摘要
不同气体分子由于其特征结构不同,对应于不同的吸收光谱,通过气体对特定波长光的吸收,形成了光谱吸收式气体传感器。在光谱吸收式气体浓度检测系统中,保证半导体激光器输出光波长的稳定性是最为重要的,而激光器的温度是影响输出波长的主要因素之一。目前,通常采用激光器内部的热敏电阻器作为激光器温度的测量依据,但受到激光器结构的限制热敏电阻器不能精确快速地指示激光器的温度,影响了检测系统的正常工作。为了解决这个问题,通过对垂直腔面发射半导体激光器应用的分析,在原有热敏电阻器的基础之上,加入对激光器输出波长的监测,形成了热敏电阻器与输出波长的双重检测的温度控制方案,改变传统的仅有热敏电阻器单参数的温度控制方案,形成双参数的数字PID控制决策,实验结果表明:光源温度偏差可以控制在0.01℃以内,进一步提高了光学气体传感器的工作稳定度。
Different gas molecule has different absorption spectrum due to different characteristic structure,spectrum absorption gas sensor is produced by absorption of specific wavelength.In spectrum absorption gas concentration detecting system,it is important to ensure stability of output wavelength exported by semiconductor laser,and temperature of laser is one of the major factors affecting wavelength.At present,thermistor inside laser is used to measure temperature of laser,but the structure of thermistor confines measurement can not to be accurate and fast,so the detection is not able to work well.To solve this problem,through analysis on application of vertical cavosurface launching semiconductor laser,on the basis of previous thermistor,monitoring of the wavelength exported by laser is added.So the temperature control scheme based on double detection of thermisor and output wavelength is proposed,and the traditional temperature control scheme only depends on one-parameter of thermisor is changed,at last the digital PID control of two parameters is formed.Experimental results show that the temperature deviation can be controlled at 0.01 ℃,and the working stability of optical gas sensor is improved.
出处
《传感器与微系统》
CSCD
北大核心
2013年第6期43-46,共4页
Transducer and Microsystem Technologies
基金
中央高校基本科研业务费专项资金资助项目(DL11BB17)
