Abstract
A simultaneous two-wavelength dye laser was developed as a flashlamp pumped one, and applied to a DIAL system. As tuning elements, dielectric multilayer filters were used in laser cavities. The widths and intensities of. spectra in the filter tuning were half and doubled respectively, as compared with those of a doubleprism tuning. Maximum intensities were obtained as the temperature of the dye solution was 15-16°C, and at that time the temperature difference between the dye solution and the cooling water was -0.4--1.0°C. Simultaneous two-wavelength DIAL system was constructed by using this dye laser, and the difference of absorption cross-section of 1.6 x 10-23 m2 was obtained for NO2 at a pair of wavelengths 463.1 nm (on-resonance) and 465.8 nm (off-resonance). In the field test, the NO2 concentration of 7ppm was observed with 75m range resolution by averaging 50 signals at the center of a stack plume.
