Partially Coherent Flat-Topped Beam Generated by an Axicon

Abstract

The intensity distribution of a partially coherent beam with a nonconventional correlation function, named the multi-Gaussian Schell-model (MGSM) beam, focused by an axicon was investigated in detail. Our numerical results showed that an optical needle with a flat-topped spatial profile and long focal depth was formed and that we can modulate the focal shift and focal depth of the optical needle by varying the width of the degree of coherence (DOC) and the parameters of the correlation function. The adjustable optical needle can be applied for electron acceleration, particle trapping, fiber coupling and percussion drilling.

Engineering a better light sheet in an axicon‐based system using a flattened Gaussian beam of low order

“…Its bell-shaped distribution can mathematically be approximated by a Gaussian function that is depicted with the scalar wave equation. Meanwhile, state-of-the-art beamshaping methods enable users to overcome many of the limitations that we encounter by remaining in the Gaussian regime [2,36,[39][40][41][42]. Meso-aspheric elements such as Powell lenses, axicons, and multi-cylindrical-conic lenses can convert an approximately Gaussian beam into, for example, a diffraction-limited Bessel beam/Mathieu beam, Mathieu-Gauss beam, extended homogeneous line beam, or a light-sheet of controlled expansion.…”

Tight focusing of azimuthally polarized Laguerre–Gaussian vortex beams by diffractive axicons

“…Axicons have garnered significant interest in recent years due to their versatility in generating a wide range of beam shapes in the focal region [1][2][3][4]. Linear or classical axicons, which exhibit a linearly increasing on-axis intensity along the optical axis, have proven effective for creating non-diffracting Bessel beams [1,5] and producing diverse focal shapes, including double focal spots [3], flat-topped beams [6], three-dimensional dark spots [7], thin light sheet [8], and very tight focus [9,10]. As a result, linear axicons have found applications in long-range alignment [11], laser machining [12], Bose-Einstein condensates [13], and particle manipulation [14].…”

Intensity distribution of the partially coherent Gaussian Schell vortex beam diffracted by classical axicon

“…Axicons have attracted increasing attention because of their diversity and utility in generating various significant beam shapes within the focal region [1][2][3][4]. The classical axicon, characterized by an on-axis intensity linearly increasing along the optical axis, has been employed for the creation of non-diffracting Bessel beams [5], as well as for producing diverse focal shapes, such as hollow laser beams [6], double focal spots [4], thin-sheet lights [7], tight focal spot sizes [2], flat-topped beams [8], and three-dimensional dark spots [9]. As a result, the linear axicon has been recognized as a crucial optical component in long-range alignment [10], laser machining [11], Bose-Einstein condensates [12], and particle manipulation [13].…”