OPT OpenIR研究单元&专题: 光子制造系统与应用研究中心
http://ir.opt.ac.cn:80/handle/181661/27502
2024-03-29T12:02:16Z
2024-03-29T12:02:16Z
飞秒激光多脉冲烧蚀过程中飞秒时间分辨电子状态的观测研究
王谦豪
赵华龙
杨小君
温文龙
李益
http://ir.opt.ac.cn:80/handle/181661/97070
2024-01-08T07:41:55Z
2024-01-08T07:39:02Z
题名: 飞秒激光多脉冲烧蚀过程中飞秒时间分辨电子状态的观测研究
作者: 王谦豪; 赵华龙; 杨小君; 温文龙; 李益
摘要: <p>为研究飞秒激光加工硬脆透明材料时存在的“微裂纹”与“诱导条纹”等共性工艺问题,利用飞秒时间分辨泵浦探测阴影成像技术,对飞秒激光多脉冲烧蚀石英玻璃过程中的电子动力学过程进行成像,分析了激光脉冲电离材料初期(700 fs之前)等离子体丝的演化情况。多脉冲诱导微结构的存在使成丝区域分布在微结构的两侧与光脉冲传播的轴线方向,前者主要是由微结构侧壁对光脉冲的折射造成的,而后者则是由微结构底面与侧壁形貌不同导致的光程差引起的。实验结果揭示了多脉冲加工过程中脉冲串诱导微结构对后续光场的重塑效应,该效应影响了等离子体成丝区域与能量沉积的分布,这是共性工艺问题产生的核心机制。</p>
2024-01-08T07:39:02Z
A compact 51.6-W, 26-μJ, Yb-doped all-fiber integrated CPA system through quasi-rectangular pulse pre-shaping
Li, Qianglong
Li, Feng
Liu, Hongjun
Zhao, Wei
Zhao, Hualong
Wang, Yishan
Wen, Wenlong
Cao, Xue
Si, Jinhai
http://ir.opt.ac.cn:80/handle/181661/96879
2024-01-03T07:00:50Z
2023-11-23T07:05:37Z
题名: A compact 51.6-W, 26-μJ, Yb-doped all-fiber integrated CPA system through quasi-rectangular pulse pre-shaping
作者: Li, Qianglong; Li, Feng; Liu, Hongjun; Zhao, Wei; Zhao, Hualong; Wang, Yishan; Wen, Wenlong; Cao, Xue; Si, Jinhai
摘要: <p>A compact 51.6-W, 26-μJ all-fiber integrated Yb-doped femtosecond laser source with pulse durations of 692 fs despite ∼18π nonlinear phase shift accumulation in the main amplifier is demonstrated by using fiber quasi-rectangular pulse pre-shaping. The numerical results are in good agreement with the experiment. Due to the advantages of an all-fiber spliced structure and a minimal pulse stretching ratio (from 26.3 ps to ∼70 ps), just a small size of gratings and a short separation distance between the two gratings in the compressor is required. Therefore, the laser source is exceedingly compact, robust, cost-effective, and easy to assemble. This technique is anticipated to accelerate the use of fiber femtosecond lasers in industrial applications. © 2023 Elsevier Ltd</p>
2023-11-23T07:05:37Z
Hybrid fiber-single crystal fiber chirped-pulse amplification system emitting more than 1.5 GW peak power with beam quality better than 1.3
Li, Feng
Zhao, Wei
Li, Qianglong
Zhao, Hualong
Wang, Yishan
Yang, Yang
Wen, Wenlong
Cao, Xue
http://ir.opt.ac.cn:80/handle/181661/96794
2024-02-22T02:38:45Z
2023-10-12T09:11:58Z
题名: Hybrid fiber-single crystal fiber chirped-pulse amplification system emitting more than 1.5 GW peak power with beam quality better than 1.3
作者: Li, Feng; Zhao, Wei; Li, Qianglong; Zhao, Hualong; Wang, Yishan; Yang, Yang; Wen, Wenlong; Cao, Xue
摘要: <p>A hybrid chirped pulse amplification system composed by the monolithic fiber pre-amplifier and a two-stage single-pass single crystal fiber amplifier was demonstrated. A maximum power of 68 W at the repetition rate of 100 kHz was obtained. The laser pulses were amplified and then compressed using a 1600 linemm grating pair compressor. A short pulse duration of 358 fs and a power of 54 W were obtained at 100 kHz, corresponding to a peak power of 1.508 GW, to the best of our knowledge, this is the highest peak power ever obtained from single crystal fiber at repetition rate above 100 kHz due to the consideration of the third order dispersion which was engraved in the stretcher and the tuning capacity of higher-order dispersion compensation of chirped fiber Bragg grating. Additionally, the beam quality better than 1.3 was obtained. This high peak power CPA system with excellent comprehensive parameters will find various applications in scientific research and industrial applications. Author</p>
2023-10-12T09:11:58Z
激光冷加工孔穿透光谱检测技术研究
闫庆
彭波
汪丽
王东
赵华龙
高飞
华灯鑫
http://ir.opt.ac.cn:80/handle/181661/96644
2023-08-01T08:48:05Z
2023-08-01T08:29:48Z
题名: 激光冷加工孔穿透光谱检测技术研究
作者: 闫庆; 彭波; 汪丽; 王东; 赵华龙; 高飞; 华灯鑫
摘要: <p>为了避免对存在空气内腔器件加工过程中对壁损伤问题,需要实时判断孔穿透状态。针对该问题提出基于激光诱导击穿光谱检测技术的飞秒激光制孔的孔穿透检测方法,选取Cr(I)521.531 nm为特征发射光谱,利用特征谱线强度的变化实现孔穿透状态的判断。设计了光谱检测实验系统并在孔加工实验过程中实现了特征光谱的采集与孔穿透状态的判断,验证了该方法在解决孔加工过程中避免产生对壁损伤问题的可行性。</p>
2023-08-01T08:29:48Z
Hundred watt level and high energy compact hybrid fiber femtosecond laser with good beam quality
Li, Qianglong
Li, Feng
Zhao, Wei
Wang, Yishan
Wen, Wenlong
Yang, Yang
Zhao, Hualong
Cao, Xue
Si, Jinhai
http://ir.opt.ac.cn:80/handle/181661/96449
2023-05-22T02:52:18Z
2023-05-19T03:06:57Z
题名: Hundred watt level and high energy compact hybrid fiber femtosecond laser with good beam quality
作者: Li, Qianglong; Li, Feng; Zhao, Wei; Wang, Yishan; Wen, Wenlong; Yang, Yang; Zhao, Hualong; Cao, Xue; Si, Jinhai
摘要: <p>A hundred watt level compact femtosecond laser system comprised of a high gain, low nonlinearity silicate glass fiber amplifier and a highly efficient Yb:YAG single-crystal fiber amplifier is demonstrated. By reducing the harmful thermal lens effect of amplifiers and optical elements, and precisely tuning dispersion of the stretcher, 110 W, 495 fs laser output at 1 MHz repetition rate and 250 mu J, 494 fs laser output at 200 kHz repetition rate are obtained. An optimized beam-quality factor (M (2)) of better than 1.3 is obtained by filtering the beam with a small-aperture diaphragm. To our best knowledge, this is the first demonstration of such a hybrid femtosecond laser over 100 W and 100 mu J with good beam quality.</p>
2023-05-19T03:06:57Z
高功率单晶光纤超短脉冲放大技术研究进展(特邀)
曹雪
李峰
赵华龙
王屹山
周伟
沈德元
http://ir.opt.ac.cn:80/handle/181661/96273
2023-01-17T01:36:17Z
2023-01-17T01:29:59Z
题名: 高功率单晶光纤超短脉冲放大技术研究进展(特邀)
作者: 曹雪; 李峰; 赵华龙; 王屹山; 周伟; 沈德元
摘要: <p>单晶光纤具有细长的晶体结构以及对泵浦光的波导传输特性,使其兼具晶体以及光纤的激光放大介质优点,其细长的晶体结构可以有效地进行散热,保证了在高功率运转下依然可以保证高光束质量,与传统的晶体棒相比,对泵浦光的波导特性使其具有更大的能量提取效率和放大增益,简单的行波放大结构使得系统易于集成。单晶光纤作为放大增益介质已广泛应用于高功率高能量超短脉冲激光放大技术中,并在科研、工业加工等领域具有重要的应用前景。本文重点介绍了单晶光纤的结构和制备方法,以及近年来1μm波段基于单晶光纤的超短脉冲放大技术研究的主要方法及结果,包括本课题组取得的主要进展,探讨和展望了单晶光纤放大技术的前景和发展方向。</p>
2023-01-17T01:29:59Z
轨迹可控的大深径比倒锥微孔加工系统及应用
王珊
赵卫
赵华龙
周峰
刘国强
杨小君
http://ir.opt.ac.cn:80/handle/181661/96171
2022-10-17T08:55:53Z
2022-10-17T08:51:39Z
题名: 轨迹可控的大深径比倒锥微孔加工系统及应用
作者: 王珊; 赵卫; 赵华龙; 周峰; 刘国强; 杨小君
摘要: <p>飞秒光纤激光器具有脉宽极短,瞬时功率高,对加工材料无选择性等特点,被广泛应用于精密微孔制造领域。为此,提出了一种高精度轨迹可调光束扫描系统,利用电机控制偏转光楔组和平行平板组相对于激光光轴的角度,再通过聚焦透镜缩小光斑,实现精准控制下飞秒激光的旋转扫描,解决了目前高深径比、倒锥孔加工困难的问题。将该系统应用于汽车喷油嘴油孔加工,实现了加工孔径的孔径为25~800μm,孔径误差≤±2μm;在锥度孔加工中可实现微孔锥度-5°~+5°;实现了深径比为20∶1的微孔加工。</p>
2022-10-17T08:51:39Z
Large dispersion-managed broadband high-energy fiber femtosecond laser system with sub 300 fs pulses and high beam quality output
Li, Feng
Zhao, Wei
Wang, Yishan
Li, Dongjuan
Song, Dongdong
Li, Qianglong
Yang, Yang
Wen, Wenlong
http://ir.opt.ac.cn:80/handle/181661/96159
2022-10-14T06:03:34Z
2022-10-14T03:24:08Z
题名: Large dispersion-managed broadband high-energy fiber femtosecond laser system with sub 300 fs pulses and high beam quality output
作者: Li, Feng; Zhao, Wei; Wang, Yishan; Li, Dongjuan; Song, Dongdong; Li, Qianglong; Yang, Yang; Wen, Wenlong
摘要: <p>We experimentally demonstrate a high-energy sub 300 fs polarization maintaining fiber chirped pulse amplifi-cation (CPA) system. The preamplifier is a monolithic fiberized system that uses two cascaded temperature -assisted dispersion-tuning broadband chirped fiber Bragg gratings (CFBGs) with a reflected bandwidth of 20 nm as stretchers. To make full use of the stretcher to lower the system's nonlinearity accumulation, a homemade mode locked fiber laser with a spectral width of 14.8 nm (full width at half maximum) is selected as the seeder to offer a stretched pulse width of 1.69 ns. The main amplifier is based on a one-stage simple Yb:YAG single crystal fiber amplifier with an amplified output power of 40.6 W at a repetition rate of 200 kHz, and the beam quality is conserved in a single mode beam profile with beam quality of 1.246 and 1.142 in the horizontal direction and vertical direction, respectively. During amplification, the spectral gain narrowing effect is observed. To achieve the high-speed switch of the laser, an acoustical optical modulator (AOM) is inserted before the compressor to achieve high-speed turn-on/off control. The compressor is based on a diffraction grating pair with a groove density of 1600 line/mm to offer a dispersion match with the stretcher of the CFBGs. With the CFBG's fine-tuned capacity of second-order dispersion and higher-order dispersion, the compressed average power of 29.6 W and pulse duration of 278 fs, corresponding to a pulse energy of 148 mu J and a peak power of 532 MW with ignoring the wings of the pulse, is obtained. The beam quality is well conserved after compression, and the beam quality is 1.250 and 1.196 in the horizontal direction and vertical direction, respectively. A power fluctuation of 0.1% (root mean square) and a beam pointing drift of 8.47 mu rad/C over 8 h are realized. This high peak power and high beam quality femtosecond laser is promising in science and industrial applications.</p>
2022-10-14T03:24:08Z
复杂曲面多特征点匹配的喷油嘴定位技术
梁晨涛
吴平
赵卫
赵华龙
奚秀锋
http://ir.opt.ac.cn:80/handle/181661/96010
2022-07-14T08:35:22Z
2022-07-14T08:30:50Z
题名: 复杂曲面多特征点匹配的喷油嘴定位技术
作者: 梁晨涛; 吴平; 赵卫; 赵华龙; 奚秀锋
摘要: <p><span style="background-color:#ffffff; color:#000000">汽车喷油嘴的喷油孔加工一般使用工装夹具进行定位并建立坐标系,工装夹具制造精度和安装误差会导致孔径、孔形以及孔的位置与理论值有较大的偏差,从而影响喷油嘴工作的可靠性,这对柴油机的整体性能、排放指标的稳定性甚至柴油机工作的可靠性产生严重影响。基于此,提出了一种基于多特征点匹配算法的高精度自适应定位技术。通过在真实的燃油喷嘴上测量若干(最少6个)特征点的空间位置,以模型中给出的特征点测量数据为基础,计算实际工件与理论模型在机床坐标系下的精确定位参数,以此计算工件上所有待加工孔的机床参数。实验结果表明,工件定位精度小于等于0.1 mm。该定位技术能有效减小孔加工偏差,是解决燃油喷嘴定位精度的一种有效可行的方案。</span></p>
2022-07-14T08:30:50Z
Large Dispersion-Managed Broadband High-Energy Fiber Femtosecond Laser System with Sub 300 Fs Pulses and High Beam Quality Output
Li, Feng
Zhao, Wei
Wang, Yishan
Li, Dongjuan
Li, Qianglong
Yang, Yang
Wen, Wenlong
Song, Dongdong
http://ir.opt.ac.cn:80/handle/181661/95867
2022-05-16T09:36:08Z
2022-05-16T08:44:04Z
题名: Large Dispersion-Managed Broadband High-Energy Fiber Femtosecond Laser System with Sub 300 Fs Pulses and High Beam Quality Output
作者: Li, Feng; Zhao, Wei; Wang, Yishan; Li, Dongjuan; Li, Qianglong; Yang, Yang; Wen, Wenlong; Song, Dongdong
摘要: We experimentally demonstrate a high-energy sub 300 fs polarization maintaining fiber chirped pulse amplification (CPA) system. The preamplifier is a monolithic fiberized system that uses two cascaded temperature-assisted dispersion-tuning broadband chirped fiber Bragg gratings (CFBGs) with a reflected bandwidth of 20 nm as stretchers. To make full use of the stretcher to lower the system’s nonlinearity accumulation, a homemade mode locked fiber laser with a spectral width of 14.8 nm (full width at half maximum) is selected as the seeder to offer a stretched pulse width of 1.69 ns. The main amplifier is based on a one-stage simple Yb:YAG single crystal fiber amplifier with an amplified output power of 40.6 W at a repetition rate of 200 kHz, and the beam quality is conserved in a single mode beam profile with beam quality of 1.246 and 1.142 in the horizontal direction and vertical direction, respectively. During amplification, the spectral gain narrowing effect is observed. To achieve the high-speed switch of the laser, an acoustical optical modulator (AOM) is inserted before the compressor to achieve high-speed turn-on/off control. The compressor is based on a diffraction grating pair with a groove density of 1600 line/mm to offer a dispersion match with the stretcher of the CFBGs. With the CFBG’s fine-tuned capacity of second-order dispersion and higher-order dispersion, the compressed average power of 29.6 W and pulse duration of 278 fs, corresponding to a pulse energy of 148 µJ and a peak power of 532 MW, is obtained. The beam quality is well conserved after compression, and the beam quality is 1.250 and 1.196 in the horizontal direction and vertical direction, respectively. A power fluctuation of 0.1% (root mean square) and a beam pointing drift of 8.47 µrad/°C over 8 hours are realized. This high peak power and high beam quality femtosecond laser is promising in science and industrial applications. © 2022, The Authors. All rights reserved.
2022-05-16T08:44:04Z