Dual-band lasing of benzopyran dyes in the red region of the spectrum

We have studied the spectral and energy characteristics of lasing for two benzopyran dyes in a dispersive cavity with a diffraction grating when the dyes are excited at several different wavelengths using an additional flashlamp-pumped dye laser. These dyes have high fluorescence quantum yield and lase efficiently in the red region of the spectrum. The tuning range of their lasing spectrum is greater than 100 nm. We discuss the characteristic features of conversion of the selective excitation energy by these dye molecules. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 401–404, May–June, 2006.