Laser diode array beam shaping system based on fly's eye lens

Abstract

The main drawback of diode laser array is the inhomogeneous intensity distribution in the far field. So the beam shaping technology is very important in the application of laser diode array. This work present a novel beam shaping optical system based on fly’s eye lens. The system can homogenize the diode laser array based on the multi-aperture beam integrating theory. Such beam shaping system was designed by ray tracing method using ZEMAX™ Non-Sequential Components analysis tools. The ray-tracing simulation shows that a 5 × 5 mm2 Top-Hat intensity profile was got at a working distance of 40 mm and the homogeneity of the intensity distribution is better than 90%. And it is verified that such beam shaping system is adapted for the aberrations of bars very well by simulation. Based on the design, a relative experimental research on the beam shaping system for 5 bars LD stack is carried out. Through the beam shaping system the laser diode power intensity is improved 4 times, light field distribution nonuniformity is less than 10%, and the system coupling efficiency is more than 80%, which validated the engineering feasibility and applied value of this novel LD array beam shaping system.