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从光学偏转超微力检测原理出发,严格地分析了在激光光源具有一定空间光强分布的情况下其检测的结果。我们发现激光源的空间光强分布在超微力检测条件下对检测结果没有影响,即其PSD的输出信号完全正确地反应了悬臂梁的受力大小。但是,PSD所检测光斑的重心位置对应的光线将随悬臂梁受力大小的不同而不同。本文给出了入射光经弯曲悬臂梁反射后空间光强分布变化的计算方法和计算实例,并提出了进一步从反射光束中提取上述变化信息并加以应用的建议 相似文献
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随着半导体激光自身输出功率和转换效率的提升,半导体激光已经广泛的应用于激光加工领域。本文针对目前激光加工领域对半导体激光硬化光源的需求,研制了波长为976nm的连续输出半导体激光硬化光源。该光源采用空间/偏振合束工艺达到了较高的合束效率,采用柱面微透镜阵列分割与聚焦镜复合较好地匀化了巴条激光器慢轴方向固有的光强起伏,使聚焦光斑的光强呈平顶分布。最后对该光源进行了实验装调和测试。结果表明,在工作电流为93A时,光源的最大输出功率为5 120W,电光转换效率达47%,光斑尺寸为2mm×16mm,光斑分布为平顶分布,平整度大于90%,满足工业中对大面积、高效率激光硬化的要求。 相似文献
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针对传统光轴角测量系统中人为因素干扰导致的重复性能降低等不足,设计一种基于图像处理技术与高精度电控转台相结合的自动测量方案。分析了照明光斑光强分布特性,提出了一种基于图像区域分割的最优非线性加权的特征点提取算法。该方法根据光强与灰度的线性关系,将光强量化到3个区间。然后分析灰度因素在特征点定位中的影响;针对不同区间应用局部最优加权法则以实现局部最优化处理。最后,利用光轴偏转角与特征点在像面上位移的对应关系,计算得到光轴角测量值。开展了光斑特征点重复性实验并分析了光轴角检测精度,结果表明:该系统在不同光强、不同角度条件下重复性好,测角精度优于60.18″。与激光光源的光轴角测量实验对比,该算法在光斑光强分布不均的条件下仍能完成稳定且精确的光轴角测量。 相似文献
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在偏心摄影验光法中,采用垂轴线光源并以近视眼为例,分析了眼瞳图像中垂轴子午线上的光强分布,利用任意两端点的光强比值,导出了人眼屈光度的计算式.该方法简单易行,能较好解决测量中的盲区问题. 相似文献
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影像测量中的光源自适应控制系统研究 总被引:2,自引:0,他引:2
分析了影像测量中现有的手动光源调节系统的缺点,介绍了一种光源自适应控制系统的应用原理,给出了其硬件电路和软件算法设计,并通过构建的光学系统成像模型得出了CCD器件的电荷量与光源的光强、入射角、光源到测量对象的距离关系,提出了用阈值范围内平均梯度值来评价最佳光强的新方法,实现了PID控制对光强的调节,最后对光源自适应控制系统进行了自适应控制和抗外界干扰实验.实验结果表明此控制系统具有较好的稳定性和控制精度,在此系统的调节下,影像测量在不同外界光源条件下,0.7 s内能拍摄出清晰的图像. 相似文献
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王新华 《试验技术与试验机》2004,44(1):20-21,24
本文介绍了光学测量技术在逆向工程中的应用,分析了不同光源在物体扫描时的作用,介绍了一种光强可调的白炽光源与LED光源,通过采用三端可调集成稳压器可将电压在较大范围内进行调节,并对各性能参数进行了分析与说明。 相似文献
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本文介绍了光学测量技术在逆向工程中的应用,分析了不同光源在物体扫描时的作用,介绍了一种光强可调的白炽光源与LED光源,通过采用三端可调集成稳压器可将电压在较大范围内进行调节,并对各性能参数进行了分析与说明. 相似文献
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Reconfigurations of manufacturing systems—an empirical study on concepts, research, and applications
Ateekh-Ur-Rehman A. Subash Babu 《The International Journal of Advanced Manufacturing Technology》2013,66(1-4):107-124
It is well known that the performance of a manufacturing system is susceptible to sudden changes in demand, either in terms of the quantity of products concerned or the product mix. Traditional manufacturing managers have been dealing with such situations by resorting to outsourcing of products; employing additional resources in terms of overtime, extra shifts, etc.; and adopting back logging policies using the goodwill of customers or making use of effective scheduling and inventory policies. However, in the recent times, they are also presented with the option of reconfiguring the manufacturing system (RMS), which offers a number of benefits. There are several keys enabling technologies to realize these benefits. The review of related literature helped in realizing that there are a number of alternative ways of resorting to reconfiguration. In this paper, the views and experiences of various researchers and practitioners as reported in literature are presented in an encapsulated manner bringing forth the multidimensional aspects of the subject area RMS. From various accounts reported in the international and Indian media, it is evident that the Indian manufacturing sector is performing well and is trying out various innovative practices; interestingly, many of which are related to RMS. A survey of Indian industries was carried out with the help of a survey using questionnaire as an instrument. The survey revealed various interesting facts about various RMS practices followed by the Indian manufacturing sector and the impact of reconfiguration on various performance measures of these organizations. The details of the survey and the findings of the same are also presented in this paper. 相似文献
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The dynamics of prestressed orthogonal coarse nets are investigated using a finite element analysis; the effects of various cross weave reinforcements are considered. Element overstress, arrest times and net penetration are numerically predicted for various impact velocities and the data is collapsed to yield two empirical fits of use in net design. 相似文献
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将分形几何与电化学原理相结合,以Microsoft Visual C++6.0为平台,编程模拟了电解质浓度对点电极电沉积和喷射电沉积中枝晶分形生长的影响。采用圆形电解池点电极电沉积的方法,制备了不同浓度下的金属镍枝晶;以平行板金属镍为阳极,石墨板为阴极,用自行设计的试验设备研究了不同浓度时金属镍枝晶二维电沉积生长的行为特性,并分别与模拟结果进行比较。结果表明,电解质浓度变化对电沉积的影响与采用模型模拟所得的结果具有相似性,模拟的结果对电沉积枝晶的试验研究具有很好的指导意义,气泡对沉积产物的形貌影响显著。 相似文献
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H. P. Feuerbaum 《Scanning》1983,5(1):14-24
There are eight e-beam methods of testing integrated circuits. The principle and performance of the various methods will be discussed in this paper. The performance criteria are voltage resolution and the frequency range in which voltage changes can be detected. From this it is possible to decide which methods are best suited for testing the various IC types available today. 相似文献
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The friction and wear properties of nylon 总被引:13,自引:0,他引:13
The effects of temperature on the friction of nylon are examined at various sliding velocities. Maximum friction values are obtained, but it is found that when specimens slide continuously at various velocities, the magnitude of the maximum friction varies with the velocity, while when specimens slide alternately at 10 and 0.1 mm s−1, nearly the same maximum value is obtained. In the latter case, the displacement of the friction-velocity curves at various temperatures along the velocity axis can give a master curve while in the former case this is impossible.
The effects of temperature, velocity and load on the wear of nylon are also examined. Minimum values of the wear are obtained in all cases, whereas maximum values of the friction are obtained. The mechanism of such behaviour is discussed. 相似文献