Browse Topic: Lasers
Impacts of laser shock peening (LSP) on the evolution characteristics of microstructure in commercially pure α-phase titanium (α-Ti) are explored by molecular dynamics (MD) simulations of high strain-rate compression. The EAM potential (Zhou potential) is selected for its ability to capture the evolution of microstructures. Considering the LSP-induced peak plasma pressure, the strain rate during the simulated shock compression process is set at 10^9 s-1 to replicate the LSP process. The stress-strain curve of the α-Ti under high strain-rate compression is obtained. The maximum equivalent stress reaches 3.6 GPa, consistent with the theoretically calculated value. The simulation results reveal that mechanical twins (MTs) are activated at a strain of 3%. The number of mechanical twins increases and eventually stabilizes, forming a network structure throughout the grains. In the meantime, numerous partial dislocations are generated adjacent to the grain boundaries. The dislocation density also increases with strain and dislocation reactions occur. Moreover, grain refinement is identified. The grain size is refined from the initial ~ 8 nm to ~ 4 nm in the polycrystalline α-Ti. Twinning, together with dislocation-mediated plasticity, drives the refinement of grain size. Gradients of twin density, dislocation density, and grain size density are induced by LSP on the surface of α-Ti. This study comprehensively investigates how LSP influences the evolution of microstructures by MD simulations. It develops an innovative numerical strategy that offers a foundation for elucidating the underlying mechanisms of LSP.
In the rapidly evolving arena of high-power laser technology, precision and reliability are becoming increasingly important. The increasing powers in laser applications into the 10's of kW and, in some cases, 100's of kW, present additional challenges when applied to internal laser system components. For Precitec, respected globally for their advanced laser processing heads, delivering consistent performance to customers is both a challenge and a necessity. This case study explores how Precitec's U.S. operation has integrated laser measurement technology into its workflow; a non-contact beam characterization system significantly elevates the company's service, quality assurance, and development processes for high-power laser applications.
Gyroscopic effects split circumferential traveling-wave resonances of rotating structures into forward and backward branches. This work first analyzes the splitting in the co-rotating (Lagrangian) frame to provide physical intuition for the evolution of the two branches with spin speed. A transformation to the inertial (Eulerian) frame is then derived, showing that the observed frequencies are shifted by a kinematic Doppler-like term that acts with opposite sign on the forward and backward waves, leading to different Campbell-diagram slopes depending on the observation frame. The resulting framework is validated experimentally on a freely rotating, unloaded tire using two complementary sensing modalities: wireless on-tire accelerometers (co-rotating view) and a scanning laser Doppler vibrometer (inertial view). A frequency-domain SVD-based identification (FDD/ODS-SVD) is used to extract poles and deformation patterns over a range of spin speeds, enabling Campbell diagrams in both frames. The application of the proposed transformation maps the co-rotating branches onto the inertial observations, yielding consistent forward/backward splitting between the two measurement systems.
Astrolight recently demonstrated undetectable, unjammable, and high-bandwidth laser-based ship-to-ship communication with its POLARIS terminal during REPMUS’25, NATO’s largest unmanned maritime exercise.
Multimodal sensors, capable of simultaneously acquiring multiple physical or chemical signals, have shown broad application potential in fields such as health monitoring, soft robotics, and energy systems. However, current multimodal sensors often suffer from complex fabrication processes and signal decoupling challenges, which limit their practical deployment. To address these issues, this work presents a thin-film temperature–strain multimodal sensor (FTSMS) fabricated via laser processing. The temperature-sensing unit, based on the Seebeck effect, achieves a sensitivity of 9.08 μV/°C, while the strain-sensing unit, utilizing BaTiO₃/AlN@PDMS as the sensitive layer, exhibits a gauge factor (GF) of 43.2. By integrating distinct sensing mechanisms (thermovoltage for temperature and capacitance change for strain), the FTSMS enables self-decoupled measurements over 20–90 °C. Applied in LIB monitoring, it successfully captures real-time temperature and strain variations during charge-discharge cycles and provides multidimensional information throughout thermal runaway (TR) processes, enabling early TR warning and supporting safety-oriented battery design.
The objective of this study was to examine the effect of Correlated Colour Temperature (CCT) of automotive LED headlamps on driver’s visibility and comfort during night driving. The experiment was conducted on different headlamps having different correlated colour temperatures ranging from 5000K to 6500K in laboratory. Further study was conducted involving participants of different age group and genders for understanding their perception to identify objects when observed in light of different LED headlamps with different CCTs. Studies have shown that both Correlated Colour Temperature and illumination level affect driver’s alertness and performance. Further study required on headlamps with automatically varying CCT to get better solution on driver’s visibility and safety.
The light and light signaling devices installation test as per as per IS/ ISO 12509:2004 & IS/ISO 12509:2023 for Earth Moving Machinery / Construction Equipment Vehicles is a mandatory test to ensure the safety and comfort of both road users and operators. Considering the shape and size of construction equipment vehicles, accurate measurement of lighting installation requirements is crucial for ensuring safety and regulatory compliance. The international standard IS/ISO 12509:2004 & IS/ISO 12509:2023 outlines specific criteria for these installation requirements of lighting components, including the precise measurement of various dimensions to ensure optimal visibility and safety. Among these dimensional requirements, the dimension 'E' i.e., the “distance between the outer edges of the machine and the illuminating surface of the lighting device” plays a critical role in the performance of vehicle lighting systems. Traditional methods of measuring this dimension, such as using a measuring tape and long straight rod, in another method Using Rope, Plumb and Measuring tape have limitations in terms of precision and consistency due to machine size and shape. This paper presents a method development approach utilizing a 3-Dimensional planar laser for measuring dimension 'E' in Construction Equipment Vehicles (CEVs). Measurement through the planar laser method is found to offer significantly higher accuracy compared to conventional measuring techniques, particularly when applied to the complex shapes and sizes of CEV’s such as Motor Graders, Wheel Loaders and Backhoe Loaders. This approach not only enhances the measurement accuracy but also improves the efficiency of the testing process. The paper discusses the methodologies, results, comparison of 3 measuring methods and potential applications of Planar laser in the context of IS/ISO 12509:2004 & IS/ISO 12509:2023, offering a promising alternative method for future testing and certification of Construction Equipment Vehicle’s lighting systems.
High-power fiber lasers have become increasingly indispensable tools in automotive manufacturing over the past two decades. They are now widely deployed in welding and brazing applications for body-in-white, powertrains, engine components, and more.
Advanced Navigation Sydney, Australia
Since the advent of laser-based imaging techniques in the early 2000s, image acquisition has faced a fundamental challenge: the imaging speed and signal averaging was directly tied to the firing rate of the laser. Because a minimum of one laser pulse generates a single data point, traditional flashlamp-based lasers operating at relatively low repetition rates were constrained in their ability to capture fine spatial or temporal detail quickly. For applications requiring real-time analysis or high-resolution mapping, these limitations often reduced the practicality of otherwise powerful imaging technologies.
NASA’s Glenn Research Center has developed a method of using entangled-photon pairs to produce highly secure mobile communications that require mere milliwatts of power. Conventional gas Argon-ion laser sources are too large, expensive, and power-intensive to use in portable applications. By contrast, Glenn’s patented optical quantum communication method produces entangled-photon pairs approximately a million times more efficiently than conventional sources, in a system that is small and light enough to be portable.
Artificial intelligence systems like ChatGPT are notorious for being power-hungry. To tackle this challenge, a team from the Centre for Optics, Photonics and Lasers (COPL) has come up with an optical chip that can transfer massive amounts of data at ultra-high speed. As thin as a strand of hair, this technology offers unrivaled energy efficiency.
Metabolic imaging is a noninvasive method that enables clinicians and scientists to study living cells using laser light, which can help them assess disease progression and treatment responses. But light scatters when it shines into biological tissue, limiting how deeply it can penetrate and hampering the resolution of captured images.
Researchers in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Vienna University of Technology (TU Wien) have invented a new type of tunable semiconductor laser that combines the best attributes of today’s most advanced laser products, demonstrating smooth, reliable, wide-range wavelength tuning in a simple, chip-sized design.
Medical tubing is an essential component of countless healthcare applications, from intravenous (IV) and oxygen lines to catheters and diagnostic equipment. These tubes, often made of clear flexible polymers, must be produced to exacting standards: free of contaminants, strong under pressure, and biocompatible. However, the joining process to connect these tubes can introduce significant manufacturing challenges.
Researchers have developed a 3D microprinted sensor for highly sensitive on-chip biosensing. The sensor, which is based on a polymer whispering-gallerymode microlaser, opens new opportunities for developing high-performance, cost-effective lab-on-a-chip devices for early disease diagnosis.
Researchers have demonstrated a new technique that uses lasers to create ceramics that can withstand ultra-high temperatures, with applications ranging from nuclear power technologies to spacecraft and jet exhaust systems. North Carolina State University, Raleigh, NC A new technique that leverages the concept of sintering, can be used to create ceramic coatings, tiles or complex three-dimensional structures, which allows for increased versatility when engineering new devices and technologies. “Sintering is the process by which raw materials - either powders or liquids - are converted into a ceramic material,” says Cheryl Xu, co-corresponding author of a paper on this research and a Professor of Mechanical and Aerospace Engineering at North Carolina State University (NCSU). “For this work, we focused on an ultrahigh temperature ceramic called hafnium carbide (HfC). Traditionally, sintering HfC requires placing the raw materials in a furnace that can reach temperatures of at least 2,200 degrees Celsius - a process that is time-consuming and energy intensive.
Despite all the technological evolution in navigation, waters just off coastal shores around the globe have remained a black box. That is, until researchers from The University of Texas at Austin and Oregon State University developed a new technology that uses satellites in space to map out these tricky areas.
A new technique that leverages the concept of sintering, can be used to create ceramic coatings, tiles or complex three-dimensional structures, which allows for increased versatility when engineering new devices and technologies.
A pacemaker is a small device that helps control your heartbeat so you can return to your normal life. It has three main parts: a pulse generator that creates electrical signals, a controller-monitor that manages these signals, and leads that deliver the signals to the heart. One key benefit of the pacemaker is its strong titanium casing. Titanium is very strong and lightweight, and it is biocompatible, meaning it works well with the body without causing harmful reactions. This metal is highly resistant to corrosion, which helps keep the casing intact and protective even when exposed to bodily fluids.
The Department of Defense (DoD) is developing technology for satellites to communicate via lasers. Laser communications could transmit data faster and more securely than traditional radio frequency communications. DoD has made progress in developing this technology, but it has also faced delays and other issues-and hasn't fully demonstrated that it works in space. Despite these challenges, DoD plans to continue to develop and launch hundreds of satellites worth billions of dollars that require the use of laser communications.
Researchers have developed a new type of sensor platform using a gold nanoparticle array. The sensor is made up of a series of gold disk-shaped nanoparticles on a glass slide. When an infrared laser is pointed at a precise arrangement of the particles, they start to emit unusual amounts of ultraviolet (UV) light.
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