摘要
当808 nm的红外激光通过YAG晶体时,激光泵浦Nd:YAG产生的热效应使晶体发热量很大,要求对YAG晶体制冷的TEC的最大功率为144 W.当946 nm的红外激光通过LBO晶体时,要求对LBO晶体制冷的TEC的最大功率为30 W,现有的一些专门的TEC控制芯片均无法达到以上所述电流及功率.可以用弱信号控制强电流并且其灵敏度高,切换速度快(可达1 ms),无机械运动零部件,寿命长,可靠性高,开关过程中没有抖动.在如上所述制冷量如此大的情况下采用固态继电器驱动TEC工作,只要选择合适的电源,并配合相应的PID软件控制就可以控制Nd:YAG晶体温度波动在±0.375℃.LBO晶体温度波动在±0.250℃.在除湿环境中,激光器可以稳定输出1.6 W的蓝光.
When 808 nm infrared laser passes through the YAG crystal,the YAG will be highly heated by the heat effect from Nd：YAG laser pump.Therefore,it is required that the maximal power of TEC,which cools YAG crystal,be 144 watts.When 946 nm infrared laser passes through LBO crystal,the maximal power needed for LBO crystal is 30 watts.However,the currently available control chips in TEC cannot provide so large current and power.The SSR can control large current using weak signal.In addition,SSR possesses so many advantages： no mechanical components,no fluctuation in the switching process,high sensitivity,high switching speed,high reliability and long service life.Hence SSR is preferred to be used as TEC driver when the cooling power is very large.If appropriate power and PID software control are selected,the temperature fluctuation of Nd：YAG crystal could be controlled within the range of 0.375 ℃,and the temperature fluctuation of LBO crystal within the range of 0.250 ℃.Under the humidityfree environment,the laser can steadily output the blue light of 1.6 watt.
出处
《应用科技》
CAS
2007年第9期46-49,共4页
Applied Science and Technology
