Laser welding inspection visual sensor 405 nm wavelength semiconductor laser line light source

In response to the significant challenges posed by the width and uniformity of illumination from visual sensors during the inspection of sharp corner welds, high-speed welding, and the welding of highly reflective materials in the laser welding process, the influence of line laser width on inspection accuracy was analyzed in this paper. To meet the requirements of narrow width and high uniformity, a line laser shaping design based on a Diffractive Optical Element (DOE) and a Powell prism was proposed. The light generated by a semiconductor laser with a wavelength of 405 nm was shaped into an ideal Gaussian beam using a DOE after beam expansion and collimation, and subsequently shaped into a line laser using a Powell prism. A model was constructed to simulate the aforementioned process, and corresponding experiments were designed to verify the relationship between line laser width and inspection accuracy. The results showed that after passing through the DOE, the M ² factors of the Gaussian beam in the x-direction and y-direction were 1.040 and 1.038, respectively, with Rayleigh lengths of 316.1 mm and 321.1 mm. After shaping by the Powell prism, the beam width at a distance of 150 mm from the prism was 19.433 mm, with a uniformity of 96.93%, satisfying the requirements of narrow width and high uniformity for the illumination source in line laser vision sensors.