Zhu X, Schülzgen A, Wei H, Kieu K, Peyghambarian N
College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, USA.
Opt Express. 2011 Jun 6;19(12):11365-74. doi: 10.1364/OE.19.011365.
Micron-sized white light propagation invariant beams generated by a simple and compact fiber device are presented. The all-fiber device is fabricated by splicing a short piece of large-core multimode fiber onto a small-core single mode white light delivery fiber. Because this fiber device offers an inherent spatial coherence, nondiffracting white light beams can be created with a temporally incoherent broadband light source (a halogen bulb) and, most importantly, the surrounding fringes don't fade as the bandwidth of the light source increases because the underlying physics of this fiber device is different from that of the axicon. White light Bessel-like beams have been generated from multimode fibers with core diameters of 50 μm, 105 μm, and 200 μm. The distance of nondiffracting propagation of the white light Bessel beam increases with increasing core size of the multimode fiber. Propagation characteristics of red, green, and blue individual beams are also presented.
介绍了一种由简单紧凑的光纤装置产生的微米级白光传播不变光束。该全光纤装置是通过将一小段大芯多模光纤熔接到小芯单模白光传输光纤上制成的。由于这种光纤装置具有固有的空间相干性，因此可以使用时间非相干宽带光源（卤钨灯）产生无衍射白光光束，而且最重要的是，随着光源带宽增加，周围条纹不会褪色，因为这种光纤装置的基本物理原理与轴棱锥不同。已从芯径为50μm、105μm和200μm的多模光纤中产生了类白光贝塞尔光束。白光贝塞尔光束的无衍射传播距离随多模光纤芯径的增大而增加。还介绍了红、绿、蓝单光束的传播特性。
