was used as the light source, an infrared (IR) LED matrix panel was used to provide the IR light to constantly highlight the outer edges of the detected objects, and a multi-grid pixel array was used as the image sensor. The image processing techniques, including the Gaussian filter, Sobel operator, Binarization process, and connected component, were used to enhance the inspection and recognition of the defects existing in the produced paper cups. There were three different detection processes for paper cups, which were divided into internal, external, and bottom image acquisition processes. The present study demonstrated that all the detection processes could clearly detect the surface defect features of the manufactured paper cups, such as dirt, burrs, holes, and uneven thickness. Our study also revealed that the average time for the investigated Automatic Optical Detection to detect the defects on the paper cups was only 0.3 s.

Calculation of termostabilization system led matrices by heat pipes

Using the method of electrothermal analogy, a mathematical model of the thermal stabilization system of the LED matrix with a heat pipe was developed. The system of differential equations is solved, including the stationary equation of heat conduction and the equation of heat generation, which are supplemented by boundary conditions of conjugation for heat fluxes and temperatures. The calculated temperature distribution in the structural elements of the thermal stabilization system depending on the power of the LED matrix, heat pipe parameters and the temperature of the environment. It is shown that the use of the proposed thermal stabilization system will allow to increase the luminous flux of the LED-matrix (increase the light power) without increasing the temperature of its active zone. This will allow to reduce the number of LED-matrix in the semiconductor lamp and its cost without shortening the service life.

Design and Construction of a Double-Sided-Double-Line LED Matrix Display

Design and Construction of a Double-Sided-Double-Line LED Matrix Display

Quantum-Chromodynamics-Inspired 2D Multicolor LED Matrix to Camera Communication for User-Centric MIMO

With the high availability of low-cost and energy-efficient LEDs and cameras, there is increased interest in optical camera communication (OCC) to provide nonradio-frequency-based communication solutions in the domains of advertisement, vehicular communication, and the Internet of Things (IoT). As per the IEEE 802.15.7-2018 standard, new physical-layer clauses support low-frame-rate camera communication with allowable flickering. This paper proposes an OCC system that can provide user-centric multiple-input multiple-output (MIMO) loosely based on quantum-chromodynamics (QCD) concepts. A QCD–OCC simulator and prototype are proposed, implemented, and evaluated on the basis of the pixel intensity profile, peak signal-to-noise ratio (PSNR), the success of reception (%), bit-error rate (BER), and throughput under different ambient lighting conditions and distances. We observed 100% and 84% success of reception using the proposed prototype and simulator, respectively, for the data rate of 720 bps. The maximal tolerable BER of 1.13×10−2 for IoT applications was observed at a maximal distance of 200 cm and a maximal data rate of 3600 bps. The proposed system was also compared with other existing OCC systems with similar hardware and implementation requirements. The proposed QCD–OCC system provided rotation support up to 90 degrees and throughput of 4.32 kbps for a 30 fps camera.