共查询到18条相似文献,搜索用时 125 毫秒
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为了提高飞秒激光加工的效率和灵活性,设计了一套飞秒激光全息并行加工系统,并对该系统中加载计算全息图(CGH)生成的多焦点均一性和空间位置分布的关系进行了研究.首先,将空间光调制器(SLM)引入飞秒激光加工光路;然后,采用GS(Gerchberg-Saxton)算法设计了直线型和三角型分布的三焦点阵列.最后,通过数值仿真和实验研究比较了用两种不同空间分布的焦点列阵设计的全息图对均一性的影响.结果表明,在焦点阵列间距较小的情况下,直线型分布设计的焦点阵列不易获得好的均一性,三焦点U仅有79%;而用三角型分布焦点阵列设计时,可以获得很好的均一性,三焦点U约等于100%.实验数据表明,三角形分布的三焦点可以实现高质量的并行加工,加工的半球状微结构阵列具有微透镜阵列的功能. 相似文献
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将飞秒激光双光子聚合加工技术和毛细力诱导自组装技术相结合实现了各向异性结构和多级结构的制备。首先,使用飞秒激光双光子加工技术加工出微柱阵列,将微柱置于显影液中显影,然后放置在空气中。在显影液蒸发的过程中,微柱结构单元受到毛细力的作用而弯曲实现自组装。通过控制微柱的高度和直径的不一致性实现了两种各向异性结构制备方法,并成功制备了底层微柱直径分别为2μm和6μm双层结构。由于毛细力的大小和微柱高度无关,且同样端部变形量下较高微柱的弹性回复力小于较低微柱的弹性回复力,更易发生弯曲;直径较大的微柱具有更强的抗弯曲能力,从而引导直径较小的微柱向较大的微柱倾斜,藉此制备了各向异性结构。使用毛细力自组装辅助飞秒激光微纳加工可以实现灵活可控的复杂3D结构的加工,并将在生物医药、化学分析、微流体等领域发挥重要作用。 相似文献
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以激光精密加工金属血管心脏支架生产工艺为基础,探索了可降解心脏支架的飞秒激光精密加工方式。利用飞秒激光的超短脉冲和超高峰值功率的特性,实现了以聚乳酸(PLA)为材料的可降解心脏支架的激光精密加工。设计了椅形衬套,稳定了激光焦斑位置,分析得出了最佳衬套离焦距用于配合飞秒激光精密加工。通过调试工艺参量,解决了由于材料本身特性引起的切缝边缘易炭化和加工过程中由于离焦量和焦斑位置准确度不稳定导致不能精密加工的问题,实现了对非金属可降解心脏支架的无热精密加工。说明了飞秒激光配合椅形衬套加工非金属血管支架的可行性,确定了最佳加工参量,加工出了无热损伤切边光滑筋宽一致性为±6μm的可降解心脏支架样品。 相似文献
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针对传统加工方法很难实现微机电系统(Micro electromechanical systems,MEMS)零部件高质量加工的问题,在微细加工技术研究基础上,提出采用飞秒激光双光子聚合加工技术加工标准渐开线微齿轮的方法.采用钛蓝宝石激光器自行搭建的飞秒激光双光子加工系统,能够输出波长为800 nm的飞秒激光用于双光子聚合加工,利用AutoCAD软件设计标准渐开线微齿轮,通过理论和试验两种方法研究激光功率与单个固化点尺寸之间的关系,进而研究扫描步距与加工精度和表面粗糙度之间的关系,结果表明,激光功率越小,加工分辨率越高;扫描步距越小,加工变形越大,但表面质量提高.采用优化后的加工工艺参数加工出高质量的标准渐开线微齿轮,其表面粗糙度Ra27.66 nm.因此,飞秒激光双光子加工技术能够为微齿轮或其他MEMS零部件的加工提供一条有效途径. 相似文献
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Wenjun Wang Xuesong Mei Gedong Jiang 《The International Journal of Advanced Manufacturing Technology》2009,41(5-6):504-512
With increasing demand for microstructure shape accuracy for MEMS and optoelectronic devices, controllability of shape and morphology in micro-fabrication has become increasingly crucial. In this paper, the effects of processing parameters on the shape and morphology of microstructures in femtosecond laser fabrication of imprint roller are explored. An optimized fabrication process is proposed to acquire high accuracy microstructures, in which a two-step inclination ablation process and optimal laser focus position are adopted. Adjusting and matching the processing parameters is a basic method to acquire well-defined shapes, but the ablation results indicate that the draft angle of microstructures can only be adjusted in a limited range due to the intensity distribution of laser beam. A two-step inclination ablation process is adopted to increase the draft angle. In the two-step inclination ablation process, the laser beam irradiates the target surface with an angle and the microstructure with a much steeper draft angle forms after the two-step fabrication. Laser focus position is explored as an important parameter affecting the morphology, and an optimal laser focus position is obtained to enhance the ablation quality. By matching the laser fluence and laser focus position, this morphology enhancement method can realize the high-quality ablation of microstructures with a wide range of dimensions without changing the focusing objective lens. 相似文献
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We present a parallel depth resolved laser fabrication technique for micro- and nano-machining metal substrates based on temporal focusing. In this system, the spectrum of a femtosecond laser pulse is first spatially separated by a digital micromirror device, which simultaneously serves as a diffraction grating and a programmable binary mask. After collimation and beam flattening, an objective lens recombines the spectrum to the focal region, forming a high-intensity, depth resolved light sheet for laser micromachining. The light sheet technology enables parallel fabrication of highly uniform micro-structures of close to diffraction-limited resolution. Experimental results demonstrate high-resolution (~800 nm) direct area patterning on various metal substrates, e.g., nickel and copper, over an area of ~100 × 60 µm2 within tens of laser pulses. The relationship among material removal rate, surface flatness, laser power, and number of pulses have been experimentally studied; the results suggest the application of higher power with fewer number of laser pulses produce microstructures of better surface quality. The light sheet technology substantially improves the throughput of ultrafast laser machining, enabling direct area patterning without compromising the resolution. 相似文献
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Zhiwei Fang Ni Yao Min Wang Jintian Lin Jianhao Zhang Rongbo Wu 《International Journal of Optomechatronics》2017,11(1):47-54
We demonstrate fabrication of a high-quality factor lithium niobate double-disk whispering-gallery microcavity using femtosecond laser assisted ion beam milling. Using this method, two vertically stacked 30-µm diameter disks with a 200-nm gap are fabricated. With our device, an optical quality factor as high as 1.35?×?105 is demonstrated. Our approach is scalable to fabricate multiple disks on a single chip. 相似文献
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In this paper, an on-machine error calibration method, covering error modeling and measurement, is proposed to evaluate and compensate the errors caused by the mechanical and optical system equipped in the micromachining center using the femtosecond laser. Through preliminary tests by dicing silicon wafer, it has revealed that the squareness, laser beam misalign and focal position offset, are the main causes to result in the inaccuracy of micromachining. Consequently, an error modeling method is proposed to evaluate the error distribution in the workspace, and hereafter a comprehensive error vector of the laser beam, combining the squareness errors of Z-axis with the laser beam misalign, is generated by the variable substitution method. Subsequently, an increment error model in the instant local coordinates is established to satisfy the requirement of the programming method commonly used in the laser machine tools. Furthermore, a series of holes and grooves are machined on the femtosecond laser micromachining center to validate the proposed approach and model. The machining dimensions including diameters, distances and angles, are measured on-machine to identify the squareness errors, laser beam misalign and focal position offset according to the proposed error model. Finally, the experimental results show that, comparing to the uncompensated tests, the machining accuracy has been significantly improved with the proposed method. 相似文献
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Bin Xu Xiao-yu Wu Shi-quan Ling Feng Luo Chen-lin Du Xiu-quan Sun 《The International Journal of Advanced Manufacturing Technology》2013,66(5-8):601-609
This paper proposes a novel fabrication process based on femtosecond laser cutting and micro-electric resistance slip welding to address the bottleneck presented by ultraviolet–Lithographie, Galvanoformung, Abformung combined with micro-electroforming, in which micro-molds are usually fabricated with vertical wall structures. At first, 10-μm thick 0Cr18Ni9 stainless steel foils were cut by femtosecond laser to obtain several single-layer graphics which were then joined by micro-electric resistance slip welding. The slip welding process formed a 3D micro-structure and the weld zone of micro-structure was tested by the X-ray diffraction (XRD). The XRD results show that the phases of weld zone remain unchanged, but that the phase content slightly changes. Finally, a 3D metal micro-structure mold was processed under 110 mW femtosecond laser power, 0.1 mm/s cutting speed, 0.21 V welding voltage, 10 ms welding time, 0.2 MPa welding pressure, 0.5 mm bar electrode diameter, 160 time’s slip welding discharge, which proves that the forming process could be a useful method for the production of 3D micro-molds. 相似文献
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H.Y. Zheng H. Liu S. Wan G.C. Lim S. Nikumb Q. Chen 《The International Journal of Advanced Manufacturing Technology》2006,27(9-10):925-929
The capability of direct writing makes ultrashort pulse laser significant in the microfabrication of MEMS devices based on polymer and glass. In particular, nanosecond and femtosecond lasers are able to transfer the adequate energy in femtosecond intervals for the removal of the materials. Because of its advantages, just like the small feature size, smooth finishing surface, flexible structuring and the minimum thermal effect, ultrashort pulse lasers have become a convincing technique with the high peak power. This paper presents the femtosecond laser machining results of the polycarbonate, aluminosilicate glasses and nanosecond laser machining of aluminosilicate glasses. The microchannels with the critical micron-scale dimensions and the sub-micron scale surface roughness were achieved by the optimized operating parameters of the laser. The major influence factors such as cutting speed, power energy, and power stability were analyzed to obtain the optimized parameters for the fabrication of the microchannels for a bubble switch. The ultrashort pulse laser micromachining was applied in the prototype of a bubble optical switch. By miniaturization of the structure of the microchannel, the switch speed can be promisingly improved. 相似文献