小型长波红外光栅光谱仪光学设计

光学系统是光谱仪微小型化的关键,光学设计的质量将直接影响微小型光谱仪的性能.针对长波红外光谱探测的具体应用,对比国内外各种方案,分析其优劣后提出一种基于交叉非对称切尔尼-特纳(Czerny-Turner)结构的小型光栅光谱仪.首先根据光谱仪基本原理和光学设计理论,分析系统的光谱分辨率、像差以及探测灵敏度.然后以小型化、低成本、要求的光谱范围和分辨率为具体设计目标,对系统进行优化设计.最后在光学软件Zemax中进行模拟和优化.设计结果表明:该系统的光谱范围为8～14μm,光谱分辨率优于80nm,光学系统尺寸约为100mm×75mn×45mm,满足小型化要求.同时采用扫描光栅配合单通道探测器的方式降低成本.

Optical Design of a Miniature Long-Wave Infrared Grating Spectrometer

Optical system is the key to the miniaturization of spectrometer,which directly affects the performance and accuracy of a miniature spectrometer.After comparing different optical systems,a miniature long-wave infrared grating spectrometer based on cross-asymmetric Czerny-Turner structure is proposed for the purpose of long-wave infrared spectrum detection.First,based on the principle of spectrometer and the theory of optical design,the spectrometer’s spectral resolution,aberration,and detection sensitivity are studied.Then the optical system is optimized for goals of small size,low cost,required spectral range and resolution.Finally,the optical system is simulated in Zemax software.The results show that the spectrometer’s spectral range is 8～14μm,and the spectral resolution is better than 80 nm,and the volume of the optical system is approximately 100 mm×75 mm×45 mm,which satisfies the requirements of miniaturization. A scanning grating and signal cooled detector are used to reduce costs.