低热效应高光束质量自倍频黄光激光器

Abstract

The development of selffrequency doubling lasers has been significantly limited owing to the thermal effect.To reduce the thermal effect of lasers and obtain higher beam quality yellow laser output, a Yb∶ YCOB selffrequency doubling crystal yellow laser pumped by a 1020 -nm laser is proposed. The influence of the thermal lens effect, because of the selffrequency doubling crystalabsorbing pump light energy, on the phase matching condition during the process of optical frequency doubling is explained on the basis of a theoretical analysis. Furthermore, the analysis also yields an explanation for the improvement in the quality of the 1020 -nm singleband pumping mode beam, as compared with that of the traditional 976 -nm laser diode pumping mode. A 570 -nm yellow laser with higher beam quality is obtained through experiments. The beam quality factors correspond to M 2 x = 1. 41 and M 2 y = 1. 87. The results indicate that the quality of the outgoing beam at a wavelength of 1020 nm is significantly higher than that at 976 nm, and the spectrum width is narrower. The results of the study play a guiding role in reducing the thermal effect of Yb∶ YCOB selffrequency doubling lasers and obtaining highpower yellow lasers with higher beam quality and narrower spectrum width.