高分辨率宽光谱范围微型光谱仪的设计与分析

Design and Analysis of Micro-Spectrometer with High Resolution and Wide Spectral Range

针对微型光谱仪难于兼顾光谱分辨率和光谱范围的问题,提出一种级联微型法布里-珀罗干涉仪和微型曲面光栅光谱仪的设计方法。分析了两种光谱仪匹配设计的条件以及级联光学系统的光谱特性,并提出了一种光谱数据重构算法。用ZEMAX软件设计了一款激光拉曼光谱仪,该光谱仪的尺寸为25mm×6mm×6mm,数值孔径为0.22,拉曼光谱范围为150〜3200cm^-1光谱分辨率约为6cm^-1。仿真了标准拉曼光谱信号的扫描过程,并用长度为2.4mm的线阵探测器对光谱信号进行采样,重构的拉曼光谱分辨率约为6.4cm^-1,与标准拉曼光谱的偏差为0.4cm^-1,验证了该设计方法和重构算法的可行性。同时,该光谱仪可以基于微机电系统工艺实现微型化和低成本化,满足手持式、便携式光谱检测和工业在线光谱检测的应用需求,具有较高的实际应用价值。

Aiming at the problem that it is difficult for micro-spectrometer to take into account both spectral resolution and spectral range,a design method of cascade Fabry-Perot interferometer and micro curved grating spectrometer is proposed in this paper.The matching conditions of the two spectrometers and the spectral characteristics of the cascade optical systems are analyzed,and a spectral data reconstruction algorithm is proposed.A laserRaman spectrometer is designed with ZEMAX software.The spectrometer has a size of 25 mm×6 mm×6 mm,a numerical aperture of 0.22,a Raman spectrum range of 150-3200 cm^-1,and a spectral resolution of about 6 cm^-1.The scanning process of the standard Raman spctrum signal is simulated,and the spectral signal is sampled with a 2.4 mm long linear array detector.The resolution of the reconstructed Raman spectrum is about 6.4 cm^-1,and the deviation from the standard Raman spectrum is 0.4 cm^-1.The feasibility of the design method and reconstruction algorithm are verified.At the same time,the spectrometer can be miniaturized and the cost can be reduced based on micro-electro-mechanical system technology,which can met the application requirements of hand-held,portable spectral detection and industrial on-line spectral detection,and has high practical application value.