【摘要】 采用双声光调制器光路快速偏转技术与自准直光栅法实现CO₂激光全波段快调谐同光路输出。首先对声光调制器特性进行实验研究,结果显示:声光调制器偏转角度约为4. 4°,与运用布拉格方程计算结果相符;且激光单次通过声光调制器移频量为40. 68 MHz,与声光驱动器射频频率一致,将激光往返多次经声光调制器的移频量叠加。进而,开展基于声光调制器的CO₂激光快调谐实验研究,运用两个对称布置的同驱动频率声光调制器补偿声光移频,实现偏转光路振荡输出,运用光栅法在直线光路中实现激光全波段可调谐输出。最终,在声光调制器时序控制下,实现双波长激光快调谐同光路输出,选定激光波长的切换时间约为1 ms,脉宽小于300 ns,且双波长切换速度不受CO₂激光跃迁谱带的限制。更多还原

【Abstract】 A rapid tuning pulsed CO₂ laser is presented using a blazed grating system and a pair of acousto-optic modulators. Firstly,the characteristics of acousto-optic modulators were studied through experimentation.The results showed that the deflection angle of the acousto-optic modulator was approximately 4. 4°,which wasin agreement with the calculations of the Bragg equation. When a single laser passed the acousto-optic modulator,the shift in frequency was approximately 40. 68 MHz,which was in agreement with the acousto-optic driving frequency. In addition,when multiple lasers passed through the acousto-optic modulator,the shift in frequency was compounded. Based on the acousto-optic modulator results,experimental research was performed on rapid tuning pulsed CO₂ lasers. In order to offset the shift in acousto-optic frequency,two acousto-optic modulators were placed symmetrically in the deflected optical beam,and a laser output was obtained. Using a blazed grating,a full band tunable output laser was obtained in the linear optical beam. Finally,under sequential control of double acousto-optic modulators,a double wavelength laser with rapid tuning output and a common optical axis was obtained. The tuning time of the pulsed laser was approximately 1 ms,which pulsed at a width of less than 300 ns. The tuning speed of the pulsed laser was independent of the transition band of the CO₂ laser.更多还原