Journal articles on the topic 'Lasers'
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1
Pinto, Ana M. R., and Manuel Lopez-Amo. "All-fiber lasers through photonic crystal fibers." Nanophotonics 2, no. 5-6 (December 16, 2013): 355–68. http://dx.doi.org/10.1515/nanoph-2013-0026.
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AbstractA review on all-fiber lasers based on photonic crystal fibers is presented. Photonic crystal fibers present improved features beyond what conventional optical fibers can offer. Due to their geometric versatility, photonic crystal fibers can present special properties and abilities which can lead to enhanced lasing structures. A brief description of photonic crystal fibers and fiber laser’s properties is presented. All-fiber laser structures developed using photonic crystal fibers are described and divided in two groups, depending on the cavity topology: ring cavity fiber lasers and linear cavity fiber lasers. All-fiber lasers applications in the photonic crystal fiber related sensing field are described.
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Nemova, Galina. "Brief Review of Recent Developments in Fiber Lasers." Applied Sciences 14, no. 6 (March 10, 2024): 2323. http://dx.doi.org/10.3390/app14062323.
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This review covers the recent achievements in high-power rare earth (RE)-doped fiber lasers, Raman fiber lasers, and Brillouin fiber lasers. RE-doped fiber lasers have many applications such as laser cutting, laser welding, laser cleaning, and laser precision processing. They operate in several wavelength ranges including 1050–1120 nm (ytterbium-doped fiber lasers), 1530–1590 nm (erbium- and erbium–ytterbium-doped fiber lasers), and 1900–2100 nm (thulium- and holmium-doped fiber lasers). White spaces in the wavelength spectrum, where no RE-doped fiber lasers are available, can be covered by Raman lasers. The heat power generated inside the laser active medium due to the quantum defect degrades the performance of the laser causing, for example, transverse-mode instability and thermal lensing. It can even cause catastrophic fiber damage. Different approaches permitting the mitigation of the heat generation process are considered in this review. Brillouin fiber lasers, especially multiwavelength Brillouin fiber lasers, have several important applications including optical communication, microwave generation, and temperature sensing. Recent progress in Brillouin fiber lasers is considered in this review.
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Yan, Senlin. "Controlling two chaotic lasers via OD-DCF." ITM Web of Conferences 47 (2022): 03003. http://dx.doi.org/10.1051/itmconf/20224703003.
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We present a novelty optoelectronic delay double-cross-feedback (OD-DCF) scheme to control two chaotic lasers based on coupled lasers. We design out the OD-DCF technical solution to convert two lights from two lasers into two photocurrents by two photo-detectors, and then the delay photocurrents are cross-fed back to each other’s lasers respectively to suppress two chaotic oscillations and guide two laser’s dynamics behaviours, respectively. By adjusting the feedback levels and delayed time of OD-DCF, two lasers can obtain chaos-control and show all kinds of dynamics behaviours. We find that chaotic oscillation behaviours of two lasers are suppressed into a stable state and different quasi-cycle states, such as a cycle-one, cycle-two, a cycle-three, a cycle-four, and other quasi-cycle states. We find also that two movement behaviours of two lasers can be controlled to lead to two different cycle-double states. The results prove that the control of two chaotic lasers can be effectively realized via OD-DCF. It is very helpful for our studies of control science, nonlinear optics, chaos, and laser.
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Kwaśna, Magdalena, Paulina Cłapińska, Zuzanna Piosik, Kamila Barysz, Iga Dubiec, Adam Bęben, and Iwona Ordyniec-Kwaśnica. "Intraoral Applications of Lasers in the Prosthetic Rehabilitation with Fixed Partial Dentures—A Narrative Review." Dentistry Journal 12, no. 6 (May 31, 2024): 164. http://dx.doi.org/10.3390/dj12060164.
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Laser, an acronym for Light Amplification by Stimulated Emission of Radiation, is a powerful tool with diverse applications in modern dentistry. It emits monochromatic, coherent light resulting from photon-induced chain reactions. Available dental lasers include diode, argon, Er,Cr:YSGG, Er:YAG, Nd:YAG, and CO2. The unique property of these lasers, allowing them to be effectively used on both soft and hard tissues based on the operational parameters, positions them as particularly suited for a wide range of dental procedures. Compared to traditional methods, lasers offer advantages such as improved hemostasis and quicker wound healing. Such benefits stress the shift towards laser technology in dental treatment. In the realm of dental prosthodontics, which focuses on esthetics, functionality, and the physiological aspects of dental prostheses, lasers provide promising outcomes. Among the prosthetic options, fixed partial dentures stand out for their ability to mimic natural teeth, offering both esthetic and functional features, leading to satisfactory long-term outcomes if managed properly. This review paper delves into the specific application of laser technology in the context of prosthetic rehabilitation involving fixed partial dentures. By investigating intraoral laser procedures, it contributes to understanding laser’s role in improving patients’ satisfaction and clinical efficiency in this field.
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Nemova, Galina. "Radiation-Balanced Lasers: History, Status, Potential." Applied Sciences 11, no. 16 (August 17, 2021): 7539. http://dx.doi.org/10.3390/app11167539.
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The review of history and progress on radiation-balanced (athermal) lasers is presented with a special focus on rare earth (RE)-doped lasers. In the majority of lasers, heat generated inside the laser medium is an unavoidable product of the lasing process. Radiation-balanced lasers can provide lasing without detrimental heating of laser medium. This new approach to the design of optically pumped RE-doped solid-state lasers is provided by balancing the spontaneous and stimulated emission within the laser medium. It is based on the principle of anti-Stokes fluorescence cooling of RE-doped low-phonon solids. The theoretical description of the operation of radiation-balanced lasers based on the set of coupled rate equations is presented and discussed. It is shown that, for athermal operation, the value of the pump wavelength of the laser must exceed the value of the mean fluorescence wavelength of the RE laser active ions doped in the laser medium. The improved purity of host crystals and better control of the transverse intensity profile will result in improved performance of the radiation-balanced laser. Recent experimental achievements in the development of radiation-balanced RE-doped bulk lasers, fibre lasers, disk lasers, and microlasers are reviewed and discussed.
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Parkprom, P., N. Chattrapiban, P. Sompet, and N. Thaicharoen. "Laser linewidth measurement using beat-note technique." Journal of Physics: Conference Series 2653, no. 1 (December 1, 2023): 012081. http://dx.doi.org/10.1088/1742-6596/2653/1/012081.
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Abstract Lasers play a crucial role in quantum and atomic physics experiments. To prepare atoms in a desired quantum state, these lasers must possess specific properties, including tunability and a narrow spectral linewidth. In this study, we construct and employ an external cavity diode laser to prepare cold rubidium atoms. We control the laser’s stability using an electronic system and evaluate its performance by measuring the spectral linewidth through the beat signal technique. The measurement indicates a linewidth narrower than 1 MHz, which makes the laser suitable for subsequent experiments. Finally, we adjust the laser frequency to match the rubidium transition frequency between states 5S 1/2, F = 2 ↔ 5P 3/2, F′ = 2, and successfully utilizing the laser to prepare cold rubidium atoms in a magneto-optical trap.
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Zivkovic, Slavoljub, Larisa Blazic, and Mila Kolar. "Lasers in dentistry." Serbian Dental Journal 51, no. 3 (2004): 146–52. http://dx.doi.org/10.2298/sgs0403146z.
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Lasers and laser technology is now used in many medical and dental indications. The aim of this study was to demonstrate many excellent points that should be considered by the dentist who is contemplating the use of lasers in dental practice. The interaction of laser radiation on soft tissue enables dry and bloodless surgery, minimal postoperative swelling and scarring, and minimal postoperative pain. Lasers for hard tisues encourage efficient diagnosis of caries and improve the resistence of dental enamel to caries, laser etching of enamel, cavity preparations, photopolymerization of composite resin and sterilization of the root canal system. All staff who are involved in using lasers must be trained with regard to treatment protocols and safety measures. All personnel and the patient must wear safety-approved glasses.
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Huang, Qin, Zucen Li, Ping Lyu, Xuedong Zhou, and Yi Fan. "Current Applications and Future Directions of Lasers in Endodontics: A Narrative Review." Bioengineering 10, no. 3 (February 26, 2023): 296. http://dx.doi.org/10.3390/bioengineering10030296.
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The utilization of lasers has been regarded as a novel technique for the purposes of clinical use in the dental field. Recently, numerous studies have been conducted on the potential applications of laser therapy in endodontics. Moreover, due to their ablation, penetrability, and disinfection capabilities, lasers have performed well with respect to endodontic treatments, including root canal treatment, vital pulp therapy (pulp capping and pulpotomy), dentinal hypersensitivity treatment, and management of dental pain related to pulp and periradicular disease. In particular, the superiorities of laser-aided pulp therapy are emphasized through condensed clinical controlled trials, and histological studies, in this review. Moreover, the ingenious use of laser applications with respect to aiding in the acceleration of root development and the extraction of foreign matters (i.e., broken files and fiber posts) in canals has quickly become the cutting-edge trend of current research. This review offers a summary and discussion of the current literature on all the aforementioned laser applications. Moreover, the characteristics of laser devices, including erbium lasers, neodymium-doped lasers, CO2 lasers, and diode lasers, are detailed and discussed here, providing useful references for laser application in endodontics. We also focus on the different wavelengths with respect to the lasers that are applied in endodontics. High-power lasers perform well as operative instruments; in addition, low-level lasers lead to the regulation of pulp inflammation, and the promotion of pulp healing. This narrative review provides a summary of the advanced applications of lasers in conjunction with various devices in the practice of endodontics, and aims to inspire innovative perspectives on lasers in the context of the treatment of dental diseases, especially pulp diseases, in the future.
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AlDomyati, Roaa, Raghad Bajaber, Faisal Alrumi, Maram Alghamdi, Abdulkarim Alharbi, Nasser Alsour, Somaya Alhaf, et al. "The Use of Lasers in Pediatric Dentistry: Applications, Benefits, and Limitations." JOURNAL OF HEALTHCARE SCIENCES 03, no. 10 (2023): 427–35. http://dx.doi.org/10.52533/johs.2023.31009.
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The application of laser technology in pediatric dentistry holds immense promise for improving the quality of care and treatment experiences for young patients. Laser technology offers efficient methods for diagnosing and addressing oral and dental issues in children, encompassing both soft and hard tissues. Research indicates that the use of lasers in restorative, pulpal, and surgical procedures enhance children's cooperation and results in better care quality. Different kinds of lasers, including laser fluorescence (LF), argon lasers, erbium lasers, and CO2 lasers, are used in a range of dental applications, such as identifying, preventing, and treating cavities, as well as performing various other dental procedures. Laser technology also offers benefits in endodontics, soft tissue applications, trauma management, pain relief, and orthodontics. However, the implementation of lasers requires specialized training, initial investment costs, and careful infection control measures. Despite these limitations, lasers hold the potential to become a standard approach in pediatric dentistry, revolutionizing the way oral and dental issues are diagnosed and treated in young patients.
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Neauport, Jérôme, and Sebastien Vermersch. "Le laser Megajoule." Photoniques, no. 126 (2024): 22–26. http://dx.doi.org/10.1051/photon/202412622.
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Dédié à l’étude des plasmas denses et chauds au sein du programme de Simulation du CEA DAM, le laser Mégajoule est actuellement l’un des lasers les plus énergétiques du monde. Après la mise en route d’une première chaîne laser en 2014, il comprend aujourd’hui 11 chaines lasers (soit 88 faisceaux lasers) délivrant quotidiennement jusqu’à 330 kJ d’énergie sur cible à la longueur d’onde de 351 nm. Nous décrivons le système laser LMJ, les performances atteintes dans sa configuration actuelle, ainsi que les campagnes lasers conduites pour amener l’installation à une énergie de 1.3 MJ, une fois les 22 chaines lasers montées et qualifiées.
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Xia, Hongyan, Chang Hu, Tingkuo Chen, Dan Hu, Muru Zhang, and Kang Xie. "Advances in Conjugated Polymer Lasers." Polymers 11, no. 3 (March 7, 2019): 443. http://dx.doi.org/10.3390/polym11030443.
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This paper provides a review of advances in conjugated polymer lasers. High photoluminescence efficiencies and large stimulated emission cross-sections coupled with wavelength tunability and low-cost manufacturing processes make conjugated polymers ideal laser gain materials. In recent years, conjugated polymer lasers have become an attractive research direction in the field of organic lasers and numerous breakthroughs based on conjugated polymer lasers have been made in the last decade. This paper summarizes the recent progress of the subject of laser processes employing conjugated polymers, with a focus on the photoluminescence principle and excitation radiation mechanism of conjugated polymers. Furthermore, the effect of conjugated polymer structures on the laser threshold is discussed. The most common polymer laser materials are also introduced in detail. Apart from photo-pumped conjugated polymer lasers, a direction for the future development of electro-pumped conjugated polymer lasers is proposed.
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Shetty, Sharath Kumar, Cecilia Wilson, Mahesh Kumar Y, and Vijayananda K. Madhur. "Lasers in Orthodontics." Scholars Journal of Dental Sciences 8, no. 7 (August 13, 2021): 224–29. http://dx.doi.org/10.36347/sjds.2021.v08i07.007.
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Laser technique now is widely applied in orthodontic treatment and proved to have many benefits. Soft tissue lasers can be used to perform gingivectomy, frenectomy and surgical exposure of tooth with less bleeding and swelling, improved precision, reduced painand less wound contraction. Other laser applications include enamel etching and bonding andbracket debonding. Lower level lasers have the potential effects of pain control and accelerating tooth movement. Clinicians must be aware of the safety issues and risks associated with laser and receive proper training before the laser treatment is started.
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Wang, Xuefeng, Shihao Sun, Ye Zheng, Miao Yu, Siyuan Li, Yi Cao, and Junlong Wang. "Influence of Pre-Radiation and Photo-Bleaching on the Yb-Doped Fiber Laser Radiated with Gamma-ray." Applied Sciences 13, no. 10 (May 18, 2023): 6146. http://dx.doi.org/10.3390/app13106146.
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To improve the radiation resistance of Yb-doped fiber lasers, we investigate the influence of pre-radiation and photo-bleaching on the gamma-radiated laser’s performance. When the gamma radiation dose is within 10 krad(Si) with a radiation dose rate less than 0.4 rad(Si)/s, compared to the output power of a non-pre-radiated Yb-doped fiber laser, the pre-radiation technique could enhance the radiation resistance against gamma-ray. However, the mode instability threshold was decreased, which was caused by the cumulated radiation-induced attenuation of pre-radiation and radiation. Based on an electronic probe micro-analyzer, the Yb-doped active fiber was Yb-doped aluminophosphosilicate ternary fiber; therefore, the radiated defects were mainly hole-related defects. A laser diode centered at 532 nm was chosen as the photo-bleaching laser source, which could recover 45.2% of the radiated-induced attenuation and increase the mode instability threshold. This work demonstrates the influence of pre-radiation and photo-bleaching on the radiation resistance against the gamma-ray of Yb-doped fiber lasers, which are of significance in the design and fabrication of related fiber lasers.
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Malherbe, C. P. "Lasers: Aspects of effectiveness and safety." South African Journal of Physiotherapy 47, no. 2 (May 31, 1991): 24–27. http://dx.doi.org/10.4102/sajp.v47i2.760.
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The use of laser therapy by physiotherapists has shown a marked increase in popularity over recent years. Effectiveness and safety of lasers is essential. The results of an investigation by the CSIR of some infrared lasers is reported, highlighting, e.g., that all that SAYS laser may not BE laser. New legislation that will ensure that lasers conform with the minimum requirements to be safe and effective products, is discussed. The risk of laser radiation and product/premises licenses as a means of ensuring safe use of lasers, are explained.
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BHATTACHARYA, PALLAB. "TUNNEL INJECTION LASERS." International Journal of High Speed Electronics and Systems 09, no. 04 (December 1998): 847–66. http://dx.doi.org/10.1142/s0129156498000361.
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Carrier heating in conventional quantum well lasers can lead to several deleterious effects and are related to the transport and thermalization characteristics of injected carriers. The properties of a quantum well laser in which the electrons are directly transported to the lasing subband by tunneling is described here. The resulting device — a tunnel injection laser — is shown to have negligible gain compression, superior high-temperature performance, lower Auger recombination and wavelength chirp, and better high frequency modulation characteristics when compared to conventional lasers. All these improvements are attributed to the reduction of hot-carrier population in the active region of the laser. Results are presented here for lasers made with GaAs — and InP — based heterostructure systems.
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Gupta, Aditya K., Kelly A. Foley, and Sarah G. Versteeg. "Lasers for Onychomycosis." Journal of Cutaneous Medicine and Surgery 21, no. 2 (November 5, 2016): 114–16. http://dx.doi.org/10.1177/1203475416677722.
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Many studies that have been recently published investigate the efficacy of laser treatment for onychomycosis. These studies support the current US Food and Drug Administration (FDA) approval of lasers for the ‘temporary increase in clear nail’. Clear nail growth is an important treatment goal for patients; however, many do not realise that laser treatment is not a cure for onychomycosis. The current article briefly reviews why lasers may be theoretically effective in treating onychomycosis and critically reviews published laser studies for onychomycosis in light of the standards employed in drug trials. Treatment regimens, efficacy endpoints, and the unit of analysis (nails vs patients) vary widely among published laser studies. Complete cure, mycological cure, and clinical improvement rates in laser studies are not reported or use such disparate criteria that comparison among studies is not possible. The US FDA has recently published guidelines for the use of medical devices in clinical trial design for onychomycosis. Future laser studies should adopt the FDA’s guidelines to allow for more consistency within the field and focus on the efficacy of lasers as monotherapy for onychomycosis.
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Li, DongCheng. "Femtosecond pulsed laser technology and applications." Theoretical and Natural Science 28, no. 1 (December 26, 2023): 166–73. http://dx.doi.org/10.54254/2753-8818/28/20230347.
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This paper describes femtosecond pulsed laser technology and related applications. The focus is on two core femtosecond pulsed laser technologies: femtosecond pulsed laser generation and amplification. In the generation of femtosecond pulsed lasers, mode-locking techniques, Kerr-lens mode-locking, and semiconductor saturable absorber mirrors are presented; in the amplification of femtosecond pulsed lasers, chirped-pulse amplification and coherent synthesis techniques are presented. This paper analyses the applications of femtosecond pulsed lasers in both the biomedical and manufacturing sectors and gives the development trends as well as the challenges of femtosecond laser technology. Femtosecond lasers are now used in a wide range of applications. Femtosecond pulsed lasers will develop in the directions of high power, miniaturisation, intelligence and precision. Laser tweezers will become the new direction of development in the future.
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FUKUDA, MITSUO. "RELIABILITY OF HIGH POWER PUMP LASERS FOR ERBIUM-DOPED FIBER AMPLIFIERS." International Journal of High Speed Electronics and Systems 07, no. 01 (March 1996): 55–84. http://dx.doi.org/10.1142/s0129156496000049.
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The degradation behavior and the reliability of 980 nm lasers and 1480 nm lasers are reviewed and discussed. In addition, packaging problems for the high power lasers are also discussed from the application viewpoint. For 980 nm lasers the reliability in laser chip is limited mainly by the instability of an interface between the laser material (facet) and the anti-reflecting coating film, and for most 1480 nm lasers the reliability of the laser chip is determined mainly by the instability of a buried heterointerface. These reliability problems have been solved, however, by examining the material properties and improving device fabrication technology. The main packaging problem is a packaging-induced failure (PIF) causing sudden failure in 980 nm lasers sealed in dry N2 or Ar, but packaging problems have also been suppressed or eliminated. The device technology and packaging technology needed to make high power pump laser modules have been established, and erbium-doped fiber amplifiers pumped by these lasers are indispensable components of many optical transmission systems.
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Liu, Bin, Yangfan Jiang, and Haining Ji. "Sensing by Dynamics of Lasers with External Optical Feedback: A Review." Photonics 9, no. 7 (June 27, 2022): 450. http://dx.doi.org/10.3390/photonics9070450.
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External optical feedback (EOF) has great impacts on the properties of lasers. It influences the stable operation of lasers. However, various applications based on lasers with EOF have been developed. One typical example is self-mixing interferometry technology, where modulated steady-state laser intensity is utilized for sensing and measurement. Other works show that laser dynamics can also be used for sensing, and the laser in this case is more sensitive to EOF. This paper reviews the sensing technology that uses the dynamics of lasers with EOF. We firstly introduce the basic operating principles of a laser with EOF and discuss the noise properties of and intensity modification in lasers induced by EOF. Then, sensing applications using laser dynamics are categorized and presented, including sensing by frequency-shifted optical feedback, relaxation oscillation frequency, and dynamics with self-mixing interferometry signals and laser optical chaos. Lastly, we present an analysis of the transient response waveform and spectrum of a laser with EOF, showing its potential for sensing.
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Li, Guanwei. "Research on U-band Fiber Lasers." Highlights in Science, Engineering and Technology 97 (May 28, 2024): 166–71. http://dx.doi.org/10.54097/vvxym768.
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The U-band fiber laser has attracted the attention of many researchers and industry due to its outstanding performance characteristics. U-band fiber laser is a type of laser that operates in the ultraviolet wavelength range, and its research background mainly stems from the demand for ultraviolet lasers in scientific research, medical treatment, material processing, and other fields. However, traditional ultraviolet lasers often use gas laser media, which have large volume, high power consumption, and high maintenance costs, limiting their promotion in practical applications. Therefore, researchers have begun to explore the use of fiber optic technology to achieve miniaturization, efficiency, and stability improvement of ultraviolet lasers. This article provides an overview of the working principle and application fields of U-band fiber lasers and proposes the future development direction of U-wave fiber lasers. Intended to provide useful references for further research on fiber lasers. Through continuous technological innovation and process improvement, this paper promote the further development of U-band fiber laser technology, expand its application areas, improve performance and stability, and promote its widespread application in industrial and scientific research fields.
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Chen, Yu-Cheng, and Ningyuan Nie. "(Invited) micro-Nanoscale Living Lasers for Healthcare Applications." ECS Meeting Abstracts MA2023-01, no. 34 (August 28, 2023): 1915. http://dx.doi.org/10.1149/ma2023-01341915mtgabs.
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Have you imagined of carrying a laser in your cell or body? Lasers are ubiquitous in our daily lives from industry, communication to medicine. The scale of lasers has also shrunk down to micron and nanoscales. As the scale of laser become smaller, the functions of lasers have also been redefined by transforming living biologicals into micro- and nanoscale lasers, so called living lasers. Such tiny lasers could therefore be used to detect or monitor critical chemical or physical signals in living cells or human body with distinctive sensitivity and intensity. In this talk, I will introduce the recent development of biological lasers and showcase how this interdisciplinary technology bridges laser physics and biology to tackle biomedical problems. In the first part, the talk will be focused on its application in detecting cancer and neurological diseases. In the second part, I will introduce how tiny lasers can be transformed with intelligent functions for information encoding and healthcare. This will cover applications including sensing at multiscales in biology, imaging in tissues, tracking and monitoring, as well as biomedical devices. Finally, discussion and outlook will be made on the strategies to pioneer novel on-chip and wearable laser devices for future medical diagnosis and bio-intelligent technology. Figure 1
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S, Rajyalakshmi, Lavanya Jyothi M, Kumari M, Venkata Ganga Yasaswini L, Srivani M, Bhargavi M, Chandrakala K, Supriya K, Dora M V V S, and Asha MD. "Data transmission through lasers." South Asian Journal of Engineering and Technology 12, no. 3 (November 3, 2022): 167–70. http://dx.doi.org/10.26524/sajet.2022.12.54.
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In the current era technology in science has recently attracted owing the advancement of applications in lasers. A project on the applications of the laser introduced. The application part of the laser has been applied by simple laser communication system which evolved in its working with the support of solar panel, differential grating. It also provides the information how the data is transmitted through lasers.
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Meshram, Ishwar, and Kashinath Choudhary. "LASERS IN OPHTHALMOLOGY." International Journal of Advanced Research 11, no. 01 (January 31, 2023): 781–86. http://dx.doi.org/10.21474/ijar01/16082.
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This article reviews the principle uses of ophthalmic lasers, providing historical background with an emphasis on new applications and areas of investigation. Ophthalmic photocoagulation was the first medical laser application and has restored or maintained vision in millions of people. The use of ophthalmic lasers is becoming increasingly widespread, with most eye departments now having at least one type of laser. Many patients are treated withlasers and many more request such treatment, even when it is not indicated. The indications for ophthalmic lasers are constantly changing as experience with established treatments increases and new equipment is developed.
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Dmytryszyn, Mark, Matthew Crook, and Timothy Sands. "Preparing for Satellite Laser Uplinks and Downlinks." Sci 2, no. 1 (March 18, 2020): 16. http://dx.doi.org/10.3390/sci2010016.
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The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, even lasers as weapons (e.g., Airborne Laser). Lasers in support of telecommunications is also not new. The use of laser light in fiber optics shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers rather than traditional radio frequency sources for satellite uplink and downlink signal carriers, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploitation (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt.
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Dmytryszyn, Mark, Matthew Crook, and Timothy Sands. "Lasers for Satellite Uplinks and Downlinks." Sci 2, no. 2 (June 12, 2020): 44. http://dx.doi.org/10.3390/sci2020044.
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The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, even lasers as weapons (e.g., Airborne Laser). Lasers in support of telecommunications is also not new. The use of laser light in fiber optics shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers rather than traditional radio frequency sources for satellite uplink and downlink signal carrier, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploitation (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt.
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Dmytryszyn, Mark, Matthew Crook, and Timothy Sands. "Lasers for Satellite Uplinks and Downlinks." Sci 2, no. 3 (September 9, 2020): 71. http://dx.doi.org/10.3390/sci2030071.
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The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, even lasers as weapons (e.g., Airborne Laser). Lasers in support of telecommunications is also not new. The use of laser light in fiber optics shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers rather than traditional radio frequency sources for satellite uplink and downlink signal carrier, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploitation (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt.
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Dmytryszyn, Mark, Matthew Crook, and Timothy Sands. "Lasers for Satellite Uplinks and Downlinks." Sci 3, no. 1 (January 4, 2021): 4. http://dx.doi.org/10.3390/sci3010004.
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The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, and even lasers as weapons (e.g., Airborne Laser). Lasers in the support of telecommunications is also not new. The use of laser light in fiber optics has shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform the U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers, rather than traditional radio frequency sources for satellite uplink and downlink signal carriers, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, and large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploit (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt.
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Nalcaci, Ruhi, and Serpil Cokakoglu. "Lasers in orthodontics." European Journal of Dentistry 07, S 01 (September 2013): S119—S125. http://dx.doi.org/10.4103/1305-7456.119089.
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ABSTRACTMany types of dental lasers are currently available that can be efficiently used for soft and hard tissue applications in the field of orthodontics. For achieving the desired effects in the target tissue, knowledge of laser characteristics such as power, wavelength and timing, is necessary. Laser therapy is advantageous because it often avoids bleeding, can be pain free, is non-invasive and is relatively quick. The high cost is its primary disadvantage. It is very important to take the necessary precautions to prevent possible tissue damage when using laser dental systems. Here, we reviewed the main types and characteristics of laser systems used in dental practice and discuss the applications of lasers in orthodontics, harmful effects and laser system safety.
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ANDREASEN, JONATHAN, NICOLAS BACHELARD, SHIVAKIRAN B. N. BHAKTHA, HUI CAO, PATRICK SEBBAH, and CHRISTIAN VANNESTE. "PARTIALLY PUMPED RANDOM LASERS." International Journal of Modern Physics B 28, no. 05 (February 6, 2014): 1430001. http://dx.doi.org/10.1142/s0217979214300011.
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Conventional lasers consist of two components: a gain material that is pumped in order to provide amplification of light and a cavity to provide feedback. Random lasers replace the traditional laser cavity with a random, multiple-scattering medium. This can give rise to complex lasing behavior, such as unpredictable multidirectional and multifrequency output. Controlling these systems has proved difficult and, until now, has consisted of material and structural manipulations. In random lasers, the most common pumping mechanism is an optical field, which can be applied uniformly or partially across the scattering medium. Partial pumping, referring to the restricted spatial extent of the pump applied to the gain material, is therefore quite ubiquitous in such systems. In contrast to conventional lasers, however, the impact of partial pumping can be significant in random lasers as a subset of the scattering medium is probed. In this review, we discuss state-of-the-art investigations of partially pumped random lasers. Numerical and experimental investigations of how even a simple spot profile of the pump can dramatically alter random laser output are presented. First, the simple case of partial pumping in strongly scattering systems where laser modes are spatially confined is described. Then the most common but more difficult case of weakly scattering random lasers is considered. Here, modes are spatially extended, forcing greater mode interaction and making the random laser output more difficult to predict. Finally, we review recent works that show how the pumping degree of freedom allows a general increase in control over random lasers.
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Stelmakh, N. "Sub-Picosecond Mode-Locked Laser Diodes." International Journal of High Speed Electronics and Systems 08, no. 03 (September 1997): 525–46. http://dx.doi.org/10.1142/s0129156497000196.
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Recent experiments have shown that laser diodes are capable generating nulses as short as 160 fs, thus approaching the performance of more conventional femtosecond lasers such as Tilsapphire lasers or dye lasers. Regular progress is also accomplished in terms of power and energy efficiency or spectral and spatial brightness with the development of novel semiconductor laser structures. In this paper, we review decisive improvements which have placed laser diodes in category of sub-picosecond lasers. A number of experimental results are used to illustrate the specific characteristics of short-pulse laser diodes as compared to other laser systems. The effects of dispersion and phase modulation are discussed on a basis of theoretical model of chirp mode locking.
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Bertling, Karl, Xiaoqiong Qi, Thomas Taimre, Yah Leng Lim, and Aleksandar D. Rakić. "Feedback Regimes of LFI Sensors: Experimental Investigations." Sensors 22, no. 22 (November 21, 2022): 9001. http://dx.doi.org/10.3390/s22229001.
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In this article, we revisit the concept of optical feedback regimes in diode lasers and explore each regime experimentally from a somewhat unconventional point of view by relating the feedback regimes to the laser bias current and its optical feedback level. The results enable setting the operating conditions of the diode laser in different applications requiring operation in different feedback regimes. We experimentally explored and theoretically supported this relationship from the standard Lang and Kobayashi rate equation model for a laser diode under optical feedback. All five regimes were explored for two major types of laser diodes: inplane lasers and vertical-cavity surface emitting lasers. For both lasers, we mapped the self-mixing strength vs. drive current and feedback level, observed the differences in the shape of the self-mixing fringes between the two laser architectures and a general simulation, and monitored other parameters of the lasers with changing optical feedback.
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Akshay Jaiswal, Anuja Ikhar, Pradnya Nikhade, Manoj Chandak, Rushikesh Bhonde, Samrudhi Kathod, Saurabh Rathi, and Kajol Relan. "Lasers in Endodontic: A review." International Journal of Research in Pharmaceutical Sciences 12, no. 1 (January 6, 2021): 150–53. http://dx.doi.org/10.26452/ijrps.v12i1.3970.
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Since the development of ruby laser by Maiman in 1960 & application of laser for endodontics by Weichman in 1971, a variety of papers on potential applications for lasers in endodontics have been published. Lasers have been a significant advancement in the field of endodontics. Be it effective cleaning, root canal treatment, surgery etc. The lateral accessory canals and anatomical complexities have been a restraint in root canal procedure, for such cases lasers have been introduced to simplify the process & have good clinical results. As there has been a boon in the improvement of laser techniques, many latest lasers having a broad array of characteristics is accessible and can also be helpful in several areas related to dentistry. When compared with conventional techniques, laser treatments has been proven to be more advantageous. The purpose of this article is to summarize laser applications in endodontics, including their use in pulp diagnosis, dentinal hypersensitivity, pulp capping and pulpotomy, sterilization of root canals, root canal shaping & obturation & apicectomy. This article reviews the role of lasers in endodontics since the early 1970s & summarizes what future may hold for endodontics. With the potential availability of many new laser wavelengths and modes, much interest is developing in this promising field.
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Račiukaitis, Gediminas, and Kristina Ananičienė. "A small country with high ambitions." PhotonicsViews 20, no. 4 (August 2023): 34–36. http://dx.doi.org/10.1002/phvs.202300031.
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AbstractStarting from fundamental research just after the discovery of the laser, the Lithuanian laser industry is celebrating forty years since the first commercial company, Eksma, was established in 1983 to produce picosecond lasers. The sector has grown into a fully self‐sustaining ecosystem, providing optics, ultrashort‐pulse lasers, laser technology and systems to the global market. Today, lasers and optics are one of Lithuania's strongest and highest value‐added industrial sectors.
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Castelo‐Porta, Antonio. "“The trick is to find out where those opportunities are”." PhotonicsViews 20, no. 4 (August 2023): 23–25. http://dx.doi.org/10.1002/phvs.202370405.
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Ruksasakchai, P., C. E. Cowdell, L. Sanchez, M. Weyland, and M. F. Andersen. "A microcontroller based self-locking laser system." Review of Scientific Instruments 93, no. 4 (April 1, 2022): 043008. http://dx.doi.org/10.1063/5.0087399.
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We present a self-locking laser system that does not require operator interventions. The system automatically finds a desired atomic transition and subsequently locks to it. Moreover, it has the ability to automatically detect if the laser is out of lock and activate the re-locking process. The design was implemented on two different diode lasers, a distributed Bragg reflector (DBR) diode laser and a Fabry Perot (FP) diode laser, used as a repump laser for a magneto-optical trap in a laser cooling experiment and a Raman laser for a four-level Raman transition experiment, respectively. The design relies on frequency modulation transfer spectroscopy to obtain a sub-Doppler atomic spectrum of rubidium-85. This spectrum is then demodulated to obtain zero-crossing linear slopes at the exact points of each atomic and crossover transition. The frequency modulation, the signal analysis, and the automatic locking and re-locking of the lasers are all implemented using an Arduino Due microcontroller. The lock loop has a bandwidth of 7 kHz. The lasers used for the design are characterized, and the robustness of the lock is analyzed. The achieved linewidths of DBR and FP lasers are 1.4 and 5.5 MHz, respectively. The frequency drifts of both lasers are a few 100 kHz over a course of days. The capture range of the locking system is up to 4.9 GHz for the DBR laser and 725 MHz for the FP laser. Both lasers performed well under actual experimental conditions.
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Chaisrimaneepan, Nattanicha. "Pitfalls in Laser-Based Device Tattoo Removal: A Literature Review." SKIN The Journal of Cutaneous Medicine 8, no. 2 (March 18, 2024): 1384–95. http://dx.doi.org/10.25251/skin.8.2.4.
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Laser therapy has been popular and widely used for tattoo removal. Basic principles for utilizing lasers in tattoo removal for different types and colors of tattoos are required to minimize and avoid unwanted side effects. Appropriate parameters of lasers are not the only keys to successful laser removal treatment. In this review, common pitfalls in removing tattoos with lasers are discussed. Several factors should be taken into consideration and realistic goals should be discussed at the first encounter with patients. Non-ablative lasers may apply to a simple tattoo without any cutaneous reaction while ablative lasers are better for traumatic tattoos. Laser is not always the best option for tattoo removal in some circumstances and other measures can be considered for the best interest of patients and outcome.
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Liu, Guanghui, Di Gu, Jingliang Liu, Yan Fang, Jiaqi Liu, Zhaoyang Li, Kuofan Cui, and Xinyu Chen. "Development of the 2.7 μm to 3 μm Erbium-Doped Laser." Crystals 13, no. 10 (October 10, 2023): 1471. http://dx.doi.org/10.3390/cryst13101471.
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The 3 μm wavelength band laser is located on the strong absorption peak of water and the atmospheric transmission window. The 3 μm laser with high single pulse energy is used in medical treatment for cutting soft tissues and bones during surgery. It is used as a pump source for optical parametric oscillators, and Fe lasers can realize 3~5 μm or 8~14 μm laser output, which has an irreplaceable role in certain areas (e.g., optoelectronic countermeasures, LIDAR, atmospheric monitoring, etc.). Commercial semiconductor-pumped Er lasers are capable of achieving 3 μm laser output of 600 mJ with the maturation of a 970 nm semiconductor laser. The conversion efficiency is significantly improved. However, the energy is lower than a flash-lamp-pumped Er laser. There are still serious crystal thermal effects and an inefficient conversion process. In this paper, the energy-level systems of 3 μm Er-doped lasers are discussed. A summary of the current state of research on Er lasers using different matrices and the commercialization of Er-doped lasers with wavelengths ranging from 2.7 μm to 3 μm is also provided. Several technical means are given to enhance laser performance. Furthermore, the development of Er-doped solid-state lasers with wavelengths between 2.7 and 3 μm is envisaged in the near future.
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Mote, Nilesh, N. G. Toshniwal, Shubhangi Mani, Ashwini Nalkar, and Vishal Dhanjani. "Lasers in Orthodontics – A Review." Orthodontic Journal of Nepal 10, no. 3 (December 31, 2020): 62–65. http://dx.doi.org/10.3126/ojn.v10i3.35498.
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Introduction: In past few years, there is huge improvement in orthodontics. Different innovation in orthodontics made the procedure easier and less time consuming. Application of laser is one of them. Many types of dental lasers are currently available that can be efficiently used for soft and hard tissue applications in the field of orthodontics. Two types of lasers are there. One is hard tissue laser, and another is soft tissue laser. Laser therapy is advantageous because it often avoids bleeding, can be pain free, is non‑invasive and is relatively quick. The high cost is its primary disadvantage. The purpose of this article is to provide an overview regarding safe and proper use of soft-tissue lasers in orthodontics
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Heidari, Elham, Hamed Dalir, Moustafa Ahmed, Volker J. Sorger, and Ray T. Chen. "Hexagonal transverse-coupled-cavity VCSEL redefining the high-speed lasers." Nanophotonics 9, no. 16 (October 15, 2020): 4743–48. http://dx.doi.org/10.1515/nanoph-2020-0437.
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AbstractVertical-cavity surface-emitting lasers (VCSELs) have emerged as a vital approach for realizing energy-efficient and high-speed optical interconnects in the data centers and supercomputers. Indeed, VCSELs are the most suitable mass production lasers in terms of cost-effectiveness and reliability. However, there are still key challenges that prevent achieving modulation speeds beyond 30s GHz. Here, we propose a novel VCSEL design of a hexagonal transverse-coupled-cavity adiabatically coupled through a central cavity. Following this scheme, we show a prototype demonstrating a 3-dB roll-off modulation bandwidth of 45 GHz, which is five times greater than a conventional VCSEL fabricated on the same epiwafer structure. This design harnesses the Vernier effect to increase the laser’s aperture and therefore is capable of maintaining single-mode operation of the laser for high injection currents, hence extending the dynamic roll-off point and offering increases power output. Simultaneously, extending both the laser modulation speed and output power for this heavily deployed class of lasers opens up new opportunities and fields of use ranging from data-comm to sensing, automotive, and photonic artificial intelligence systems.
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Yan, Sen Lin. "Master-Slave-Parallel Chaotic Synchronization in Class-C Lasers by Controlling the Pump." Applied Mechanics and Materials 590 (June 2014): 166–70. http://dx.doi.org/10.4028/www.scientific.net/amm.590.166.
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A system of “master-slave-parallel” chaotic synchronization in class-C lasers is presented. Lasing from a chaotic class-C laser as a master is changed to photon-electricity to drive to modulate the pumps of two parallel of slave class-C lasers so that the two slave lasers can be controlled to the chaotic state of the master laser. “Master-slave” chaotic synchronization can be achieved. At the same time, chaotic synchronization is gradually achieved between the two slave lasers after a few desynchronous oscillations. Lastly, “master-slave-parallel” chaotic synchronization is achieved. Chaotic synchronization process is analyzed in detail. Synchronization principle of the three chaotic lasers is deduced.
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He, Zhicong, Lixiang Lei, Shaojiang Lin, Shaoan Tian, Weilan Tian, Zaiyuan Yu, and Fang Li. "Metal Material Processing Using Femtosecond Lasers: Theories, Principles, and Applications." Materials 17, no. 14 (July 9, 2024): 3386. http://dx.doi.org/10.3390/ma17143386.
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Metal material processing using femtosecond lasers is a useful technique, and it has been widely employed in many applications including laser microfabrication, laser surgery, and micromachining. The basic mechanisms of metal processing using femtosecond lasers are reviewed in this paper and the characteristics and theory of laser processing are considered. In addition to well-known processes, the recent progress relating to metals processing with femtosecond lasers, including metal material drilling, metal ablation thresholds, micro/nano-surface modification, printed circuit board (PCB) micromachining, and liquid metal (LM) processing using femtosecond lasers, is described in detail. Meanwhile, the application of femtosecond laser technology in different fields is also briefly discussed. This review concludes by highlighting the current challenges and presenting a forward-looking perspective on the future of the metal laser processing field.
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Yue, Ziqian, Li Cao, Dawei Wang, Ziqi Yuan, Jiajie Li, Baodong Chen, and Yueyang Zhai. "Accurate Modeling of Distributed Bragg Reflector Laser Power and Wavelength Using Gaussian Process Regression." Photonics 10, no. 2 (February 12, 2023): 193. http://dx.doi.org/10.3390/photonics10020193.
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Distributed Bragg reflector (DBR) lasers are widely used in many physics experiments. However, regarding the power and frequency control of DBR lasers, obtaining complete and accurate output characteristics is challenging due to the need for general and accurate quantitative models. In this study, we propose and validate a method based on Gaussian process regression to quickly and accurately establish the DBR laser output power and wavelength model. Two models are developed to describe the output power, wavelength, input current, and temperature. The findings show that our power model explains the laser’s power change from the current threshold to the maximum value more precisely, with a root mean square error (RMSE) of 0.16921 mW, less than one-fifth of that of the classic power model. Moreover, our wavelength model is feasible for accurately describing the laser wavelength with a RMSE of 4×10−4 nm. This study can improve DBR laser power and frequency control efficiency and precision.
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Wang, Ya, Shengbao Zhan, Wenran Le, Qinghai Liu, Yuting Wang, Lin Zou, and Zhifeng Deng. "Comparison of Output Performance of Tunable Lasers with Two Different External Cavities." International Journal of Optics 2022 (August 17, 2022): 1–7. http://dx.doi.org/10.1155/2022/7829924.
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Based on the simplified model of the tunable fiber laser system, the tuning performance of the laser was analyzed. Two kinds of tunable setups were established, which are the configurations with an external cavity and the configuration of the Littrow cavity. The tuning output characteristics experimentally were analyzed by means of setups. The simulation gives the output efficiency of two tunable lasers as 40% and 30%. In the experiment, the measured slope efficiency of the two lasers was 24% and 18.3%, and the tunable range of the two lasers was 32 nm and 40 nm, respectively. Both lasers could achieve laser output with good beam quality.
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Sui, Yuan, Mingheng Yuan, Zhenao Bai, and Zhongwei Fan. "Recent Development of High-Energy Short-Pulse Lasers with Cryogenically Cooled Yb:YAG." Applied Sciences 12, no. 8 (April 7, 2022): 3711. http://dx.doi.org/10.3390/app12083711.
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High-power solid-state lasers are among the hot research directions at the forefront of laser research and have major applications in industrial processing, laser-confined nuclear fusion, and high-energy particle sources. In this paper, the properties of Yb:YAG and Nd:YAG crystals as gain media for high-power solid-state lasers were briefly compared, according to the results of which Yb:YAG crystals are more suitable for high-power applications. Then, the effects of the thermodynamic and spectral properties of Yb:YAG crystals with temperature were analyzed in detail, and it was shown that the laser beams amplified by the cryogenically cooled Yb:YAG crystals could have higher beam quality, higher pump absorption efficiency, lower pump threshold, and higher gain. The change in properties of Yb:YAG crystal at low temperature makes it more suitable as a gain medium for high-power lasers. Subsequently, two types of kilowatt-class lasers using cryogenically cooled Yb:YAG crystals as gain media are introduced—100 J, 10 Hz nanosecond lasers and 1 J, 1 kHz picosecond lasers. Their configuration, main parameters, and typical output results were analyzed. Finally, future directions in the development of cryogenically cooled Yb:YAG lasers are discussed.
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Zayneeva, Roza Shamilevna, Aygul' Kamilovna Gil'mutdinova, Igor' Olegovich Zolotovskiy, Anna Vyacheslavovna Khokhlova, Valeriya Aleksandrovna Ribenek, and Tat'yana Petrovna Gening. "LASER ADJUVANTS: KEY FEATURES AND SPECIFICITY." Ulyanovsk Medico-biological Journal, no. 4 (December 26, 2022): 93–108. http://dx.doi.org/10.34014/2227-1848-2022-4-93-108.
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Increasing the vaccine effectiveness and the search for new adjuvants that directly influence immunocompetent cells and stimulate the development of a pronounced adaptive immune response remain significant problems for modern medicine. Currently, aluminum salts and other chemicals with certain side effects are used as adjuvants. Therefore, it is relevant to search for other methods to increase vaccine effectiveness while reducing its toxic effect on the patients. One of such methods is laser irradiation of the injection sites, which, among other things, makes it possible to reduce vaccine amount.
The purpose of this review is to analyze publications on the use of laser to stimulate the immune response. Four different classes of lasers are known to systemically enhance the immune response to intradermal vaccination: pulsed lasers, continuous mode lasers, non-ablative fractional lasers, and ablative fractional lasers. Each laser vaccine adjuvant is characterized by radiation parameters, modes of action, and immunological adjuvant effects that differ significantly. The authors consider main classes of lasers used as immunological adjuvants. The specificity of each laser will help to choose the most effective option to achieve the clinical goal when using a particular vaccine.
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Siders, Galvin, Erlandson, Bayramian, Reagan, Sistrunk, Spinka, and Haefner. "Wavelength Scaling of Laser Wakefield Acceleration for the EuPRAXIA Design Point." Instruments 3, no. 3 (August 21, 2019): 44. http://dx.doi.org/10.3390/instruments3030044.
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Scaling the particle beam luminosity from laser wakefield accelerators to meet the needs of the physics community requires a significant, thousand-fold increase in the average power of the driving lasers. Multipulse extraction is a promising technique capable of scaling high peak power lasers by that thousand-fold increase in average power. However, several of the best candidate materials for use in multipulse extraction amplifiers lase at wavelengths far from the 0.8–1.0 μm region which currently dominates laser wakefield research. In particular, we have identified Tm:YLF, which lases near 1.9 µm, as the most promising candidate for high average power multipulse extraction amplifiers. Current schemes to scale the laser, plasma, and electron beam parameters to alternative wavelengths are unnecessarily restrictive in that they stress laser performance gains to keep plasma conditions constant. In this paper, we present a new and more general scheme for wavelength scaling a laser wakefield acceleration (LWFA) design point that provides greater flexibility in trading laser, plasma, and electron beam parameters within a particular design point. Finally, a multipulse extraction 1.9 µm Tm:YLF laser design meeting the EuPRAXIA project’s laser goals is discussed.
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Juhász, Gergely, Miklós Berczeli, and Zoltán Weltsch. "Formation of Oxide Layers with Femtosecond Laser on Steel Surfaces for Color Marking." International Journal of Engineering and Management Sciences 5, no. 2 (April 15, 2020): 174–78. http://dx.doi.org/10.21791/ijems.2020.2.22.
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With the appearance of ultrashort pulse lasers, the researchers have begun working on various laser marking technology. Atmospheric heating and ablation of a surface induce laser coloration of metal surfaces. However, their application is still problematic today in the industry. With the appearance of femtosecond pulse lasers, a new concept became available for color marking. This concept is based on the formation of laser-induced periodic surface structures (LIPSS) on metal surfaces. The purpose of this article is to summarize the literature of laser color marking with ultrashort pulse lasers.
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Wertlen, L. "Lasers in Medicine." Acupuncture in Medicine 10, no. 1 (May 1992): 23–24. http://dx.doi.org/10.1136/aim.10.1.23.
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Lasers now have a wide variety of medical applications, ranging from the dissolution of coronary artery thrombus to the repair of a detatched retina. The main types of laser in medicine are surgical, photocoagulator, photoradiation therapy, and cold lasers which are used by acupuncturists. Cold lasers act directly on cells to improve healing and reduce inflammation. They are also used as an effective substitute for needling or electrical stimulation.
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Cerrato, Clara, Victoria Jahrreiss, Carlotta Nedbal, Amelia Pietropaolo, and Bhaskar Somani. "Evolving Role of Lasers in Endourology: Past, Present and Future of Lasers." Photonics 10, no. 6 (May 31, 2023): 635. http://dx.doi.org/10.3390/photonics10060635.
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The use of lasers in endourology has grown exponentially, leading to technological advancement and to miniaturization of the procedures. We aim to provide an overview of the lasers used in endourology and the associated future perspectives. Using MEDLINE, a non-systematic review was performed including articles between 2006 and 2023. English language original articles, reviews and editorials were selected based on their clinical relevance. Guidelines recommend ureteroscopy in case of stones <2 cm and a percutaneous approach for renal stones ≥2 cm. High-power holmium (Ho:YAG) lasers and the new thulium fibre laser (TFL) may change the future, offering shorter procedures for complex stones, with good outcomes. Increased intrarenal temperature associated with these new technologies may be overcome with adaptive strategies and optimal settings. For upper-tract urothelial carcinoma (UTUC), the combination of laser techniques and these new lasers may reduce the risk of stenosis and allow for a more accurate tumour ablation, potentially reducing the recurrence rates. Laser enucleation procedures are gaining a major role in benign prostate enlargement (BPE), especially in patients with larger prostates or under anticoagulant therapy. However, the superiority of one laser over the other has not been established yet, and the choice of technique is mainly deferred to the surgeon’s expertise. In conclusion, lasers will further expand their horizon in endourology, allowing for instrument adaptation to challenging anatomy. Prospective, randomized clinical trials are however needed to confirm available results and to provide the optimal settings for each pathology.
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Malcangi, Giuseppina, Assunta Patano, Irma Trilli, Fabio Piras, Anna Maria Ciocia, Alessio Danilo Inchingolo, Antonio Mancini, et al. "Therapeutic and Adverse Effects of Lasers in Dentistry: A Systematic Review." Photonics 10, no. 6 (June 5, 2023): 650. http://dx.doi.org/10.3390/photonics10060650.
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Laser therapy has become one of the gold standards of treatment in routine dentistry. In the 1970s, CO2 lasers were the first lasers to be used in oral surgery on soft tissues. Subsequently, other lasers (Diode, Nd YAG, Er: YAG, Argon and Erbium) have also been used in periodontics, implantology, orthodontics and restorative dentistry, as well as for hard tissues, such as bone, enamel and dentin. The purpose of this systematic review is to analyze both the therapeutic properties and adverse effects of laser use in dentistry, related to a non-targeted choice of medical device based on clinical need as well as an inadequate learning curve. A systematic review was performed following the PRISMA guidelines using Pubmed, Scopus and Web of Science. The use of lasers requires a specific learning curve modifying the standard surgical approach. The use of lasers provides multiple therapeutic benefits but can lead to some failures in dental treatments. In restorative dentistry, it has been found that lasers can cause cracks that can lead to fractures and/or affect the composite restoration. In periodontal treatments, the use of lasers can produce thermal damage to pulp tissue. In surgical treatments, the use of a laser caused bleeding, post-operative pain and a burning sensation. The failure of tissue cooling during laser beam emission could produce the necrosis of hard and soft tissues.