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Record 421 of
Title:Optical design of monocentric multiscale three-line array airborne mapping camera
Author(s):Yan, Aqi(1); Dong, Sen(1); Wu, Dengshan(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12166 Issue: DOI: 10.1117/12.2613976 Published: 2022
Abstract:In view of the urgent demand high resolution and large field of view on three-line array airborne mapping camera, the paper proposes a new idea which applies monocentric multiscale principle to three-line array airborne mapping camera with high resolution and large field of view (FOV), and gives the design method and design process of optical system. monocentric multiscale optical system is designed, focal length is 70mm, resolution is 0.1m@2Km, and there are four multispectral bands which are panchromaticRGB band. The Base to Height ratio (B/H) is 0.83. The FOV of monocentric multiscale optical system is 80°, and working FOV is 60° which can be extended to 105°. The optical system has excellent imaging quality and successfully solved contradiction between large FOV and high resolution. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
Accession Number: 20220911734820
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Record 422 of
Title:Research Progress in Chalcogenide Glass Fibers for Infrared Laser Delivery
Author(s):Zhang, Hao(1,2); Guo, Haitao(1); Xu, Yantao(1,2); Li, Man(3); Ma, Wenchao(3)
Source: Zhongguo Jiguang/Chinese Journal of Lasers Volume: 49 Issue: 1 DOI: 10.3788/CJL202249.0101007 Published: January 10, 2022
Abstract:Significance: As the performance of mid-infrared lasers continues to improve, there occurs an increasing demand for their applications in laser surgery, military, materials processing, and other fields. Compared with spatial optical systems, the use of infrared fibers for laser transmission can greatly reduce the size of an optical system and improve the compactness and reliability of the whole system. For example, in the medical field, a considerable amount of laser surgery is performed using 2.94 μm Er: YAG lasers. The Er: YAG laser radiation absorption is very strong because this laser wavelength is practically in the center of the maximum absorption band of cellular water. Since biological tissues contain up to 70%~90% water, the Er: YAG laser is extremely efficient for their high precision cutting and vaporization. In addition, in the military field, another important application for 2 μm to 5 μm short-wave mid-infrared lasers is infrared countermeasures (IRCM) or laser tactical systems. Transmitting high power infrared lasers by infrared fibers can deflect or dazzle the infrared target seeking system. This application puts a high demand on the power handling capability of the fiber (typically tens of watts). For 512 μm long-wave mid-infrared lasers, high power CO (5.4 μm) and CO2 (10.6 μm) lasers can be used for laser surgery, industrial cutting, and welding applications. In addition, the transmission of laser power through optical fibers enables remote operation. Due to the characteristics of wide infrared transmission, good physical and chemical stabilities, and easily fiberized performances, chalcogenide glass is one of the best materials for infrared laser power delivery fiber. Therefore, as an important infrared fiber, the fabrication and application of chalcogenide glass fiber have been paid much attention at home and abroad. This review introduces the research progresses of domestic and foreign research groups in the preparation and application of chalcogenide fibers (including the step-index fibers and micro-structured fibers) for infrared laser power delivery. Progress: Step-index chalcogenide glass fibers are the earliest and most mature chalcogenide fibers. For 25 μm short-wave mid-infrared lasers, researchers first studied chalcogenide multi-mode fibers. In 1998, the US Naval Laboratory reported the successful transmission of a 2.94 μm wavelength medical free electron laser (MFEL) using an As40S60 multi-mode fiber. This result showed that laser surgery should be possible using a chalcogenide multi-mode fiber. Both CW and pulsed laser transmissions through chalcogenide multi-mode fibers were then subsequently reported. With the continuous development of mid-infrared lasers, while large-core multi-mode fibers can transmit higher power lasers, laser transmission quality and transmission modes still had to be considered, which require the development of small-core single-mode fibers. In 2018, the University of Central Florida examined the potential of chalcogenide fibers to handle high power mid-infrared lasers. The AR-coated As40S60 single-mode fiber enables the delivery of 10.3 W laser at 2.053 μm (Fig. 1). For 512 μm long-wave mid-infrared lasers, a multi-hundred-watt CO laser has been successfully delivered through chalcogenide glass fibers under gas cooling conditions (Fig. 2). And Te-based chalcogenide fibers can deliver a CO2 laser with tens of watts. The laser transmission of different chalcogenide step-index fibers has been summarized (Tabled 1). It can be seen that chalcogenide step-index fibers have made a great progress in mid-infrared laser transmission. At present, a multi-mode step-index fiber can achieve multi-hundred-watt laser transmission, while a single-mode step-index fiber can basically meet the demand for laser transmission within 10 W, and has been experimentally demonstrated in the fields of laser surgery and laser processing. Although a great progress has been made in chalcogenide step-index fibers, traditional step-index fibers are incapable due to material limitations with the increase in transmission power. In order to achieve a high power laser delivery, increasing the mode field area is the most direct and effective solution, and at the same time to ensure the beam quality, the transmission in fibers is required to be single-mode. A hollow-core micro-structured optical fiber (HC-MOF) and a large-mode-area photonic crystal fiber (LMA PCF) have become effective approaches to enhance the capability of power handling of chalcogenide fibers. Hollow-core micro-structured fibers can be divided into hollow-core Bragg fibers, hollow-core photonic crystal fibers (HC-PCFs) and hollow-core anti-resonant fibers (HC-ARFs). As researchers continue to study the numerical simulation and fabrication of micro-structured optical fibers, HC-ARFs have become the most promising infrared fibers for a high power laser delivery. The development of HC-ARFs is an encouraging advance in the fiber technology which combines the low theoretical loss over a wide bandwidth with a high tolerance to fabrication imperfections. A tolerance to fabrication imperfection is particularly important for chalcogenide fibers. At present, the minimum loss of HC-ARFs is 2.1 dB/m at 10 μm. This result indicates that HC-ARFs have already some practical value. Conclusions and Prospects: Chalcogenide fibers have been used in laser processing, laser surgery, and homeland security. The development of chalcogenide fibers with low loss and high laser damage threshold has great scientific value and application prospects. In particular, hollow-core micro-structured fibers are a technological race for the next generation of infrared fibers and related applications. ? 2022, Chinese Lasers Press. All right reserved.
Accession Number: 20221211825987
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Record 423 of
Title:Highly linear integrated lithium niobate modulator based on ring-assisted Mach-Zehnder interferometer
Author(s):Feng, Hanke(1); Zhang, Ke(1); Sun, Wenzhao(1); Ren, Yangming(2,3); Zhang, Yiwen(1); Zhang, Wenfu(2,3); Wang, Cheng(1)
Source: Optics InfoBase Conference Papers Volume: Issue: DOI: Published: 2022
Abstract:We report an ultra-high-linearity modulator on thin-film lithium niobate platform based on the ring-assisted Mach-Zehnder interferometer (RAMZI) structure, with measured spurious free dynamic range (SFDR) up to 120.04 dB·Hz4/5 at 1GHz. ? Optica Publishing Group 2022, ? 2022 The Author(s)
Accession Number: 20223512662422
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Record 424 of
Title:Fastening torque simulation method of pressure-ring based on finite element simulation analysis and experimental verification
Author(s):Zhao, Yue(1); Kang, Shifa(1); Fu, Xihong(1); Zhang, Gaopeng(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12166 Issue: DOI: 10.1117/12.2611752 Published: 2022
Abstract:Aiming at the problem of abnormal sound of lens caused by incomplete tightening of pressure coil after optical lens installation, this paper presents a method for calculating and verifying the tightening moment of pressure coil. According to the mechanical dimension of the screw thread of the pressing ring, the mechanical properties of the pressing ring of the mirror tube and the optimal number of turning rings were calculated and analyzed. In order to meet the practical application requirements, the tightening moment of the pressure coil obtained by the solution was brought into the 3D model for simulation, and the finite element modeling analysis of the tightening moment of the pressure coil of the optical lens was completed, so as to further solve the displacement variation of the lens group. Finally, the above analysis results were quantified by torque wrenches, and random vibration was carried out at one third of the order of acceptance level vibration test conditions, so as to complete the bottom analysis and verify the tightening torque of the screw ring under different ratios of XM-31 adhesive and vulcanizing agent. The experimental results show that the characteristic sweep curve of the optical lens does not change before and after the vibration, the mode of the optical lens remains stable all the time, and the data modal analysis results are consistent with the actual situation. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
Accession Number: 20220911734801
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Record 425 of
Title:Research on the properties of Ta2O5optical films prepared with APS plasma assisted deposition
Author(s):Pan, Yong-Gang(1); Liu, Zheng(1); Liu, Wen-Cheng(1); Li, Mian(1); Zhang, Si-Bao(1); Luo, Chang-Xin(1); Zhang, Chun-Juan(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12166 Issue: DOI: 10.1117/12.2604831 Published: 2022
Abstract:Ta2O5 thin films are widely used in optical and microelectronic industry because of its superior optical and mechanical properties. In this paper, single-layer Ta2O5 thin films were prepared by APS plasma assisted electron beam evaporation deposition. Based on the theory of ion energy transfer, the selection criteria of APS process parameters were established. By optimizing APS source parameters, Ta2O5 thin films with different characteristics were prepared. The spectral and refractive index dispersion of Ta2O5 thin films were analyzed by Cary7000 spectrophotometer. The stress and surface roughness of Ta2O5 films were analyzed by Zygo interferometer. Experiment and analysis results showed that the characteristics of Ta2O5 thin films are closely related to APS plasma assisted processing parameters. The discharge current and bias voltage of APS source have great influence on the stress and surface roughness of Ta2O5 thin films, but have little influence on the spectral characteristics and refractive index dispersion. The influences of preparation parameters on the properties of Ta2O5 thin films were analyzed and optimization fabrication parameters were obtained. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
Accession Number: 20220911734999
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Record 426 of
Title:Spectroscopic properties of Er3+-doped fluoroindate glasses
Author(s):Liu, Zhen(1,2); She, Jiangbo(1,3); Peng, Bo(1)
Source: Journal of Rare Earths Volume: 40 Issue: 7 DOI: 10.1016/j.jre.2021.05.011 Published: July 2022
Abstract:The optical and thermal properties of a new class of fluoroindate glass with different erbium contents were investigated via Raman, transmission, and fluorescence spectroscopies, fluorescence decay curve analysis, and differential scanning calorimetry. The strength parameters of the samples were calculated using the Judd–Ofelt theory. The mid-infrared luminescence properties of erbium-doped fluoroindate glasses were studied, and a strong emission at 2.7 μm was obtained. Compared with the traditional ZBLAN glass, this glass has excellent emission properties, especially a longer fluorescence lifetime (7.09 ms) and larger emission cross-section (6.95 × 10?21 cm2) at 2.7 μm. The results indicate that fluoroindate glass is an attractive host for mid-infrared lasers and as a gain medium for optical amplifier applications. ? 2021
Accession Number: 20214010987220
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Record 427 of
Title:High Power Single Crystal Fiber Ultrashort Pulse Amplification Technology （Invited）
Author(s):Cao, Xue(1,2,3,4); Li, Feng(1); Zhao, Hualong(1); Wang, Yishan(1); Zhou, Wei(4); Shen, Deyuan(4)
Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 51 Issue: 8 DOI: 10.3788/gzxb20225108.0851513 Published: August 2022
Abstract:Femtosecond laser with high repetition rate and high output power can be used as the driving light source of attosecond pulse generation， which can effectively increase photon flux， obtain enough experimental data quickly， and overcome the existing problem of space charge effect. Therefore， it has important application value in high order harmonics and attosecond pulse generation. At the same time， high repetition rate and high output power femtosecond pulses also have important application prospects in ultrafast laser precision micro-machining field， which can solve the technical problems of hard， brittle and soft materials processing with high-precision and high-quality "cold machining" in aviation and aerospace field. With the rapid development of ultra-fast laser processing market， high power femtosecond laser system with higher cost performance has become the major factor of concern in the industry. Compared with traditional solid-state lasers， fiber amplifiers have many characteristics， such as easy operation， all-fiber fusion， easy integration， excellent heat dissipation performance， excellent beam quality， etc.， which have attracted much attention in the field of ultra-short pulse amplification. However， limited by the mode field area of ordinary single-mode or nearly single-mode fiber， the output energy of the ultrashort pulse based on the structure of optical fiber amplifier system is limited due to the Raman scattering and stimulated brillouin scattering， the self-phase modulation， cross phase modulation and other nonlinear effect in the process of high power pulse amplification. In order to achieve high energy femtosecond pulse amplification， the current fiber amplification system mainly adopts the structure of CPA system. Before amplification， the pulse is stretched in the time domain and the special fiber with large mode area is used to achieve high energy output in the space domain. Slab， disc and other solid amplifying media can output higher pulse energy，however，they are difficult to package， and the amplification structure is relatively complex， which is not conducive to the mass production of domestic lasers. Single crystal fiber as a new type of amplifier gain medium， it has a slender crystal structure and waveguide transmission characteristics for pump beam， which makes it have the advantages of both crystal and fiber laser amplification media. Its slender crystal structure can effectively dissipate heat， ensuring high beam quality under high-power operation. The waveguide characteristics of pump beam make it have greater energy extraction efficiency and higher amplification gain than traditional crystal rods. Compared with the fiber amplifier， the nonlinear accumulation of the single crystal fiber amplifier is much smaller， which is more conducive to the improvement of pulse energy. Meanwhile， the amplification structure of the single-crystal fiber amplifier mainly focuses on the single-pass or double-pass traveling wave amplification structure. Compared with the high complexity of the slab and thin-disk amplification system， the single-crystal fiber has better integration and stability. The waveguide structure of single-crystal fiber amplifier can match the multi-mode pump beam with the signal beam propagating in free space， which can obtain higher amplification efficiency and better beam quality than the traditional crystal rods. Excellent thermal management performance also enables the structure to achieve hundred-watt level ultra-short pulse output with good optical parameters. The hybrid fiber-single crystal fiber ultrashort pulse amplification system combined the high gain property of fiber laser and high peak power property of crystal gain medium. In order to further improve the average power and pulse energy， it has been less effective by simply stretching the pulse duration in time domain and increasing the optical fiber mode area in the space domain， technologies such as coherent beam combination can obtain much higher power and larger energy. When the output power of the laser is less than 200 W， the single crystal fiber can consitute a simple and reliable amplification setup. For higher power output， it can also be used as a stable， cost-effective seeder with good optical parameters for solid state amplifier， such as thin-disk lasers. In the future development of lasers， the research and development of fiber laser with appropriate wavelength for pump source and the continuous optimization of brightness of fiber coupled laser diode can effectively improve the amplification efficiency of ytterbium-doped single crystal fiber， and achieve a wider application in the field of ultrafast laser. The cladding structure of crystal fiber can increase the ratio of surface area to volume of single crystal fiber， by improving the heat transfer performance of cladding and the thermal management ability of fiber can realize the long distance fundamental mode waveguide， and finally realize the high power laser with higher efficiency， which is also an important direction of future development. Therefore， single crystal fiber as amplification gain medium has been widely used in ultrashort pulse amplification and has important application prospects in scientific research， national defense， industrial processing and other fields. This paper mainly introduces the structure and preparation methods of single crystal fiber， and the main research methods and results of ultrashort pulse amplification technology based on single crystal fiber in 1 μm waveband， including the main progress made by our research group， the prospect and development direction of single crystal fiber amplification technology are also discussed and prospected. ? 2022 Chinese Optical Society. All rights reserved.
Accession Number: 20223912795058
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Record 428 of
Title:Optical vortex array with deformable hybrid Ferris structures
Author(s):Long, Zixu(1,2); Zhang, Hao(1); Tai, Yuping(3); Tang, Miaomiao(1); Li, Hehe(1); Li, Xinzhong(1,2)
Source: Optics and Laser Technology Volume: 145 Issue: DOI: 10.1016/j.optlastec.2021.107524 Published: January 2022
Abstract:We proposed an optical vortex array (OVA) with deformable hybrid Ferris structures (DH-OVA). The DH-OVA was generated via the coaxial coherent superposition of two grafted elliptic perfect optical vortices (OVs) with different topological charges (TCs). The proposed DH-OVA exhibited the capacity of a free transformation from a circle to an ellipse except for the modulation of the number and sign of the unit OVs on the array. The OV distribution obeys the rule of uniform distribution of the area on the upper or lower half. By adjusting the initial phase difference, the orientation factor, and the direction of the grafted axis, a more complex OV motion and the entire hybrid rotation of the DH-OVA can be easily conducted according to the desired application. For instance, for the unidirectional and bidirectional motions of the OVs, regardless of whether they possessed the same or opposite signs, the entire rotation contained the unit OV's motion. During the OV's motion, the number of dark cores was not conserved, whereas the total TCs of the OVs were conserved on the DH-OVA. Results contrasted with the conventional wisdom on OVAs. Furthermore, the bidirectional motion of yeast particles via the DH-OVA was executed experimentally. This work provided a flexible DH-OVA, which will result in new potential applications in particle transfer, polarity particle sorting, and micro-particle manipulation. ? 2021 Elsevier Ltd
Accession Number: 20213810910150
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Record 429 of
Title:Fe3O4 nanoparticle-enabled Q-switched pulse generation in fiber laser
Author(s):Ban, Xiaoqiang(1,2); Sun, Penghuan(3); Qyyum, Abdul(3); Li, Xiaohui(3); Song, Zhuoying(3); Zhong, Ming(4); Little, Brent E.(1,2); Zhao, Wei(1,2)
Source: Optical Fiber Technology Volume: 71 Issue: DOI: 10.1016/j.yofte.2022.102909 Published: July 2022
Abstract:Fe3O4 nanoparticles (Fe3O4-NPs) are outstanding magnetic materials, which have plenty of applications in many fields, such as magnetic detection, ultrafast photonics, optical communication, etc. In this paper, we used co-precipitation method to synthesize Fe3O4-NPs, which formed saturable absorber (SA) in our erbium-doped fiber laser (EDFL). We obtained stable Q-switched pulses with central wavelength of 1530.46 nm and signal-to-noise ratio (SNR) of 54.4 dB when the pump power was 400 mW. When the pump power increased gradually, outline of the spectrum changed little, however, the repetition rate (RPR) increased gradually, meanwhile the pulse duration decreased gradually. In this experiment, when the pump power reached its maximum of 415.4 mW, the RPR reached its maximum of 72 kHz, meanwhile the pulse duration reached its minimum of 2.44 μs. It shows that Fe3O4-NPs-based passively Q-switched EDFLs have many potential applications, such as laser frequency doubling, laser radar, and study of interaction between light and matter, etc. ? 2022 Elsevier Inc.
Accession Number: 20221812056608
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Record 430 of
Title:All-optical Ti3C2Tx modulator based on a sandwich structure
Author(s):Li, Erkang(1); Jiang, Man(1); Li, Duidui(1); Wang, Ruiduo(2,3); Kang, Xin(1); Wang, Tianqi(1); Yan, Xiaoxin(1); Liu, Beibei(1); Ren, Zhaoyu(1)
Source: Applied Optics Volume: 61 Issue: 4 DOI: 10.1364/AO.445975 Published: February 1, 2022
Abstract:All-optical modulators based on MXene-Ti3C2Tx have recently garnered much attention due to their broadband light-matter interactions and its ultrafast carrier dynamics. To investigate the modulation characteristics of pump intensity and pump light modulation frequency, we establish an all-optical modulator with a sandwich structure based on MXene-Ti3C2Tx=PVA (polyvinyl alcohol) film. The result shows that this modulator can achieve a high modulation depth of 12.55 dB and a modulation frequency of 50 kHz corresponding to a response time at the microsecond scale. The successful preparation of the modulator is attributed to the saturable absorption characteristics of the MXene-Ti3C2Tx. This modulator has great potential in all-optical communications and ultrafast optical signal processing. ? 2022 Optica Publishing Group.
Accession Number: 20220511555197
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Record 431 of
Title:Theoretical and experimental study on Noise Equivalent Power of X-ray semiconductor ultra-fast response material based on the rad-optic effect
Author(s):Yan, Xin(1,2); Wang, Tao(2); Wang, Gang(2); Yao, Dong(1,2); Liu, Yiheng(2); Gao, Guilong(2); Xin, Liwei(1,2); Yin, Fei(2); Tian, Jinshou(2); Chang, Xinlong(1); He, Kai(2)
Source: arXiv Volume: Issue: DOI: 10.48550/arXiv.2206.10890 Published: June 22, 2022
Abstract:Semiconductor material based on the rad-optic effect enables ultra-fast detection of X-rays and plays an important role in fusion diagnostics. Obtaining the accurate noise equivalent power (NEP) of the semiconductor ultrafast response material is the key to detecting X-rays. In this paper, the refractive index change mechanism of the semiconductor under X-ray irradiation was analyzed, and the quantitative relationship between the diffraction efficiency and the X-ray photon energy was established through the LT-AlGaAs diffraction imaging experiments. The impulse responses of LT-AlGaAs under 1 KeV-10 KeV X-ray radiation were calculated, revealing the variation of NEP density with radiated photon energy. In the case of bombarding the Al target to generate 1.5 KeV X-rays, the imaging experiments of LT-AlGaAs were performed. The diffraction image of LT-AlGaAs has a linear relationship with the radiation intensity, and the NEP density of LT-AlGaAs reaches 4.80×105W/cm2. This study has reference significance for the development of ultra-fast X-ray imaging systems based on the rad-optic effect. ? 2022, CC BY.
Accession Number: 20220214035
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Record 432 of
Title:Analysis and Design of Fault Prediction and Health Assessment System for the optoelectronic Equipment
Author(s):Zhang, Chuming(1); Wei, Guojun(1); Wang, Xuan(2); Cao, Yu(2); Xie, Meilin(2)
Source: IMCEC 2022 - IEEE 5th Advanced Information Management, Communicates, Electronic and Automation Control Conference Volume: Issue: DOI: 10.1109/IMCEC55388.2022.10019826 Published: 2022
Abstract:In recent years, due to the rise of emerging technologies such as integrated circuits, artificial intelligence and big data, Optical measurement equipment performance is also constantly improving, more and more new technology, new processes, new materials continue to appear. Therefore, the maintenance of the optoelectronic equipment is also much more difficult. Based on these problems, this paper investigates the application of fault prediction and health management in optoelectronic devices. The main analysis and design of the system failure prediction and health assessment, and in response to the needs of optoelectronic devices for the life analysis, health status determination, fault prediction alarms, etc, designed a failure prediction and health assessment system for optoelectronic devices. ? 2022 IEEE.
Accession Number: 20230713575048
