Increase in the Lasing Efficiency of Thin-Film Lasers Based on 1.4- Distirylbenzene

The possibility of development of a thin-film 1,4-distirylbenzene–based laser lasing in the blue spectral range in solutions and films is investigated. The stimulated emission of 1,4-distirylbenzene in a polymethylmethacrylate film with transverse pumping by a YAG-Nd3+ laser is obtained for the threshold power density W = 0.44 MW/cm2. It is shown that incorporation of the additional amorphous SiO2 layer, improving the condition of total internal reflection on the boundary of the active medium, decreases the lasing threshold to 50–70 kW/cm2; in this case, the efficiency of radiation conversion is equal to 20%.