Novel result on geometry character of laser beam

摘要

In this paper, some research results on the geometry characters of laser presented, mainly including that the streamline structure and the spot size of laser beam. A phenomenological model for the streamline structure of laser beam proposed, of which the main point is that a Gaussian beam is divided into two regions in which the streamline structure appears different geometry characters. Also a quantum interpretation on how the beam waist comes into being and the energy shifts between the two regions given. This model meets very well with experimental results. Another work reported in this paper is detecting the laser spot size, for that a new method found. By the approach of the so-called "pre-saturation" in silicon, the novel laser spot size detector with monocrystalline silicon designed and demonstrated right and doable experimentally. This new detector can detect the size of laser beam spot quickly and accurately, with wide response wavelength band and quite small expense.