摘要
报道一种工作于可见和紫外波段的脉冲激光光声装置 .该装置以YAG泵浦的染料激光为光源 (脉宽为8ns ,工作频率为 10Hz) .用此装置记录了C2 H2 分子的泛频激发谱和A1Au←X1Σ+ g 电子跃迁谱 ,并测量了光声强度随气体压力及激光能量的变化关系 .将光声谱用于分子的电子跃迁 .由于脉冲激光光声装置和实验操作十分简便 ,因而除需超高分辨的场合外 ,它均可用来代替共振 (或非共振 )调制cw激光光声装置 .
A pulsed laser photoacoustic (PA) instrument operating under visible and ultraviolet range was reported, which used a YAG pumped dye laser (width 8 ns, repetition rate 10 Hz) as the light source. Photoacoustic spectra of C2H2 overtone excitation and A(1)A(u) <--X-1&USigma;(+)(g) electronic transition were obtained using the instrument and the dependence of PA signal intensity on the sample pressure and the laser energy was measured. The application of pulsed PA to electronic transition was less reported before. Because, of the simplification of its theoretical treatment and experimental operation, the pulsed PA instrument can replace resonant ( or non-resonant) moderate cw PA instrument in almost all the cases except the ultra high-resolution spectroscopy. The difference between pulsed and cw moderate PA was also discussed in the text.
基金
国家自然科学基金资助项目 (2 98730 4 7)
973项目 (19990 75 30 4 )
