Design and fabrication of a double-axicon for generation of tailorable self-imaged three-dimensional intensity voids

School of Electrical and Electronic Engineering, Nanyang Technological University, Tumasik, 00, Singapore
Optics Letters (Impact Factor: 3.18). 05/2006; 31(7):987-9. DOI: 10.1364/OL.31.000987
Source: PubMed

ABSTRACT We propose a new design for fabrication of a highly power-efficient double axicon to generate self-imaged three-dimensional intensity voids along the propagation of a beam. The conventional conical structure of an axicon is modified and shaped like an axiconlike structure with a double-gradient surface profile. The gradient conical surfaces generate Bessel beams with varying radial wave vectors that are superimposed and interfere to generate a sequence of three-dimensional intensity voids. The proposed element was fabricated using electron-beam lithography, and experimental verification of the design is reported.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Based on the vector diffraction theory, the effect of complex phase plate on the intensity distribution of TEM11 mode azimuthally polarized Laguerre–Gaussian beam in the focal region of high NA lens is investigated theoretically. It is observed that a properly designed complex phase plate can generate a subwavelength focal hole having FWHM of 0.332λ with an extended focal depth of 54.4λ. We also observe that by using properly designed complex phase plate generates novel focal patterns including splitting of focal holes and multi focus are obtained. The author expects such investigation is worthwhile for optical manipulation and material processing technologies.
    Optik - International Journal for Light and Electron Optics 08/2014; 125(15). DOI:10.1016/j.ijleo.2014.03.002 · 0.77 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: An improved iterative approach is proposed to design a diffractive axicon with long focal depth and high lateral resolution. Model designs of the diffractive axicon are carried out in order to convert multi-wavelength uniform beam and Gaussian beam into long focal depth focusing. The numerical results indicate that the designed axicon can achieve long extended focal depth, high transverse resolution and diffraction efficiency simultaneously. Furthermore, a uniform plateau profile can be obtained by using multiple weighted algorithm. The axicon that generates two preset focal depths has been designed, which can also exhibit two perfect long focal depths.
    Optics Communications 11/2014; 330:1–5. DOI:10.1016/j.optcom.2014.04.061 · 1.54 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report a theoretical investigation of the tight focusing properties of spatial-variant vector beams with localized linear polarization. By using the Richards-Wolf vectorial diffraction method, we obtain expressions for the three-dimensional (3D) electric field in the focal region of the high numerical-aperture (NA) objective. We systematically study the dependence of the focal volume shapes on the azimuthal topological charge, the radial topological charge, the pupil filling factor, as well as the value of NA. By manipulating the azimuthal and radial topological charges of the vector beam simultaneously, we obtain a controllable 3D optical bottle, optical bubble, and twinborn focal rings alone the optical axis in the focal volume of a high NA objective. These particular focal fields may be of interest for applications in optical trapping and manipulating micro-particles.
    01/2014; 43(1). DOI:10.1007/s12596-013-0154-9