微型光谱仪系统的研究及其应用

【作者】 程梁；

【导师】 余飞鸿；

【作者基本信息】 浙江大学 ， 光学工程， 2008， 博士

【摘要】 光谱仪器是光谱与光谱分析学基本的分析工具,传统的光谱仪器由于体积庞大且价格昂贵,应用范围受到很大的限制,微型化成为其重要的发展方向。本论文研究并实现以光纤作为系统输入、可配置三种型号CCD和多种不同规格光学元件、工作在紫外可见和可见及近红外波段的系列化微型光纤光谱仪,并进一步研究了此类光谱成像系统的增益特性,提出静态双增益编码孔径色散光谱模型。在微型光纤光谱仪的电路与探测系统设计中,以相同的硬件同时完成三种型号CCD探测器的驱动,最大程度地精简了电路设计,这种设计在国内外同类仪器中尚属首次。同时,实现了TCD1304AP型号探测器10μs～4.9sec的积分时间调节范围,保证本系统能够满足大多数实际应用的需求,达到并超越了国外最新型此类仪器的水平。此外,在国内首次研究了常规CCD探测器紫外荧光增强方法,提出用于CCD表面荧光增强的荧光粉的性能参数要求及该技术的具体实现方法,保证本微型光谱仪能工作在紫外波段。在光学机械系统设计过程中,研究了基于平场全息凹面光栅和交叉非对称Czerny-Turner结构的两种光学系统。从理论上研究了平场全息凹面光栅的优化设计方法,首次引入全局搜索算法对非线性目标方程组进行求解,提高了收敛精度并缩短了设计周期;提出的反向优化和多工作位置的设计思想能提高设计的效率和现有此类光栅的使用灵活性。研究了基于Czerny-Turner结构的微型光谱仪光学系统的设计方法,对比分析选择后者作为本系统的基础光学结构。最后,论文充分利用CodeV、Tracepro和Solidworks等光学机械设计与模拟软件,完成了光谱仪光学机械系统和两类光谱测量附件的设计以及较为全面的系统公差分析。论文在软件系统设计部分,不仅完成了对光谱仪的全面控制和常规光谱测量功能,还以两种接口方式实现了二次开发工具箱,实现了软件系统的扩展功能,使整体系统具有更高的实用性和灵活性,达到国外此类仪器的水平。对实际系统进行全面测试,结果表明其性能优良,系列化程度高,具有很强的软硬件扩展性,整体性能达到并超过国外最新型同类产品。目前整个系统已经进入批量生产和销售。在成功研制微型光纤光谱仪的基础上,论文分析了此类系统增益受限的原因,提出使用具有正交独立列编码形式的扩展孔径代替传统狭缝,使得从叠加的成像光谱中还原单通道光谱成为可能,打破了狭缝对系统性能的限制,实现静态系统的双增益。进而设计了模拟系统对该模型可行性进行全面分析。大量分析结果证明,所提出的静态双增益编码孔径色散光谱模型完全可行,优化了传统色散成像系统的性能,对基于面阵探测器的微型光谱仪系统性能的提升具有革命性的意义。更多还原

【Abstract】 Spectrometers are the basic analysis instruments of optical spectroscope and spectral analysis. The applications of traditional spectrometers are constrained due to their big volume and high costs, miniaturization becomes to be their important developing direction. This dissertation carries the research on the micro spectroscopic system and realized a micro fiber spectrometer with a possible working wavelength range covers ultra-violet and visible or visible and near infrared region, within which three different models of CCDs and several types of optical components could be configured practically. Further research was carried to study the advantage characteristic of this kind of dispersive spectroscopic system and a novel static dual-advantage system model based on coded aperture was raised firstly.In the design of circuit and detecting system of micro fiber spectrometer, the drive of three different models of CCDs with the same circuit hardware was achieved which highly simplified the circuit design. This design method’s first applied among all existing similar instruments. An integrated time range of 10us～4.9sec for TCD1304AP linear CCD’s realized which could meet the needs for lots of applications. This characteristic reaches and exceeds the highest level of foreign instruments. Then firstly carried the research on UV surface fluorescence enhancing technique for common CCDs in China, represented the requirements of phosphor powder used for CCD UV enhancing and the realization method for this technique, which guaranteed that the micro spectrometer could normally and effectively work in UV range.In the research of optical and mechanical system, two kinds of optical structures for micro fiber spectrometers were studied. Firstly, the optimum design of flat-field holographic concave grating was studied theoretically, globe searching algorithm’s firstly introduced to solve the nonlinear equations set to increase the precision of the convergence and shorten the design cycle. The thought of anti-optimization and multi-working positions was raised to increase the design efficiency and the flexibility of this kind of existing gratings. Then, the design method for micro spectrometer optical system based on cross-asymmetrical Czerny-Turner structure’s studied. After comparison, the latter’s chosen as the basic optical structure for the micro fiber spectrometer. At last, the design of optical and mechanical system and thorough tolerance analysis of the integral hardware system were achieved utilizing optical and mechanical design and simulation softwares as CodeV, Tracepro and Solidworks. Furthermore, two types of spectral measurement accessories were designed based on practical applications. In the design of software system, the software system not only achieved the complete control of the spectrometer, basic spectral measurements and analysis function, but also realized a SDK based on two kinds of calling interfaces, which could highly extend system’s function and increase system’s practicability and flexibility. The results of a mass of various experiments show that the real system’s performance’s pretty high, the whole system is of high degree serialization and has strong hardware and software expansibility, thus, is competitive to its latest counterparts among foreign instruments. The whole system has already been put into mass production and marketing.Base on the realizing of micro fiber spectrometer, the traditional slit based dispersive spectrographic system model’s studied to find the reason for system performance’s restriction. A novel static high gain system model’s raised, in which traditional slit’s replaced by an orthogonal individual column coded aperture, which made it possible to extract the single channel’s spectrum from the superposed spectrum and achieved system’s dual advantages. Based on the derivation of the theoretical system model, a simulation system was setup to test its correctness and feasibility. The simulation and tolerance analysis results show that this system model is of very high performance and totally achievable. This novel high gain model highly optimizes the performance of traditional dispersive spectroscopic system and is of revolutionary sense for micro spectrometers based on 2D detectors.更多还原