傅里叶红外光谱仪分束器自动装调系统设计

摘要

为了提高傅里叶红外光谱仪干涉系统的精度,设计了一种基于一体化分束器的自动装调系统.使用光学胶水将棱镜与分束器固定在一起组成一体化分束器,在一体化分束器上设置三点调整机构,O点位置进行固定作为参考点,在X点、Y点位置装入压电陶瓷,利用压电陶瓷驱动分束器进行微小位移的调整.在动镜匀速运动的情况下,利用四象限检测器检测三路携带相位差信息的信号,对信号进行放大滤波和数字化处理后,采用DSP的ECAP模块捕捉三路相位差信号,并利用增量式PID算法根据相位差来对三个点位的调整幅度进行实时控制,使用DSP的AD模块采集三路信号,并利用USB2.0与上位机进行通信,在上位机上实时显示三路信号图形及相位差信息.利用光学胶水的紫外固化特性,在支架上安装紫外照射灯,调整过程中不断增加照射强度使光学胶水进行深度固化,从而制作出符合傅里叶变换红外光谱仪应用需求的一体化分束器.实验结果表明,所设计的基于一体化分束器的自动装调系统具有结构简单,调整精度高等优点,其能够满足常规红外分束器装调需求.%In order to improve the accuracy of interference of Fourier transform infrared spectrometer,we design an automatic regulating system based on integrative beam splitter.Using optical glue to fix the prism and beam splitter.Three adj ustment structures was set on the integrative beam splitter.The O point is fixed as the reference point,and piezoelectri ceramics are load-ed on the X point and Y point.Using the piezoelectri ceramics to drive beam splitter for tiny displacement adj ustment.When the moving mirror moves in constant speed,using four quadrant detector to test the phase difference of three signals.Then three signals are enlarged,filtered and digitized.Using the ECAP of DSP to catch three signals and Using the increment PID to con-duct real time control the adj ustment of three signals based on phase difference.These three signals is sampled by the AD of DSP.All the information measured can communication with the host PC through USB2.0,then finally reading collection data and real-time demarcating the wave show.The ultraviolet radiator is installed on the holder,the irradiation of ultraviolet light on optical glue is increased when the aj ustment start.So that the integrative beam splitter is made which can meet the demand of fourier transform infrared spectrometer.The experimental results show that the design of automatic regulating system based on integrative beam splitter has advantages of simple structure,high adj ustment accuracy which can meet the demand of common in-frared beam splitter.