Optical system for homogenizing semiconductor laser beam of area array

Abstract

The invention provides an optical system for homogenizing a semiconductor laser beam of an area array, which comprises a semiconductor laser of the area array, a collimating lens array, a first microlens array, a second microlens array, a slow-axis field lens and a fast-axis field lens, wherein the semiconductor laser of the area array is positioned on the front focal plane of the micro collimating lens array and takes an output laser beam of the semiconductor laser of the area array as a system optical axis; the first microlens array, the second microlens array, the slow-axis field lens and the fast-axis field lens are positioned on the optical axis in sequence and are vertical to the optical axis; and a multi-mode laser beam sent by the semiconductor laser parallelly enters after being collimated by the collimating lens array and then is evenly divided into a plurality of sub beams by the first microlens array to be focused on the rear focal plane, and afterwards, the sub beams are overlaid on the rear focal plane of a field lense by the the second microlens array, the slow-axis field lens and the fast-axis field lens, that is to say, the sub beams are overlaid on the lighting surface. The homogenizing of the semiconductor laser beam is realized by a cylinder-shaped Fresnel diffraction microlens array, so that the quality of the beam is improved.

Description

technical field [0001] The invention relates to the field of laser technology, in particular to an optical system for homogenizing an area array semiconductor laser beam by using an array composed of a plurality of cylindrical Fresnel microlenses. Background technique [0002] Semiconductor lasers are widely used in welding, annealing, cutting, drilling, micro-processing, military, medical and other fields, which have high requirements for the shape, power density, uniformity and stability of the laser beam. Therefore, homogenizing the semiconductor laser beam has become a necessary technical means. [0003] At present, there are two main methods for homogenizing semiconductor laser beams: one is the waveguide method, and the other is the microlens array method. The former is not affected by the energy distribution and fluctuations of the incident beam, but the brightness of the beam after homogenization is low, and the system has many components and is large in size, makin...

AI Technical Summary

Problems solved by technology

The former is not affected by the energy distribution and fluctuations of the incident beam, but the brightness of the beam after homogenization is low, and the system has many components and large volume, which is not easy to integrate and assemble

The latter is mainly composed of a collimator lens, an aspheric microlens array, and a Fourier lens. The system has fewer components, is small in size, easy to integrate, and has a high spot energy density. However, it is very difficult to manufacture a refractive aspheric microlens array, and the production cost very high

In addition, due to the limitations of the process, the ordinary refractive aspheric microlens is difficult to miniaturize its aperture unit and has a transition area, resulting in low energy utilization and poor uniformity.

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