【摘要】 设计了一种基于贝塞尔光束衍射的自由空间涡旋光发生器。贝塞尔光束在单模通过一个螺旋相位盘在光纤末端传输的方法,然后逐渐演变为涡旋光束,并可在采用自由空间中进行调制。利用时域有限差分(FDTD)软件对发生器的工作波长范围、极化灵敏度和加工容差等特性进行了分析。对比不同拓扑数值的涡旋光束在自由空间中传播100μm的结果,表明本文提出的光纤涡旋光发生器具有在光纤中自然获得的贝塞尔光束的非衍射特性,能够产生特定的贝塞尔光束,在高分辨率成像、粒子捕获和操纵等方面具有潜在的应用前景。更多还原

【Abstract】 In this paper,a free-space vortex generator based on Bessel beam diffraction is designed.The Bessel beam propagates in a single-mode fiber(SMF) through a spiral phase disk at the end of the fiber,and then evolves into a vortex beam,which is modulated in free space.The finite-difference time domain(FDTD) software is used to analyze the generator’s operating wavelength range,polarization sensitivity and processing tolerance.Comparing the results of the vortex beam with different topological values propagating in the free space for 100 μm,the proposed fiber vortex generator has the non-diffractive properties of the Bessel beam naturally obtained in the fiber,which can produce a specific Bessel beam.The beam has potential applications in high-resolution imaging,particle capture and manipulation.更多还原