非相干LED光源产生高阶Bessel光束  

High order Bessel beams generated by using incoherent LED light source

作　　者：何西[1] 吴逢铁[1] 李攀[1] 陈姿言 

机构地区：[1]华侨大学信息科学与工程学院,厦门361021

出　　处：《中国科学：物理学、力学、天文学》2014年第7期705-711,共7页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(批准号:61178015);福建省自然科学基金(编号:2012J01278)资助项目

摘　　要：首次采用单色LED绿光光源得到较理想的高阶Bessel光束,提出由交叉谱密度和多波长叠加理论计算出绿光LED发出的光经过螺旋相位板和轴棱锥后的光强分布,模拟出沿轴向不同距离处的截面光强分布图,设计一套实验装置进行实验验证,结果表明:通过光阑提高光场的空间相干性可以用绿光LED得到近似高阶Bessel光束,所得光束的截面光强分布,中心暗斑大小及最大无衍射距离均与理论计算相符.研究结果对非相干光实现粒子微操作提供理论和实验依据.The ideal high order Bessel beams was generated by monochromatic green LED light source for the first time. A novel method using cross-spectral density function and superposition of multi-wavelength was proposed to calculate the intensity distribution of light field emitted from the green LED then through the spiral phase plate and the axicon. And the cross-section intensity distribution along the optical axis based on this method was simulated. An experimental facility was designed to demonstrate the theory. The result showed that the high order Bessel beams could be obtained from the green LED light source by using the aperture to improve the spatial coherence of the light field emitted from the green LED. The cross-section intensity distribution of the experimental result, the size of the center dark spot and the non-diffraction distance were accorded well with the theoretical simulation and calculation. The research result offered the theoretical and experimental basis for the micromanipulation of particles by using incoherent light.

关 键 词：高阶Bessel光束 LED光源 交叉谱密度 螺旋相位板 轴棱锥 

分 类 号：TN312.8[电子电信—物理电子学]