用于连续波腔衰荡法测量的LD驱动电路设计

为了将半导体激光器应用于连续波腔衰荡法腔损耗测量,设计了半导体激光器的驱动电路.该电路由调制、驱动、温控等模块组成,在采用多光束干涉理论对连续波腔衰荡法测量原理进行分析和数值模拟的基础上,提出了驱动电路各模块的参数要求,对该电路各参数进行测试后,应用该电路建立了连续波腔衰荡法腔损耗测量系统,并进行了实验.经测试得知,在保证半导体激光器安全工作的前提下,该电路对于半导体激光器的关断时间约为60ns,对半导体激光器的温度控制精度优于0.01℃;对某单程腔损耗约为50×10-6的衰荡腔测试表明,腔损耗测量精度优于1%.结果表明,该电路达到理论设计要求,可应用于高精度腔损耗测量.

Design of driving circuits of semiconductor lasers for measurement of continuous-wave cavity ring-down technology

In order to apply semiconductor laser to measure cavity loss with continuous-wave cavity ring-down technology,the laser diode's driving circuit was designed. The circuit was composed of different modules,such as modulation,driver and temperature controller. Based on theory of passive cavity's multi-beam interference,modules' parameter demand was suggested after analysis and numerical simulation of ring-down signal. The measurement system of cavity loss was built with the circuit.Under the guarantee of the semiconductor laser trouble-free,tests indicated that the shutoff time of laser diode was about 60ns and the precision of temperature controller was better than 0.01℃. The measuring accuracy was better than 1 % for a cavity whose single pass loss is about 50 × 10－6. Results indicate that the circuit meet the theory design demands and can be applied in high-accuracy measurement of cavity loss.