We theoretically investigate the tight focusing of radially polarized circular partially coherent (RPCPC) beams through a high numerical aperture objective. The sub-wavelength super-long optical needle and dark channel can be obtained near the focus, by engineering the source coherent length of the incident RPCPC beams. The length of the optical needle and the dark channel can be adjusted, and the obtained maximal lengths of the optical needle and the dark channel are both 22λ. The full width at half maximum of the optical needle and the dark channel are 0.6λ and 0.48λ, respectively.
Abstract
CP-K 570Y780T is one of a family of complex-phase steels, CP-W and CP-K, that offer very high strengths and yield points. They are particularly suitable for weight-saving production of cold-formed, crash-relevant automotive components such as side impact intrusion beams, B-pillar reinforcements,profiles, cross members, body reinforcements, bumper bars, and chassis parts. This datasheet provides information on composition, hardness, and tensile properties. It also includes information on heat treating. Filing Code: SA-848. Producer or source: ThyssenKrupp Steel Europe AG.
Generation of optical needle and dark channel by tight focusing of radially polarized circular partially coherent beams
