Yajun Li

TL;DR: In this paper, it was shown that when the incident wave is uniform and the angular semi-aperture is small, the ratio of the point of maximum intensity to the distance between the geometrical focus and the plane of the aperture depends only on the Fresnel number N of the image when viewed from the focal point.

TL;DR: In this article, a simple sufficiency condition is obtained, under which the Debye diffraction integral may be expected to give a good approximation to the solution of a boundary value problem that is generally taken to represent a field in the region of focus.

TL;DR: In this paper, the point of maximum intensity in a focused aberration-free wave is not at the geometrical focus, but is closer to the focusing lens, where the waist of the beam is assumed to be located in the aperture plane.

TL;DR: It is found that with an appropriate choice of the source parameters the radiantintensity may be rotationally symmetric about the source plane and may even become identical with the radiant intensity produced by a completely coherent and rotationally asymmetric laser source.

TL;DR: The propagation features of this new set of optical beams are investigated to reveal how a windowed Bessel beam passes progressively from a smooth Gaussian window toward the hard-edge limit.