Topic
Bessel beam
About: Bessel beam is a research topic. Over the lifetime, 1946 publications have been published within this topic receiving 42264 citations.
Papers published on a yearly basis
Papers
More filters
•
18 Dec 2003
TL;DR: In this article, a relativistic electron beam is converted to a Bessel beam in an FEL resonator with conical end mirrors and coupled to the optical field within the laser resonator.
Abstract: Methods and apparatus are provided for modifying a free electron laser (FEL) to produce a non-diverging laser beam. A relativistic electron beam is converted to a Bessel beam in an FEL resonator with conical end mirrors, and the Bessel beam is coupled to the optical field within the laser resonator. The resultant laser beam is propagated with minimal divergence, and is wave corrected at the resonator output to produce a uniform intensity circular beam. The laser beam can be of smaller diameter than that of a conventional resonator due to its diffractionless propagation, which enables the magnetic structure gap within the resonator to be smaller, thus producing a higher optical gain.
2 citations
••
2 citations
••
19 Nov 2015
TL;DR: In this paper, it was shown that at low levels of a random roughness of a reflecting surface, the degree of coherence of a vortex Bessel optical beam essentially depends on value of a topological charge of an optical beam.
Abstract: Researches of coherent properties of the vortex Bessel optical beams propagating in a uniform medium after reflection from a rough surface are developed. It is shown, that at low levels of a random roughness of a reflecting surface, the degree of coherence of a vortex Bessel optical beam essentially depends on value of a topological charge of an optical beam. In the central part of a two-dimensional field of degree of coherence the ring dislocation is formed, the number of rings in which is equal to value of a topological charge of a vortex optical beam. At high levels of a random roughness of a reflecting surface, mutual coherence function of a vortex Bessel optical beam coincides with the similar characteristic of an incoherent source.
2 citations
••
13 May 2018TL;DR: In this paper, a quasi-Bessel beam with a ∼14mm Bessel length and ∼30 μm FWHM was generated using a splitter-tree-based architecture.
Abstract: Generation of Bessel beams using integrated optical phased arrays is proposed and experimentally demonstrated for the first time. A quasi-Bessel beam with a ∼14mm Bessel length and ∼30 μm FWHM is generated using a splitter-tree-based architecture.
2 citations
••
TL;DR: In this article , a position-controllable Bessel beam is integrated into the LLSM to achieve spatiotemporal photoactivation by changing the spatial light modulator (SLM) patterns.
Abstract: Abstract Lattice lightsheet microscopy (LLSM) featuring three-dimensional recording is improved to manipulate cellular behavior with subcellular resolution through optogenetic activation (optoLLSM). A position-controllable Bessel beam as a stimulation source is integrated into the LLSM to achieve spatiotemporal photoactivation by changing the spatial light modulator (SLM) patterns. Unlike the point-scanning in a confocal microscope, the lattice beams are capable of wide-field optical sectioning for optogenetic activation along the Bessel beam path.We show that the energy power required for optogenetic activations is lower than 1 nW (or 24 mWcm -2 ) for time-lapses of CRY2olig clustering proteins, and membrane ruffling can be induced at different locations within a cell with subcellular resolution through light-triggered recruitment of phosphoinositide 3-kinase. Moreover, with the epidermal growth factor receptor (EGFR) fused with CRY2olig, we are able to demonstrate guided cell migration using optogenetic stimulation for up to 6 h, where 463 imaging volumes are collected, without noticeable cellular damages.
2 citations