This paper reports the laser action in nine styryl dyes which were newly synthesized over a tunable range from 698 to 890 nm. These dyes showed the same or better performance than those of traditional styryl dyes in the same wavelength range for the pumping by a frequency-doubled Nd: YAG laser. The optimum concentration, efficiency and tunable range were measured for 532 nm and 308 nm pumping, and their dependence on the chemical structure is briefly discussed.
We have constructed an interferometric spectrometer in millimeter and submillimeter range (2_??_11cm-1). It consists of a continuous light wave source from a backward wave oscillator and its frequency multipliers, a symmetric Mach-Zehnder type interferometer, and a detection system. Analytical methods were developed to obtain optical constants rapidly and accurately. The refractive index and extinction coefficient were measured for several materials and the characteristics of the constracted spectrometer were evaluated.