Generation of a red-green-blue laser by stimulated Raman scattering of ethanol

In this paper, we report an efficient red-green-blue (RGB) laser based on the stimulated Raman scattering (SRS) of ethanol. The wavelengths of the three-color laser are 631, 532, and 447 nm, respectively, and the gamut space that can cover is 116% of the Rec. 2020 standard gamut in the CIE1976 color space. The maximum output energy of the RGB laser was 595.9 µJ under the total pump energy of 1.56 mJ, which corresponds to an optical conversion efficiency of 38.2%. By adjusting the energy ratio of different wavelengths, a white laser output with a maximum output energy of 544.8 µJ is achieved, corresponding to a conversion efficiency of 34.9%. To the best of our knowledge, this is the first time that an RGB laser has been realized based on liquid SRS. It provides a simple, practical route for efficiently obtaining RGB and white lasers, which may find important applications in many fields like laser display, atmospheric monitoring, and medical beauty.