紫外-可见光谱水质检测系统的多束LED光纤耦合研究

Research on Multi-Beam LED and Fiber Coupling of UV-Visible Spectroscopy Water Quality Detection System

摘要:

针对紫外-可见光谱水质检测系统单个LED光源输出功率低、光束质量差的问题,提出了一种多束紫外LED光源与光纤合束耦合的结构设计方案。运用ZEMAX光学分析软件开展了仿真设计研究,针对紫外LED光源与光纤耦合发散角较大的问题,设计了非球面准直透镜,准直后发散角为0.403mrad;针对光束尺寸与光纤的匹配问题,进行了消色差双分离聚焦耦合透镜的设计。实验结果表明,合束LED光束汇聚的弥散斑的RMS尺寸为186.412μm,GEO点尺寸为290.071μm,光束中95%以上的能量集中在300μm以内,实现了多束LED光源与光纤的高效耦合。

Abstract:

Aiming at the problems of low output power and poor optical quality of single LED in UV-Visible water quality monitoring system, a structural design of multi-beam UV LED light source coupled with optical fiber was proposed. Optical software of ZEMAX was used to make simulations, and the aspheric collimating lens was designed for the problem of large coupling divergence angle between the UV LED light source and fiber. The divergence angle after collimation is 0.403 mrad. To solve the matching problem between the beam size and the optical fiber, the achromatic double separation and focusing lens was designed. Experimenal results show the RMS size of LED beam combination is 186.412 μm, the GEO point is 290.071 μm, and more than 95% of the energy in the beam is concentrated within 300 μm, which realizes a high coupling efficiency of multi-beam LED with the optical fiber.