反射式红外激光触发装置失稳现象分析与研究

Research and Analysis of Instability of Reflective Infrared Laser Trigger Device

针对红外触发装置在经过长时间工作之后出现失稳现象,在分析红外触发装置工作原理的基础上,通过实验监测和分析手段得出如下结论:红外触发装置经长时间工作后,因温度累积导致温度上升,引起红外激光触发装置的光源——红外激光器阈值电流Ith(T)上升,而温度升高同时引起激光光源驱动恒流源输出电流Iout(T)降低,当Iout(T)<Ith(T)时,红外激光器无法正常发出激光,输出功率不稳定,导致红外触发器失稳。在此研究基础上,通过提高恒流源的输出电流至最大阈值电流的1.44倍,即640 mA后,可保证在系统温度变化范围内,I out(T)>Ith(T),红外激光器始终处于稳定发光状态,从而使红外触发装置也处于稳定工作状态。经过长时间的上电运行验证实验,红外触发器工作稳定,未发生误触发信号,较好解决了其失稳问题。此研究对提高红外触发装置的稳定性有重要的工程应用价值。

In this study,the instability phenomenon of an infrared trigger device that has operated for a long period of time is examined on the basis of working principle of the device and by means of experimental monitoring and analysis.The threshold current,Ith(T),of the infrared laser,which is the source of the infrared laser triggering device,increases after the infrared trigger device works for a long time owing to heat accumulation.In contrast,the output current,Iout(T),of the constant current source decreases with the increase in temperature.When Iout(T)<Ith(T),the infrared laser cannot emit the laser normally,and the output power becomes unstable;this leads to the instability of the infrared trigger.Upon increasing the output current of the constant current source to 1.44 times the maximum threshold current,that is,beyond 640 mA to make Iout(T)>Ith(T),the infrared laser can be guaranteed to be in a stable luminous state within the range of temperature change,and the infrared trigger device is therefore in a stable working state.After a long period of power-on operation experiment,the infrared trigger worked stably and did not trigger the signal by mistake,indicating that its instability problem is effectively addressed.The findings of this study have important engineering application value in improving the stability of infrared trigger devices.